Under the rapidly warming climate in the Arctic and high mountain areas,permafrost is thawing,leading to various hazards at a global scale.One common permafrost hazard termed retrogressive thaw slump(RTS)occurs extens...Under the rapidly warming climate in the Arctic and high mountain areas,permafrost is thawing,leading to various hazards at a global scale.One common permafrost hazard termed retrogressive thaw slump(RTS)occurs extensively in ice-rich permafrost areas.Understanding the spatial and temporal distributive features of RTSs in a changing climate is crucial to assessing the damage to infrastructure and decision-making.To this end,we used a machine learning-based model to investigate the environmental factors that could lead to RTS occurrence and create a susceptibility map for RTS along the Qinghai-Tibet Engineering Corridor(QTEC)at a local scale.The results indicate that extreme summer climate events(e.g.,maximum air temperature and rainfall)contributes the most to the RTS occurrence over the flat areas with fine-grained soils.The model predicts that 13%(ca.22,948 km^(2))of the QTEC falls into high to very high susceptibility categories under the current climate over the permafrost areas with mean annual ground temperature at 10 m depth ranging from-3 to-1℃.This study provides insights into the impacts of permafrost thaw on the stability of landscape,carbon stock,and infrastructure,and the results are of value for engineering planning and maintenance.展开更多
2,4,6-trinitrotoluene(TNT) and its derivatives are nitrogen-containing aromatic compounds having chemical and thermal stability at ambient temperature and pressure. TNT has high toxicity and mutagenic activity to huma...2,4,6-trinitrotoluene(TNT) and its derivatives are nitrogen-containing aromatic compounds having chemical and thermal stability at ambient temperature and pressure. TNT has high toxicity and mutagenic activity to humans, plants and animals, thus decontamination processes are necessary. Many microorganisms are capable to bioremediate TNT such as bacteria from the genera Pseudomonas,Enterobacter, Rhodococcus, Mycobacterium, Clostridium and Desulfovibrio: fungus such as Phanerochate and Stropharia species are able to perform TNT biotransformation under aerobic and anaerobic conditions. In this work we review the state of TNT biodegradation by various routes: aerobic, anaerobic,combined, fungal, enzymatic, and bio-electrochemical.展开更多
Skeletochronology is a method commonly used for estimating the age of amphibians and reptiles in the wild. However, the number of lines of arrested growth （LAGs） does not necessarily reflect age in some species. We ...Skeletochronology is a method commonly used for estimating the age of amphibians and reptiles in the wild. However, the number of lines of arrested growth （LAGs） does not necessarily reflect age in some species. We validated the applicability of this method to an endangered eublepharid gecko, Goniurosaurus kuroiwae, then inferred its longevity and age structures in wild populations. We classified young geckos into three groups using previously published data for early growth： Group 1 contained hatchlings before the first winter, Group 2 contained hatchlings after the first win- ter, and Group 3 included yearlings after the second winter. LAG numbers in these groups were then compared. All individuals in Group 1 possessed a single LAG, which was considered as a hatching line. Most individuals in Groups 2 and 3 possessed one and two additional LAGs, respectively （LAG1 and LAG2）, corroborating the notion that LAGs are formed annually. A few geckos exhibited fewer LAGs than expected. Analysis of variations in LAG and marrow cavity diameter demonstrated that in animals with fewer LAGs, endosteal resorption or fusion of hatching line and LAG1 had occurred. LAG2 was never lost by endosteal resorption and was identifiable by its diameter. Thus, the age of adult geckos could be determined by counting LAGs outward from LAG2. Application of this method to wild populations re- vealed that the longevity of this species is not less than 83 months, but that almost all individuals in fragmented habitats die before 50 months, suggesting lower population sustainability in such habitats.展开更多
Surface sediment and seawater samples were collected from coastal areas around Okinawa Island from September 2001 to May 2002. The samples were analyzed for total polychlorinated biphenyl (PCB) levels and homolog comp...Surface sediment and seawater samples were collected from coastal areas around Okinawa Island from September 2001 to May 2002. The samples were analyzed for total polychlorinated biphenyl (PCB) levels and homolog composition. The results show that total PCB levels ranged from 0.32 to 128.7 ng/g (dry wt.) in sediment and 1.59 to 2.48 ng/L in seawater. The levels exceed the Environmental Quality Standard (EQS) for water pollution of Japan. The distribution of PCB homolog showed different patterns in the sediments and seawaters. Penta-chlorobiphenyls (CBs) comprised the main congener group in seawater, while hexa-CBs were more abundant homologs in the sediments. The heavily contaminated sites featured higher CBs, including penta-CBs, hexa-CBs, and hepta-CBs, than those in less contaminated sites where tri-CBs dominated. This study provides current distribution and geochemical behavior of PCBs in the coastal areas around Okinawa Island.展开更多
Plastic is a basic need for humans,but it has also caused big problems for the environment.Then,the purpose of this study was to determine the effect of the type of plastic and the addition of a zeolite catalyst on th...Plastic is a basic need for humans,but it has also caused big problems for the environment.Then,the purpose of this study was to determine the effect of the type of plastic and the addition of a zeolite catalyst on the oil yield from the pyrolysis of plastic waste.The research stages were natural zeolite activation,pyrolysis reactor settings,pyrolysis of plastic waste(PP and LDPE types),and characterization.The results showed that the used natural zeolite had a mordenite phase and activated natural zeolite had a higher Si/Al ratio than the inactivated one.The addition of a zeolite catalyst had an effect on the produced yield.The yields of oil from plastic waste pyrolysis with zeolite catalyst for PP and LDPE plastics were about 75.9 and 76.9 w/w,respectively.The results of the GCMS analysis showed that the compounds of the pyrolysis oil were thought to be from the alkanes,cycloalkanes,alkenes,carboxylic acids with aromatic rings,and ketones.The results of the GC-MS test showed that the uncatalyzed pyrolysis product consists of compounds with a range of C5-C11 carbon chains.Meanwhile,the ranges of pyrolysis products with active zeolite catalyst were C6-C24 carbon chains.展开更多
