The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study are...The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure.展开更多
The alpha–beta filter algorithm has been widely researched for various applications,for example,navigation and target tracking systems.To improve the dynamic performance of the alpha–beta filter algorithm,a new pred...The alpha–beta filter algorithm has been widely researched for various applications,for example,navigation and target tracking systems.To improve the dynamic performance of the alpha–beta filter algorithm,a new prediction learning model is proposed in this study.The proposed model has two main components:(1)the alpha–beta filter algorithm is the main prediction module,and(2)the learning module is a feedforward artificial neural network(FF‐ANN).Furthermore,the model uses two inputs,temperature sensor and humidity sensor data,and a prediction algorithm is used to predict actual sensor readings from noisy sensor readings.Using the novel proposed technique,prediction accuracy is significantly improved while adding the feed‐forward backpropagation neural network,and also reduces the root mean square error(RMSE)and mean absolute error(MAE).We carried out different experiments with different experimental setups.The proposed model performance was evaluated with the traditional alpha–beta filter algorithm and other algorithms such as the Kalman filter.A higher prediction accuracy was achieved,and the MAE and RMSE were 35.1%–38.2%respectively.The final proposed model results show increased performance when compared to traditional methods.展开更多
Cooling the PV surface in a Photovoltaic Thermal system is a pivotal operational aspect to be taken into account to achieve optimized values of performance parameters in a Photovoltaic Thermal System.The experimental ...Cooling the PV surface in a Photovoltaic Thermal system is a pivotal operational aspect to be taken into account to achieve optimized values of performance parameters in a Photovoltaic Thermal System.The experimental design used in this study facilitates the flow of varying concentrations of Zn-water nanofluid in serpentine copper tubing installed at the rear of the PV panel thereby preventing the PV surface temperature from increasing beyond the threshold value at which a decrease in electrical efficiency starts to occur.This fusion of solar thermal with PV devices leads to better electrical and thermal efficiency values resulting in decreased cell degradation over time and maximization of the lifespan of the PV module and the energy output from the PV system.Due to the superior thermal heat properties of nanofluids,their usage in such systems has become increasingly widespread.Life cycle metrics which include Energy Payback period,Energy Production Factor and life cycle conversion efficiency were evaluated for the PVT system by exhaustively chalking fundamental parameters such as embodied energy of the PVT setup and the total energy output from the PVT system.This research aims to be a major milestone in the evolutionary journey of Photovoltaic Thermal modules by guiding the engineers working on the theory,design and implementation of PVT systems towards its economic feasibility,environmental impact and energy sustainability.展开更多
Background: Several circumstances and conditions lead to UGIB. The commonest among them peptic ulcer to an approximation of 50% in cases. The second major cause may be esoghageal varices and third is mallory-weis tear...Background: Several circumstances and conditions lead to UGIB. The commonest among them peptic ulcer to an approximation of 50% in cases. The second major cause may be esoghageal varices and third is mallory-weis tears. There are also other causes, which may include erosins, tumors and other malformations like arteriovenous. Methods: This was an observational retrospective study of all patients referred to endoscopy. The study exclusion criteria include all patients who had repeat endoscopies within one month of the previous endoscopy whereas all the patients with UGIB were included in this study. Results: We retrieved data of total 150 patients who had experienced upper gastrointestinal endoscopy during the selected time period covered in the study, March 2015 to February 2016. The mean age of the patients was 43.3 ± 13.80. 80 (53.3%) of the patients were male and 70 (46.7%) were females. Exploring more into UGIB causes the majority of patients were with esophageal varices 68 (45.3%) with male to female share was 2:1. The second most cause was esophagitis (n = 22, (14.67%)), the distribution of the cause was similar in male to female. Conclusion: We may conclude from our findings that the most common cause of UGIB is esophageal varices in our population.展开更多
