A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed u...A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed using electrophoretic deposition.The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium(CNT_(R))in a resin.The associated local thermal stress changes can be simulated by capturing the G'band position distribution of CNT_(R) in the epoxy at different temperatures.It was found that the G'band shifted to lower positions with increasing temperature,reaching a maximum difference of 2.43 cm^(−1) at 100℃.The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment(20-100℃)were investig-ated in detail.This work is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology.展开更多
As a data protection legislation with the dual objectives of market regulation and government supervision,the EU General Data Protection Regulation(GDPR)is designed to promote the cultivation of a market for data ele⁃...As a data protection legislation with the dual objectives of market regulation and government supervision,the EU General Data Protection Regulation(GDPR)is designed to promote the cultivation of a market for data ele⁃ments and to regulate the data processing subjects'behaviour.The civil legal norms to participate in the data market regulation are introduced,and a right-protected mode with the obligation norms of data controllers as the core is started by GDPR.However,from the perspective of GDPR's global enforcement effectiveness,as an export-orientated global standard and protection framework,the power regulation model of the EU's single digital market is facing the in⁃novative incentives of data market expansion and the tension of human rights protection.A more modest and moderate data governance regulation model has been opened by a new round of the EU digital market regulation.The legal sce⁃narios transition and digital platforms regulation more fit the regulatory demand and development goals of global digital economy development.The EU's determination to enhance the global digital market share and competitiveness is dem⁃onstrated.For China,the impact and security risks of the new round should be evaluated carefully,drawing on the ex⁃perience of the technical standpoint and institutional framework and regulatory rules of the EU digital market regula⁃tion,providing the regulatory models and Chinese solutions to respond to the EU digital market regulation,and enhanc⁃ing Chinese institutional discourse and rule-making leadership in the global digital economy.展开更多
By inducing the typical inventory control problem - the bullwhip effect, this paper presents vendor managed inventory (VMI) control methods on the basis of traditional methods of inventory management methods, construc...By inducing the typical inventory control problem - the bullwhip effect, this paper presents vendor managed inventory (VMI) control methods on the basis of traditional methods of inventory management methods, constructs a VMI mathematics model, and analyzes the influence of VMI on inventory cost and channel profit. Finally, a special case is studied to verify that VMI is an effective supply chain strategy that can not only increase channel profit of supplier and customer but also improve full channel coordination, thereby reducing the bullwhip effect.展开更多
A two-level supply chain model involving one supplier and one retailer with linear demand is developed, and supply chain coordination mechanisms under asymmetric information (the retailer' s cost structure is asymme...A two-level supply chain model involving one supplier and one retailer with linear demand is developed, and supply chain coordination mechanisms under asymmetric information (the retailer' s cost structure is asymmetric information) are proposed by employing game theory in two scenarios: coordination mechanisms under asymmetric information in a regular scenario (without disruption); and coordination mechanisms under asymmetric information in an irregular scenario ( with retailer cost disruptions). It is optimal for the supply chain to maintain the original production plan and to guarantee a steadily running system if variations of retailer costs are sufficiently low and do not exceed an upper bound. This shows that the original production plan has certain robustness under disruptions. Decisions must be re-made if a retailer' s cost change is greater and exceeds an upper bound. Impacts of retailer cost disruptions on the order quantity, the retail price, the wholesale price and each party' s as well as the system' s expected profits are investigated through numerical analyses.展开更多
