BL10U2 is an undulator-based macromolecular crystallography(MX)beamline located at the 3.5-GeV Shanghai Synchrotron Radiation Facility.BL10U2 is specifically designed for conducting routine and biosafety level-2(BSL-2...BL10U2 is an undulator-based macromolecular crystallography(MX)beamline located at the 3.5-GeV Shanghai Synchrotron Radiation Facility.BL10U2 is specifically designed for conducting routine and biosafety level-2(BSL-2)MX experiments utilizing high-flux tunable X-rays with energies from 7 to 18 keV,providing a beam spot size of 20μm(horizontal)×10μm(vertical)at the sample point.Certification by the Shanghai Pudong Municipal Health Commission confirmed the capability to perform BSL-2 MX experiments.The beamline is currently equipped with an Eiger X 16 M detector and two newly developed in-house high-precision diffractometers that can be switched to perform conventional or in situ crystal diffraction experiments.An automatic sample changer developed in-house allows fast sample exchange in less than 30 s,supporting high-throughput MX experimentation and rapid crystal screening.Data collection from both the diffractometer and detector was controlled by an in-house developed data collection software(Finback)with a user-friendly interface for convenient operation.This study presents a comprehensive overview of the facilities,experimental methods,and performance characteristics of the BL10U2 beamline.展开更多
Macromolecular crystallography beamline BL17U1 at the Shanghai Synchrotron Radiation Facility has been relocated,upgraded,and given a new ID(BL02U1).It now delivers X-rays in the energy range of 6–16 keV,with a focus...Macromolecular crystallography beamline BL17U1 at the Shanghai Synchrotron Radiation Facility has been relocated,upgraded,and given a new ID(BL02U1).It now delivers X-rays in the energy range of 6–16 keV,with a focused beam of 11.6μm×4.8μm and photon flux greater than 1012 phs/s.The high credibility and stability of the beam and good timing synchronization of the equipment significantly improve the experimental efficiency.Since June 2021,when it officially opened to users,over 4200 h of beamtime have been provided to over 200 research groups to collect data at the beamline.Its good performance and stable operation have led to the resolution of several structures based on data collected at the beamline.展开更多
Workers who conduct regular facility inspections in radioactive environments will inevitably be affected by radiation.Therefore,it is important to optimize the inspection path to ensure that workers are exposed to the...Workers who conduct regular facility inspections in radioactive environments will inevitably be affected by radiation.Therefore,it is important to optimize the inspection path to ensure that workers are exposed to the least amount of radiation.This study proposes a discrete Rao-combined artificial bee colony(ABC)algorithm for planning inspection paths with minimum exposure doses in radioactive environments with obstacles.In this algorithm,retaining the framework of the traditional ABC algorithm,we applied the directional solution update rules of Rao algorithms at the employed bee stage and onlooker bee stage to increase the exploitation ability of the algorithm and implement discretion using the swap operator and swap sequence.To increase the randomness of solution generation,the chaos algorithm was used at the initialization stage.The K-opt operation technique was introduced at the scout bee stage to increase the exploration ability of the algorithm.For path planning in an environment with complex structural obstacles,an obstacle detour technique using a recursive algorithm was applied.To evaluate the performance of the proposed algorithm,we performed experimental simulations in three hypothetical environments and compared the results with those of improved particle swarm optimization,chaos particle swarm optimization,improved ant colony optimization,and discrete Rao’s algorithms.The experimental results show the high performance of the proposed discrete Rao-combined ABC algorithm and its obstacle detour capability.展开更多
The diseases of sweet cherry caused by viruses and viroids have occurred in the main cherry producing areas of China and are increasing year by year, which has become an important factor affecting the yield and qualit...The diseases of sweet cherry caused by viruses and viroids have occurred in the main cherry producing areas of China and are increasing year by year, which has become an important factor affecting the yield and quality of sweet cherry. For this reason, this paper elaborated the prevention and countermeasures of virus diseases from six aspects, including soil treatment, cultivation of disease-free seedlings, prevention of disease and pest damage, reasonable pruning, water management, and treatment of virus diseases, in order to provide technical guidance for the disease resistance, high quality and high yield of facility cherry, as well as information reference for the further improvement of the technical system of virus disease prevention and cultivation of facility cherry.展开更多
With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were a...With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.展开更多