Despite serotonin’s and FMRF-amide’s wide distribution in the nervous system of invertebrates and their importance as neurotransmitters, the exact roles they play in neuronal networks leaves many questions. We mappe...Despite serotonin’s and FMRF-amide’s wide distribution in the nervous system of invertebrates and their importance as neurotransmitters, the exact roles they play in neuronal networks leaves many questions. We mapped the presence of serotonin and FMRF-amide-immunoreactivity in the central nervous system and eyes of the pond snail Lymnaea stagnalis and interpreted the results in connection with our earlier findings on the central projections of different peripheral nerves. Since the chemical nature of the intercellular connections in the retina of Lymnaea stagnalis is still largely unknown, we paid special attention to clarifying the role of serotonin and FMRF-amide in the visual system of this snail and compared our findings with those reported from other species. At least one serotonin-and one FMRF-amidergic fibre were labeled in each optic nerve, and since no cell bodies in the eye showed immunoreactivity to these neurotransmitters, we believe that efferent fibres with somata located in the central ganglia branch at the base of the eye and probably release 5HT and FMRF-amide as neuro-hormones. Double labelling revealed retrograde transport of neurobiotin through the optic nerve, allowing us to conclude that the central pathways and serotonin-and FMRF-amideimmunoreactive cells and fibres have different locations in the CNS in Lymnaea stagnalis. The chemical nature of the fibres, which connect the two eyes in Lymnaea stagnalis, is neither serotoninergic nor FMRF-amidergic.展开更多
Afferent and efferent neural elements of the retina and central ganglia in the freshwater snail Planorbarius corneus were labelled using retrograde transport of neurobiotin through the optic nerve.Axons of at least so...Afferent and efferent neural elements of the retina and central ganglia in the freshwater snail Planorbarius corneus were labelled using retrograde transport of neurobiotin through the optic nerve.Axons of at least some photoreceptor cells become direct contributors to the optic nerve as no synaptic junctions could be detected.The processes enter the cerebral ganglion and form a dense bundle of thin afferent fibres,the so-called optical neuropil.Efferent neurons were revealed in all ganglia,except the buccal ones.Some of the ascending axons branch in the cerebral ganglia,cross the cerebro-cerebral commissure,reach the contralateral eye and form arborizations in the eye cup.Some efferent neurons send axons to different peripheral nerves as well：n.n.intestinalis,pallialis dexter,pallialis sinister internus et externus.Serotonin-and FMRF-amide-ergic fibres were revealed in the optic nerve.These fibres belong to those central neurons which send their axons to the ipsilateral eye only.They form abundant varicoses in the eye cup and nuclear layer of the retina,and possibly help to regulate retinal sensitivity to light.展开更多
Despite serotonin’s and FMRF-amide’s wide distribution in the nervous system of invertebrates and their importance as neurotransmitters,the exact roles they play in neuronal networks leaves many questions.We mapped ...Despite serotonin’s and FMRF-amide’s wide distribution in the nervous system of invertebrates and their importance as neurotransmitters,the exact roles they play in neuronal networks leaves many questions.We mapped the presence of serotonin and FMRF-amide-immunoreactivity in the central nervous system and eyes of the pond snail Lymnaea stagnalis and interpreted the results in connection with our earlier findings on the central projections of different peripheral nerves.Since the chemical nature of the intercellular connections in the retina of L.stagnalis is still largely unknown,we paid special attention to clarifying the role of serotonin and FMRF-amide in the visual system of this snail and compared our findings with those reported from other species.At least one serotonin-and one FMRF-amidergic fibre were labeled in each optic nerve,and since no cell bodies in the eye showed immunoreactivity to these neurotransmitters,we believe that efferent fibres with somata located in the central ganglia branch at the base of the eye and probably release 5HT and FMRF-amide as neuro-hormones.Double labelling revealed retrograde transport of neurobiotin through the optic nerve,allowing us to conclude that the central pathways and serotonin-and FMRF-amide-immunoreactive cells and fibres have different locations in the CNS in L.stagnalis.The chemical nature of the fibres,which connect the two eyes in L.stagnalis,is neither serotoninergic nor FMRF-amidergic.展开更多
Petrography, carbon and oxygen isotopic study was carried out to interpret isotopic variations on the predominant carbonate sequence of the Dalmiapuram Formation of the Cauvery Basin, South India. The common petrograp...Petrography, carbon and oxygen isotopic study was carried out to interpret isotopic variations on the predominant carbonate sequence of the Dalmiapuram Formation of the Cauvery Basin, South India. The common petrographic types identified in the Dalmiapuram Formation range from wackestone to boundstone. The gray shale and limestone members show large variations in d13 C and d18 O values(Gray shale member: +1.44 to +2.40 %VPDB,-3.05 to-5.92 % VPDB, respectively; Limestone member:-6.07 to +2.93 % VPDB;-7.08 to-0.39 %VPDB; respectively). In the present study, the carbon and oxygen values are not correlated, which supports the fact that these limestones retain their primary isotopic signatures. In carbon isotope curve, one negative shift is identified in the gray shale member and a positive isotopic excursion is detected in the coral algal limestone(CAL).The observed positive isotopic excursion in the lower part of the CAL correlates with OAE1 d and suggests the global nature of the late Albian OAE1 d in the Cauvery Basin.展开更多
In this experiment, the effects of the combination of jets or rods and a porous cavity on the supersonic flow field are studied by means of visualization of schlieren method and the measurements of wall static pressur...In this experiment, the effects of the combination of jets or rods and a porous cavity on the supersonic flow field are studied by means of visualization of schlieren method and the measurements of wall static pressures and the flow direction in the cavity with the thermal tuft probe. Three cases of jets or rods arrangements are tested in the experiments. As a result, a bow shock wave which is generated by the jets or rods is observed by mean of schlieren method. And it is confirmed that the expansion region appears downstream of the rods but is not in case of the jets pattern. Moreover the pressure ratios of starting shock wave passing through porous cavity for jets pattern differ from that of rods pattern. In the cavity, the flow direction at the measurement position in the cavity is always opposite to the main flow, as long as the starting shock wave is located upstream of the porous cavity for all cases. Difference in the backward flow ratio between the jets and rods patterns is observe after the starting shock wave passes through the porous cavity.展开更多
