In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D re...In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D reconstruction.The compound eye of L.lewisii was of the apposition type,with an average of 121.88±7.64 ommatidia in males and 119.00±4.71 ommatidia in females.Each ommatidium was composed of a biconvex cornea,an acone consisting of four cone cells,eight retinular cells along with the rhabdom,two primary pigment cells,and numerous secondary pigment cells.The open type of rhabdom in L.lewisii consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells(R1~R6)and two vertically attached central rhabdomeres contributed by R7 and R8 respectively.The orientation of microvilli suggested a weak sensitivity to polarized light perception.展开更多
In order to restrain the high pumping voltage of braking procedure which is harmful to the system of electric armored vehicle. Based on the analysis of pumping voltage of the braking procedure, the relation between pu...In order to restrain the high pumping voltage of braking procedure which is harmful to the system of electric armored vehicle. Based on the analysis of pumping voltage of the braking procedure, the relation between pumping voltage and PWM ratio is derived and a new digital control method to restrain the pumping voltage by changing PWM ratio is put forward. Because the capacitance is decreased effectively, the volume of controller is reduced and the performance to price ratio is improved. The results of computer simulation and experiment proved that this method is feasible and valid.展开更多
Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The...Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The correlations between traffic flows and totals of benzene and toluene were studied during the period of vehicular traffic restrictions from August 17 to August 20 and non-traffic restrictions on August 16 and August 21. The correlation coef- ficient was 0.8 between benzene and toluene. And the calculated daily mean value ratios of benzene to toluene were 0.43-0.50. During the period of vehicular restrictions, traffic flows were reduced about 11.8% and the levels of benzene and toluene were reduced by 11.4% and 12.8%, respectively. The vehicle emissions were recognized as the major sources for atmospheric benzene and toluene in Beijing.展开更多
AIM:To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells.METHODS:Cinnamon extract was used to treat murine macrophage cel...AIM:To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells.METHODS:Cinnamon extract was used to treat murine macrophage cell line(Raw 264.7),mouse primary antigen-presenting cells(APCs,MHCII+) and CD11c+dendritic cells to analyze the effects of cinnamon extract on APC function.The mechanisms of action of cinnamon extract on APCs were investigated by analyzing cytokine production,and expression of MHC antigens and co-stimulatory molecules by quantitative real-time PCR and flow cytometry.In addition,the effect of cinnamon extract on antigen presentation capacity and APC-dependent T-cell differentiation were analyzed by [H3]-thymidine incorporation and cytokine analysis,respectively.To confirm the anti-inflammatory effects of cinnamon extract in vivo,cinnamon or PBS was orally administered to mice for 20 d followed by induction of experimental colitis with 2,4,6 trinitrobenzenesulfonic acid.The protective effects of cinnamon extract against experimental colitis were measured by checking clinical symptoms,histological analysis and cytokine expression prof iles in inflamed tissue.RESULTS:Treatment with cinnamon extract inhibited maturation of MHCII+ APCs or CD11c+ dendritic cells(DCs) by suppressing expression of co-stimulatory molecules(B7.1,B7.2,ICOS-L),MHCII and cyclooxygenase(COX)-2.Cinnamon extract induced regulatory DCs(rDCs) that produce low levels of pro-inflammatory cytokines [interleukin(IL)-1β,IL-6,IL-12,interferon(IFN)-γ and tumor necrosis factor(TNF)-α] while expressing high levels of immunoregulatory cytokines(IL-10 and transforming growth factor-β).In addition,rDCs generated by cinnamon extract inhibited APC-dependent T-cell proliferation,and converted CD4+ T cells into IL-10high CD4+ T cells.Furthermore,oral administration of cinnamon extract inhibited development and progression of intestinal colitis by inhibiting expression of COX-2 and pro-inflammatory cytokines(IL-1β,IFN-γ and TNF-α),while enhancing IL-10 levels.CONCLUSION:Our study suggests the potential of cinnamon extract as an anti-inflammatory agent by targeting the generation of regulatory APCs and IL-10+ regulatory T cells.展开更多
During the initiation, promotion, and progression of multi-step carcinogenesis, changes in specific host immuno- logical factors have been observed. Although immunology of oral cancer has long been focused on antigens...During the initiation, promotion, and progression of multi-step carcinogenesis, changes in specific host immuno- logical factors have been observed. Although immunology of oral cancer has long been focused on antigens and lymphocytes, the fact remains that the antigen presenting cells, like the Langerhans cells （LCs） of the epithelium are initiators and modulators of the immune response. LCs as sentinels of immune response, have been investigated in several orai mucosal diseases, including cancer. Inadequate presentation of tumor antigens by host dendritic cells is one potential mechanism that allows tumor progression, tn this review, the role of LCs in OSCC is discussed. Elucidation of the role of APCs, in particular LCs, may help to better understand the mechanisms underlying anti-tumour immune responses and, improve the effectiveness of anti-cancer immunity in tumour-bearing hosts. This section focuses on the roles LCs in the immunity of cancer and how cancer bypasses the dendritic cell-mediated immune responses, are discussed. Subsequently, the effects of tumor microenviornment on LC＇s and their therapeutic implications are elaborated.展开更多