The differential evolution algorithm is an evolutionary algorithm for global optimization and the un-capacitated facility location problem (UFL) is one of the classic NP-Hard problems. In this paper, combined with the...The differential evolution algorithm is an evolutionary algorithm for global optimization and the un-capacitated facility location problem (UFL) is one of the classic NP-Hard problems. In this paper, combined with the specific characteristics of the UFL problem, we introduce the activation function to the algorithm for solving UFL problem and name it improved adaptive differential evolution algorithm (IADEA). Next, to improve the efficiency of the algorithm and to alleviate the problem of being stuck in a local optimum, an adaptive operator was added. To test the improvement of our algorithm, we compare the IADEA with the basic differential evolution algorithm by solving typical instances of UFL problem respectively. Moreover, to compare with other heuristic algorithm, we use the hybrid ant colony algorithm to solve the same instances. The computational results show that IADEA improves the performance of the basic DE and it outperforms the hybrid ant colony algorithm.展开更多
[Objective] The aim was to establish a set of soilless cultivation and management method of facility strawberry cultivation in the south of China.[Method] In the research,strawberry species,substrate formulae,cultivat...[Objective] The aim was to establish a set of soilless cultivation and management method of facility strawberry cultivation in the south of China.[Method] In the research,strawberry species,substrate formulae,cultivation modes and nutri ent solutions were selected and optimized.[Result] Three-dimensional strawberry cultivation was much suitable for Frandy,Hongbao and Gumei No.1; substrate with coconut shred-mushroom residue-peat soil ratio at 2∶2∶1 was the optimal; the treatment C3,containing Ca（NO3）2·4H2O,KNO3,（NH4）2HPO4,MgSO4·7H2O,and NH4NO3 at 280,303,62,246 and 80 mg/L,promoted strawberry growth,and the cultivated strawberry was large and thick in leaves,thick in stem,dark green in leaf color,with best fruit yield and quality.Among three cultivation modes,the density,space use ratio and yield in the treatment with PVC pipes in A-shape were all higher and the strawberry was easier and more convenient for picking.[Conclusion] The research provides references for soilless cultivation of strawberry in the south of China.展开更多
First a remanufactming logistics network is con- structed, in which the structure of both the forward logistics and the reverse logistics are of two levels and all the logistics facilities are capacitated. Both the re...First a remanufactming logistics network is con- structed, in which the structure of both the forward logistics and the reverse logistics are of two levels and all the logistics facilities are capacitated. Both the remanufactming products and the new products can be used to meet the demands of customers. Moreover, it is assumed that homogeneous facilities can be designed together into integrated ones, based on which a mixed integer nonlinear programming （MINLP） facility location model of the remanufacturing logistics network with six types of facilities to be sited is built. Then an algorithm based on enumeration for the model is given. The feasible combinations of binary variables are searched by enumeration, and the remaining sub-problems are solved by the LP solver. Finally, the validities of the model and the algorithm are illustrated by means of an example. The result of the sensitivity analysis of parameters indicates that the integration of homogeneous facilities may influence the optimal solution of the problem to a certain degree.展开更多
Micro-turbine engine has no enough space for measuring impeller characteristics,so the design and the construction of a new test facility of micro-turbo-machinery are presented for micro-centrifugal compressors and ra...Micro-turbine engine has no enough space for measuring impeller characteristics,so the design and the construction of a new test facility of micro-turbo-machinery are presented for micro-centrifugal compressors and radial turbines.The facility is used for the full speed compressor test and the long duration hot turbine test.To rapidly adjust the testing condition,all regulations of the operating state are automatically completed by the control system.The facility is also used for testing the impeller performance with a series of diameter from 55 mm to 180 mm as a result of the modular design.A thermal protection system is designed to avoid the heat distortion caused by the high turbine inlet temperature over 1 100 K and provide a proper experimental environment for the electronic components.A photoelectric torque transducer with the accuracy of 1% is designed to measure the torque of rigid shaft at a high speed of 125 000 r/min.The designing techniques for micro-turbo-machineries are verified by the impeller testing of the facility.展开更多
To smooth the correlation process from bio-virus diffusion to emergency relief response,the Gaussian plume model is used to describe the diffusion of dangerous sources,where the bio-virus concentration at any given po...To smooth the correlation process from bio-virus diffusion to emergency relief response,the Gaussian plume model is used to describe the diffusion of dangerous sources,where the bio-virus concentration at any given point in affected areas can be calculated.And the toxic load rule is introduced to define the borderline of the dangerous area at different levels.Combined with this,different emergency levels of different demand points in dangerous areas are confirmed using fuzzy clustering,which allows demand points at the same emergency level to cluster in a group.Some effective emergency relief centers are chosen from the candidate hospitals which are located in different emergency level affected areas by set covering.Bioterrorism experiments which were conducted in Nanjing,Jiangsu province are simulated,and the results indicate that the novel method can be used efficiently by decision makers during an actual anti-bioterrorism relief.展开更多
