The market for electric vehicles is growing due to the public's interest in the environment and t... more The market for electric vehicles is growing due to the public's interest in the environment and the expansion of electric vehicle support projects in terms of government policy. This study surveyed 2,332 people in Jeju, one of the nation's representative areas of electric vehicles, and the higher the perceived value in terms of the total cost of automobile ownership for electric vehicles, the higher the intention to purchase electric vehicles. The higher the level of knowledge and attachment, the higher the intention to purchase electric vehicles. While many previous studies considered economic value mainly as price, the study was conducted to approach economic value in terms of total cost of ownership. Marketing practitioners also look for practical contributions in that they can propose price framing so that customers can judge the economic value of the electric vehicle as a strategic way to increase the intention to purchase the electric vehicle, rather than just the purchase price. can see. In addition, the same research should be conducted in various regions besides Jeju, so that the research results can be generalized.
To better plan, operate, and maintain the transportation system in Virginia, this study identifie... more To better plan, operate, and maintain the transportation system in Virginia, this study identifies Virginia transportation professionals' planning-related data needs, obstacles to fulfilling those needs, and potential solutions for overcoming those obstacles. Based on interviews with practitioners, a survey of 182 professionals, and a review of data management practices in the literature, the study finds that needs vary by organizational type: whereas only 41% of the Virginia Department of Transportation (VDOT) survey respondents have at least one unmet data need, this percentage climbs to 70% for metropolitan planning organization and local respondents. When all respondents were asked to name, out of 51 databases, those that were needed but not available, almost one-fifth of all respondents cited three databases relating to infrastructure, safety, and operations; in Virginia these databases are known as roadway network system (RNS), Highway Safety Improvement Program (HSIP), and data maintained by the Traffic Operations Center (TOC), respectively. A primary obstacle to meeting data needs is data availability: some proprietary data owned by VDOT cannot legally be shared with external agencies, some datasets are restricted in how they can be shared due to security concerns, and some datasets can be shared but are not known to external partners. Other obstacles include data quality, time required to access datasets, and database diversity as the survey suggested that planners need access to a wider variety of databases than do other types of transportation professionals. Potential solutions documented in the report are to increase user awareness through seminars or the creation of a transportation data map, improve ease of access for select users through the use of virtual private networks, improve ease of use through providing a single location as a starting point for acquiring some publicly available existing data, and integrate databases in instances where common data elements allow such integration. In the short term, two recommended courses of action appear feasible: (1) conduct a workshop to make external partners and VDOT staff aware of some of these diverse databases, and (2) conduct periodic meetings of planning, information technology, and research staff to identify ways to enhance data sharing.
Predicted travel time is important factor to help commuters make route choices and departure time... more Predicted travel time is important factor to help commuters make route choices and departure time decisions. Especially, it has an effect of dispersing the demand on the road. Previous research have been focused on providing information on the expected arrival time for a single route with a link travel time prediction. There is a limit to the study of travel time prediction by different routes that affects user's actual decision making. In this study, we have studied long-term travel time prediction using route travel data. We used self-organizing map clustering algorithm and the input variables of the model were day of the week, weather, daily traffic volume. Long-term travel time prediction for the Jungbu Naeryuk expressway, Cheongwon-Sangju expressway, Gyeongbu expressway is conducted and prediction results of k-NN were used for comparison of the predicted results. The prediction error of the travel time for each route was reduced and it showed a high error reduction in the Jungbu Naeryuk Expressway which has the most traffic volume of Seoul-Daegu section. In this paper, we proposed a method to overcome the limitation of the link-based travel time prediction. It can be used for route choices and departure time decisions of individual commuters by providing reliable travel time prediction for each route.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
In this study, we describe the results of an analysis of the effectiveness of providing pedestria... more In this study, we describe the results of an analysis of the effectiveness of providing pedestrian safety services, in terms of reducing pedestrian traffic accidents. We conducted our analysis by investigating the speed of vehicles at two different demonstration points, where the same system and service were provided. For this purpose, we selected a child protection zone and a point on a general road section where a raised crossing is installed. We conducted vehicle speed surveys at the point adjacent to the crosswalk and the points where the driver is expected to be fully provided with information, in order to examine the change in vehicle approach speed, depending on the provision of the service. Overall, the analysis showed that the vehicle’s speed at the point and approaching speed decreased when the pedestrian safety service was provided; however, the effect was more pronounced in the child protection zone, considering the characteristics of the demonstration points. From these...
