Suppliers' selection in supply chain management (SCM) has attracted considerable research interests in recent years. Recent literatures show that neural networks achieve better performance than traditional statisti...Suppliers' selection in supply chain management (SCM) has attracted considerable research interests in recent years. Recent literatures show that neural networks achieve better performance than traditional statistical methods. However, neural networks have inherent drawbacks, such as local optimization solution, lack generalization, and uncontrolled convergence. A relatively new machine learning technique, support vector machine (SVM), which overcomes the drawbacks of neural networks, is introduced to provide a model with better explanatory power to select ideal supplier partners. Meanwhile, in practice, the suppliers' samples are very insufficient. SVMs are adaptive to deal with small samples' training and testing. The prediction accuracies for BPNN and SVM methods are compared to choose the appreciating suppliers. The actual examples illustrate that SVM methods are superior to BPNN.展开更多
This paper presents a novel transformer magnetic biasing control method for high-power high-performance AC power supplies. Serious consequences due to magnetic biasing and several methods to overcome magnetic biasing ...This paper presents a novel transformer magnetic biasing control method for high-power high-performance AC power supplies. Serious consequences due to magnetic biasing and several methods to overcome magnetic biasing are first discussed. The causes of the transformer magnetic biasing are then analyzed in detail. The proposed method is based on a high-pass filter inserted in the forward path and the feedforward control. Without testing magnetic biasing of transformer, this method can eliminate magnetic biasing of transformer completely in real-time waveform feedback control systems though the zero error of the Hall effect sensors varies with time and temperature. The method has already been employed in a 90KVA AC power supply. It is shown that it offers improved performance over existing ones. In this method, no sensors are used such that the zero error of the Hall effect sensors has not any influence on the system. It is simple to design and implement. Furthermore, the method is suitable for various power applications.展开更多
Objective:To introduce the emergency management of nursing human resources and supplies of a large general hospital when facing the outbreak of coronavirus disease 2019(COVID-19).Method:The Nursing Department of the h...Objective:To introduce the emergency management of nursing human resources and supplies of a large general hospital when facing the outbreak of coronavirus disease 2019(COVID-19).Method:The Nursing Department of the hospital fully executed its functional authority to establish a three-level echelon of sustainable support,allocate human recourses dynamically,organize pre-service training,supervise the key working steps,formulate positive incentive methods,and deploy medical supplies scientifically.Result:By taking these strategies,the hospital effectively improved the coping capacity of the nursing team and played a positive role in the prevention and treatment of COVID-19.Conclusion:The emergency management of nursing human resources and material resources for COVID-19 of the hospital is successful.But several deficiencies were identified as well,which indicated that the hospital needs to establish an efficient emergency management system,and pay attention to the practice of nursing emergency plans to enhance coping capacities in public health emergencies.展开更多
Objective: To evaluate the clinical value of serum tumor supplied group of factor (TSGF) in diagnosis of epithelial ovarian cancer. Methods: The serum TSGF was tested in 69 patients with epithelial ovarian cancer, 28...Objective: To evaluate the clinical value of serum tumor supplied group of factor (TSGF) in diagnosis of epithelial ovarian cancer. Methods: The serum TSGF was tested in 69 patients with epithelial ovarian cancer, 28 patients with benign ovarian lesion and 61 healthy women. The serum levels of vascular endothelial growth factor (VEGF) and CA125 were determined in patients with epithelial ovarian cancer and in those with benign ovarian lesion. The correlations of TSGF with VEGF and CA125 were investigated. Results: The serum level of TSGF in patients with epithelial ovarian cancer was obviously higher than in patients with benign ovarian lesion and in healthy women (P<0.01). The serum level of TSGF in patients with epithelial cancer was associated with stage and grade. TSGF was highest in stage III, followed by stage IV, and was lowest in stage I-II. The TSGF level was lower in well-differentiated tumors and was higher in poorly differentiated tumor. There were no significant difference among diagnostic value of TSGF, VEGF, and CA125 in differentiation between epithelial ovarian cancer and benign ovarian lesion (P>0.05). The serum level of TSGF and VEGF and CA125 in patients with epithelial ovarian cancer showed positive correlation (P<0.01, P<0.05, respectively). Conclusion: There is no marked difference in diagnostic value among TSGF, VEGF and CA125. TSGF has a certain value in diagnosis of epithelial ovarian cancer, and is helpful to distinguish epithelial ovarian cancer from benign ovarian lesion.展开更多