Layout design problem is to determine a suitable arrangement for the departments so that the total costs associated with the flow among departments become least. Single Row Facility Layout Problem, SRFLP, is one of &l...Layout design problem is to determine a suitable arrangement for the departments so that the total costs associated with the flow among departments become least. Single Row Facility Layout Problem, SRFLP, is one of </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">the </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">layout problems that have many practical applications. This problem and its specific scenarios are often used to model many of the raised issues in the field of facility location. SRFLP is an arrangement of </span><i><span style="font-family:Verdana;">n</span></i><span style="font-family:Verdana;"> departments with a specified length in a straight line so that the sum of the weighted distances between the pairs of departments is minimized. This problem is NP-hard. In this paper, first, a lower bound for a special case of SRFLP is presented. Then, a general </span><span style="font-family:Verdana;">case of SRFLP is presented in which some new and real assumptions are added to generate more practical model. Then a lower bound, as well as an algorithm, is proposed for solving the model. Experimental results on some instances in literature show the efficiency of our algorithm.展开更多
The protein complex crystallographic beamline BL19U1 at the Shanghai Synchrotron Radiation Facility is one of the five beamlines dedicated to protein sciences operated by National Facility for Protein Science(Shanghai...The protein complex crystallographic beamline BL19U1 at the Shanghai Synchrotron Radiation Facility is one of the five beamlines dedicated to protein sciences operated by National Facility for Protein Science(Shanghai,China).The beamline,which features a small-gap invacuum undulator,has been officially open to users since March 2015.This beamline delivers X-ray in the energy range 7–15 keV.With its high flux,low divergence beam and a large active area detector,BL19U1 is designed for proteins with large molecular weight and large crystallographic unit cell dimensions.Good performance and stable operation of the beamline have allowed the number of Protein Data Bank(PDB)depositions and the number of articles published based on data collected at this beamline to increase steadily.To date,over 300 research groups have collected data at the beamline.More than 600 PDB entries have been deposited at the PDB(www.pdb.org).More than 300 papers have been published that include data collected at the beamline,including 21 research articles published in the top-level journals Cell,Nature,and Science.展开更多
Facility layout selection is a multi-criteria decision making (MCDM) problem,since it has a strategic impact on the efficiency of manufacturing system.In view of the interdependency among selection criteria,analytic n...Facility layout selection is a multi-criteria decision making (MCDM) problem,since it has a strategic impact on the efficiency of manufacturing system.In view of the interdependency among selection criteria,analytic network process (ANP) is proposed to analyze the structure of the facility layout selection problem and determine the weights for each criterion.A network structure is constructed that shows all elements and clusters and their interactions.Limit priorities are also calculated which help decision maker evaluate the relative importance among criterion in the alternative selection process.Moreover,a hybrid MCDM approach that employs ANP and technique for order preference by similarity to an ideal solution (TOPSIS)method to rank the optimal facility layout alternatives.Finally,an application of a new aeronautic component assembly workshop facility layout selection is conducted.To further illustrate the advantage of the proposed approach,the difference between ANP-TOPSIS and AHP-TOPSIS methods are compared and discussed.Results have demonstrated the effectiveness and feasibility of the proposed method.展开更多
Heavy-ion collisions are powerful tools for studying hypernuclear physics.We develop a dynamical coalescence model coupled with an ART model(version1.0) to study the production rates of light nuclear clusters and hype...Heavy-ion collisions are powerful tools for studying hypernuclear physics.We develop a dynamical coalescence model coupled with an ART model(version1.0) to study the production rates of light nuclear clusters and hypernuclei in heavy-ion reactions,for instance,the deuteron(d),triton(t),helium(~3He),and hypertriton(_A^3H)in minimum bias(0-80%centrality)~6Li+^(12)C reactions at beam energy of 3.5A GeV.The penalty factor for light clusters is extracted from the yields,and the distributions of 0 angle of particles,which provide direct suggesetions about the location of particle detectors in the near future facility-High Intensity heavy-ion Accelerator Facility(HIAF) are investigated.Our calculation demonstrates that HIAF is suitable for studying hypernuclear physics.展开更多
