Milling Ti alloy is a very difficult technology. The primary problem is that the miller wear is very rapid and makes the miller break or rapture. Although cutting fluid is mainly used to reduce friction and temperatur...Milling Ti alloy is a very difficult technology. The primary problem is that the miller wear is very rapid and makes the miller break or rapture. Although cutting fluid is mainly used to reduce friction and temperature in cutting area to enhance tool life, it is the largest source of environmental pollution. To develop a technology for the clean and efficient milling Ti alloys, nitrogen gas is used as a cutting media in this paper. Based on lots of experiments and researches, the tool life and wear mechanism of high speed steel miller is analyzed. A conclusion is drawn that, milling with nitrogen gas media yields much longer tool life than dry milling. Tool life equations (Taylor′s equations) are derived for both milling types.展开更多
In the research, trees along 42 roads in Chongqing were explored and es- timated in terms of aesthetics, and aesthetic tendency and major influential factors of aesthetic value of street greenbelts in Chongqing arteri...In the research, trees along 42 roads in Chongqing were explored and es- timated in terms of aesthetics, and aesthetic tendency and major influential factors of aesthetic value of street greenbelts in Chongqing arterial roads were estimated with phychophysical method to establish SBE model of arterial road greenbelts land- scape.展开更多
Considering the decision-making variables of the capacities of branch roads and the optimization targets of lowering the saturation of arterial roads and the reconstruction expense of branch roads, the bi-level progra...Considering the decision-making variables of the capacities of branch roads and the optimization targets of lowering the saturation of arterial roads and the reconstruction expense of branch roads, the bi-level programming model for reconstructing the branch roads was set up. The upper level model was for determining the enlarged capacities of the branch roads, and the lower level model was for calculating the flows of road sections via the user equilibrium traffic assignment method. The genetic algorithm for solving the bi-level model was designed to obtain the reconstruction capacities of the branch roads. The results show that by the bi-level model and its algorithm, the optimum scheme of urban branch roads reconstruction can be gained, which reduces the saturation of arterial roads apparently, and alleviates traffic congestion. In the data analysis the arterial saturation decreases from 1.100 to 0.996, which verifies the micro-circulation transportation's function of urban branch road network.展开更多
The highway construction inevitably may cause certain influence to the cultural heritage and the natural environment along the route, particularly in design stage; if the route selection is unreasonable, it will certa...The highway construction inevitably may cause certain influence to the cultural heritage and the natural environment along the route, particularly in design stage; if the route selection is unreasonable, it will certainly impact the natural resource seriously along the route. On the contrary, good design can reasonably develop, use, protect and promote the value of cultural heritage and natural environment. Changsha to Jishou （Chang-Ji） freeway is one section of Changsha to Chongqing freeway, which is one of the eight big west channels as planned in China; two cities of Changde and Huaihua and one autonomous region of Xianxi in western Hunan province, along which the cultural heritage and the natural resource are rich, and the natural landscape is exquisite. This paper investigates and analyzes the natural resources along the route of Chang-Ji freeway, puts forward some protection design evaluation indexes for mountain area freeway by the thought of context sensitive design. At last, the paper introduces the effect of applying the indexes to select route of Chang-Ji freeway.展开更多
Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum...Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum bandwidth is proposed.By using the pre-set parameters of a common cycle,green/red duration and known parameters of bus dwell time distribution,link length and vehicle speed and solving the mixed-integer-linear programming and optimizing the signal offsets,the model obtains the signal control parameters of the green bands both of social vehicles and buses.Finally,taking Wangjiang Road in Hefei as an example,simulation and evaluation are carried out by VISSIM.The results show that the new model has 15.2%and 13.2%reduction in average person delay and number of stops,respectively,compared with the traditional coordinated control method.展开更多
This paper focuses on the relationship between firm risk profile, agency incentives and corporate performance using correlation study and cross-sectional approach. We conceptualise firm risk profile using the balanced...This paper focuses on the relationship between firm risk profile, agency incentives and corporate performance using correlation study and cross-sectional approach. We conceptualise firm risk profile using the balanced score card and differ from previous studies, on the above variables, by capturing the perceptual sets of strategic leadership of Ugandan firms who are members of corporate governance of Uganda. We post a significant negative relationship between firm risk profile and corporate performance, a significant negative relationship between firm risk profile and agency incentives and a positive relationship between agency incentives and corporate performance By employing Joseph and Scott （2006）＇s utilization of the balanced score card to identify the four forms of firm risk （namely, financial, customer, internal and learning and growth risks）, our results support the application of agency theory as a relevant theoretical framework for dealing with managers who are risk averse.展开更多