Accumulating evidence has suggested that epigenetic marks including DNA methylation,small RNA and histone modification may involve hybrid vigor in plants.However,knowledge about how epigenetic marks in hybrids regulat...Accumulating evidence has suggested that epigenetic marks including DNA methylation,small RNA and histone modification may involve hybrid vigor in plants.However,knowledge about how epigenetic marks in hybrids regulate gene expression is still limited.Based on genome-wide DNA methylation landscapes of Arabidopsis thaliana Ler and C24 ecotypes and their reciprocal F1 hybrids which were obtained in our previous work,we analyzed allele-specific DNA methylation and distinguished cis-and trans-regulated DNA methylation in hybrids.Our study indicated that both cis-and trans-regulated DNA methylation played roles in hybrids,when cis-regulation played a major role in CG methylation and trans-regulation played major roles in CHG and CHH methylation.In addition,we observed correlations between trans-regulated DNA methylation and siRNA densities.Enriched siRNA regions were significantly concurrent with highly trans-regulated DNA methylation regions.Our results illustrated DNA methylation regulation patterns integrated with siRNAs in Arabidopsis hybrids,and shed light on understanding the mechanism of epigenetic reprogramming for hybrid vigor.展开更多
An armored face conveyor(AFC) is a key piece of equipment for a fully mechanized long-wall mining system and is currently the only means for transporting bulk material in hard coal mines. To date, the AFC power train ...An armored face conveyor(AFC) is a key piece of equipment for a fully mechanized long-wall mining system and is currently the only means for transporting bulk material in hard coal mines. To date, the AFC power train design has mainly been based on heuristics obtained via experience, coupled with simple calculations, which cannot take the dynamic behaviors and coupling effects of the components into consideration. Therefore, model-based and simulation-driven design is preferred. In this paper, a new design and analysis methodology for an AFC power train is presented to achieve the optimal dynamic characteristics and transmission performance. A preliminary design procedure for a power train is first introduced. Then, a system-level hydro-mechatronic model of the power train is built to evaluate and optimize the preliminary scheme. Sub-models, including those for the motors, fluid couplers, gearboxes, and chain, are obtained according to their individual disciplines and assembled to form the system-level model. The chain sub-system is discretized into multiple finite elements. Governing equations are established for each element based on the Newton Euler approach and assembled according to the topological structure of the chain system. In order to make the new approach applicable for engineers, a design and analysis software is developed, with a graphical user interface that involves the whole design process. MATLAB/SIMULINK is used as the computational engine, and Visual C++ is adopted to develop the interactive software framework. Simulations for the SGZ1000/2000 type AFC are provided as an illustrative case study to validate the effectiveness and practicality of the model and software package.展开更多
OBJECTIVE: To observe the influence of Xinfengcapsule(XFC) on abarticular pathologic changes(APCs) and other indices of patients with rheumatoid arthritis(RA) and explore the mechanism of action of XFC in improving su...OBJECTIVE: To observe the influence of Xinfengcapsule(XFC) on abarticular pathologic changes(APCs) and other indices of patients with rheumatoid arthritis(RA) and explore the mechanism of action of XFC in improving such changes.METHODS: Three-hundred RA patients were divided randomly into a treatment group(n=150) and control group(n=150). A normal control(NC)group(n=90) was also created. Changes in cardiac function, pulmonary function, anemia indices and platelet parameters of RA patients were measured.Curative effects of the two groups were compared,and comparison carried out with the NC group.RESULTS: In 300 RA patients, late diastolic peak flow velocity(A peak) was much higher(P<0.01)and early diastolic peak flow velocity(E peak), E/A,and left ventricular fraction shortening much lower(P<0.01) than those in the NC group. Vital capacity(VC), forced vital capacity in one second, forced vital capacity(FVC), maximal voluntary ventilation(MVV), maximal expiratory flow in 50% of VC(FEF50) and FEF75 were lowered remarkably(P<0.05 or P<0.01). Platelet