A 100 kJ-level laser facility has been designed to study inertial confinement fusion physics in China.This facility incorporates various diagnostic techniques,including optical,x-ray imaging,x-ray spectrum,and fusion ...A 100 kJ-level laser facility has been designed to study inertial confinement fusion physics in China.This facility incorporates various diagnostic techniques,including optical,x-ray imaging,x-ray spectrum,and fusion product diagnostics,as well as general diagnostics assistance systems and central control and data acquisition systems.This paper describes recent developments in diagnostics at the facility.展开更多
Beam lifetime is dominated by Touschek scattering at the Shanghai Synchrotron Radiation Facility(SSRF).Touschek loss rate is affected by probability for scattering beyond the RF acceptance and the volume charge densit...Beam lifetime is dominated by Touschek scattering at the Shanghai Synchrotron Radiation Facility(SSRF).Touschek loss rate is affected by probability for scattering beyond the RF acceptance and the volume charge density of the bench.In the phaseⅡupgrade of the SSRF,a third harmonic superconducting cavity will be used to enhance the Touschek lifetime by lengthening the bunches.The Touschek lifetime improvement factor is affected by the voltage of a harmonic cavity.To stabilize the cavity voltage,a tuning control system was designed to control it.The design of the tuning control system was based on the SSRF third-generation low-level RF control system.Some hardware and specialized algorithms were redesigned to fit the harmonic cavity control.The design of the tuning control system is complete,and the control system has been tested.The test result shows that the fluctuation of amplitude is<±0.34%within 1.5 h,which satisfies the stability requirement.展开更多
We report the design of a wide-range energy material beamline(E-line) with multiple experimental techniques at the Shanghai Synchrotron Radiation Facility.The undulators consisted of an elliptically polarizing undulat...We report the design of a wide-range energy material beamline(E-line) with multiple experimental techniques at the Shanghai Synchrotron Radiation Facility.The undulators consisted of an elliptically polarizing undulator and in-vacuum undulator that generate the soft and hard X-rays, respectively. The beamline covered a wide energy range from 130 to 18 ke V with both a high photon flux([ 10^(12) phs/s with exit silt 30 lm in soft X-ray and [ 5 9 10^(12) phs/s in hard X-ray within 0.1%BW bandwidth) and promising resolving power(maximum E/DE [ 15,000 in soft X-ray with exit silt 30 lm and [6000 in hard X-ray). Moreover, the beam spots from the soft and hard X-rays were focused to the same sample position with a high overlap ratio, so that the surfaces, interfaces, and bulk properties were characterized in situ by changing the probing depth.展开更多
An S-band high-gradient accelerating structure is designed for a proton therapy linear accelerator(linac)to accommodate the new development of compact,singleroom facilities and ultra-high dose rate(FLASH)radiotherapy....An S-band high-gradient accelerating structure is designed for a proton therapy linear accelerator(linac)to accommodate the new development of compact,singleroom facilities and ultra-high dose rate(FLASH)radiotherapy.To optimize the design,an efficient optimization scheme is applied to improve the simulation efficiency.An S-band accelerating structure with 2856 MHz is designed with a low beta of 0.38,which is a difficult structure to achieve for a linac accelerating proton particles from 70 to 250 MeV,as a high gradient up to 50 MV/m is required.A special design involving a dual-feed coupler eliminates the dipole field effect.This paper presents all the details pertaining to the design,fabrication,and cold test results of the S-band high-gradient accelerating structure.展开更多
Significant electromagnetic pulses （EMP） can be generated by the intensive laser irradiating solid targets in inertial confinement fusion （ICF）. To evaluate the EMP intensity and distribution in and outside the la...Significant electromagnetic pulses （EMP） can be generated by the intensive laser irradiating solid targets in inertial confinement fusion （ICF）. To evaluate the EMP intensity and distribution in and outside the laser chamber, we designed and fabricated a discone antenna with ultra-wide bands of over 10 GHz. The return loss （Sn parameter） of this antenna was below -10 dB and could even achieve under -30 dB at 3.1 GHz. The EMP intensity in this study at 80 cm and 40 cm away from the target chamber center （TCC） reached 400 kV/m and 2000 kV/m. The current results are expected to offer preliminary information to study physics regarding laser plasma interactions and will also lay experimental foundation for EMI shielding design to protect various diagnostics.展开更多
This study aims at identifying crash-influencing factors by facility type of Nagoya Urban Expressway, considering the interaction of geometry, traffic flow, and ambient conditions. Crash rate （CR） model is firstly d...This study aims at identifying crash-influencing factors by facility type of Nagoya Urban Expressway, considering the interaction of geometry, traffic flow, and ambient conditions. Crash rate （CR） model is firstly developed separately at four facility types： basic, merge, and diverge segments and sharp curve. Traffic flows are thereby categorized, and based on the traffic categories, the significances of factors affecting crashes are analyzed by principal component analysis. The results reveal that, the CR at merge segment is significantly higher than those at basic and diverge segments in uncongested flow, while the value is not significantly different at the three facility types in congested flow. In both un- and congested flows, sharp curve has the worst safety performance in view of its highest CR. Regarding influencing factors, geometric design and traffic flow are most significant in un- and congested flows, respectively. As mainline flow increases, the effect of merging ratio affecting crash is on the rise at basic and merge segments as opposed to the decreasing significance of diverging ratio at diverge segment. Mean- while, longer acceleration and deceleration lanes are adverse to safety in uncongested flow, while shorter acceleration and deceleration lanes are adverse in congested flow. Due to its special geometric design, crashes at sharp curve are highly associated with the large centrifugal force and heavy restricted visibility.展开更多