Journal of the Eastern Asia Society for Transportation Studies, 2008
In the feasibility analysis, Braess' Paradox results in the negative social benefit in spite ... more In the feasibility analysis, Braess' Paradox results in the negative social benefit in spite of adding transportation facilities. Consequently, it has been difficult to judge on the investment of SOC projects. This research aims to analyze the Braess' Paradox in the feasibility analysis and to seek a remedy for the Paradox. Several experiments were conducted on the simple network under the various conditions. From the experiments, following findings were validated: Braess' Paradox occurred only if travel demands met within certain intermediate range. In terms of traffic assignment method, the SO was more likely to reduce the effect of the Braess' Paradox than the UE. However, the Braess' Paradox in the benefit of operating cost saving occurred in all cases and the paradox in the total benefit continued. In order to solve the problem, new link cost function considered travel time and operating cost simultaneously were suggested. As a result, the negative benefit w...
The market for electric vehicles is growing due to the public's interest in the environment a... more The market for electric vehicles is growing due to the public's interest in the environment and the expansion of electric vehicle support projects in terms of government policy. This study surveyed 2,332 people in Jeju, one of the nation's representative areas of electric vehicles, and the higher the perceived value in terms of the total cost of automobile ownership for electric vehicles, the higher the intention to purchase electric vehicles. The higher the level of knowledge and attachment, the higher the intention to purchase electric vehicles. While many previous studies considered economic value mainly as price, the study was conducted to approach economic value in terms of total cost of ownership. Marketing practitioners also look for practical contributions in that they can propose price framing so that customers can judge the economic value of the electric vehicle as a strategic way to increase the intention to purchase the electric vehicle, rather than just the purc...
To better plan, operate, and maintain the transportation system in Virginia, this study identifie... more To better plan, operate, and maintain the transportation system in Virginia, this study identifies Virginia transportation professionals’ planning-related data needs, obstacles to fulfilling those needs, and potential solutions for overcoming those obstacles. Based on interviews with practitioners, a survey of 182 professionals, and a review of data management practices in the literature, the study finds that needs vary by organizational type: whereas only 41% of the Virginia Department of Transportation (VDOT) survey respondents have at least one unmet data need, this percentage climbs to 70% for metropolitan planning organization and local respondents. When all respondents were asked to name, out of 51 databases, those that were needed but not available, almost one-fifth of all respondents cited three databases relating to infrastructure, safety, and operations; in Virginia these databases are known as roadway network system (RNS), Highway Safety Improvement Program (HSIP), and da...
Implementation of Cu interconnects into Silicon Integrated Circuits (IC's) has been instrumental ... more Implementation of Cu interconnects into Silicon Integrated Circuits (IC's) has been instrumental in the continuing improvement of IC device performance. Copper as a well known Gate Oxide Integrity (GOI) killer [1,2] requires extensive protocols to minimize the possibility of cross contamination. Despite such protocols the risk for cross contamination exists, and consequently there is the need for in-line Cu cross-contamination detection metrology. Preferably the metrology will be non-destructive, fast, and capable of mapping on product wafers. Up to now the most common approaches for monitoring Cu contamination in IC fabrication lines either measure Cu in the bulk Si, which is not applicable to Cu cross-contamination monitoring because Back-End-of-the-Line thermal budgets restrict the ability to diffuse the surface Cu into the bulk Si; or the techniques are not optimal for in-line monitoring due to their destructive, time-consuming, or costly nature. In this work we demonstrate for the first time the application of the ac-Surface Photo Voltage (ac-SPV) surface lifetime approach [3] to in-line, full wafer coverage mapping of low level (<lE9cm-2) surface Cu contamination. The low level sensitivity is achieved through integration of a novel preferential surface Cu activation procedure into a production ready metrology system. Furthermore, because the metrology is noncontact (utilizing edge-grip handling) and non-destructive, it is directly applicable to measurement of production wafers. In-line fab data acquired using this metrology is presented and compared to data from Inductively Coupled Plasma Mass Spectroscopy (ICP-MS).
We present micro corona - Kelvin data acquired on ZrO2/Al2O3/ZrO2 (ZAZ) dielectric stacks in the ... more We present micro corona - Kelvin data acquired on ZrO2/Al2O3/ZrO2 (ZAZ) dielectric stacks in the active capacitor cell areas of advanced DRAM production wafers. Specifically, we compare micro - SASS (Self Adjusting Steady State) voltage data measured on patterned wafers to similarly acquired data on blanket ZAZ dielectric stacks. From this comparison, we formulate a model that interprets active area micro - SASS voltage as being proportional to the ZAZ dielectric stack capacitance. Validation of the method and accompanying model is made through measurement of a production baseline that demonstrates sensitivity to various process deviations. Further validation is achieved through comparison of in-line active cell area micro - SASS data to End - of - the - Line Electrical Parametric Measurement Capacitance and Breakdown Voltage data. We also demonstrate that the method, which includes corona charging and measurement on the active device areas, does not adversely impact final device yi...