count(PLT), plateletcrit(PCT) and mean platelet volume(MPV) increased markedly(P<0.05 or P<0.01), and hemoglobin(Hb)level decreased significantly(P<0.05). After XFC treatment, the A peak and PLT and PCT were much lower(P<0.05), and E/A and the number of red blood cells as well as Hb level were much higher(P<0.05), as were FVC, MVV and FEF50(P<0.05 or P<0.01), in the treatment group than those in the NC group. Total score of pain and swelling in joints,uric-acid level and high-sensitivity C-reactive protein level were much lower, and superoxide dismutase level as well as the number of CD4 +CD25+ regulation T cells(Treg) and CD4+CD25+CD127- Treg were much higher(P<0.05 or P<0.01)in the treatment group than those in the NC group.CONCLUSION: RA patients with pathologic changes in joints also suffer from lower cardiac and pulmonary functions and from parameters of anemia and platelet factors. XFC can improve the symptoms of RA patients, ameliorate their cardiac and pulmonary functions and reduce the parameters of anemia and platelet factors. XFC lowers the immune inflammatory reaction to improve APCs in RA patients.展开更多
With life cycle assessment(LCA) methodology,a life cycle model of coal-based vehicle fuels(CBVFs) including coal-based dimethyl ether(CBDME) and coal-based diesel(CBD) is established.Their primary energy consumption(P...With life cycle assessment(LCA) methodology,a life cycle model of coal-based vehicle fuels(CBVFs) including coal-based dimethyl ether(CBDME) and coal-based diesel(CBD) is established.Their primary energy consumption(PEC) and global warming potential(GWP) from well to wheel including feedstock extraction,fuel production,fuel consumption in vehicle and energy transportation are calculated and compared.Results show that the life cycle PEC and GWP of CBD pathway are 1.17 and 1.34 times as CBDME pathway.Based on the above results,CBDME will become a choice with great potential to replace conventional petroleum-based diesel (CPBD) in China.展开更多
Human reliability analysis(HRA) is an expansion of man-machine engineering. It is also a new multidisciplinary based on behavioral science, cognitive science, information processing, system analysis and probability st...Human reliability analysis(HRA) is an expansion of man-machine engineering. It is also a new multidisciplinary based on behavioral science, cognitive science, information processing, system analysis and probability statistics in order to analyze, predict, reduce and prevent human errors. Firstly, the quantitative analysis model of HRA is proposed based on Markov process theory by using human error probability(HEP) and error correction cycle(ECC) as parameters. And human reliability evaluation criterion is built. Then, the HRA process considering error correction is proposed based on cognitive reliability and error analysis method(CREAM). Finally, according to the characteristics of armored vehicle system, common performance condition(CPC) in CREAM is improved.A reliability impact index is characterized by the overall contexts of tasks. Human reliability evaluation criterion of armored vehicle system is formulated. And the result of HRA is obtained based on the method presented in this paper. In addition, the relative weights are estimated by combining scale of 10/10—18/2 and analytical hierarchy process(AHP), and the triangular fuzzy number considering confidence factor and optimism index is adopted in order to reduce the subjectivity. The analysis results show that the method presented in this paper is reasonable and feasible. Meantime, the method can provide guidance for human reliability analysis of other weapon systems.展开更多
The hydrothermal experiments with ketones and formic acid showed that the hydrogen transfer reduction of ketones can be conducted using formic acid as a hydride donor in the presence of NaOH at 300 ℃. The yield of al...The hydrothermal experiments with ketones and formic acid showed that the hydrogen transfer reduction of ketones can be conducted using formic acid as a hydride donor in the presence of NaOH at 300 ℃. The yield of alcohols was considerably higher at a much lower ratio of hydrogen source to ketones than the traditional Meerwein-Ponndorf-Verley （MPV） reduction, reaching 60% for isopropanol from acetone and 70% for lactic acid from pyruvic acid. Water molecules may act as a catalyst in the hydrogen transfer reduction of ketones under hydrothermal conditions.展开更多
文摘In this study,the morphology and ultrastructure of the compound eye of L.lewisii were investigated using scanning electron microscopy(SEM),transmission electron microscopy(TEM),microcomputed tomography(μCT),and 3D reconstruction.The compound eye of L.lewisii was of the apposition type,with an average of 121.88±7.64 ommatidia in males and 119.00±4.71 ommatidia in females.Each ommatidium was composed of a biconvex cornea,an acone consisting of four cone cells,eight retinular cells along with the rhabdom,two primary pigment cells,and numerous secondary pigment cells.The open type of rhabdom in L.lewisii consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells(R1~R6)and two vertically attached central rhabdomeres contributed by R7 and R8 respectively.The orientation of microvilli suggested a weak sensitivity to polarized light perception.