This paper presents a study on the improvement of MLNNs(multi-layer neural networks)performance by an activity function for multi logic training patterns.Our model network has L hidden layers of two inputs and three,f...This paper presents a study on the improvement of MLNNs(multi-layer neural networks)performance by an activity function for multi logic training patterns.Our model network has L hidden layers of two inputs and three,four to six output training using BP(backpropagation)neural network.We used logic functions of XOR(exclusive OR),OR,AND,NAND(not AND),NXOR(not exclusive OR)and NOR(not OR)as the multi logic teacher signals to evaluate the training performance of MLNNs by an activity function for information and data enlargement in signal processing(synaptic divergence state).We specifically used four activity functions from which we modified one and called it L&exp.function as it could give the highest training abilities compared to the original activity functions of Sigmoid,ReLU and Step during simulation and training in the network.And finally,we propose L&exp.function as being good for MLNNs and it may be applicable for signal processing of data and information enlargement because of its performance training characteristics with multiple training logic patterns hence can be adopted in machine deep learning.展开更多
Organic-inorganic hybrid</span><b> </b><span style="font-family:Verdana;">network polymers have been synthesized by addition reaction of a thiol-functionalized random type silsesquiox...Organic-inorganic hybrid</span><b> </b><span style="font-family:Verdana;">network polymers have been synthesized by addition reaction of a thiol-functionalized random type silsesquioxane (SQ109) and alkyl diacrylate or diisocyanate compounds. Thiol-ene reaction of SQ109 and 1,4-butanediol diacrylate (BDA) successfully yield porous polymer in toluene initiated by azobis</span></span><span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">isobutyronitrile</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> (AIBN) at 60</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">C. Morphology of the porous polymers was composed by connected globules, and the diameter of the globules decreased with increasing in the monomer concentration </span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> the reaction </span><span style="font-family:Verdana;">system</span><span style="font-family:""><span style="font-family:Verdana;">. By contrast, the reaction with 1,6-hexanediol diacrylate or </span><span style="font-family:Verdana;">1,5-hexadiene yielded homogeneous clear gels. Thermal analyses of SQ109-BDA</span><span style="font-family:Verdana;"> porous polymers indicated that thermal degradation of ester groups of BDA in the polymer network occurred at around 300</span></span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">C. The porous polymer was also obtained </span><span style="font-family:Verdana;">by</span><span style="font-family:Verdana;"> the reaction </span><span style="font-family:Verdana;">using</span><span style="font-family:""><span style="font-family:Verdana;"> a photo-initiator (Irugacure184) at room temperature, and showed higher Young’s modulus than the corresponding porous polymer obtained with the reaction with AIBN due to the small size of </span><span style="font-family:Verdana;">the globules. Young’s modulus of SQ109-BDA porous polymer increased</span><span style="font-family:Verdana;"> with </span><span style="font-family:Verdana;">increasing in the monomer concentration </span></span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> the reaction systems. Thioliso</span><span style="font-family:""><span style="font-family:Verdana;">cyanate addition reactions between SQ109 </span><span style="font-family:Verdana;">and hexamethylene diisocyanate (HDI) or methylenediphenyl 4,4’-diisocyanate</span><span style="font-family:Verdana;"> (MDI) were investigated to obtain network polymers. The reactions in toluene yielded the corresponding homogeneous clear gels. By contrast the reactions in a mixed solvent of toluene (50 vol.%) and </span><i><span style="font-family:Verdana;">N,N</span></i><span style="font-family:Verdana;">-dimethylformamide (50 vol.%) produced porous polymers. The morphology of the porous polymers was composed by connected </span><span style="font-family:Verdana;">globules or aggregated particles. The size of globules and particles in the</span><span style="font-family:Verdana;"> SQ109-HDI porous polymers was larger </span><span style="font-family:Verdana;">than </span></span><span style="font-family:Verdana;">those</span><span style="font-family:Verdana;"> in the SQ109-MDI porous polymers. Thermal degradation of SQ109-HDI and SQ109-MDI porous polymers</span><span style="font-family:Verdana;"> started at round 260</span><span style="font-family:Verdana;">°</span><span style="font-family:""><span style="font-family:Verdana;">C and showed </span><span style="font-family:Verdana;">endothermic peak at around 350</span></span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">C derived from degradation of </span><span style="font-family:Verdana;">thio-urethane bond.展开更多
We produced Wood-Polymer Composites (WPCs) with phenolic resin (PR) filled with saw dust (SD) and rice husks (RH) in a PR:fillerratio of 60:40 wt.%. RH and SD were grinded and sieved into particles μm. The aim of thi...We produced Wood-Polymer Composites (WPCs) with phenolic resin (PR) filled with saw dust (SD) and rice husks (RH) in a PR:fillerratio of 60:40 wt.%. RH and SD were grinded and sieved into particles μm. The aim of this research work was to evaluate sawdust and rice husks as fillers for sustainable phenolic resin based WPCs. Therefore, we investigated the thermal stability of PR/RH and PR/SD WPCs then we studied and compared the tensile, flexural properties of PR/SD and PR/RH WPCs samples, as well as their dimensional stability after water absorption test. Furthermore, through ultraviolet light exposure, we evaluated the effects of photo-oxidation on the water stability and mechanical properties of PR/RH and PR/SD WPCs samples compared to unexposed ones. PR filled with SD presented better mechanical properties compared to PR/RH WPCs samples. However, PR/RH WPCs showed good mechanical properties, and better thermal resistance and better water repulsion capabilities compared to PR/SD WPCs samples. Although, long time UV exposure ended up lowering considerably the mechanical properties and water resistance of PR/SD and PR/RH WPCs, both RH and SD offer great added value as fillers for PR based WPCs;SD having better interactions with PR matrix compared to RH.展开更多
A complex terrain and topography resulted in an enormous landslide-dammed area northeast of Afghanistan. Moreover, debris, rock avalanches, and landslides occurrences are the primary source of lakes created within the...A complex terrain and topography resulted in an enormous landslide-dammed area northeast of Afghanistan. Moreover, debris, rock avalanches, and landslides occurrences are the primary source of lakes created within the area. Recently, instances have increased because of the high displacement and mass movement by glacial and seismic activities. In this study, using GIS and R statistical software, we performed a logistic regression modeling in order to map and predict the probability of landslides-dammed occurrences. Totally, 361 lakes were mapped using Google Earth historical imagery. This total was divided into 253 （70%） lakes for modeling and 801 （30%） lakes for the model validation. They were randomly selected by creating a fishnet for the study area using Arc toolbox in GIS. Four independent variables that are mostly contributed to landslide-dammed occurrences consisting of slope angles, relief classes, distances to major water sources and earthquake epicenters, were extracted from DEM （digital elevation model） data using 85-meter resolution. The result is a grid map that classified the area into Low （16,834.98 km2）, Medium （2,217.302 kin：） and High （2,013.55 km2） vulnerability to landslide-dammed occurrences. Overall, the model result has been validated by using a ROC （receiver operator characteristic） curve available in SPSS software. The model validation showed a 95.1 percent prediction accuracy that is considered satisfactory.展开更多