基金supported by the SSRF Phase-II projectNatural Science Foundation of Shanghai(Nos.21ZR1471800 and 23ZR1471200)National Natural Science Foundation of China(No.12005281)。
文摘BL10U2 is an undulator-based macromolecular crystallography(MX)beamline located at the 3.5-GeV Shanghai Synchrotron Radiation Facility.BL10U2 is specifically designed for conducting routine and biosafety level-2(BSL-2)MX experiments utilizing high-flux tunable X-rays with energies from 7 to 18 keV,providing a beam spot size of 20μm(horizontal)×10μm(vertical)at the sample point.Certification by the Shanghai Pudong Municipal Health Commission confirmed the capability to perform BSL-2 MX experiments.The beamline is currently equipped with an Eiger X 16 M detector and two newly developed in-house high-precision diffractometers that can be switched to perform conventional or in situ crystal diffraction experiments.An automatic sample changer developed in-house allows fast sample exchange in less than 30 s,supporting high-throughput MX experimentation and rapid crystal screening.Data collection from both the diffractometer and detector was controlled by an in-house developed data collection software(Finback)with a user-friendly interface for convenient operation.This study presents a comprehensive overview of the facilities,experimental methods,and performance characteristics of the BL10U2 beamline.
基金supported by the National Key Research and Development Program of China(No.2021YFC2301405)the National Natural Science Foundation of China(No.31971121)Shanghai Science and Technology Plan Project(No.21ZR14718)。
文摘Macromolecular crystallography beamline BL17U1 at the Shanghai Synchrotron Radiation Facility has been relocated,upgraded,and given a new ID(BL02U1).It now delivers X-rays in the energy range of 6–16 keV,with a focused beam of 11.6μm×4.8μm and photon flux greater than 1012 phs/s.The high credibility and stability of the beam and good timing synchronization of the equipment significantly improve the experimental efficiency.Since June 2021,when it officially opened to users,over 4200 h of beamtime have been provided to over 200 research groups to collect data at the beamline.Its good performance and stable operation have led to the resolution of several structures based on data collected at the beamline.
文摘Workers who conduct regular facility inspections in radioactive environments will inevitably be affected by radiation.Therefore,it is important to optimize the inspection path to ensure that workers are exposed to the least amount of radiation.This study proposes a discrete Rao-combined artificial bee colony(ABC)algorithm for planning inspection paths with minimum exposure doses in radioactive environments with obstacles.In this algorithm,retaining the framework of the traditional ABC algorithm,we applied the directional solution update rules of Rao algorithms at the employed bee stage and onlooker bee stage to increase the exploitation ability of the algorithm and implement discretion using the swap operator and swap sequence.To increase the randomness of solution generation,the chaos algorithm was used at the initialization stage.The K-opt operation technique was introduced at the scout bee stage to increase the exploration ability of the algorithm.For path planning in an environment with complex structural obstacles,an obstacle detour technique using a recursive algorithm was applied.To evaluate the performance of the proposed algorithm,we performed experimental simulations in three hypothetical environments and compared the results with those of improved particle swarm optimization,chaos particle swarm optimization,improved ant colony optimization,and discrete Rao’s algorithms.The experimental results show the high performance of the proposed discrete Rao-combined ABC algorithm and its obstacle detour capability.
基金Supported by Class A Project of Scientific Research Development Program of Colleges and Universities in Shandong Province (J17KA155)。
文摘The diseases of sweet cherry caused by viruses and viroids have occurred in the main cherry producing areas of China and are increasing year by year, which has become an important factor affecting the yield and quality of sweet cherry. For this reason, this paper elaborated the prevention and countermeasures of virus diseases from six aspects, including soil treatment, cultivation of disease-free seedlings, prevention of disease and pest damage, reasonable pruning, water management, and treatment of virus diseases, in order to provide technical guidance for the disease resistance, high quality and high yield of facility cherry, as well as information reference for the further improvement of the technical system of virus disease prevention and cultivation of facility cherry.
基金Supported by Project of Shandong Institute of Modern Agriculture of Zhejiang University for Serving Local Economic Development (ZDNY-2020-FWLY2006)。
文摘With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.