Strained-Si pMOSFETs on very thin relaxed virtua l SiGe substrates are presented.The 240nm relaxed virtual Si 0.8 Ge 0.2 layer on 100nm low-temperature Si(LT-Si) is grown on Si(100) substrates by molecular be...Strained-Si pMOSFETs on very thin relaxed virtua l SiGe substrates are presented.The 240nm relaxed virtual Si 0.8 Ge 0.2 layer on 100nm low-temperature Si(LT-Si) is grown on Si(100) substrates by molecular beam epitaxy.LT-Si buffer layer is used to release stress of the SiGe layer so as to make it relaxed.DCXRD,AFM,and TEM measurements indicate that the strain relaxed degree of SiGe layer is 85%,RMS roughness is 1.02nm,and threading dislocation density is at most 107cm -2 .At room temperature,a maximum hole mobility of strained-Si pMOSFET is 140cm2/(V·s).Device performance is comparable to that of devices achieved on several microns thick relaxed virtual SiGe substrates.展开更多
The concept of the e-marketplace is introduced.Considering a supply chain with a single manufacturer who sells a single item in an e-marketplace,an analytical model for the use of the e-marketplace in a supply chain i...The concept of the e-marketplace is introduced.Considering a supply chain with a single manufacturer who sells a single item in an e-marketplace,an analytical model for the use of the e-marketplace in a supply chain is provided.Assuming the market demand is stochastic and price-dependent,the conditions under which the manufacturer and the e-marketplace owner share the market in equilibrium is developed.The existence and uniqueness of the optimal selling price,quantity and transaction percentage are proved.An integrated supply chain is put forward,and then the efficiency of supply chain coordination is studied by comparing the integrated supply chain with the decentralized supply chain.To gain further insights on the theoretical models,extensive simulations are then carried out.展开更多
Lattice matched InP based InAlAs/InGaAs HEMTs with 120GHz cutoff frequency are reported.These devices demonstrate excellent DC characteristics:the extrinsic transconductance of 600mS/mm,the threshold voltage of -1 ...Lattice matched InP based InAlAs/InGaAs HEMTs with 120GHz cutoff frequency are reported.These devices demonstrate excellent DC characteristics:the extrinsic transconductance of 600mS/mm,the threshold voltage of -1 2V,and the maximum current density of 500mA/mm.展开更多
To determine the extrusion force of pipe fabricated by continuous casting and extrusion (CASTEX) using an expansion combination die, the metallic expansion combination die was divided into diversion zone, expansion zo...To determine the extrusion force of pipe fabricated by continuous casting and extrusion (CASTEX) using an expansion combination die, the metallic expansion combination die was divided into diversion zone, expansion zone, flow dividing zone, welding chamber, and sizing zone, and the corresponding stress formulae in various zones were established using the slab method. The deformation zones of CASTEX groove were divided into liquid and semisolid zone, solid primary gripping zone, and solid gripping zone, and the formulae of pipe extrusion forces were established. Experiments were carried out on the self-designed CASTEX machine to obtain the aluminum pipe and measure its extrusion force using the expansion combination die. The experimental results of radial extrusion force for aluminum pipe are in good agreement with the calculated ones.展开更多
The space charge effect (SCE) of static induction transistor (SIT) that occurs in high current region is systematically studied.The I V equations are deduced and well agree with experimental results.Two kinds of ...The space charge effect (SCE) of static induction transistor (SIT) that occurs in high current region is systematically studied.The I V equations are deduced and well agree with experimental results.Two kinds of barriers are presented in SIT,corresponding to channel voltage barrier control (CVBC) mechanism and space charge limited control (SCLC) mechanism respectively.With the increase of drain voltage,the gradual transferring of operational mechanism from CVBC to SCLC is demonstrated.It points out that CVBC mechanism and its contest relationship with space charge barrier makes the SIT distinctly differentiated from JFET and triode devices,etc.The contest relationship of the two potential barriers also results in three different working regions,which are distinctly marked and analyzed.Furthermore,the extreme importance of grid voltage on SCE is illustrated.展开更多
A radiation hardened N channel Si power device——VDMNOSFET (Vertical Double Diffused Metal Nitride Oxide Semiconductor Field Effect Transistor) is fabricated by using a double layer (Si 3N 4 SiO 2) gate dielec...A radiation hardened N channel Si power device——VDMNOSFET (Vertical Double Diffused Metal Nitride Oxide Semiconductor Field Effect Transistor) is fabricated by using a double layer (Si 3N 4 SiO 2) gate dielectric and a self aligned heavily doped shallow P + region.The effects of ionizing radiation and transient high dose rate radiation of the power VDMNOSFET are also presented.Good radiation hardening performance is obtained,compared with the conventional power VDMOSFET.For the specified 200V VDMNOSFET,the threshold voltage shifts is only -0 5V at a Gamma dose of 1Mrad(Si) with +10V gate bias;the transconductance is degraded by 10% at a Gamma dose of 1Mrad(Si);and no burnout failures occur at the transient high dose rate of 1×10 12 rad(Si)/s.It is demonstrated that the ionizing radiation tolerance and burnout susceptibilities of the power MOSFET are improved significantly by using a double layer (Si 3N 4 SiO 2) gate dielectric and a self aligned heavily doped shallow P + region.展开更多