Piper (1944) diagram has been the basis for several important interpretations of the hydrogeochemical data. As seen in this diagram, most natural waters contain relatively few dissolved constituents, with cations (met...Piper (1944) diagram has been the basis for several important interpretations of the hydrogeochemical data. As seen in this diagram, most natural waters contain relatively few dissolved constituents, with cations (metals or bases) and anions (acid radicles) in chemical equilibrium with one another. Apart from the facies representation, the composition of the mixed sample can be identified in terms of the composition of the parental solution. To bring out this advantage of the Piper diagram, a study was conducted in the Kalpakkam region of Tamilnadu, South India. By taking the geology and water table into consideration, two sample locations were selected as parent solution and third one as the mixture sample. All three samples were analyzed for calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), sulphate (SO4) and phosphate (PO4) by Ion Chromatograph (Metrohm IC 861). HCO3 was determined by volumetric titration. The Piper diagram shows that parent solutions clustered towards Na-Mg-Ca-HCO3-Cl and Na-HCO3 facies, and the mixing sample belongs to Na-Mg-HCO3 facies. Phreeqc interac-tive (Ver 2.8) along with the original composition of the mixture sample was used to correlate the mixing proportion identified by the Piper diagram.展开更多
The geological strength index(GSI) system,widely used for the design and practice of mining process,is a unique rock mass classification system related to the rock mass strength and deformation parameters based on the...The geological strength index(GSI) system,widely used for the design and practice of mining process,is a unique rock mass classification system related to the rock mass strength and deformation parameters based on the generalized Hoek-Brown and Mohr-Coulomb failure criteria.The GSI can be estimated using standard chart and field observations of rock mass blockiness and discontinuity surface conditions.The GSI value gives a numerical representation of the overall geotechnical quality of the rock mass.In this study,we propose a method to determine the GSI quantitatively using photographic images of in situ jointed rock mass with image processing technology,fractal theory and artificial neural network(ANN).We employ the GSI system to characterize the jointed rock mass around the working in a coal mine.The relative error between the proposed value and the given value in the GSI chart is less than 3.6%.展开更多
The free thermal vibration of functionally graded material(FGM) cylindrical shells containing porosities is investigated. Both even distribution and uneven distribution are taken into account. In addition, three therm...The free thermal vibration of functionally graded material(FGM) cylindrical shells containing porosities is investigated. Both even distribution and uneven distribution are taken into account. In addition, three thermal load types, i.e., uniform temperature rise(UTR), nonlinear temperature rise(NLTR), and linear temperature rise(LTR), are researched to explore their effects on the vibration characteristics of porous FGM cylindrical shells. A modified power-law formulation is used to describe the material properties of FGM shells in the thickness direction. Love’s shell theory is used to formulate the straindisplacement equations, and the Rayleigh-Ritz method is utilized to calculate the natural frequencies of the system. The results show that the natural frequencies are affected by the porosity volume fraction, constituent volume fraction, and thermal load. Moreover,the natural frequencies obtained from the LTR have insignificant differences compared with those from the NLTR. Due to the calculation complexity of the NLTR, we propose that it is reasonable to replace it by its linear counterpart for the analysis of thin porous FGM cylindrical shells. The present results are verified in comparison with the published ones in the literature.展开更多
The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into a...The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into account. Based on the nonlocal elasticity theory and Donnell's nonlinear shell theory, the nonlinear governing equations and the corresponding boundary conditions are derived by employing Hamilton's principle. Then,the Galerkin method is used to transform the governing equations into a set of ordinary differential equations, and subsequently, the multiple-scale method is used to obtain an approximate analytical solution. Finally, an extensive parametric study is conducted to examine the effects of the nonlocal parameter, the external electric potential, the temperature rise, and the Winkler-Pasternak foundation parameters on the nonlinear vibration characteristics of circular cylindrical piezoelectric nanoshells.展开更多
The trend of distance learning education has increased year by year because of the rapid advancement of information and communication technologies. Distance learning system can be regarded as one of ubiquitous computi...The trend of distance learning education has increased year by year because of the rapid advancement of information and communication technologies. Distance learning system can be regarded as one of ubiquitous computing applications since the learners can study anywhere even in mobile environments. However, the instructor cannot know if the learners comprehend the lecture or not since each learner is physically isolated. Therefore, a framework which detects the learners’ concentration condition is required. If a distance learning system obtains the information that many learners are not concentrated on the class due to the incomprehensible lecture style, the instructor can perceive it through the system and change the presentation strategy. This is a context-aware technology which is widely used for ubiquitous computing services. In this paper, an efficient distance learning system, which accurately detects learners’ concentration condition during a class, is proposed. The proposed system uses multiple biological information which are learners’ eye movement metrics, i.e. fixation counts, fixation rate, fixation duration and average saccade length obtained by an eye tracking system. The learners’ concentration condition is classified by using machine learning techniques. The proposed system has performed the detection accuracy of 90.7% when Multilayer Perceptron is used as a classifier. In addition, the effectiveness of the proposed eye metrics has been confirmed. Furthermore, it has been clarified that the fixation duration is the most important eye metric among the four metrics based on the investigation of evaluation experiment.展开更多