The voluminous Choke Shield basalts and flood basalts are distributed in the central Ethiopian Plateau.They are tholeiitic in composition and have OIB-like geochemical features.The ca.23 Ma Choke Shield basalts have S...The voluminous Choke Shield basalts and flood basalts are distributed in the central Ethiopian Plateau.They are tholeiitic in composition and have OIB-like geochemical features.The ca.23 Ma Choke Shield basalts have SiO_(2)(47.1 wt.%-59.6 wt.%),MgO(1.01 wt.%-7.8 wt.%),Na_(2)O+K_(2)O(2.7 wt.%-8.4 wt.%),and display right inclined REE patterns((La/Yb)N=21.4-24.2) with enrichment of Nb,Ta,Zr,Hf and Pb in the primitive mantle-normalized trace element diagrams.They show low initial ^(87)Sr/^(86)Sr ratios(0.703 47-0.703 77) and high ε_(Nd)(t) values(+4.4 to+5.0).In comparison,the 24Ma high-Ti(HT1) flood basalts have SiO_(2)(38.9 wt.%-50.8 wt.%),MgO(3.9 wt.%-11.4 wt.%),Na_(2)O+K_(2)O(1.6 wt.%-5.8 wt.%), and display right inclined REE patterns((La/Yb)N=24-130.3) with enrichment of Nb,Ta,Zr,Hf,and Pb.They also show low initial ^(87)Sr/^(86)Sr ratios(0.703 30-0.704 44) and highε_(Nd)(t) values(+2.2 to+5.3).Both types of basalts were contaminated by minor crustal materials and underwent fractional crystallization of clinopyroxene,plagioclase,olivine,and minor Fe-Ti oxide.The Choke Shield basalts were generated by 1%-5% melting of garnet-spinel to phlogopite-bearing spinel lherzolite in a shallow zone of the mantle plume,while the flood basalts were formed by <20% melting of amphibole-bearing garnet to garnet-spinel lherzolite in a deeper zone of the same mantle plume.The mantle source beneath the central Ethiopian Plateau was significantly heterogeneous during the Tertiary.It was characterized by EMI and EMII end-members that were formed by the metasomatism of the different components.展开更多
Mucinous cystic tumor of the gallbladder is an extremely rare benign tumor,with potential for malignant degeneration.Mucinous cystic tumors of the cystic duct are divided into mucinous cystadenoma and mucinous cystade...Mucinous cystic tumor of the gallbladder is an extremely rare benign tumor,with potential for malignant degeneration.Mucinous cystic tumors of the cystic duct are divided into mucinous cystadenoma and mucinous cystadenocarcinoma.Currently,cystadenoma is generally considered to be a precancerous lesion of cystadenocarcinoma.At present,there are few cases reported worldwide,and there are no relevant guidelines for diagnosis and treatment of this disease.This article presents the collected clinical data of a patient with mucinous cystic tumor of the gallbladder who was admitted to the First Affiliated Hospital of Hunan Normal University,with the characteristics of the disease summarized in combination with a focused literature review.展开更多
基金financially supported by the Higher Education Commission of Pakistan (HEC) grant under National Research Program for Universities (NRPU) with No: (20-14681/NRPU/R&D/HEC/20212021)。
文摘The geological and geographical position of the Northwest Himalayas makes it a vulnerable area for mass movements particularly landslides and debris flows. Mass movements have had a substantial impact on the study area which is extending along Karakorum Highway(KKH) from Besham to Chilas. Intense seismicity, deep gorges, steep terrain and extreme climatic events trigger multiple mountain hazards along the KKH, among which debris flow is recognized as the most destructive geohazard. This study aims to prepare a field-based debris flow inventory map at a regional scale along a 200 km stretch from Besham to Chilas. A total of 117 debris flows were identified in the field, and subsequently, a point-based debris-flow inventory and catchment delineation were performed through Arc GIS analysis. Regional scale debris flow susceptibility and propagation maps were prepared using Weighted Overlay Method(WOM) and Flow-R technique sequentially. Predisposing factors include slope, slope aspect, elevation, Topographic Roughness Index(TRI), Topographic Wetness Index(TWI), stream buffer, distance to faults, lithology rainfall, curvature, and collapsed material layer. The dataset was randomly divided into training data(75%) and validation data(25%). Results were validated through the Receiver Operator Characteristics(ROC) curve. Results show that Area Under the Curve(AUC) using WOM model is 79.2%. Flow-R propagation of debris flow shows that the 13.15%, 22.94%, and 63.91% areas are very high, high, and low susceptible to debris flow respectively. The propagation predicated by Flow-R validates the naturally occurring debris flow propagation as observed in the field surveys. The output of this research will provide valuable input to the decision makers for the site selection, designing of the prevention system, and for the protection of current infrastructure.
基金supported by the Institute of Information&communications Technology Planning&Evaluation(IITP)grant funded by the Korea government(MSIT)(No.2020‐0‐01441,Artificial Intelligence Convergence Research Center(Chungnam National University))“Regional Innovation Strategy(RIS)”through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(2021RIS‐004).
文摘The alpha–beta filter algorithm has been widely researched for various applications,for example,navigation and target tracking systems.To improve the dynamic performance of the alpha–beta filter algorithm,a new prediction learning model is proposed in this study.The proposed model has two main components:(1)the alpha–beta filter algorithm is the main prediction module,and(2)the learning module is a feedforward artificial neural network(FF‐ANN).Furthermore,the model uses two inputs,temperature sensor and humidity sensor data,and a prediction algorithm is used to predict actual sensor readings from noisy sensor readings.Using the novel proposed technique,prediction accuracy is significantly improved while adding the feed‐forward backpropagation neural network,and also reduces the root mean square error(RMSE)and mean absolute error(MAE).We carried out different experiments with different experimental setups.The proposed model performance was evaluated with the traditional alpha–beta filter algorithm and other algorithms such as the Kalman filter.A higher prediction accuracy was achieved,and the MAE and RMSE were 35.1%–38.2%respectively.The final proposed model results show increased performance when compared to traditional methods.