文摘The differential evolution algorithm is an evolutionary algorithm for global optimization and the un-capacitated facility location problem (UFL) is one of the classic NP-Hard problems. In this paper, combined with the specific characteristics of the UFL problem, we introduce the activation function to the algorithm for solving UFL problem and name it improved adaptive differential evolution algorithm (IADEA). Next, to improve the efficiency of the algorithm and to alleviate the problem of being stuck in a local optimum, an adaptive operator was added. To test the improvement of our algorithm, we compare the IADEA with the basic differential evolution algorithm by solving typical instances of UFL problem respectively. Moreover, to compare with other heuristic algorithm, we use the hybrid ant colony algorithm to solve the same instances. The computational results show that IADEA improves the performance of the basic DE and it outperforms the hybrid ant colony algorithm.
基金Supported by National Natural Science Foundation of China(31101534)Youth Foundation of Tutorial System,Fujian Academy of Agricultural Sciences(2013DQB-8)~~
文摘[Objective] The aim was to establish a set of soilless cultivation and management method of facility strawberry cultivation in the south of China.[Method] In the research,strawberry species,substrate formulae,cultivation modes and nutri ent solutions were selected and optimized.[Result] Three-dimensional strawberry cultivation was much suitable for Frandy,Hongbao and Gumei No.1; substrate with coconut shred-mushroom residue-peat soil ratio at 2∶2∶1 was the optimal; the treatment C3,containing Ca（NO3）2·4H2O,KNO3,（NH4）2HPO4,MgSO4·7H2O,and NH4NO3 at 280,303,62,246 and 80 mg/L,promoted strawberry growth,and the cultivated strawberry was large and thick in leaves,thick in stem,dark green in leaf color,with best fruit yield and quality.Among three cultivation modes,the density,space use ratio and yield in the treatment with PVC pipes in A-shape were all higher and the strawberry was easier and more convenient for picking.[Conclusion] The research provides references for soilless cultivation of strawberry in the south of China.
基金The National Natural Science Foundation of China(No.70472033).
文摘First a remanufactming logistics network is con- structed, in which the structure of both the forward logistics and the reverse logistics are of two levels and all the logistics facilities are capacitated. Both the remanufactming products and the new products can be used to meet the demands of customers. Moreover, it is assumed that homogeneous facilities can be designed together into integrated ones, based on which a mixed integer nonlinear programming （MINLP） facility location model of the remanufacturing logistics network with six types of facilities to be sited is built. Then an algorithm based on enumeration for the model is given. The feasible combinations of binary variables are searched by enumeration, and the remaining sub-problems are solved by the LP solver. Finally, the validities of the model and the algorithm are illustrated by means of an example. The result of the sensitivity analysis of parameters indicates that the integration of homogeneous facilities may influence the optimal solution of the problem to a certain degree.
基金Supported by the National Natural Science Foundation of China(50576034)~~
文摘Micro-turbine engine has no enough space for measuring impeller characteristics,so the design and the construction of a new test facility of micro-turbo-machinery are presented for micro-centrifugal compressors and radial turbines.The facility is used for the full speed compressor test and the long duration hot turbine test.To rapidly adjust the testing condition,all regulations of the operating state are automatically completed by the control system.The facility is also used for testing the impeller performance with a series of diameter from 55 mm to 180 mm as a result of the modular design.A thermal protection system is designed to avoid the heat distortion caused by the high turbine inlet temperature over 1 100 K and provide a proper experimental environment for the electronic components.A photoelectric torque transducer with the accuracy of 1% is designed to measure the torque of rigid shaft at a high speed of 125 000 r/min.The designing techniques for micro-turbo-machineries are verified by the impeller testing of the facility.
基金The National Natural Science Foundation of China(No.70671021)the National Key Technology R&D Program of China during the 11th Five-Year Plan Period(No.2006BAH02A06)
文摘To smooth the correlation process from bio-virus diffusion to emergency relief response,the Gaussian plume model is used to describe the diffusion of dangerous sources,where the bio-virus concentration at any given point in affected areas can be calculated.And the toxic load rule is introduced to define the borderline of the dangerous area at different levels.Combined with this,different emergency levels of different demand points in dangerous areas are confirmed using fuzzy clustering,which allows demand points at the same emergency level to cluster in a group.Some effective emergency relief centers are chosen from the candidate hospitals which are located in different emergency level affected areas by set covering.Bioterrorism experiments which were conducted in Nanjing,Jiangsu province are simulated,and the results indicate that the novel method can be used efficiently by decision makers during an actual anti-bioterrorism relief.