In this article,we consider a fully nonlinear partial differential equation which can be expressed as a sum of two Monge-Ampere operators acting in different two-dimensional coordinate sections.This equation is ellipt...In this article,we consider a fully nonlinear partial differential equation which can be expressed as a sum of two Monge-Ampere operators acting in different two-dimensional coordinate sections.This equation is elliptic,for example,in the class of convex functions.We show that the notion of Monge-Ampere measures and Aleksandrov generalized solutions extends to this equation,subject to a weaker notion of convexity which we call bi-planar convexity.While the equation is also elliptic in the class of bi-planar convex functions,the contrary is not necessarily true.This is a substantial difference compared to the classical Monge-Ampere equation where ellipticity and convexity coincide.We provide explicit counter-examples:classical solutions to the bi-planar equation that satisfy the ellipticity condition but are not generalized solutions in the sense introduced.We conclude that the concept of generalized solutions based on convexity arguments is not a natural setting for the bi-planar equation.展开更多
基金funded by the National Natural Science Foundation of China(42372334)the Science and Technology Research and Development Program of the Qinghai-Tibet Group Corporation(Grant No.QZ2022-G05)。
文摘Under the rapidly warming climate in the Arctic and high mountain areas,permafrost is thawing,leading to various hazards at a global scale.One common permafrost hazard termed retrogressive thaw slump(RTS)occurs extensively in ice-rich permafrost areas.Understanding the spatial and temporal distributive features of RTSs in a changing climate is crucial to assessing the damage to infrastructure and decision-making.To this end,we used a machine learning-based model to investigate the environmental factors that could lead to RTS occurrence and create a susceptibility map for RTS along the Qinghai-Tibet Engineering Corridor(QTEC)at a local scale.The results indicate that extreme summer climate events(e.g.,maximum air temperature and rainfall)contributes the most to the RTS occurrence over the flat areas with fine-grained soils.The model predicts that 13%(ca.22,948 km^(2))of the QTEC falls into high to very high susceptibility categories under the current climate over the permafrost areas with mean annual ground temperature at 10 m depth ranging from-3 to-1℃.This study provides insights into the impacts of permafrost thaw on the stability of landscape,carbon stock,and infrastructure,and the results are of value for engineering planning and maintenance.
基金the Director of the School of Engineering and Science, Tecnológico de Monterrey, Campus Monterrey for his encouragement and financial supportthe financial support from CONACYT(Mexico)PhD scholarship No. 309171 for CCZ, SNI-C fellowship to RC and MR, FRAavesh green sustainability solutions S. De R. L. De. C. V. for their support
文摘2,4,6-trinitrotoluene(TNT) and its derivatives are nitrogen-containing aromatic compounds having chemical and thermal stability at ambient temperature and pressure. TNT has high toxicity and mutagenic activity to humans, plants and animals, thus decontamination processes are necessary. Many microorganisms are capable to bioremediate TNT such as bacteria from the genera Pseudomonas,Enterobacter, Rhodococcus, Mycobacterium, Clostridium and Desulfovibrio: fungus such as Phanerochate and Stropharia species are able to perform TNT biotransformation under aerobic and anaerobic conditions. In this work we review the state of TNT biodegradation by various routes: aerobic, anaerobic,combined, fungal, enzymatic, and bio-electrochemical.
基金supported by the Zoshinkai Fund for Protection of Endangered Animals and the Grant from the Japan Society for the Promotion of Science (JSPS KAKENHI Grant number 22510244)
文摘Skeletochronology is a method commonly used for estimating the age of amphibians and reptiles in the wild. However, the number of lines of arrested growth （LAGs） does not necessarily reflect age in some species. We validated the applicability of this method to an endangered eublepharid gecko, Goniurosaurus kuroiwae, then inferred its longevity and age structures in wild populations. We classified young geckos into three groups using previously published data for early growth： Group 1 contained hatchlings before the first winter, Group 2 contained hatchlings after the first win- ter, and Group 3 included yearlings after the second winter. LAG numbers in these groups were then compared. All individuals in Group 1 possessed a single LAG, which was considered as a hatching line. Most individuals in Groups 2 and 3 possessed one and two additional LAGs, respectively （LAG1 and LAG2）, corroborating the notion that LAGs are formed annually. A few geckos exhibited fewer LAGs than expected. Analysis of variations in LAG and marrow cavity diameter demonstrated that in animals with fewer LAGs, endosteal resorption or fusion of hatching line and LAG1 had occurred. LAG2 was never lost by endosteal resorption and was identifiable by its diameter. Thus, the age of adult geckos could be determined by counting LAGs outward from LAG2. Application of this method to wild populations re- vealed that the longevity of this species is not less than 83 months, but that almost all individuals in fragmented habitats die before 50 months, suggesting lower population sustainability in such habitats.
基金This study was conducted with financial support from the Ministry of Education, Culture, Sports, Science and Technology, Japan as a Msc. Scholarship for Special Program of Marine Science awarded to Sheikh, M.A. (from 2000–2002)21st Century COE program of the University of the Ryukyus, awarded to Sheikh, M. A. as a visiting researcher from March–May 2005).
文摘Surface sediment and seawater samples were collected from coastal areas around Okinawa Island from September 2001 to May 2002. The samples were analyzed for total polychlorinated biphenyl (PCB) levels and homolog composition. The results show that total PCB levels ranged from 0.32 to 128.7 ng/g (dry wt.) in sediment and 1.59 to 2.48 ng/L in seawater. The levels exceed the Environmental Quality Standard (EQS) for water pollution of Japan. The distribution of PCB homolog showed different patterns in the sediments and seawaters. Penta-chlorobiphenyls (CBs) comprised the main congener group in seawater, while hexa-CBs were more abundant homologs in the sediments. The heavily contaminated sites featured higher CBs, including penta-CBs, hexa-CBs, and hepta-CBs, than those in less contaminated sites where tri-CBs dominated. This study provides current distribution and geochemical behavior of PCBs in the coastal areas around Okinawa Island.
基金the work,namely:PNBP No.4.3.13/UN32/KP/2021 by Assoc.Prof.Aman Santoso.