The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topolo...The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topology of soft-switching inverter arc welding power supplies. However, the output power still remains a certain value when the duty-cycle of leading arm decreases to zero. The working-mode of soft-switching inverter and the waveforms of major parameters with the condition of duty-cycle of leading arm being zero are studied in this paper. U-1 characteristic experiments prove that the minimum output power of soft-switching circuit, which depends on the charged voltage of capacitors in parallel with leading arm, can be decreased by reducing the duty-cycle of lagging arm. By switching working-modes between half-bridge and full-bridge, the output power can swing from zero to the power rating.展开更多
Supplier selection is a vital part of the supply chain and is also a current issue that concerns businesses today as supplier quality directly affects the operations of the organization.Choosing the right supplier can...Supplier selection is a vital part of the supply chain and is also a current issue that concerns businesses today as supplier quality directly affects the operations of the organization.Choosing the right supplier can help businesses increase productivity,competitiveness in the market,and profits without having to lower the quality of the products.However,choosing a supplier is not a simple matter,it requires businesses to consider many aspects about their suppliers.Therefore,the goal of this study is to propose an integrated model consisting of two models:Fuzzy Analytics Network Process(Fuzzy-ANP)model and Weighted Aggregated Sum Product Assessment(WASPAS)to solve the problem above.The Fuzzy-ANP model was developed to evaluate the weightings of the supplier selection criteria,and the WASPAS Model was used to rank the suppliers.An example of supplier selection in the coffee industry in Vietnam was studied to validate the model,namely 5 main criteria,with 16 sub-criteria,and 7 suppliers.The model test results show that the Fuzzy ANP and WASPAS integration model was suitable.In future,these developing models can apply to other industries or integrate with other models.展开更多
Humans' immoderate exploit of natural resources causes a crisis to their own living environment. Besides the hazards from industry and agriculture production process, a large of garbage produced in people's da...Humans' immoderate exploit of natural resources causes a crisis to their own living environment. Besides the hazards from industry and agriculture production process, a large of garbage produced in people's daily work also destroy the ecological environment. Everyday office supplies consume considerably increasing resources. Green design indicates people's reflection on the worse environment and ecology inflicted by modern technological culture. Therefore, applying green design to office supplies, big resources consumers, has a profound and practical meaning in improving our living environment.展开更多
Presently,the environmental pollution problem,especially that of the small and medium-sized enterprises,has become a bottleneck restricting the high-quality development of China’s economy.It is imperative to accelera...Presently,the environmental pollution problem,especially that of the small and medium-sized enterprises,has become a bottleneck restricting the high-quality development of China’s economy.It is imperative to accelerate the construction of a collaborative governance system with multiple subject participation.The behavior modes of Environmental Non-governmental Organizations(ENGOs),a key player in environmental care,in collaborating with core enterprises to control pollution from small and medium-sized suppliers should be explored.Therefore,we constructed a collaborative governance system consisting of ENGOs,focal firms and small and medium-sized suppliers.Then a two-stage game model was established to analyze the strategies of the governance system.Specifically,we studied the collaborative green cooperation strategy and antagonistic pressure supervision strategy between ENGOs and focal firms,analyzed factors influencing the strategic choices of each subject,and gave the advantages of the cooperation strategies through further comparisons.The results showed that:Under the cooperation strategy,ENGOs provided knowledge of environmental protection to the focal firms,then both the audit efforts of focal firms and the environmental protection efforts of small and medium-sized suppliers were effectively improved.Since ENGOs could not fully obtain the pollution information of small and medium-sized suppliers or accurately trace it from their downstream focal firms,it was difficult to drive the supply chain’s endogenous governance by this external monitoring of ENGOs,making the effect of pressure supervision strategy limited.The effectiveness of green cooperation strategy was positively correlated with the knowledge absorption capacity of focal firms,the unit product revenue,and the focal firms'violation penalties for small and medium-sized suppliers.When ENGOs'violation penalties for small and medium-sized suppliers were higher,or the reputation loss of focal firms was higher,more unfavorable conditions of green cooperation strategy could be achieved.Accordingly,ENGOs should choose to cooperate with focal firms with strong knowledge absorption ability and high profit per product;focal firms should learn environmental protection knowledge to improve the screening standards and review capabilities,and promote the achievement of green cooperation strategy conditions by strengthening active information disclosure;the government should promote the collaboration between ENGOs and focal firms by issuing environmental guidelines.展开更多