文摘Layout design problem is to determine a suitable arrangement for the departments so that the total costs associated with the flow among departments become least. Single Row Facility Layout Problem, SRFLP, is one of </span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">the </span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">layout problems that have many practical applications. This problem and its specific scenarios are often used to model many of the raised issues in the field of facility location. SRFLP is an arrangement of </span><i><span style="font-family:Verdana;">n</span></i><span style="font-family:Verdana;"> departments with a specified length in a straight line so that the sum of the weighted distances between the pairs of departments is minimized. This problem is NP-hard. In this paper, first, a lower bound for a special case of SRFLP is presented. Then, a general </span><span style="font-family:Verdana;">case of SRFLP is presented in which some new and real assumptions are added to generate more practical model. Then a lower bound, as well as an algorithm, is proposed for solving the model. Experimental results on some instances in literature show the efficiency of our algorithm.
文摘The protein complex crystallographic beamline BL19U1 at the Shanghai Synchrotron Radiation Facility is one of the five beamlines dedicated to protein sciences operated by National Facility for Protein Science(Shanghai,China).The beamline,which features a small-gap invacuum undulator,has been officially open to users since March 2015.This beamline delivers X-ray in the energy range 7–15 keV.With its high flux,low divergence beam and a large active area detector,BL19U1 is designed for proteins with large molecular weight and large crystallographic unit cell dimensions.Good performance and stable operation of the beamline have allowed the number of Protein Data Bank(PDB)depositions and the number of articles published based on data collected at this beamline to increase steadily.To date,over 300 research groups have collected data at the beamline.More than 600 PDB entries have been deposited at the PDB(www.pdb.org).More than 300 papers have been published that include data collected at the beamline,including 21 research articles published in the top-level journals Cell,Nature,and Science.
基金supported by the National Natural Science Foundation of China (No.51575274)the National Defense Basic Scientific Research Program of China (No.JCKY2016605B006)the Key Research and Development Project of Jiangxi Province in China (No.20161ACE50004)
文摘Facility layout selection is a multi-criteria decision making (MCDM) problem,since it has a strategic impact on the efficiency of manufacturing system.In view of the interdependency among selection criteria,analytic network process (ANP) is proposed to analyze the structure of the facility layout selection problem and determine the weights for each criterion.A network structure is constructed that shows all elements and clusters and their interactions.Limit priorities are also calculated which help decision maker evaluate the relative importance among criterion in the alternative selection process.Moreover,a hybrid MCDM approach that employs ANP and technique for order preference by similarity to an ideal solution (TOPSIS)method to rank the optimal facility layout alternatives.Finally,an application of a new aeronautic component assembly workshop facility layout selection is conducted.To further illustrate the advantage of the proposed approach,the difference between ANP-TOPSIS and AHP-TOPSIS methods are compared and discussed.Results have demonstrated the effectiveness and feasibility of the proposed method.
基金supported in part by the Major State Basic Research Development Program in China(Nos.2014CB845401 and2015CB856904)the National Natural Science Foundation of China(Nos.11421505,11520101004,11275250,11322547 and U1232206)Key Program of CAS for the Frontier Science(No.QYZDJ-SSW-SLH002)
文摘Heavy-ion collisions are powerful tools for studying hypernuclear physics.We develop a dynamical coalescence model coupled with an ART model(version1.0) to study the production rates of light nuclear clusters and hypernuclei in heavy-ion reactions,for instance,the deuteron(d),triton(t),helium(~3He),and hypertriton(_A^3H)in minimum bias(0-80%centrality)~6Li+^(12)C reactions at beam energy of 3.5A GeV.The penalty factor for light clusters is extracted from the yields,and the distributions of 0 angle of particles,which provide direct suggesetions about the location of particle detectors in the near future facility-High Intensity heavy-ion Accelerator Facility(HIAF) are investigated.Our calculation demonstrates that HIAF is suitable for studying hypernuclear physics.
基金This work was performed under the auspices of the National Key R&D Program of China,No.2017YFA0403300National Natural Science Foundation of China under Contract Nos.11805184,11805178,11805185+2 种基金Presidential Foundation of China Academy of Engineering Physics,No.YZJJLX2019011Science Challenging Project,No.TZ2016001Laser Fusion Research Center Funds for Young Talents,No.RCFPD4-2020-1.
文摘A 100 kJ-level laser facility has been designed to study inertial confinement fusion physics in China.This facility incorporates various diagnostic techniques,including optical,x-ray imaging,x-ray spectrum,and fusion product diagnostics,as well as general diagnostics assistance systems and central control and data acquisition systems.This paper describes recent developments in diagnostics at the facility.