文摘Plastic is a basic need for humans,but it has also caused big problems for the environment.Then,the purpose of this study was to determine the effect of the type of plastic and the addition of a zeolite catalyst on the oil yield from the pyrolysis of plastic waste.The research stages were natural zeolite activation,pyrolysis reactor settings,pyrolysis of plastic waste(PP and LDPE types),and characterization.The results showed that the used natural zeolite had a mordenite phase and activated natural zeolite had a higher Si/Al ratio than the inactivated one.The addition of a zeolite catalyst had an effect on the produced yield.The yields of oil from plastic waste pyrolysis with zeolite catalyst for PP and LDPE plastics were about 75.9 and 76.9 w/w,respectively.The results of the GCMS analysis showed that the compounds of the pyrolysis oil were thought to be from the alkanes,cycloalkanes,alkenes,carboxylic acids with aromatic rings,and ketones.The results of the GC-MS test showed that the uncatalyzed pyrolysis product consists of compounds with a range of C5-C11 carbon chains.Meanwhile,the ranges of pyrolysis products with active zeolite catalyst were C6-C24 carbon chains.
文摘Despite serotonin’s and FMRF-amide’s wide distribution in the nervous system of invertebrates and their importance as neurotransmitters, the exact roles they play in neuronal networks leaves many questions. We mapped the presence of serotonin and FMRF-amide-immunoreactivity in the central nervous system and eyes of the pond snail Lymnaea stagnalis and interpreted the results in connection with our earlier findings on the central projections of different peripheral nerves. Since the chemical nature of the intercellular connections in the retina of Lymnaea stagnalis is still largely unknown, we paid special attention to clarifying the role of serotonin and FMRF-amide in the visual system of this snail and compared our findings with those reported from other species. At least one serotonin-and one FMRF-amidergic fibre were labeled in each optic nerve, and since no cell bodies in the eye showed immunoreactivity to these neurotransmitters, we believe that efferent fibres with somata located in the central ganglia branch at the base of the eye and probably release 5HT and FMRF-amide as neuro-hormones. Double labelling revealed retrograde transport of neurobiotin through the optic nerve, allowing us to conclude that the central pathways and serotonin-and FMRF-amideimmunoreactive cells and fibres have different locations in the CNS in Lymnaea stagnalis. The chemical nature of the fibres, which connect the two eyes in Lymnaea stagnalis, is neither serotoninergic nor FMRF-amidergic.
文摘Afferent and efferent neural elements of the retina and central ganglia in the freshwater snail Planorbarius corneus were labelled using retrograde transport of neurobiotin through the optic nerve.Axons of at least some photoreceptor cells become direct contributors to the optic nerve as no synaptic junctions could be detected.The processes enter the cerebral ganglion and form a dense bundle of thin afferent fibres,the so-called optical neuropil.Efferent neurons were revealed in all ganglia,except the buccal ones.Some of the ascending axons branch in the cerebral ganglia,cross the cerebro-cerebral commissure,reach the contralateral eye and form arborizations in the eye cup.Some efferent neurons send axons to different peripheral nerves as well：n.n.intestinalis,pallialis dexter,pallialis sinister internus et externus.Serotonin-and FMRF-amide-ergic fibres were revealed in the optic nerve.These fibres belong to those central neurons which send their axons to the ipsilateral eye only.They form abundant varicoses in the eye cup and nuclear layer of the retina,and possibly help to regulate retinal sensitivity to light.
基金This work was supported by DAAD student fellowship
文摘Despite serotonin’s and FMRF-amide’s wide distribution in the nervous system of invertebrates and their importance as neurotransmitters,the exact roles they play in neuronal networks leaves many questions.We mapped the presence of serotonin and FMRF-amide-immunoreactivity in the central nervous system and eyes of the pond snail Lymnaea stagnalis and interpreted the results in connection with our earlier findings on the central projections of different peripheral nerves.Since the chemical nature of the intercellular connections in the retina of L.stagnalis is still largely unknown,we paid special attention to clarifying the role of serotonin and FMRF-amide in the visual system of this snail and compared our findings with those reported from other species.At least one serotonin-and one FMRF-amidergic fibre were labeled in each optic nerve,and since no cell bodies in the eye showed immunoreactivity to these neurotransmitters,we believe that efferent fibres with somata located in the central ganglia branch at the base of the eye and probably release 5HT and FMRF-amide as neuro-hormones.Double labelling revealed retrograde transport of neurobiotin through the optic nerve,allowing us to conclude that the central pathways and serotonin-and FMRF-amide-immunoreactive cells and fibres have different locations in the CNS in L.stagnalis.The chemical nature of the fibres,which connect the two eyes in L.stagnalis,is neither serotoninergic nor FMRF-amidergic.
基金supported by DGAPA, Universidad Nacional Autónoma de Mexico through the PASPA Project
文摘Petrography, carbon and oxygen isotopic study was carried out to interpret isotopic variations on the predominant carbonate sequence of the Dalmiapuram Formation of the Cauvery Basin, South India. The common petrographic types identified in the Dalmiapuram Formation range from wackestone to boundstone. The gray shale and limestone members show large variations in d13 C and d18 O values(Gray shale member: +1.44 to +2.40 %VPDB,-3.05 to-5.92 % VPDB, respectively; Limestone member:-6.07 to +2.93 % VPDB;-7.08 to-0.39 %VPDB; respectively). In the present study, the carbon and oxygen values are not correlated, which supports the fact that these limestones retain their primary isotopic signatures. In carbon isotope curve, one negative shift is identified in the gray shale member and a positive isotopic excursion is detected in the coral algal limestone(CAL).The observed positive isotopic excursion in the lower part of the CAL correlates with OAE1 d and suggests the global nature of the late Albian OAE1 d in the Cauvery Basin.
文摘In this experiment, the effects of the combination of jets or rods and a porous cavity on the supersonic flow field are studied by means of visualization of schlieren method and the measurements of wall static pressures and the flow direction in the cavity with the thermal tuft probe. Three cases of jets or rods arrangements are tested in the experiments. As a result, a bow shock wave which is generated by the jets or rods is observed by mean of schlieren method. And it is confirmed that the expansion region appears downstream of the rods but is not in case of the jets pattern. Moreover the pressure ratios of starting shock wave passing through porous cavity for jets pattern differ from that of rods pattern. In the cavity, the flow direction at the measurement position in the cavity is always opposite to the main flow, as long as the starting shock wave is located upstream of the porous cavity for all cases. Difference in the backward flow ratio between the jets and rods patterns is observe after the starting shock wave passes through the porous cavity.