Xinhua reported on March 20 that prices of major farm produce monitored by the government rose as snow falls interrupted supplies,the Ministry of Commerce said.The wholesale prices of 18 staple vegetables rose 3.2 per...Xinhua reported on March 20 that prices of major farm produce monitored by the government rose as snow falls interrupted supplies,the Ministry of Commerce said.The wholesale prices of 18 staple vegetables rose 3.2 percent from one week earlier,and the prices have increased 9.展开更多
<span style="font-family:Verdana;">Technologies for gas conversion have attracted more serious attention, but energy efficiency, supply deficiencies, as well as other risks undermining the gas supply i...<span style="font-family:Verdana;">Technologies for gas conversion have attracted more serious attention, but energy efficiency, supply deficiencies, as well as other risks undermining the gas supply industry</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> make it difficult to achieve sustainability in gas supply in Ghana. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">This study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">explored strategies for improving supplies for sustainable power generation in Ghana. Specifically, the study investigates the risks associated with the gas supply industry and also investigates strategies for improving gas supplies in Ghana. A descriptive study that applied both qualitative and quantitative tools was applied to data collection and analysis to allow for an in-depth analysis of the findings of the research. The population was concentrated on the regulators (Energy Commission) and consumers (VRA and Sunon Asogli, and GNGC/Eni in the supply domains. In all, 357 population w</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">as</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> targeted with a sample of 151. Probability (simple random sampling) and non-probability (purposive) sampling approaches were applied to source participants for the study. Statistical inferential tools that guided the analysis included means, standard deviation, Relative Importance Index (RII). The study identified issues of power sector debt due to the weak financial background of the gas supply sector, poor infrastructure, issues of corruption created by delays, poor transparency and weak regulatory framework as key risk factors in the gas supply industry in Ghana. The study also concluded that strategies to support the drive to achieve sustainability in the gas supply industry should involve a planned action towards providing regular and improved infrastructure in transportation and gas supply pipelines to enhance the visibility of the local gas industry and to also meet both domestic and industrial demand for gas products. Again, there should be the establishment and maintenance of functional gas-related policies and regulators, as well as an emergency supply plan to address any shocks that may tend to impact the gas supply industry in Ghana.</span></span></span>展开更多
A practical application for patrolling the device’s status and displalying beam status of HIRFL has been described.With regard to the kinds of the controlled devices,the system consists of two parts:First,the alarm s...A practical application for patrolling the device’s status and displalying beam status of HIRFL has been described.With regard to the kinds of the controlled devices,the system consists of two parts:First,the alarm system is applied to monitor all power supplies,which are decomposed into six groups in accordance with their positions for the convenience of user’s operation.The amount of magnet lens and power supplies of展开更多
The Guddu Thermal Power Plant of WAPDA is a main fossil powerplant in Pakistan,among which unit 4 with 210 MW in capacity suppliedby China,went into operation in 1986.Two 110 MW boiler-turbine-generator units and one ...The Guddu Thermal Power Plant of WAPDA is a main fossil powerplant in Pakistan,among which unit 4 with 210 MW in capacity suppliedby China,went into operation in 1986.Two 110 MW boiler-turbine-generator units and one 9 MW gas turbine-generator unit of phase Ⅰ projectof the power plant,provided by Skoda Export Co.of Czechoslovakia,wereput into operation in 1974,while one 210 MW boiler-turbine-generatorunit of phase Ⅱ,provided by the Technical Export Corporation of theSoviet Union,was put into operation in 1980.For the phase Ⅲ,one 210 MW boiler-turbine-generator unit,Which展开更多