The coordinating pricing strategies with asymmetric cost information under disruptions are investigated in a one-supplier-one-retailer supply chain system.While the retailer's cost structure is asymmetric informat...The coordinating pricing strategies with asymmetric cost information under disruptions are investigated in a one-supplier-one-retailer supply chain system.While the retailer's cost structure is asymmetric information,supply chain pricing contract models(a wholesale price contract and an all-unit quantity discount contract)under asymmetric information are proposed by employing the principal-agent principle in a regular scenario.When the retailer's cost distribution is fluctuated by disruptions,we obtain the optimal emergency strategies of the supply chain under asymmetric information by considering deviation costs and show how to effectively handle the cost uncertainty.Using numerical methods,impacts of cost disruptions on the optimal wholesale price,the retailer price,the order quantity and the expected profits of the retailer,the supplier,as well as the total system are analyzed.It is found that the all-unit quantity discount policy can obtain better performance than the wholesale pricing policy.展开更多
This paper studies that the bullwhip effect of order releases and the amplifications of safety stock arise within the supply chain even when the demand model is ARIMA(0, 1, 1) and the forecast method used is a simple ...This paper studies that the bullwhip effect of order releases and the amplifications of safety stock arise within the supply chain even when the demand model is ARIMA(0, 1, 1) and the forecast method used is a simple exponentially weighted moving average. It also examines a vendor managed inventory (VMI) program to determine how it can help alleviate such negative effects, and gives the theoretical proofs and numerical illustrations. The results show that the effects with VMI are better than the effect without VMI in demand forecasting and safety stock levels, etc.展开更多
To estimate percentiles of a response distribution, the transformed response rule of Wetherill and Robbins-Monro sequential design were proposed under Log-Logistic model. Based on responses data, a necessary and suffi...To estimate percentiles of a response distribution, the transformed response rule of Wetherill and Robbins-Monro sequential design were proposed under Log-Logistic model. Based on responses data, a necessary and sufficient condition for the existence of maximum likelihood estimators and then the calculating formula were presented. After a simulation study, the proposed approach was applied to 65# detonator. Numerical results showed that estimators of percentiles from the proposed approach are robust to the parametric models lacking information on the original response distribution.展开更多
As for the supply chain consisting of a manufacturer and multiple competing retailers, the disruption management decision is considered for the demand disruption that both the investment sensitivity coefficient and th...As for the supply chain consisting of a manufacturer and multiple competing retailers, the disruption management decision is considered for the demand disruption that both the investment sensitivity coefficient and the investment-elasticity are changed simultaneously. Meanwhile, the corresponding solutions are given for different cases of the disruption, and the characteristics of the solutions are analyzed. The production plan is proved to he robustness under certain conditions, and the production plan of the coordination strategy is investigated for the disruption with appropriate contractual arrangement, i. e. , a subside rate schedule. Mutual restraints exist between the changed investment sensitivity coefficient and the investment-elasticity when the coordination mecha- nism is used. And the more the number of the retailers in the system, the more the subside provided by the suppler on the coordinaton strategy.展开更多
Based on the surface-gate and buried-gate structures,a novel buried-gate structure called the planar type buried-gate (PTBG) structure for static induction devices (SIDs) is proposed.An approach to realize a buried-ga...Based on the surface-gate and buried-gate structures,a novel buried-gate structure called the planar type buried-gate (PTBG) structure for static induction devices (SIDs) is proposed.An approach to realize a buried-gate type static induction transistor by conventional planar process technology is presented.Using this structure,it is successfully avoided the second epitaxy with a high degree of difficulty and the complicated mesa process in conventional buried gate.The experimental results demonstrate that this structure is desirable for application in power SIDs.Its advantages are high breakdown voltage and blocking gain.展开更多