文摘In order to restrain the high pumping voltage of braking procedure which is harmful to the system of electric armored vehicle. Based on the analysis of pumping voltage of the braking procedure, the relation between pumping voltage and PWM ratio is derived and a new digital control method to restrain the pumping voltage by changing PWM ratio is put forward. Because the capacitance is decreased effectively, the volume of controller is reduced and the performance to price ratio is improved. The results of computer simulation and experiment proved that this method is feasible and valid.
文摘Measurements of atmospheric benzene and toluene were carried out continuously using dif- ferential optical absorption spectroscopy from August 7 to August 28 in Beijing during the period of vehicular restrictions. The correlations between traffic flows and totals of benzene and toluene were studied during the period of vehicular traffic restrictions from August 17 to August 20 and non-traffic restrictions on August 16 and August 21. The correlation coef- ficient was 0.8 between benzene and toluene. And the calculated daily mean value ratios of benzene to toluene were 0.43-0.50. During the period of vehicular restrictions, traffic flows were reduced about 11.8% and the levels of benzene and toluene were reduced by 11.4% and 12.8%, respectively. The vehicle emissions were recognized as the major sources for atmospheric benzene and toluene in Beijing.
基金Supported by Grants from the BioGreen 21 Program, Rural Development Administration (PJ007054)Regional Technology Innovation Program of the MOCIE (RTI05-01-01)Korea Healthcare Technology R&D Project, Ministry of Health and Welfare (A080588-20)
文摘AIM:To investigate the anti-inflammatory effects of cinnamon extract and elucidate its mechanisms for targeting the function of antigen presenting cells.METHODS:Cinnamon extract was used to treat murine macrophage cell line(Raw 264.7),mouse primary antigen-presenting cells(APCs,MHCII+) and CD11c+dendritic cells to analyze the effects of cinnamon extract on APC function.The mechanisms of action of cinnamon extract on APCs were investigated by analyzing cytokine production,and expression of MHC antigens and co-stimulatory molecules by quantitative real-time PCR and flow cytometry.In addition,the effect of cinnamon extract on antigen presentation capacity and APC-dependent T-cell differentiation were analyzed by [H3]-thymidine incorporation and cytokine analysis,respectively.To confirm the anti-inflammatory effects of cinnamon extract in vivo,cinnamon or PBS was orally administered to mice for 20 d followed by induction of experimental colitis with 2,4,6 trinitrobenzenesulfonic acid.The protective effects of cinnamon extract against experimental colitis were measured by checking clinical symptoms,histological analysis and cytokine expression prof iles in inflamed tissue.RESULTS:Treatment with cinnamon extract inhibited maturation of MHCII+ APCs or CD11c+ dendritic cells(DCs) by suppressing expression of co-stimulatory molecules(B7.1,B7.2,ICOS-L),MHCII and cyclooxygenase(COX)-2.Cinnamon extract induced regulatory DCs(rDCs) that produce low levels of pro-inflammatory cytokines [interleukin(IL)-1β,IL-6,IL-12,interferon(IFN)-γ and tumor necrosis factor(TNF)-α] while expressing high levels of immunoregulatory cytokines(IL-10 and transforming growth factor-β).In addition,rDCs generated by cinnamon extract inhibited APC-dependent T-cell proliferation,and converted CD4+ T cells into IL-10high CD4+ T cells.Furthermore,oral administration of cinnamon extract inhibited development and progression of intestinal colitis by inhibiting expression of COX-2 and pro-inflammatory cytokines(IL-1β,IFN-γ and TNF-α),while enhancing IL-10 levels.CONCLUSION:Our study suggests the potential of cinnamon extract as an anti-inflammatory agent by targeting the generation of regulatory APCs and IL-10+ regulatory T cells.