文摘Cooling the PV surface in a Photovoltaic Thermal system is a pivotal operational aspect to be taken into account to achieve optimized values of performance parameters in a Photovoltaic Thermal System.The experimental design used in this study facilitates the flow of varying concentrations of Zn-water nanofluid in serpentine copper tubing installed at the rear of the PV panel thereby preventing the PV surface temperature from increasing beyond the threshold value at which a decrease in electrical efficiency starts to occur.This fusion of solar thermal with PV devices leads to better electrical and thermal efficiency values resulting in decreased cell degradation over time and maximization of the lifespan of the PV module and the energy output from the PV system.Due to the superior thermal heat properties of nanofluids,their usage in such systems has become increasingly widespread.Life cycle metrics which include Energy Payback period,Energy Production Factor and life cycle conversion efficiency were evaluated for the PVT system by exhaustively chalking fundamental parameters such as embodied energy of the PVT setup and the total energy output from the PVT system.This research aims to be a major milestone in the evolutionary journey of Photovoltaic Thermal modules by guiding the engineers working on the theory,design and implementation of PVT systems towards its economic feasibility,environmental impact and energy sustainability.
文摘Background: Several circumstances and conditions lead to UGIB. The commonest among them peptic ulcer to an approximation of 50% in cases. The second major cause may be esoghageal varices and third is mallory-weis tears. There are also other causes, which may include erosins, tumors and other malformations like arteriovenous. Methods: This was an observational retrospective study of all patients referred to endoscopy. The study exclusion criteria include all patients who had repeat endoscopies within one month of the previous endoscopy whereas all the patients with UGIB were included in this study. Results: We retrieved data of total 150 patients who had experienced upper gastrointestinal endoscopy during the selected time period covered in the study, March 2015 to February 2016. The mean age of the patients was 43.3 ± 13.80. 80 (53.3%) of the patients were male and 70 (46.7%) were females. Exploring more into UGIB causes the majority of patients were with esophageal varices 68 (45.3%) with male to female share was 2:1. The second most cause was esophagitis (n = 22, (14.67%)), the distribution of the cause was similar in male to female. Conclusion: We may conclude from our findings that the most common cause of UGIB is esophageal varices in our population.
基金supported by China Commerce Ministry (foreign-aid project (2007)420)China Geological Survey (Nos. DD20190443, DD20160109)。
文摘The voluminous Choke Shield basalts and flood basalts are distributed in the central Ethiopian Plateau.They are tholeiitic in composition and have OIB-like geochemical features.The ca.23 Ma Choke Shield basalts have SiO_(2)(47.1 wt.%-59.6 wt.%),MgO(1.01 wt.%-7.8 wt.%),Na_(2)O+K_(2)O(2.7 wt.%-8.4 wt.%),and display right inclined REE patterns((La/Yb)N=21.4-24.2) with enrichment of Nb,Ta,Zr,Hf and Pb in the primitive mantle-normalized trace element diagrams.They show low initial ^(87)Sr/^(86)Sr ratios(0.703 47-0.703 77) and high ε_(Nd)(t) values(+4.4 to+5.0).In comparison,the 24Ma high-Ti(HT1) flood basalts have SiO_(2)(38.9 wt.%-50.8 wt.%),MgO(3.9 wt.%-11.4 wt.%),Na_(2)O+K_(2)O(1.6 wt.%-5.8 wt.%), and display right inclined REE patterns((La/Yb)N=24-130.3) with enrichment of Nb,Ta,Zr,Hf,and Pb.They also show low initial ^(87)Sr/^(86)Sr ratios(0.703 30-0.704 44) and highε_(Nd)(t) values(+2.2 to+5.3).Both types of basalts were contaminated by minor crustal materials and underwent fractional crystallization of clinopyroxene,plagioclase,olivine,and minor Fe-Ti oxide.The Choke Shield basalts were generated by 1%-5% melting of garnet-spinel to phlogopite-bearing spinel lherzolite in a shallow zone of the mantle plume,while the flood basalts were formed by <20% melting of amphibole-bearing garnet to garnet-spinel lherzolite in a deeper zone of the same mantle plume.The mantle source beneath the central Ethiopian Plateau was significantly heterogeneous during the Tertiary.It was characterized by EMI and EMII end-members that were formed by the metasomatism of the different components.
基金This work was financially supported by following funds:Huxiang Youth Talent Support Program(Grant No.2020RC3066)Postdoctoral Innovation Talents Project(Grant No.2020RC2064)+1 种基金Hunan Provincial Natural Science Foundation of China(Grant No.2019JJ50320/2020JJ5610)The Project of Improving the Diagnosis and Treatment Capacity of Hepatobiliary,Pancreas and Intestine Disease in Hunan Province(Xiangwei[2019]Grant No.118).
文摘Mucinous cystic tumor of the gallbladder is an extremely rare benign tumor,with potential for malignant degeneration.Mucinous cystic tumors of the cystic duct are divided into mucinous cystadenoma and mucinous cystadenocarcinoma.Currently,cystadenoma is generally considered to be a precancerous lesion of cystadenocarcinoma.At present,there are few cases reported worldwide,and there are no relevant guidelines for diagnosis and treatment of this disease.This article presents the collected clinical data of a patient with mucinous cystic tumor of the gallbladder who was admitted to the First Affiliated Hospital of Hunan Normal University,with the characteristics of the disease summarized in combination with a focused literature review.