The reverse snapback phenomena (RSP) on I-V characteristics of static induction thyristors (SITH) are physically researched. The I-V curves of the power SITH exhibit reverse snapback phenomena, and even turn to th...The reverse snapback phenomena (RSP) on I-V characteristics of static induction thyristors (SITH) are physically researched. The I-V curves of the power SITH exhibit reverse snapback phenomena, and even turn to the conducting-state,when the anode voltage in the forward blocking-state is increased to a critical value. The RSP I-V characteristics of the power SITH are analyzed in terms of operating mechanism, double carrier injection effect, space charge effect, electron-hole plasma in the channel, and the variation in carrier lifetime. The reverse snapback mechanism is theoretically pro- posed and the mathematical expressions to calculate the voltage and current values at the snapback point are presented. The computing results are compared with the experiment values.展开更多
ZnO nanosheets with thickness of a few nanometers are prepared by vapor transport and condensation method, and their structure and optical properties are well characterized. Field effect transistor (FET) and ultravi...ZnO nanosheets with thickness of a few nanometers are prepared by vapor transport and condensation method, and their structure and optical properties are well characterized. Field effect transistor (FET) and ultraviolet (UV) sensors are fabricated based on the ZnO nanosheets. Due to the peculiar structure of nanosheet, the FET shows n-type enhanced mode behavior and high electrical performance, and its field-effect mobility and on/off cur- rent ratio can reach 256 cm2/(V.s) and ~10^8, respectively. Moreover, the response of UV sensors can also be remarkably improved to ~3 × 10^8. The results make the ZnO nanosheets be a good material for the applications in nanoelectronic and optoelectronic devices.展开更多
A novel Schottky body-contacted structure for partially depleted SOI nMOSFET's is presented.This structure can be realized by forming a shallow n +-p junction and two sidewall spacers in the source region,and the...A novel Schottky body-contacted structure for partially depleted SOI nMOSFET's is presented.This structure can be realized by forming a shallow n +-p junction and two sidewall spacers in the source region,and then growing a thick silicide film,which can punch through the shallow junction and make a Schottky contact to the p-type silicon.Simulation results show that the anomalous subthreshold slope and kink effects are suppressed successfully and the drain breakdown voltage is improved considerably.This method has the same device area and is completely compatible with the bulk MOSFET process.展开更多
A three-dimensional finite element approach based on ABAQUS code was developed to investigate the effect of welding sequence on welding residual stress distribution in a thin-walled 6061 aluminum alloy structure. To o...A three-dimensional finite element approach based on ABAQUS code was developed to investigate the effect of welding sequence on welding residual stress distribution in a thin-walled 6061 aluminum alloy structure. To obtain sound numerical results, the therrno-mechanical behaviour was simulated using a direct-coupled formulation. Nine different simulation sequences were carried out by single-pass TIG welding of an octagonal pipe-plate joint, and the distributions of longitudinal and transverse residual stresses both on the outer and inner surfaces of the pipe were analyzed. The results suggest that the final residual stresses in the weld and its vicinity are not affected by the initial residual stresses of the structure. Selecting a suitable welding sequence can reduce the final residual stress in an octagonal pipe-plate joint.展开更多
文摘A study of the interfacial behavior and internal thermal stress distribution in fiber-reinforced composites is essential to assess their performance and reliability.CNT/carbon fiber(CF)hybrid fibers were constructed using electrophoretic deposition.The interfacial properties of CF/epoxy and CNT/CF/epoxy composites were statistically investigated and compared using in-situ thermal Raman mapping by dispersing CNTs as a Raman sensing medium(CNT_(R))in a resin.The associated local thermal stress changes can be simulated by capturing the G'band position distribution of CNT_(R) in the epoxy at different temperatures.It was found that the G'band shifted to lower positions with increasing temperature,reaching a maximum difference of 2.43 cm^(−1) at 100℃.The interfacial bonding between CNT/CF and the matrix and the stress distribution and changes during heat treatment(20-100℃)were investig-ated in detail.This work is important for studying thermal stress in fiber-reinforced composites by in-situ thermal Raman mapping technology.