文摘During the initiation, promotion, and progression of multi-step carcinogenesis, changes in specific host immuno- logical factors have been observed. Although immunology of oral cancer has long been focused on antigens and lymphocytes, the fact remains that the antigen presenting cells, like the Langerhans cells （LCs） of the epithelium are initiators and modulators of the immune response. LCs as sentinels of immune response, have been investigated in several orai mucosal diseases, including cancer. Inadequate presentation of tumor antigens by host dendritic cells is one potential mechanism that allows tumor progression, tn this review, the role of LCs in OSCC is discussed. Elucidation of the role of APCs, in particular LCs, may help to better understand the mechanisms underlying anti-tumour immune responses and, improve the effectiveness of anti-cancer immunity in tumour-bearing hosts. This section focuses on the roles LCs in the immunity of cancer and how cancer bypasses the dendritic cell-mediated immune responses, are discussed. Subsequently, the effects of tumor microenviornment on LC＇s and their therapeutic implications are elaborated.
基金supported by Ministry of Science and Technology of China(2013CBA01402)Ministry of Science and Technology of China(2012CB910900)+1 种基金Ministry of Agriculture of China(2010ZX08010-003)Peking University 985 Program
文摘Accumulating evidence has suggested that epigenetic marks including DNA methylation,small RNA and histone modification may involve hybrid vigor in plants.However,knowledge about how epigenetic marks in hybrids regulate gene expression is still limited.Based on genome-wide DNA methylation landscapes of Arabidopsis thaliana Ler and C24 ecotypes and their reciprocal F1 hybrids which were obtained in our previous work,we analyzed allele-specific DNA methylation and distinguished cis-and trans-regulated DNA methylation in hybrids.Our study indicated that both cis-and trans-regulated DNA methylation played roles in hybrids,when cis-regulation played a major role in CG methylation and trans-regulation played major roles in CHG and CHH methylation.In addition,we observed correlations between trans-regulated DNA methylation and siRNA densities.Enriched siRNA regions were significantly concurrent with highly trans-regulated DNA methylation regions.Our results illustrated DNA methylation regulation patterns integrated with siRNAs in Arabidopsis hybrids,and shed light on understanding the mechanism of epigenetic reprogramming for hybrid vigor.
基金supported by the National Natural Science Foundation of China(Grant No.51375330)the Leading Talent Project of Guangdong Province
文摘An armored face conveyor(AFC) is a key piece of equipment for a fully mechanized long-wall mining system and is currently the only means for transporting bulk material in hard coal mines. To date, the AFC power train design has mainly been based on heuristics obtained via experience, coupled with simple calculations, which cannot take the dynamic behaviors and coupling effects of the components into consideration. Therefore, model-based and simulation-driven design is preferred. In this paper, a new design and analysis methodology for an AFC power train is presented to achieve the optimal dynamic characteristics and transmission performance. A preliminary design procedure for a power train is first introduced. Then, a system-level hydro-mechatronic model of the power train is built to evaluate and optimize the preliminary scheme. Sub-models, including those for the motors, fluid couplers, gearboxes, and chain, are obtained according to their individual disciplines and assembled to form the system-level model. The chain sub-system is discretized into multiple finite elements. Governing equations are established for each element based on the Newton Euler approach and assembled according to the topological structure of the chain system. In order to make the new approach applicable for engineers, a design and analysis software is developed, with a graphical user interface that involves the whole design process. MATLAB/SIMULINK is used as the computational engine, and Visual C++ is adopted to develop the interactive software framework. Simulations for the SGZ1000/2000 type AFC are provided as an illustrative case study to validate the effectiveness and practicality of the model and software package.