文摘This paper presents a study on the improvement of MLNNs(multi-layer neural networks)performance by an activity function for multi logic training patterns.Our model network has L hidden layers of two inputs and three,four to six output training using BP(backpropagation)neural network.We used logic functions of XOR(exclusive OR),OR,AND,NAND(not AND),NXOR(not exclusive OR)and NOR(not OR)as the multi logic teacher signals to evaluate the training performance of MLNNs by an activity function for information and data enlargement in signal processing(synaptic divergence state).We specifically used four activity functions from which we modified one and called it L&exp.function as it could give the highest training abilities compared to the original activity functions of Sigmoid,ReLU and Step during simulation and training in the network.And finally,we propose L&exp.function as being good for MLNNs and it may be applicable for signal processing of data and information enlargement because of its performance training characteristics with multiple training logic patterns hence can be adopted in machine deep learning.
文摘Organic-inorganic hybrid</span><b> </b><span style="font-family:Verdana;">network polymers have been synthesized by addition reaction of a thiol-functionalized random type silsesquioxane (SQ109) and alkyl diacrylate or diisocyanate compounds. Thiol-ene reaction of SQ109 and 1,4-butanediol diacrylate (BDA) successfully yield porous polymer in toluene initiated by azobis</span></span><span style="font-family:Verdana;">(</span><span style="font-family:Verdana;">isobutyronitrile</span><span style="font-family:Verdana;">)</span><span style="font-family:Verdana;"> (AIBN) at 60</span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">C. Morphology of the porous polymers was composed by connected globules, and the diameter of the globules decreased with increasing in the monomer concentration </span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> the reaction </span><span style="font-family:Verdana;">system</span><span style="font-family:""><span style="font-family:Verdana;">. By contrast, the reaction with 1,6-hexanediol diacrylate or </span><span style="font-family:Verdana;">1,5-hexadiene yielded homogeneous clear gels. Thermal analyses of SQ109-BDA</span><span style="font-family:Verdana;"> porous polymers indicated that thermal degradation of ester groups of BDA in the polymer network occurred at around 300</span></span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">C. The porous polymer was also obtained </span><span style="font-family:Verdana;">by</span><span style="font-family:Verdana;"> the reaction </span><span style="font-family:Verdana;">using</span><span style="font-family:""><span style="font-family:Verdana;"> a photo-initiator (Irugacure184) at room temperature, and showed higher Young’s modulus than the corresponding porous polymer obtained with the reaction with AIBN due to the small size of </span><span style="font-family:Verdana;">the globules. Young’s modulus of SQ109-BDA porous polymer increased</span><span style="font-family:Verdana;"> with </span><span style="font-family:Verdana;">increasing in the monomer concentration </span></span><span style="font-family:Verdana;">of</span><span style="font-family:Verdana;"> the reaction systems. Thioliso</span><span style="font-family:""><span style="font-family:Verdana;">cyanate addition reactions between SQ109 </span><span style="font-family:Verdana;">and hexamethylene diisocyanate (HDI) or methylenediphenyl 4,4’-diisocyanate</span><span style="font-family:Verdana;"> (MDI) were investigated to obtain network polymers. The reactions in toluene yielded the corresponding homogeneous clear gels. By contrast the reactions in a mixed solvent of toluene (50 vol.%) and </span><i><span style="font-family:Verdana;">N,N</span></i><span style="font-family:Verdana;">-dimethylformamide (50 vol.%) produced porous polymers. The morphology of the porous polymers was composed by connected </span><span style="font-family:Verdana;">globules or aggregated particles. The size of globules and particles in the</span><span style="font-family:Verdana;"> SQ109-HDI porous polymers was larger </span><span style="font-family:Verdana;">than </span></span><span style="font-family:Verdana;">those</span><span style="font-family:Verdana;"> in the SQ109-MDI porous polymers. Thermal degradation of SQ109-HDI and SQ109-MDI porous polymers</span><span style="font-family:Verdana;"> started at round 260</span><span style="font-family:Verdana;">°</span><span style="font-family:""><span style="font-family:Verdana;">C and showed </span><span style="font-family:Verdana;">endothermic peak at around 350</span></span><span style="font-family:Verdana;">°</span><span style="font-family:Verdana;">C derived from degradation of </span><span style="font-family:Verdana;">thio-urethane bond.
文摘We produced Wood-Polymer Composites (WPCs) with phenolic resin (PR) filled with saw dust (SD) and rice husks (RH) in a PR:fillerratio of 60:40 wt.%. RH and SD were grinded and sieved into particles μm. The aim of this research work was to evaluate sawdust and rice husks as fillers for sustainable phenolic resin based WPCs. Therefore, we investigated the thermal stability of PR/RH and PR/SD WPCs then we studied and compared the tensile, flexural properties of PR/SD and PR/RH WPCs samples, as well as their dimensional stability after water absorption test. Furthermore, through ultraviolet light exposure, we evaluated the effects of photo-oxidation on the water stability and mechanical properties of PR/RH and PR/SD WPCs samples compared to unexposed ones. PR filled with SD presented better mechanical properties compared to PR/RH WPCs samples. However, PR/RH WPCs showed good mechanical properties, and better thermal resistance and better water repulsion capabilities compared to PR/SD WPCs samples. Although, long time UV exposure ended up lowering considerably the mechanical properties and water resistance of PR/SD and PR/RH WPCs, both RH and SD offer great added value as fillers for PR based WPCs;SD having better interactions with PR matrix compared to RH.
文摘A complex terrain and topography resulted in an enormous landslide-dammed area northeast of Afghanistan. Moreover, debris, rock avalanches, and landslides occurrences are the primary source of lakes created within the area. Recently, instances have increased because of the high displacement and mass movement by glacial and seismic activities. In this study, using GIS and R statistical software, we performed a logistic regression modeling in order to map and predict the probability of landslides-dammed occurrences. Totally, 361 lakes were mapped using Google Earth historical imagery. This total was divided into 253 （70%） lakes for modeling and 801 （30%） lakes for the model validation. They were randomly selected by creating a fishnet for the study area using Arc toolbox in GIS. Four independent variables that are mostly contributed to landslide-dammed occurrences consisting of slope angles, relief classes, distances to major water sources and earthquake epicenters, were extracted from DEM （digital elevation model） data using 85-meter resolution. The result is a grid map that classified the area into Low （16,834.98 km2）, Medium （2,217.302 kin：） and High （2,013.55 km2） vulnerability to landslide-dammed occurrences. Overall, the model result has been validated by using a ROC （receiver operator characteristic） curve available in SPSS software. The model validation showed a 95.1 percent prediction accuracy that is considered satisfactory.
