The most prospective method for certain structural failures and damages that cannot employ redundancy is self-repairing techniques, to ensure especially the maximum flight safety. Based on the characters of self-repai...The most prospective method for certain structural failures and damages that cannot employ redundancy is self-repairing techniques, to ensure especially the maximum flight safety. Based on the characters of self-repairing aircraft, this paper states some basic assumptions of the self-repairing aircraft, and puts forward some special new conceptions concerning the self-repairing aircraft: control input, operating input, command input, repair input and operating and control factor as well as their relationships. Thus it provides a simple and reliable mathematical model structure for the research on the self-repairing control of the aircraft.展开更多
Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, ...Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, industry, military, entertainment and medicine. Combined with the characteristics of railway maintenance training, this thesis proposes the application of virtual reality in courseware, distance education, locomotive simulation driving, locomotive overhauling oil and breakdown processing, and illustrates key technology and solution of the exploitation of virtual reality technology.展开更多
With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficienc...With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficiency and accuracy for the specific case of military vehicular communication systems. Face to this situation, a modified four-level assessment model is proposed in the paper. First, the development of EMC assessment technology is briefly reviewed, and the theoretical mechanism of EMI environment is introduced. Then, the architecture of the proposed model is outlined, and the assessment methods are explored. To demonstrate the application of it, an example involving a communication system in a military vehicle is presented. From the physical layer to the signal layer, a hierarchical assessment on the entire system is successfully performed based on the proposed model, and we can make a qualitative EMC assessment on the EMC performance of the system. Based on a comparison with the traditional model, we conclude that the proposed model is more accurate, more efficient and less time-consuming, which is suitable for the EMC assessment on militaryvehicular communication systems. We hope that the proposed model will serve as a useful reference for system-level EMC assessments for other systems.展开更多
Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants ...Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes(such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However,the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.展开更多
There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural reme...There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural remediation(ANR) of an acid soil contaminated by As,Cd,Cu,Zn and Pb using one inorganic amendment,sugar beet lime(SL),and two organic amendments,biosolid compost(BC)and leonardeite(LE).The experiment was arranged in a completely randomized block design with four treatments in three replicates:1) a non-amended control(NA);2) SL amended at 30 Mg ha^(-1) year^(-1);3) BC amended at 30 Mg ha^(-1) year^(-1) and 4) LE amended at 20 Mg ha^(-1) year^(-1) plus SL amended at 10 Mg ha^(-1) year^(-1)(LESL).The amended plots received two doses of each amendment(DO2):one in October 2002 and another in October 2003.The plots were then divided in half into two subpolts and one subplot received another two doses of the same amendments(DO4) in October 2005 and October 2006.In 2011,the pH values of the amended soils were greater than that of the NA soil,with the SL-amended soil showing the highest pH.Total organic carbon(TOC) was also greater in the amended soil,and greater with DO4 than with DO2.Amendments reduced the concentrations of 0.01 mol L^(-1) CaCl_2-extractable Cd,Cu and Zn,especially in the SL-amended soil.Plant cover of colonizing vegetation was enhanced by amendments,but was independent of amendment doses.Changes in soil properties from 2003 to 2011 showed that the first amendment application of DO2 caused a high differentiation between all the amendment treatments and the NA treatment.After the second application of DO2,soil pH and TOC continued increasing slowly.Further two applications of amendments(DO4) caused differences only in the organic treatments.Plant cover increased over time in all the treatments including NA.It could be concluded that the slow and steady natural remediation of this soil could be enhanced by amendment application(ANR).展开更多
文摘The most prospective method for certain structural failures and damages that cannot employ redundancy is self-repairing techniques, to ensure especially the maximum flight safety. Based on the characters of self-repairing aircraft, this paper states some basic assumptions of the self-repairing aircraft, and puts forward some special new conceptions concerning the self-repairing aircraft: control input, operating input, command input, repair input and operating and control factor as well as their relationships. Thus it provides a simple and reliable mathematical model structure for the research on the self-repairing control of the aircraft.
文摘Virtual reality technology is a brand new comprehensive information technology emerging during the end of 21 st century. In recent years in particular, it gains rapid development, involving industries like education, industry, military, entertainment and medicine. Combined with the characteristics of railway maintenance training, this thesis proposes the application of virtual reality in courseware, distance education, locomotive simulation driving, locomotive overhauling oil and breakdown processing, and illustrates key technology and solution of the exploitation of virtual reality technology.