基金Supported by the Twelfth Five-Year Support Project of the Ministry of Science and Technology for Clinical Studies Investigating Xin'an Medicine in the Treatment of Complicated Ascites Diseases(No.2012BAI26B02)State Key Discipline Construction Project of TCM:Arthralgia[No.(2009)30]Technology Planning Project of Anhui Science and Technology Department(No.11010402170)
文摘OBJECTIVE: To observe the influence of Xinfengcapsule(XFC) on abarticular pathologic changes(APCs) and other indices of patients with rheumatoid arthritis(RA) and explore the mechanism of action of XFC in improving such changes.METHODS: Three-hundred RA patients were divided randomly into a treatment group(n=150) and control group(n=150). A normal control(NC)group(n=90) was also created. Changes in cardiac function, pulmonary function, anemia indices and platelet parameters of RA patients were measured.Curative effects of the two groups were compared,and comparison carried out with the NC group.RESULTS: In 300 RA patients, late diastolic peak flow velocity(A peak) was much higher(P<0.01)and early diastolic peak flow velocity(E peak), E/A,and left ventricular fraction shortening much lower(P<0.01) than those in the NC group. Vital capacity(VC), forced vital capacity in one second, forced vital capacity(FVC), maximal voluntary ventilation(MVV), maximal expiratory flow in 50% of VC(FEF50) and FEF75 were lowered remarkably(P<0.05 or P<0.01). Platelet count(PLT), plateletcrit(PCT) and mean platelet volume(MPV) increased markedly(P<0.05 or P<0.01), and hemoglobin(Hb)level decreased significantly(P<0.05). After XFC treatment, the A peak and PLT and PCT were much lower(P<0.05), and E/A and the number of red blood cells as well as Hb level were much higher(P<0.05), as were FVC, MVV and FEF50(P<0.05 or P<0.01), in the treatment group than those in the NC group. Total score of pain and swelling in joints,uric-acid level and high-sensitivity C-reactive protein level were much lower, and superoxide dismutase level as well as the number of CD4 +CD25+ regulation T cells(Treg) and CD4+CD25+CD127- Treg were much higher(P<0.05 or P<0.01)in the treatment group than those in the NC group.CONCLUSION: RA patients with pathologic changes in joints also suffer from lower cardiac and pulmonary functions and from parameters of anemia and platelet factors. XFC can improve the symptoms of RA patients, ameliorate their cardiac and pulmonary functions and reduce the parameters of anemia and platelet factors. XFC lowers the immune inflammatory reaction to improve APCs in RA patients.
文摘With life cycle assessment(LCA) methodology,a life cycle model of coal-based vehicle fuels(CBVFs) including coal-based dimethyl ether(CBDME) and coal-based diesel(CBD) is established.Their primary energy consumption(PEC) and global warming potential(GWP) from well to wheel including feedstock extraction,fuel production,fuel consumption in vehicle and energy transportation are calculated and compared.Results show that the life cycle PEC and GWP of CBD pathway are 1.17 and 1.34 times as CBDME pathway.Based on the above results,CBDME will become a choice with great potential to replace conventional petroleum-based diesel (CPBD) in China.
基金the Technical Basis Projects of China’s Ministry of Industry and Information Technology(No.ZQ092012B003)
文摘Human reliability analysis(HRA) is an expansion of man-machine engineering. It is also a new multidisciplinary based on behavioral science, cognitive science, information processing, system analysis and probability statistics in order to analyze, predict, reduce and prevent human errors. Firstly, the quantitative analysis model of HRA is proposed based on Markov process theory by using human error probability(HEP) and error correction cycle(ECC) as parameters. And human reliability evaluation criterion is built. Then, the HRA process considering error correction is proposed based on cognitive reliability and error analysis method(CREAM). Finally, according to the characteristics of armored vehicle system, common performance condition(CPC) in CREAM is improved.A reliability impact index is characterized by the overall contexts of tasks. Human reliability evaluation criterion of armored vehicle system is formulated. And the result of HRA is obtained based on the method presented in this paper. In addition, the relative weights are estimated by combining scale of 10/10—18/2 and analytical hierarchy process(AHP), and the triangular fuzzy number considering confidence factor and optimism index is adopted in order to reduce the subjectivity. The analysis results show that the method presented in this paper is reasonable and feasible. Meantime, the method can provide guidance for human reliability analysis of other weapon systems.
基金supported by the State Key Laboratory of Pollution Control and Resources Reuse in China (Tongji University) (No. PCRRK08002)the National Key Technology R&D Program of China (No. 2008BAJ08B13)the Shanghai Pujiang Elitist Program of China (No. 07pj14083)
文摘The hydrothermal experiments with ketones and formic acid showed that the hydrogen transfer reduction of ketones can be conducted using formic acid as a hydride donor in the presence of NaOH at 300 ℃. The yield of alcohols was considerably higher at a much lower ratio of hydrogen source to ketones than the traditional Meerwein-Ponndorf-Verley （MPV） reduction, reaching 60% for isopropanol from acetone and 70% for lactic acid from pyruvic acid. Water molecules may act as a catalyst in the hydrogen transfer reduction of ketones under hydrothermal conditions.