基金The special project of Anhui Philosophy and Social Science Planning Project(AHSKXZX2021D03)。
文摘As a data protection legislation with the dual objectives of market regulation and government supervision,the EU General Data Protection Regulation(GDPR)is designed to promote the cultivation of a market for data ele⁃ments and to regulate the data processing subjects'behaviour.The civil legal norms to participate in the data market regulation are introduced,and a right-protected mode with the obligation norms of data controllers as the core is started by GDPR.However,from the perspective of GDPR's global enforcement effectiveness,as an export-orientated global standard and protection framework,the power regulation model of the EU's single digital market is facing the in⁃novative incentives of data market expansion and the tension of human rights protection.A more modest and moderate data governance regulation model has been opened by a new round of the EU digital market regulation.The legal sce⁃narios transition and digital platforms regulation more fit the regulatory demand and development goals of global digital economy development.The EU's determination to enhance the global digital market share and competitiveness is dem⁃onstrated.For China,the impact and security risks of the new round should be evaluated carefully,drawing on the ex⁃perience of the technical standpoint and institutional framework and regulatory rules of the EU digital market regula⁃tion,providing the regulatory models and Chinese solutions to respond to the EU digital market regulation,and enhanc⁃ing Chinese institutional discourse and rule-making leadership in the global digital economy.
文摘By inducing the typical inventory control problem - the bullwhip effect, this paper presents vendor managed inventory (VMI) control methods on the basis of traditional methods of inventory management methods, constructs a VMI mathematics model, and analyzes the influence of VMI on inventory cost and channel profit. Finally, a special case is studied to verify that VMI is an effective supply chain strategy that can not only increase channel profit of supplier and customer but also improve full channel coordination, thereby reducing the bullwhip effect.
基金The National Natural Science Foundation of China(No70671021)Jiangsu Postdoctoral Foundation (No0601015C)
文摘A two-level supply chain model involving one supplier and one retailer with linear demand is developed, and supply chain coordination mechanisms under asymmetric information (the retailer' s cost structure is asymmetric information) are proposed by employing game theory in two scenarios: coordination mechanisms under asymmetric information in a regular scenario (without disruption); and coordination mechanisms under asymmetric information in an irregular scenario ( with retailer cost disruptions). It is optimal for the supply chain to maintain the original production plan and to guarantee a steadily running system if variations of retailer costs are sufficiently low and do not exceed an upper bound. This shows that the original production plan has certain robustness under disruptions. Decisions must be re-made if a retailer' s cost change is greater and exceeds an upper bound. Impacts of retailer cost disruptions on the order quantity, the retail price, the wholesale price and each party' s as well as the system' s expected profits are investigated through numerical analyses.
文摘Strained-Si pMOSFETs on very thin relaxed virtua l SiGe substrates are presented.The 240nm relaxed virtual Si 0.8 Ge 0.2 layer on 100nm low-temperature Si(LT-Si) is grown on Si(100) substrates by molecular beam epitaxy.LT-Si buffer layer is used to release stress of the SiGe layer so as to make it relaxed.DCXRD,AFM,and TEM measurements indicate that the strain relaxed degree of SiGe layer is 85%,RMS roughness is 1.02nm,and threading dislocation density is at most 107cm -2 .At room temperature,a maximum hole mobility of strained-Si pMOSFET is 140cm2/(V·s).Device performance is comparable to that of devices achieved on several microns thick relaxed virtual SiGe substrates.
基金The National Key Technology R&D Program of China during the11th Five-Year Plan Period(No.2006BAH02A06)the Program Project of Humanity and Social Science of Ministry of Education in China(No.06JA630012)
文摘The concept of the e-marketplace is introduced.Considering a supply chain with a single manufacturer who sells a single item in an e-marketplace,an analytical model for the use of the e-marketplace in a supply chain is provided.Assuming the market demand is stochastic and price-dependent,the conditions under which the manufacturer and the e-marketplace owner share the market in equilibrium is developed.The existence and uniqueness of the optimal selling price,quantity and transaction percentage are proved.An integrated supply chain is put forward,and then the efficiency of supply chain coordination is studied by comparing the integrated supply chain with the decentralized supply chain.To gain further insights on the theoretical models,extensive simulations are then carried out.
文摘Lattice matched InP based InAlAs/InGaAs HEMTs with 120GHz cutoff frequency are reported.These devices demonstrate excellent DC characteristics:the extrinsic transconductance of 600mS/mm,the threshold voltage of -1 2V,and the maximum current density of 500mA/mm.