基金supported by the National Moon Exploration Program of China (No. TY3Q20110020)in part supported by the 13th Five-Year Community Technology Research Program of National Equipment Development Department of China (No.41409020301)the National Natural Science Foundation of China (50971094)
文摘With the development of EMC technology, EMC assessment has become increasingly important in EMC design. Although numerous EMC assessment models are available today, few of them can provide a tradeoff between efficiency and accuracy for the specific case of military vehicular communication systems. Face to this situation, a modified four-level assessment model is proposed in the paper. First, the development of EMC assessment technology is briefly reviewed, and the theoretical mechanism of EMI environment is introduced. Then, the architecture of the proposed model is outlined, and the assessment methods are explored. To demonstrate the application of it, an example involving a communication system in a military vehicle is presented. From the physical layer to the signal layer, a hierarchical assessment on the entire system is successfully performed based on the proposed model, and we can make a qualitative EMC assessment on the EMC performance of the system. Based on a comparison with the traditional model, we conclude that the proposed model is more accurate, more efficient and less time-consuming, which is suitable for the EMC assessment on militaryvehicular communication systems. We hope that the proposed model will serve as a useful reference for system-level EMC assessments for other systems.
基金financially supported by the Polish Ministry of Science and Higher Education(No.DS 3500)
文摘Environmental pollution caused by metals, radionuclides and organic pollutants affects quality of the biosphere: soil, water and air.Currently, great efforts have been made to reduce, remove or stabilize contaminants in polluted sites. There has been increasing interest in phytoremediation—the use of plants to reduce concentration of pollutants or to render them harmless. This paper provides a brief review of recent progress in the research and practical application of phytoremediation techniques. Improvements in phytoremediation due to utilization of organic amendments, namely, agro- and industrial wastes(such as sugar beet residue, composted sewage sludge or molasses), biochar, humic substances, plant extracts and exudates are discussed, as well as their influences on soil structure and characteristics, plants growth and bioavailability of pollutants. Both plant-assisted phytoremediation and the use of natural materials in the absence of remediating plant are believed to be cost-effective and environmentally friendly approaches for soil cleanup. However,the characterization and quantification of a range of natural materials used in phytoremediation are essential in order to implement these approaches to practice.
基金supported by the Programa Operativo Feder de Andalucia 2007-2013 of Sapin (No.PAIDI AGR108)the Project of the Plan Nacional de Investigacion of Spain(No.AGL201123617)
文摘There are many remediation techniques for organic contaminated soils,but relatively few of them are applicable to trace elementcontaminated soils.A field experiment was carried out to investigate assisted natural remediation(ANR) of an acid soil contaminated by As,Cd,Cu,Zn and Pb using one inorganic amendment,sugar beet lime(SL),and two organic amendments,biosolid compost(BC)and leonardeite(LE).The experiment was arranged in a completely randomized block design with four treatments in three replicates:1) a non-amended control(NA);2) SL amended at 30 Mg ha^(-1) year^(-1);3) BC amended at 30 Mg ha^(-1) year^(-1) and 4) LE amended at 20 Mg ha^(-1) year^(-1) plus SL amended at 10 Mg ha^(-1) year^(-1)(LESL).The amended plots received two doses of each amendment(DO2):one in October 2002 and another in October 2003.The plots were then divided in half into two subpolts and one subplot received another two doses of the same amendments(DO4) in October 2005 and October 2006.In 2011,the pH values of the amended soils were greater than that of the NA soil,with the SL-amended soil showing the highest pH.Total organic carbon(TOC) was also greater in the amended soil,and greater with DO4 than with DO2.Amendments reduced the concentrations of 0.01 mol L^(-1) CaCl_2-extractable Cd,Cu and Zn,especially in the SL-amended soil.Plant cover of colonizing vegetation was enhanced by amendments,but was independent of amendment doses.Changes in soil properties from 2003 to 2011 showed that the first amendment application of DO2 caused a high differentiation between all the amendment treatments and the NA treatment.After the second application of DO2,soil pH and TOC continued increasing slowly.Further two applications of amendments(DO4) caused differences only in the organic treatments.Plant cover increased over time in all the treatments including NA.It could be concluded that the slow and steady natural remediation of this soil could be enhanced by amendment application(ANR).