Fostering the use of transit has been broadly accepted as an effective way to improve social equity and reduce the externalities caused by transportation. In the great body of transit literature, many have focused on ...Fostering the use of transit has been broadly accepted as an effective way to improve social equity and reduce the externalities caused by transportation. In the great body of transit literature, many have focused on the improvement of transfer efficiency. However, investigation on transit transfer efficiency is still lacking for medium sized cities or suburban areas that have sprawled from city centers. The special features associated with such an urban form lead to unique travel patterns and bus operations. This work develops a process to improve bus transfer efficiency for small conurbations considering their special characteristics. A case study of New York's Capital District is used to illustrate the proposed method. Results show that the transfer waiting time can be remarkably shortened. The proposed method can be widely adapted to other transit systems in small conurbations.展开更多
The health impacts of tobacco consumption are well documented and have gained acceptance worldwide. Today, a substantial, preventable burden of tobacco attributable diseases exists in most countries, though in most of...The health impacts of tobacco consumption are well documented and have gained acceptance worldwide. Today, a substantial, preventable burden of tobacco attributable diseases exists in most countries, though in most of the cases, unknown. Smoking accounts for almost half of the deaths in middle age in some regions. In Uganda, translating findings into policy action is slow and involves several stakeholders. It will continue to require support from tobacco control campaign groups. This paper analyses secondary literature on tobacco smoking and later provides an appropriate medium based communication strategy that can be adopted to counteract the persuasive smoking evil adverts of tobacco companies as well as creating awareness among the population of the health impacts caused by smoking.展开更多
Lignite and sub-bituminous coals from western U.S. contain high amounts of moisture （sub-bituminous： 15%-30%, lignites： 25%-40%）. German and Australian lignites （brown coals） have even higher moisture content, 5...Lignite and sub-bituminous coals from western U.S. contain high amounts of moisture （sub-bituminous： 15%-30%, lignites： 25%-40%）. German and Australian lignites （brown coals） have even higher moisture content, 50% and 60%, respectively. The high moisture content causes a reduction in plant performance and higher emissions, compared to the bituminous （hard） coals. Despite their high-moisture content, lignite and sub-bituminous coals from the western U.S. and worldwide are attractive due to their abundance, low cost, low NOx and SOx emissions, and high reactivity. A novel low-temperature coal drying process employing a fluidized bed dryer and waste heat was developed in the U.S. by a team led by GRE （Great River Energy）. Demonstration of the technology was conducted with the U.S. Department of Energy and GRE funding at Coal Creek Station Unit 1. Following the successful demonstration, the low-temperature coal drying technology was commercialized by GRE under the trade name DryFiningTM fuel enhancement process and implemented at both units at Coal Creek Station. The coal drying system at Coal Creek has been in a continuous commercial operation since December 2009. By implementing DryFining at Coal Creek, GRE avoided $366 million in capital expenditures, which would otherwise be needed to comply with emission regulations. Four years of operating experience is described in this paper.展开更多
Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of econom...Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society.This article explores an effective mechanism of managing resource and environment in China.It examines some major resource and environmental issues,and constructs a framework of institution innovation to cover three sectors(government,market and society) . In addition,the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period.We argue that the combination of market regulation,government intervention and public participation is an effective way of allocating resource and protecting environment. Some suggestions are put forward to balance the relationship between them,including coordinating role of government and market,building platform for market operation and creating an atmosphere of public participation.展开更多
To enhance the electro-optic (EO) modulation efficiency and realize the impedance-matching, a polymer-on-silicon multi-mode interference (MMI) Mach-Zehnder interferometer (MZI)-based electro-optic (EO) switch is desig...To enhance the electro-optic (EO) modulation efficiency and realize the impedance-matching, a polymer-on-silicon multi-mode interference (MMI) Mach-Zehnder interferometer (MZI)-based electro-optic (EO) switch is designed and optimized. Under the central operation wavelength of 1550 nm, the driving voltages of the designed switch are 0 and ±1.375 V, respectively, with a short active region length of 5 mm, and the characteristic impedance of the electrode is about 49.6 ?. The manufacture tolerance is analyzed for instructing the device fabrication. The results show that to realize ideal switching function, high fabrication accuracy on the buffer thickness, core thickness, electrode width and MMI waveguide width is extremely required, and a small voltage drift of-0.03-0.05 V is also expected for reducing the crosstalk to less than-30 dB. The allowed 3 dB bandwidth is 60 nm, and within this spectrum range, the insertion loss and crosstalk are less than 6.71 dB and-30 dB, respectively.展开更多
China and neighboring countries start new cooperation pattern in the Lancang-Mekong River regionThe strongest El Ni？o weather cycle on record has exacerbated drought in the Mekong River area since the end of last year.