In 2001, CSR power supply system made a great progress. Three prototypes were designed for CSR quadruple and correct magnet. Three different companies provided the three prototypes, but the same circuit-chopper were e...In 2001, CSR power supply system made a great progress. Three prototypes were designed for CSR quadruple and correct magnet. Three different companies provided the three prototypes, but the same circuit-chopper were employed. The simplified diagram is showed in Fig.1. All pulsed switching power supply prototypes were tested successfully before the end of 2001.展开更多
Dielectric barrier discharges(DBDs)have been widely used in ozone synthesis,materials surface treatment,and plasma medicine for their advantages of uniform discharge and high plasmachemical reactivity.To improve the r...Dielectric barrier discharges(DBDs)have been widely used in ozone synthesis,materials surface treatment,and plasma medicine for their advantages of uniform discharge and high plasmachemical reactivity.To improve the reactivity of DBDs,in this work,the O_(2) is added into Ar nanosecond(ns)pulsed and AC DBDs.The uniformity and discharge characteristics of Ar ns pulsed and AC DBDs with different O_(2) contents are investigated with optical and electrical diagnosis methods.The DBD uniformity is quantitatively analyzed by gray value standard deviation method.The electrical parameters are extracted from voltage and current waveforms separation to characterize the discharge processes and calculate electron density n_(e).The optical emission spectroscopy is measured to show the plasma reactivity and calculate the trend of electron temperature T_(e) with the ratio of two emission lines.It is found that the ns pulsed DBD has a much better uniformity than AC DBD for the fast rising and falling time.With the addition of O_(2),the uniformity of ns pulsed DBD gets worse for the space electric field distortion by O_(2)^(-),which promotes the filamentary formation.While,in AC DBD,the added O_(2) can reduce the intensity of filaments,which enhances the discharge uniformity.The ns pulsed DBD has a much higher instantaneous power and energy efficiency than AC DBD.The ratio of Ar emission intensities indicates that the T_(e) drops quickly with the addition of O_(2) both ns pulsed and AC DBDs and the ns pulsed DBD has an obvious higher T_(e) and n_(e) than AC DBD.The results are helpful for the realization of the reactive and uniform low temperature plasma sources.展开更多
Prior research has generally focused on models involving a single or multiple retailers with independent demands. The value of demand information sharing is analyzed in a two-level supply chain involving one supplier-...Prior research has generally focused on models involving a single or multiple retailers with independent demands. The value of demand information sharing is analyzed in a two-level supply chain involving one supplier-multiple retailer model in which retailer demands may be correlated. Each member in the supply chain forecasts its demand using an AR (1) demand process. Two conditions of the information sharing are considered (1) Without the information sharing, the retailers only communicate their orders to the supplier. (2) With the information sharing, retailers communicate their orders and forecasting models to the supplier. Analyses showthat the reductions of supplier's average inventory and average costs are substantial with the information sharing. However, the retailers donot get direct benefit from the information sharing. The retailers may ask the supplier to reduce the replenishment leadtime, so that the retailers will obtain substantial cost savings and inventory reduction. Both partners may obtain benefits when information sharing and leadtime reduction are implemented together.展开更多
This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local supplier.To reduce dependence on global suppli...This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local supplier.To reduce dependence on global suppliers and improve supply stability,we develop a differential game model to investigate the optimal investment decisions of the OEM towards the local supplier under different risk scenarios and the impact of different risks on the optimal decisions.The results show that investment efficiency and risks have a significant impact on OEM investment decisions.Specifically,when the OEM has higher investment efficiency,investing in the local supplier is profitable for the OEM;conversely,when the investment efficiency of the OEM is lower,it does not invest.In addition,an increase in the supply risk of the global supplier will lower the entry threshold for OEM investment,but an increase in the supply risk of the local supplier and the reputational risk of both will increase this threshold,meaning that only the OEM with significantly higher investment efficiency can profit.展开更多
The pulsed power supply(PPS)is one important component in the electromagnetic launch system.The inductive PPSs have attracted researchers’attentions with the major advantages of high energy storage density(over the c...The pulsed power supply(PPS)is one important component in the electromagnetic launch system.The inductive PPSs have attracted researchers’attentions with the major advantages of high energy storage density(over the capacitive PPSs)as well as simple structure and easy control(over the rotating mechanical PPSs).As for the inductive PPSs,the circuit topology of the basic module will directly determine the comprehensive performance of the whole system.From the perspectives of working principles,strengths,weaknesses,and comprehensive performance,this paper presents a historical and technical review of the major circuit topologies for the inductive PPSs.展开更多
Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effec...Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effective in DC-DC converters and DC-AC converters. Controller models are set up, and the over-current limit operation principles of analogy and digital control are analyzed too. An 800VA aeronautical power supply has been constructed to verify the performance of the proposed control strategy in various cases such as the sudden load change and the constant load. The analysis and experiments confirm the advantages of the proposed over-current limit strategies as follows: simple,effective and reliable.展开更多
文摘Suppliers' selection in supply chain management (SCM) has attracted considerable research interests in recent years. Recent literatures show that neural networks achieve better performance than traditional statistical methods. However, neural networks have inherent drawbacks, such as local optimization solution, lack generalization, and uncontrolled convergence. A relatively new machine learning technique, support vector machine (SVM), which overcomes the drawbacks of neural networks, is introduced to provide a model with better explanatory power to select ideal supplier partners. Meanwhile, in practice, the suppliers' samples are very insufficient. SVMs are adaptive to deal with small samples' training and testing. The prediction accuracies for BPNN and SVM methods are compared to choose the appreciating suppliers. The actual examples illustrate that SVM methods are superior to BPNN.
文摘This paper presents a novel transformer magnetic biasing control method for high-power high-performance AC power supplies. Serious consequences due to magnetic biasing and several methods to overcome magnetic biasing are first discussed. The causes of the transformer magnetic biasing are then analyzed in detail. The proposed method is based on a high-pass filter inserted in the forward path and the feedforward control. Without testing magnetic biasing of transformer, this method can eliminate magnetic biasing of transformer completely in real-time waveform feedback control systems though the zero error of the Hall effect sensors varies with time and temperature. The method has already been employed in a 90KVA AC power supply. It is shown that it offers improved performance over existing ones. In this method, no sensors are used such that the zero error of the Hall effect sensors has not any influence on the system. It is simple to design and implement. Furthermore, the method is suitable for various power applications.
文摘Objective:To introduce the emergency management of nursing human resources and supplies of a large general hospital when facing the outbreak of coronavirus disease 2019(COVID-19).Method:The Nursing Department of the hospital fully executed its functional authority to establish a three-level echelon of sustainable support,allocate human recourses dynamically,organize pre-service training,supervise the key working steps,formulate positive incentive methods,and deploy medical supplies scientifically.Result:By taking these strategies,the hospital effectively improved the coping capacity of the nursing team and played a positive role in the prevention and treatment of COVID-19.Conclusion:The emergency management of nursing human resources and material resources for COVID-19 of the hospital is successful.But several deficiencies were identified as well,which indicated that the hospital needs to establish an efficient emergency management system,and pay attention to the practice of nursing emergency plans to enhance coping capacities in public health emergencies.
文摘Objective: To evaluate the clinical value of serum tumor supplied group of factor (TSGF) in diagnosis of epithelial ovarian cancer. Methods: The serum TSGF was tested in 69 patients with epithelial ovarian cancer, 28 patients with benign ovarian lesion and 61 healthy women. The serum levels of vascular endothelial growth factor (VEGF) and CA125 were determined in patients with epithelial ovarian cancer and in those with benign ovarian lesion. The correlations of TSGF with VEGF and CA125 were investigated. Results: The serum level of TSGF in patients with epithelial ovarian cancer was obviously higher than in patients with benign ovarian lesion and in healthy women (P<0.01). The serum level of TSGF in patients with epithelial cancer was associated with stage and grade. TSGF was highest in stage III, followed by stage IV, and was lowest in stage I-II. The TSGF level was lower in well-differentiated tumors and was higher in poorly differentiated tumor. There were no significant difference among diagnostic value of TSGF, VEGF, and CA125 in differentiation between epithelial ovarian cancer and benign ovarian lesion (P>0.05). The serum level of TSGF and VEGF and CA125 in patients with epithelial ovarian cancer showed positive correlation (P<0.01, P<0.05, respectively). Conclusion: There is no marked difference in diagnostic value among TSGF, VEGF and CA125. TSGF has a certain value in diagnosis of epithelial ovarian cancer, and is helpful to distinguish epithelial ovarian cancer from benign ovarian lesion.