基金Projects(51334006,50274020)supported by the National Natural Science Foundation of China
文摘To determine the extrusion force of pipe fabricated by continuous casting and extrusion (CASTEX) using an expansion combination die, the metallic expansion combination die was divided into diversion zone, expansion zone, flow dividing zone, welding chamber, and sizing zone, and the corresponding stress formulae in various zones were established using the slab method. The deformation zones of CASTEX groove were divided into liquid and semisolid zone, solid primary gripping zone, and solid gripping zone, and the formulae of pipe extrusion forces were established. Experiments were carried out on the self-designed CASTEX machine to obtain the aluminum pipe and measure its extrusion force using the expansion combination die. The experimental results of radial extrusion force for aluminum pipe are in good agreement with the calculated ones.
文摘The space charge effect (SCE) of static induction transistor (SIT) that occurs in high current region is systematically studied.The I V equations are deduced and well agree with experimental results.Two kinds of barriers are presented in SIT,corresponding to channel voltage barrier control (CVBC) mechanism and space charge limited control (SCLC) mechanism respectively.With the increase of drain voltage,the gradual transferring of operational mechanism from CVBC to SCLC is demonstrated.It points out that CVBC mechanism and its contest relationship with space charge barrier makes the SIT distinctly differentiated from JFET and triode devices,etc.The contest relationship of the two potential barriers also results in three different working regions,which are distinctly marked and analyzed.Furthermore,the extreme importance of grid voltage on SCE is illustrated.
文摘A radiation hardened N channel Si power device——VDMNOSFET (Vertical Double Diffused Metal Nitride Oxide Semiconductor Field Effect Transistor) is fabricated by using a double layer (Si 3N 4 SiO 2) gate dielectric and a self aligned heavily doped shallow P + region.The effects of ionizing radiation and transient high dose rate radiation of the power VDMNOSFET are also presented.Good radiation hardening performance is obtained,compared with the conventional power VDMOSFET.For the specified 200V VDMNOSFET,the threshold voltage shifts is only -0 5V at a Gamma dose of 1Mrad(Si) with +10V gate bias;the transconductance is degraded by 10% at a Gamma dose of 1Mrad(Si);and no burnout failures occur at the transient high dose rate of 1×10 12 rad(Si)/s.It is demonstrated that the ionizing radiation tolerance and burnout susceptibilities of the power MOSFET are improved significantly by using a double layer (Si 3N 4 SiO 2) gate dielectric and a self aligned heavily doped shallow P + region.
基金The National Key Technology R&D Program of China during the11th Five-Year Plan Period(No.2006BAH02A06)Jiangsu Postdoctoral Foundation(No.0601015C)
文摘The coordinating pricing strategies with asymmetric cost information under disruptions are investigated in a one-supplier-one-retailer supply chain system.While the retailer's cost structure is asymmetric information,supply chain pricing contract models(a wholesale price contract and an all-unit quantity discount contract)under asymmetric information are proposed by employing the principal-agent principle in a regular scenario.When the retailer's cost distribution is fluctuated by disruptions,we obtain the optimal emergency strategies of the supply chain under asymmetric information by considering deviation costs and show how to effectively handle the cost uncertainty.Using numerical methods,impacts of cost disruptions on the optimal wholesale price,the retailer price,the order quantity and the expected profits of the retailer,the supplier,as well as the total system are analyzed.It is found that the all-unit quantity discount policy can obtain better performance than the wholesale pricing policy.
文摘This paper studies that the bullwhip effect of order releases and the amplifications of safety stock arise within the supply chain even when the demand model is ARIMA(0, 1, 1) and the forecast method used is a simple exponentially weighted moving average. It also examines a vendor managed inventory (VMI) program to determine how it can help alleviate such negative effects, and gives the theoretical proofs and numerical illustrations. The results show that the effects with VMI are better than the effect without VMI in demand forecasting and safety stock levels, etc.
文摘To estimate percentiles of a response distribution, the transformed response rule of Wetherill and Robbins-Monro sequential design were proposed under Log-Logistic model. Based on responses data, a necessary and sufficient condition for the existence of maximum likelihood estimators and then the calculating formula were presented. After a simulation study, the proposed approach was applied to 65# detonator. Numerical results showed that estimators of percentiles from the proposed approach are robust to the parametric models lacking information on the original response distribution.