文摘Milling Ti alloy is a very difficult technology. The primary problem is that the miller wear is very rapid and makes the miller break or rapture. Although cutting fluid is mainly used to reduce friction and temperature in cutting area to enhance tool life, it is the largest source of environmental pollution. To develop a technology for the clean and efficient milling Ti alloys, nitrogen gas is used as a cutting media in this paper. Based on lots of experiments and researches, the tool life and wear mechanism of high speed steel miller is analyzed. A conclusion is drawn that, milling with nitrogen gas media yields much longer tool life than dry milling. Tool life equations (Taylor′s equations) are derived for both milling types.
文摘In the research, trees along 42 roads in Chongqing were explored and es- timated in terms of aesthetics, and aesthetic tendency and major influential factors of aesthetic value of street greenbelts in Chongqing arterial roads were estimated with phychophysical method to establish SBE model of arterial road greenbelts land- scape.
基金Project(2006CB705507) supported by the National Basic Research and Development Program of ChinaProject(20060533036) supported by the Specialized Research Foundation for the Doctoral Program of Higher Education of China
文摘Considering the decision-making variables of the capacities of branch roads and the optimization targets of lowering the saturation of arterial roads and the reconstruction expense of branch roads, the bi-level programming model for reconstructing the branch roads was set up. The upper level model was for determining the enlarged capacities of the branch roads, and the lower level model was for calculating the flows of road sections via the user equilibrium traffic assignment method. The genetic algorithm for solving the bi-level model was designed to obtain the reconstruction capacities of the branch roads. The results show that by the bi-level model and its algorithm, the optimum scheme of urban branch roads reconstruction can be gained, which reduces the saturation of arterial roads apparently, and alleviates traffic congestion. In the data analysis the arterial saturation decreases from 1.100 to 0.996, which verifies the micro-circulation transportation's function of urban branch road network.
基金Acknowledgement： The authors appreciate the support of the West Transportation Construction Science and Technology of China （No. 200331879805） and Hunan Provincial Natural Science Foundation of China （No. 07JJ3111）.
文摘The highway construction inevitably may cause certain influence to the cultural heritage and the natural environment along the route, particularly in design stage; if the route selection is unreasonable, it will certainly impact the natural resource seriously along the route. On the contrary, good design can reasonably develop, use, protect and promote the value of cultural heritage and natural environment. Changsha to Jishou （Chang-Ji） freeway is one section of Changsha to Chongqing freeway, which is one of the eight big west channels as planned in China; two cities of Changde and Huaihua and one autonomous region of Xianxi in western Hunan province, along which the cultural heritage and the natural resource are rich, and the natural landscape is exquisite. This paper investigates and analyzes the natural resources along the route of Chang-Ji freeway, puts forward some protection design evaluation indexes for mountain area freeway by the thought of context sensitive design. At last, the paper introduces the effect of applying the indexes to select route of Chang-Ji freeway.
基金The National Natural Science Foundation of China(No.51878236)。
文摘Considering the difference in driving parameters of buses and social vehicles on the arterial,an arterial traffic signal coordination model that takes into account social vehicles and buses on the basis of the maximum bandwidth is proposed.By using the pre-set parameters of a common cycle,green/red duration and known parameters of bus dwell time distribution,link length and vehicle speed and solving the mixed-integer-linear programming and optimizing the signal offsets,the model obtains the signal control parameters of the green bands both of social vehicles and buses.Finally,taking Wangjiang Road in Hefei as an example,simulation and evaluation are carried out by VISSIM.The results show that the new model has 15.2%and 13.2%reduction in average person delay and number of stops,respectively,compared with the traditional coordinated control method.
文摘This paper focuses on the relationship between firm risk profile, agency incentives and corporate performance using correlation study and cross-sectional approach. We conceptualise firm risk profile using the balanced score card and differ from previous studies, on the above variables, by capturing the perceptual sets of strategic leadership of Ugandan firms who are members of corporate governance of Uganda. We post a significant negative relationship between firm risk profile and corporate performance, a significant negative relationship between firm risk profile and agency incentives and a positive relationship between agency incentives and corporate performance By employing Joseph and Scott （2006）＇s utilization of the balanced score card to identify the four forms of firm risk （namely, financial, customer, internal and learning and growth risks）, our results support the application of agency theory as a relevant theoretical framework for dealing with managers who are risk averse.