文摘The full-bridge zero-voltage and zero-current switching inverter, which can adjust the output power by keeping the duty-cycle of lagging arm constant, changing the duty-cycle of leading arm, is a common circuit topology of soft-switching inverter arc welding power supplies. However, the output power still remains a certain value when the duty-cycle of leading arm decreases to zero. The working-mode of soft-switching inverter and the waveforms of major parameters with the condition of duty-cycle of leading arm being zero are studied in this paper. U-1 characteristic experiments prove that the minimum output power of soft-switching circuit, which depends on the charged voltage of capacitors in parallel with leading arm, can be decreased by reducing the duty-cycle of lagging arm. By switching working-modes between half-bridge and full-bridge, the output power can swing from zero to the power rating.
基金supported by Van Lang University,Vietnam and National Kaohsiung University of Science and Technology,Taiwan.
文摘Supplier selection is a vital part of the supply chain and is also a current issue that concerns businesses today as supplier quality directly affects the operations of the organization.Choosing the right supplier can help businesses increase productivity,competitiveness in the market,and profits without having to lower the quality of the products.However,choosing a supplier is not a simple matter,it requires businesses to consider many aspects about their suppliers.Therefore,the goal of this study is to propose an integrated model consisting of two models:Fuzzy Analytics Network Process(Fuzzy-ANP)model and Weighted Aggregated Sum Product Assessment(WASPAS)to solve the problem above.The Fuzzy-ANP model was developed to evaluate the weightings of the supplier selection criteria,and the WASPAS Model was used to rank the suppliers.An example of supplier selection in the coffee industry in Vietnam was studied to validate the model,namely 5 main criteria,with 16 sub-criteria,and 7 suppliers.The model test results show that the Fuzzy ANP and WASPAS integration model was suitable.In future,these developing models can apply to other industries or integrate with other models.
文摘Humans' immoderate exploit of natural resources causes a crisis to their own living environment. Besides the hazards from industry and agriculture production process, a large of garbage produced in people's daily work also destroy the ecological environment. Everyday office supplies consume considerably increasing resources. Green design indicates people's reflection on the worse environment and ecology inflicted by modern technological culture. Therefore, applying green design to office supplies, big resources consumers, has a profound and practical meaning in improving our living environment.
文摘Presently,the environmental pollution problem,especially that of the small and medium-sized enterprises,has become a bottleneck restricting the high-quality development of China’s economy.It is imperative to accelerate the construction of a collaborative governance system with multiple subject participation.The behavior modes of Environmental Non-governmental Organizations(ENGOs),a key player in environmental care,in collaborating with core enterprises to control pollution from small and medium-sized suppliers should be explored.Therefore,we constructed a collaborative governance system consisting of ENGOs,focal firms and small and medium-sized suppliers.Then a two-stage game model was established to analyze the strategies of the governance system.Specifically,we studied the collaborative green cooperation strategy and antagonistic pressure supervision strategy between ENGOs and focal firms,analyzed factors influencing the strategic choices of each subject,and gave the advantages of the cooperation strategies through further comparisons.The results showed that:Under the cooperation strategy,ENGOs provided knowledge of environmental protection to the focal firms,then both the audit efforts of focal firms and the environmental protection efforts of small and medium-sized suppliers were effectively improved.Since ENGOs could not fully obtain the pollution information of small and medium-sized suppliers or accurately trace it from their downstream focal firms,it was difficult to drive the supply chain’s endogenous governance by this external monitoring of ENGOs,making the effect of pressure supervision strategy limited.The effectiveness of green cooperation strategy was positively correlated with the knowledge absorption capacity of focal firms,the unit product revenue,and the focal firms'violation penalties for small and medium-sized suppliers.When ENGOs'violation penalties for small and medium-sized suppliers were higher,or the reputation loss of focal firms was higher,more unfavorable conditions of green cooperation strategy could be achieved.Accordingly,ENGOs should choose to cooperate with focal firms with strong knowledge absorption ability and high profit per product;focal firms should learn environmental protection knowledge to improve the screening standards and review capabilities,and promote the achievement of green cooperation strategy conditions by strengthening active information disclosure;the government should promote the collaboration between ENGOs and focal firms by issuing environmental guidelines.