文摘Piper (1944) diagram has been the basis for several important interpretations of the hydrogeochemical data. As seen in this diagram, most natural waters contain relatively few dissolved constituents, with cations (metals or bases) and anions (acid radicles) in chemical equilibrium with one another. Apart from the facies representation, the composition of the mixed sample can be identified in terms of the composition of the parental solution. To bring out this advantage of the Piper diagram, a study was conducted in the Kalpakkam region of Tamilnadu, South India. By taking the geology and water table into consideration, two sample locations were selected as parent solution and third one as the mixture sample. All three samples were analyzed for calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), sulphate (SO4) and phosphate (PO4) by Ion Chromatograph (Metrohm IC 861). HCO3 was determined by volumetric titration. The Piper diagram shows that parent solutions clustered towards Na-Mg-Ca-HCO3-Cl and Na-HCO3 facies, and the mixing sample belongs to Na-Mg-HCO3 facies. Phreeqc interac-tive (Ver 2.8) along with the original composition of the mixture sample was used to correlate the mixing proportion identified by the Piper diagram.
文摘The geological strength index(GSI) system,widely used for the design and practice of mining process,is a unique rock mass classification system related to the rock mass strength and deformation parameters based on the generalized Hoek-Brown and Mohr-Coulomb failure criteria.The GSI can be estimated using standard chart and field observations of rock mass blockiness and discontinuity surface conditions.The GSI value gives a numerical representation of the overall geotechnical quality of the rock mass.In this study,we propose a method to determine the GSI quantitatively using photographic images of in situ jointed rock mass with image processing technology,fractal theory and artificial neural network(ANN).We employ the GSI system to characterize the jointed rock mass around the working in a coal mine.The relative error between the proposed value and the given value in the GSI chart is less than 3.6%.
基金Project supported by the National Natural Science Foundation of China(No.11672071)the Fundamental Research Funds for the Central Universities(No.N170504023)
文摘The free thermal vibration of functionally graded material(FGM) cylindrical shells containing porosities is investigated. Both even distribution and uneven distribution are taken into account. In addition, three thermal load types, i.e., uniform temperature rise(UTR), nonlinear temperature rise(NLTR), and linear temperature rise(LTR), are researched to explore their effects on the vibration characteristics of porous FGM cylindrical shells. A modified power-law formulation is used to describe the material properties of FGM shells in the thickness direction. Love’s shell theory is used to formulate the straindisplacement equations, and the Rayleigh-Ritz method is utilized to calculate the natural frequencies of the system. The results show that the natural frequencies are affected by the porosity volume fraction, constituent volume fraction, and thermal load. Moreover,the natural frequencies obtained from the LTR have insignificant differences compared with those from the NLTR. Due to the calculation complexity of the NLTR, we propose that it is reasonable to replace it by its linear counterpart for the analysis of thin porous FGM cylindrical shells. The present results are verified in comparison with the published ones in the literature.
基金Project supported by the National Natural Science Foundation of China(No.11672071)the Fundamental Research Funds for the Central Universities(No.N170504023)
文摘The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into account. Based on the nonlocal elasticity theory and Donnell's nonlinear shell theory, the nonlinear governing equations and the corresponding boundary conditions are derived by employing Hamilton's principle. Then,the Galerkin method is used to transform the governing equations into a set of ordinary differential equations, and subsequently, the multiple-scale method is used to obtain an approximate analytical solution. Finally, an extensive parametric study is conducted to examine the effects of the nonlocal parameter, the external electric potential, the temperature rise, and the Winkler-Pasternak foundation parameters on the nonlinear vibration characteristics of circular cylindrical piezoelectric nanoshells.
文摘The trend of distance learning education has increased year by year because of the rapid advancement of information and communication technologies. Distance learning system can be regarded as one of ubiquitous computing applications since the learners can study anywhere even in mobile environments. However, the instructor cannot know if the learners comprehend the lecture or not since each learner is physically isolated. Therefore, a framework which detects the learners’ concentration condition is required. If a distance learning system obtains the information that many learners are not concentrated on the class due to the incomprehensible lecture style, the instructor can perceive it through the system and change the presentation strategy. This is a context-aware technology which is widely used for ubiquitous computing services. In this paper, an efficient distance learning system, which accurately detects learners’ concentration condition during a class, is proposed. The proposed system uses multiple biological information which are learners’ eye movement metrics, i.e. fixation counts, fixation rate, fixation duration and average saccade length obtained by an eye tracking system. The learners’ concentration condition is classified by using machine learning techniques. The proposed system has performed the detection accuracy of 90.7% when Multilayer Perceptron is used as a classifier. In addition, the effectiveness of the proposed eye metrics has been confirmed. Furthermore, it has been clarified that the fixation duration is the most important eye metric among the four metrics based on the investigation of evaluation experiment.
基金This article contributes to the project"Systematic multi-scale modeling and analysis for geophysical flow"of the Collaborative Research Center TRR 181"Energy Transfers in Atmosphere and Ocean"funded by the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)under project number 274762653.
文摘In this article,we consider a fully nonlinear partial differential equation which can be expressed as a sum of two Monge-Ampere operators acting in different two-dimensional coordinate sections.This equation is elliptic,for example,in the class of convex functions.We show that the notion of Monge-Ampere measures and Aleksandrov generalized solutions extends to this equation,subject to a weaker notion of convexity which we call bi-planar convexity.While the equation is also elliptic in the class of bi-planar convex functions,the contrary is not necessarily true.This is a substantial difference compared to the classical Monge-Ampere equation where ellipticity and convexity coincide.We provide explicit counter-examples:classical solutions to the bi-planar equation that satisfy the ellipticity condition but are not generalized solutions in the sense introduced.We conclude that the concept of generalized solutions based on convexity arguments is not a natural setting for the bi-planar equation.