文摘Fostering the use of transit has been broadly accepted as an effective way to improve social equity and reduce the externalities caused by transportation. In the great body of transit literature, many have focused on the improvement of transfer efficiency. However, investigation on transit transfer efficiency is still lacking for medium sized cities or suburban areas that have sprawled from city centers. The special features associated with such an urban form lead to unique travel patterns and bus operations. This work develops a process to improve bus transfer efficiency for small conurbations considering their special characteristics. A case study of New York's Capital District is used to illustrate the proposed method. Results show that the transfer waiting time can be remarkably shortened. The proposed method can be widely adapted to other transit systems in small conurbations.
文摘The health impacts of tobacco consumption are well documented and have gained acceptance worldwide. Today, a substantial, preventable burden of tobacco attributable diseases exists in most countries, though in most of the cases, unknown. Smoking accounts for almost half of the deaths in middle age in some regions. In Uganda, translating findings into policy action is slow and involves several stakeholders. It will continue to require support from tobacco control campaign groups. This paper analyses secondary literature on tobacco smoking and later provides an appropriate medium based communication strategy that can be adopted to counteract the persuasive smoking evil adverts of tobacco companies as well as creating awareness among the population of the health impacts caused by smoking.
文摘Lignite and sub-bituminous coals from western U.S. contain high amounts of moisture （sub-bituminous： 15%-30%, lignites： 25%-40%）. German and Australian lignites （brown coals） have even higher moisture content, 50% and 60%, respectively. The high moisture content causes a reduction in plant performance and higher emissions, compared to the bituminous （hard） coals. Despite their high-moisture content, lignite and sub-bituminous coals from the western U.S. and worldwide are attractive due to their abundance, low cost, low NOx and SOx emissions, and high reactivity. A novel low-temperature coal drying process employing a fluidized bed dryer and waste heat was developed in the U.S. by a team led by GRE （Great River Energy）. Demonstration of the technology was conducted with the U.S. Department of Energy and GRE funding at Coal Creek Station Unit 1. Following the successful demonstration, the low-temperature coal drying technology was commercialized by GRE under the trade name DryFiningTM fuel enhancement process and implemented at both units at Coal Creek Station. The coal drying system at Coal Creek has been in a continuous commercial operation since December 2009. By implementing DryFining at Coal Creek, GRE avoided $366 million in capital expenditures, which would otherwise be needed to comply with emission regulations. Four years of operating experience is described in this paper.
基金funded by important direction of Chinese Academy of Sciences Knowledge Innovation Project(Grant no.kzcx2-yw-321)the National Natural Science Funds of Research on Water Pollution Effects of Industrial Agglomeration and Spatial Optimization-Case of Sunan Area(Grant no. 70703033)
文摘Along with the rapid growth of economy in the postreform period after 1979,China has faced severe problems of resource overusing and environmental degradation which would threaten the sustainable development of economy and society.This article explores an effective mechanism of managing resource and environment in China.It examines some major resource and environmental issues,and constructs a framework of institution innovation to cover three sectors(government,market and society) . In addition,the article analyzes their experience and evaluation in resource management and environmental conservation during the transitional period.We argue that the combination of market regulation,government intervention and public participation is an effective way of allocating resource and protecting environment. Some suggestions are put forward to balance the relationship between them,including coordinating role of government and market,building platform for market operation and creating an atmosphere of public participation.
基金supported by the National Natural Science Foundation of China (Nos. 60706011, 60807029, and 61077041)the Fund of Ministry of Education of China (Nos. 20070183087 and 20090061110041)+1 种基金the Science and Technology Fund of Jilin Province of China (No.20080125)the National Basic Research Development Program of China (No. 2006CB302803)
文摘To enhance the electro-optic (EO) modulation efficiency and realize the impedance-matching, a polymer-on-silicon multi-mode interference (MMI) Mach-Zehnder interferometer (MZI)-based electro-optic (EO) switch is designed and optimized. Under the central operation wavelength of 1550 nm, the driving voltages of the designed switch are 0 and ±1.375 V, respectively, with a short active region length of 5 mm, and the characteristic impedance of the electrode is about 49.6 ?. The manufacture tolerance is analyzed for instructing the device fabrication. The results show that to realize ideal switching function, high fabrication accuracy on the buffer thickness, core thickness, electrode width and MMI waveguide width is extremely required, and a small voltage drift of-0.03-0.05 V is also expected for reducing the crosstalk to less than-30 dB. The allowed 3 dB bandwidth is 60 nm, and within this spectrum range, the insertion loss and crosstalk are less than 6.71 dB and-30 dB, respectively.
文摘China and neighboring countries start new cooperation pattern in the Lancang-Mekong River regionThe strongest El Ni？o weather cycle on record has exacerbated drought in the Mekong River area since the end of last year.