文摘Xinhua reported on March 20 that prices of major farm produce monitored by the government rose as snow falls interrupted supplies,the Ministry of Commerce said.The wholesale prices of 18 staple vegetables rose 3.2 percent from one week earlier,and the prices have increased 9.
文摘<span style="font-family:Verdana;">Technologies for gas conversion have attracted more serious attention, but energy efficiency, supply deficiencies, as well as other risks undermining the gas supply industry</span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">,</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> make it difficult to achieve sustainability in gas supply in Ghana. </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">This study </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">explored strategies for improving supplies for sustainable power generation in Ghana. Specifically, the study investigates the risks associated with the gas supply industry and also investigates strategies for improving gas supplies in Ghana. A descriptive study that applied both qualitative and quantitative tools was applied to data collection and analysis to allow for an in-depth analysis of the findings of the research. The population was concentrated on the regulators (Energy Commission) and consumers (VRA and Sunon Asogli, and GNGC/Eni in the supply domains. In all, 357 population w</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">as</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> targeted with a sample of 151. Probability (simple random sampling) and non-probability (purposive) sampling approaches were applied to source participants for the study. Statistical inferential tools that guided the analysis included means, standard deviation, Relative Importance Index (RII). The study identified issues of power sector debt due to the weak financial background of the gas supply sector, poor infrastructure, issues of corruption created by delays, poor transparency and weak regulatory framework as key risk factors in the gas supply industry in Ghana. The study also concluded that strategies to support the drive to achieve sustainability in the gas supply industry should involve a planned action towards providing regular and improved infrastructure in transportation and gas supply pipelines to enhance the visibility of the local gas industry and to also meet both domestic and industrial demand for gas products. Again, there should be the establishment and maintenance of functional gas-related policies and regulators, as well as an emergency supply plan to address any shocks that may tend to impact the gas supply industry in Ghana.</span></span></span>
文摘A practical application for patrolling the device’s status and displalying beam status of HIRFL has been described.With regard to the kinds of the controlled devices,the system consists of two parts:First,the alarm system is applied to monitor all power supplies,which are decomposed into six groups in accordance with their positions for the convenience of user’s operation.The amount of magnet lens and power supplies of
文摘The Guddu Thermal Power Plant of WAPDA is a main fossil powerplant in Pakistan,among which unit 4 with 210 MW in capacity suppliedby China,went into operation in 1986.Two 110 MW boiler-turbine-generator units and one 9 MW gas turbine-generator unit of phase Ⅰ projectof the power plant,provided by Skoda Export Co.of Czechoslovakia,wereput into operation in 1974,while one 210 MW boiler-turbine-generatorunit of phase Ⅱ,provided by the Technical Export Corporation of theSoviet Union,was put into operation in 1980.For the phase Ⅲ,one 210 MW boiler-turbine-generator unit,Which
基金Supported by WTZ project of BMBF,German Government.
文摘In 2001, CSR power supply system made a great progress. Three prototypes were designed for CSR quadruple and correct magnet. Three different companies provided the three prototypes, but the same circuit-chopper were employed. The simplified diagram is showed in Fig.1. All pulsed switching power supply prototypes were tested successfully before the end of 2001.