基金Supported by the Scientific Research Foundation for Young Faulty of Nanjing University of Aeronautics & Astronautics(S0670-082)~~
文摘As for the supply chain consisting of a manufacturer and multiple competing retailers, the disruption management decision is considered for the demand disruption that both the investment sensitivity coefficient and the investment-elasticity are changed simultaneously. Meanwhile, the corresponding solutions are given for different cases of the disruption, and the characteristics of the solutions are analyzed. The production plan is proved to he robustness under certain conditions, and the production plan of the coordination strategy is investigated for the disruption with appropriate contractual arrangement, i. e. , a subside rate schedule. Mutual restraints exist between the changed investment sensitivity coefficient and the investment-elasticity when the coordination mecha- nism is used. And the more the number of the retailers in the system, the more the subside provided by the suppler on the coordinaton strategy.
文摘Based on the surface-gate and buried-gate structures,a novel buried-gate structure called the planar type buried-gate (PTBG) structure for static induction devices (SIDs) is proposed.An approach to realize a buried-gate type static induction transistor by conventional planar process technology is presented.Using this structure,it is successfully avoided the second epitaxy with a high degree of difficulty and the complicated mesa process in conventional buried gate.The experimental results demonstrate that this structure is desirable for application in power SIDs.Its advantages are high breakdown voltage and blocking gain.
文摘The reverse snapback phenomena (RSP) on I-V characteristics of static induction thyristors (SITH) are physically researched. The I-V curves of the power SITH exhibit reverse snapback phenomena, and even turn to the conducting-state,when the anode voltage in the forward blocking-state is increased to a critical value. The RSP I-V characteristics of the power SITH are analyzed in terms of operating mechanism, double carrier injection effect, space charge effect, electron-hole plasma in the channel, and the variation in carrier lifetime. The reverse snapback mechanism is theoretically pro- posed and the mathematical expressions to calculate the voltage and current values at the snapback point are presented. The computing results are compared with the experiment values.
文摘ZnO nanosheets with thickness of a few nanometers are prepared by vapor transport and condensation method, and their structure and optical properties are well characterized. Field effect transistor (FET) and ultraviolet (UV) sensors are fabricated based on the ZnO nanosheets. Due to the peculiar structure of nanosheet, the FET shows n-type enhanced mode behavior and high electrical performance, and its field-effect mobility and on/off cur- rent ratio can reach 256 cm2/(V.s) and ~10^8, respectively. Moreover, the response of UV sensors can also be remarkably improved to ~3 × 10^8. The results make the ZnO nanosheets be a good material for the applications in nanoelectronic and optoelectronic devices.
文摘A novel Schottky body-contacted structure for partially depleted SOI nMOSFET's is presented.This structure can be realized by forming a shallow n +-p junction and two sidewall spacers in the source region,and then growing a thick silicide film,which can punch through the shallow junction and make a Schottky contact to the p-type silicon.Simulation results show that the anomalous subthreshold slope and kink effects are suppressed successfully and the drain breakdown voltage is improved considerably.This method has the same device area and is completely compatible with the bulk MOSFET process.
基金Project(61075005)supported by the Fund of State Key Laboratory of Advanced Design and Manufacture for Vehicle Body in Hunan University,ChinaProject(09JJ1007)supported by Preeminent Youth Fund of Hunan Province,ChinaProject(51075132)supported by the National Natural Science Foundation of China
文摘A three-dimensional finite element approach based on ABAQUS code was developed to investigate the effect of welding sequence on welding residual stress distribution in a thin-walled 6061 aluminum alloy structure. To obtain sound numerical results, the therrno-mechanical behaviour was simulated using a direct-coupled formulation. Nine different simulation sequences were carried out by single-pass TIG welding of an octagonal pipe-plate joint, and the distributions of longitudinal and transverse residual stresses both on the outer and inner surfaces of the pipe were analyzed. The results suggest that the final residual stresses in the weld and its vicinity are not affected by the initial residual stresses of the structure. Selecting a suitable welding sequence can reduce the final residual stress in an octagonal pipe-plate joint.