文摘Beam lifetime is dominated by Touschek scattering at the Shanghai Synchrotron Radiation Facility(SSRF).Touschek loss rate is affected by probability for scattering beyond the RF acceptance and the volume charge density of the bench.In the phaseⅡupgrade of the SSRF,a third harmonic superconducting cavity will be used to enhance the Touschek lifetime by lengthening the bunches.The Touschek lifetime improvement factor is affected by the voltage of a harmonic cavity.To stabilize the cavity voltage,a tuning control system was designed to control it.The design of the tuning control system was based on the SSRF third-generation low-level RF control system.Some hardware and specialized algorithms were redesigned to fit the harmonic cavity control.The design of the tuning control system is complete,and the control system has been tested.The test result shows that the fluctuation of amplitude is<±0.34%within 1.5 h,which satisfies the stability requirement.
基金supported by the National Development and Reform Commission(NDRC) of Chinathe National Natural Science Foundation of China(No.11505280)+1 种基金the Shanghai Youth Foundation(No.14YF1407500)the National Science Foundation of China(Nos.11475251,11225527)
文摘We report the design of a wide-range energy material beamline(E-line) with multiple experimental techniques at the Shanghai Synchrotron Radiation Facility.The undulators consisted of an elliptically polarizing undulator and in-vacuum undulator that generate the soft and hard X-rays, respectively. The beamline covered a wide energy range from 130 to 18 ke V with both a high photon flux([ 10^(12) phs/s with exit silt 30 lm in soft X-ray and [ 5 9 10^(12) phs/s in hard X-ray within 0.1%BW bandwidth) and promising resolving power(maximum E/DE [ 15,000 in soft X-ray with exit silt 30 lm and [6000 in hard X-ray). Moreover, the beam spots from the soft and hard X-rays were focused to the same sample position with a high overlap ratio, so that the surfaces, interfaces, and bulk properties were characterized in situ by changing the probing depth.
基金This work was supported by the Alliance of International Science Organizations(No.ANSO-CR-KP-2020-16).
文摘An S-band high-gradient accelerating structure is designed for a proton therapy linear accelerator(linac)to accommodate the new development of compact,singleroom facilities and ultra-high dose rate(FLASH)radiotherapy.To optimize the design,an efficient optimization scheme is applied to improve the simulation efficiency.An S-band accelerating structure with 2856 MHz is designed with a low beta of 0.38,which is a difficult structure to achieve for a linac accelerating proton particles from 70 to 250 MeV,as a high gradient up to 50 MV/m is required.A special design involving a dual-feed coupler eliminates the dipole field effect.This paper presents all the details pertaining to the design,fabrication,and cold test results of the S-band high-gradient accelerating structure.
基金supported by the Fundamental Research Funds for the Central Universities of China(No.ZYGX2015J108)National Natural Science Foundation of China(Nos.11575166 and 51581140)
文摘Significant electromagnetic pulses （EMP） can be generated by the intensive laser irradiating solid targets in inertial confinement fusion （ICF）. To evaluate the EMP intensity and distribution in and outside the laser chamber, we designed and fabricated a discone antenna with ultra-wide bands of over 10 GHz. The return loss （Sn parameter） of this antenna was below -10 dB and could even achieve under -30 dB at 3.1 GHz. The EMP intensity in this study at 80 cm and 40 cm away from the target chamber center （TCC） reached 400 kV/m and 2000 kV/m. The current results are expected to offer preliminary information to study physics regarding laser plasma interactions and will also lay experimental foundation for EMI shielding design to protect various diagnostics.
基金support of Nagoya Expressway Public Corporation for the data provision
文摘This study aims at identifying crash-influencing factors by facility type of Nagoya Urban Expressway, considering the interaction of geometry, traffic flow, and ambient conditions. Crash rate （CR） model is firstly developed separately at four facility types： basic, merge, and diverge segments and sharp curve. Traffic flows are thereby categorized, and based on the traffic categories, the significances of factors affecting crashes are analyzed by principal component analysis. The results reveal that, the CR at merge segment is significantly higher than those at basic and diverge segments in uncongested flow, while the value is not significantly different at the three facility types in congested flow. In both un- and congested flows, sharp curve has the worst safety performance in view of its highest CR. Regarding influencing factors, geometric design and traffic flow are most significant in un- and congested flows, respectively. As mainline flow increases, the effect of merging ratio affecting crash is on the rise at basic and merge segments as opposed to the decreasing significance of diverging ratio at diverge segment. Mean- while, longer acceleration and deceleration lanes are adverse to safety in uncongested flow, while shorter acceleration and deceleration lanes are adverse in congested flow. Due to its special geometric design, crashes at sharp curve are highly associated with the large centrifugal force and heavy restricted visibility.