基金supported by National Natural Science Foundation of China(Nos.52037004 and 51777091)。
文摘Dielectric barrier discharges(DBDs)have been widely used in ozone synthesis,materials surface treatment,and plasma medicine for their advantages of uniform discharge and high plasmachemical reactivity.To improve the reactivity of DBDs,in this work,the O_(2) is added into Ar nanosecond(ns)pulsed and AC DBDs.The uniformity and discharge characteristics of Ar ns pulsed and AC DBDs with different O_(2) contents are investigated with optical and electrical diagnosis methods.The DBD uniformity is quantitatively analyzed by gray value standard deviation method.The electrical parameters are extracted from voltage and current waveforms separation to characterize the discharge processes and calculate electron density n_(e).The optical emission spectroscopy is measured to show the plasma reactivity and calculate the trend of electron temperature T_(e) with the ratio of two emission lines.It is found that the ns pulsed DBD has a much better uniformity than AC DBD for the fast rising and falling time.With the addition of O_(2),the uniformity of ns pulsed DBD gets worse for the space electric field distortion by O_(2)^(-),which promotes the filamentary formation.While,in AC DBD,the added O_(2) can reduce the intensity of filaments,which enhances the discharge uniformity.The ns pulsed DBD has a much higher instantaneous power and energy efficiency than AC DBD.The ratio of Ar emission intensities indicates that the T_(e) drops quickly with the addition of O_(2) both ns pulsed and AC DBDs and the ns pulsed DBD has an obvious higher T_(e) and n_(e) than AC DBD.The results are helpful for the realization of the reactive and uniform low temperature plasma sources.
文摘Prior research has generally focused on models involving a single or multiple retailers with independent demands. The value of demand information sharing is analyzed in a two-level supply chain involving one supplier-multiple retailer model in which retailer demands may be correlated. Each member in the supply chain forecasts its demand using an AR (1) demand process. Two conditions of the information sharing are considered (1) Without the information sharing, the retailers only communicate their orders to the supplier. (2) With the information sharing, retailers communicate their orders and forecasting models to the supplier. Analyses showthat the reductions of supplier's average inventory and average costs are substantial with the information sharing. However, the retailers donot get direct benefit from the information sharing. The retailers may ask the supplier to reduce the replenishment leadtime, so that the retailers will obtain substantial cost savings and inventory reduction. Both partners may obtain benefits when information sharing and leadtime reduction are implemented together.
基金supported in part by the National Natural Science Foundation of China(NSFC)under Grant No.72271208the China Postdoctoral Science Foundation under Grant No.2023M741907.
文摘This paper considers the supplier investment decision-making problem in a supply chain consisting of an original equipment manufacturer(OEM),a global supplier,and a local supplier.To reduce dependence on global suppliers and improve supply stability,we develop a differential game model to investigate the optimal investment decisions of the OEM towards the local supplier under different risk scenarios and the impact of different risks on the optimal decisions.The results show that investment efficiency and risks have a significant impact on OEM investment decisions.Specifically,when the OEM has higher investment efficiency,investing in the local supplier is profitable for the OEM;conversely,when the investment efficiency of the OEM is lower,it does not invest.In addition,an increase in the supply risk of the global supplier will lower the entry threshold for OEM investment,but an increase in the supply risk of the local supplier and the reputational risk of both will increase this threshold,meaning that only the OEM with significantly higher investment efficiency can profit.
基金This work was supported in part by the National Natural Science Foundation of China under Grant 50877039in part by the Tsinghua University Initiative Scientific Research Program under Grant No.20121087927(Corresponding author:Xinjie Yu).
文摘The pulsed power supply(PPS)is one important component in the electromagnetic launch system.The inductive PPSs have attracted researchers’attentions with the major advantages of high energy storage density(over the capacitive PPSs)as well as simple structure and easy control(over the rotating mechanical PPSs).As for the inductive PPSs,the circuit topology of the basic module will directly determine the comprehensive performance of the whole system.From the perspectives of working principles,strengths,weaknesses,and comprehensive performance,this paper presents a historical and technical review of the major circuit topologies for the inductive PPSs.
基金the National Natural Science Foundation of China (Grant No.50237030).
文摘Some Over-Current Limit Control strategies are analyzed and designed to meet the demands of high reliability and rapid dynamic response in the aeronautical power supply applications. The control schemes are both effective in DC-DC converters and DC-AC converters. Controller models are set up, and the over-current limit operation principles of analogy and digital control are analyzed too. An 800VA aeronautical power supply has been constructed to verify the performance of the proposed control strategy in various cases such as the sudden load change and the constant load. The analysis and experiments confirm the advantages of the proposed over-current limit strategies as follows: simple,effective and reliable.