Transportation Research Record: Journal of the Transportation Research Board, 2013
National and regional household travel surveys have conventionally sampled landline telephone hou... more National and regional household travel surveys have conventionally sampled landline telephone households through list-assisted random digit dialing. However, recent increases in “mobile phone-only” households result in either noncoverage or undercoverage of a growing segment of the population. This result could cause a substantial bias in the representativeness of travel behavior toward the target population. To cover mobile phone-only households, an address-based sampling method is of interest. This study explores whether the characteristics and travel behavior of mobile phone-only households differ from those of households with landline telephones. In addition, this study quantifies the extent of noncoverage errors in the surveys in respondents’ travel behavior. Along with census data, the mobile phone-only sample (N = 2,988) was compared with the landline telephone sample (N = 7,774) drawn from the 2008 National Capital Region Household Travel Survey. Results show that the mobile...
The market for electric vehicles is growing due to the public's interest in the environment and t... more The market for electric vehicles is growing due to the public's interest in the environment and the expansion of electric vehicle support projects in terms of government policy. This study surveyed 2,332 people in Jeju, one of the nation's representative areas of electric vehicles, and the higher the perceived value in terms of the total cost of automobile ownership for electric vehicles, the higher the intention to purchase electric vehicles. The higher the level of knowledge and attachment, the higher the intention to purchase electric vehicles. While many previous studies considered economic value mainly as price, the study was conducted to approach economic value in terms of total cost of ownership. Marketing practitioners also look for practical contributions in that they can propose price framing so that customers can judge the economic value of the electric vehicle as a strategic way to increase the intention to purchase the electric vehicle, rather than just the purchase price. can see. In addition, the same research should be conducted in various regions besides Jeju, so that the research results can be generalized.
To better plan, operate, and maintain the transportation system in Virginia, this study identifie... more To better plan, operate, and maintain the transportation system in Virginia, this study identifies Virginia transportation professionals' planning-related data needs, obstacles to fulfilling those needs, and potential solutions for overcoming those obstacles. Based on interviews with practitioners, a survey of 182 professionals, and a review of data management practices in the literature, the study finds that needs vary by organizational type: whereas only 41% of the Virginia Department of Transportation (VDOT) survey respondents have at least one unmet data need, this percentage climbs to 70% for metropolitan planning organization and local respondents. When all respondents were asked to name, out of 51 databases, those that were needed but not available, almost one-fifth of all respondents cited three databases relating to infrastructure, safety, and operations; in Virginia these databases are known as roadway network system (RNS), Highway Safety Improvement Program (HSIP), and data maintained by the Traffic Operations Center (TOC), respectively. A primary obstacle to meeting data needs is data availability: some proprietary data owned by VDOT cannot legally be shared with external agencies, some datasets are restricted in how they can be shared due to security concerns, and some datasets can be shared but are not known to external partners. Other obstacles include data quality, time required to access datasets, and database diversity as the survey suggested that planners need access to a wider variety of databases than do other types of transportation professionals. Potential solutions documented in the report are to increase user awareness through seminars or the creation of a transportation data map, improve ease of access for select users through the use of virtual private networks, improve ease of use through providing a single location as a starting point for acquiring some publicly available existing data, and integrate databases in instances where common data elements allow such integration. In the short term, two recommended courses of action appear feasible: (1) conduct a workshop to make external partners and VDOT staff aware of some of these diverse databases, and (2) conduct periodic meetings of planning, information technology, and research staff to identify ways to enhance data sharing.
Predicted travel time is important factor to help commuters make route choices and departure time... more Predicted travel time is important factor to help commuters make route choices and departure time decisions. Especially, it has an effect of dispersing the demand on the road. Previous research have been focused on providing information on the expected arrival time for a single route with a link travel time prediction. There is a limit to the study of travel time prediction by different routes that affects user's actual decision making. In this study, we have studied long-term travel time prediction using route travel data. We used self-organizing map clustering algorithm and the input variables of the model were day of the week, weather, daily traffic volume. Long-term travel time prediction for the Jungbu Naeryuk expressway, Cheongwon-Sangju expressway, Gyeongbu expressway is conducted and prediction results of k-NN were used for comparison of the predicted results. The prediction error of the travel time for each route was reduced and it showed a high error reduction in the Jungbu Naeryuk Expressway which has the most traffic volume of Seoul-Daegu section. In this paper, we proposed a method to overcome the limitation of the link-based travel time prediction. It can be used for route choices and departure time decisions of individual commuters by providing reliable travel time prediction for each route.
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
In this study, we describe the results of an analysis of the effectiveness of providing pedestria... more In this study, we describe the results of an analysis of the effectiveness of providing pedestrian safety services, in terms of reducing pedestrian traffic accidents. We conducted our analysis by investigating the speed of vehicles at two different demonstration points, where the same system and service were provided. For this purpose, we selected a child protection zone and a point on a general road section where a raised crossing is installed. We conducted vehicle speed surveys at the point adjacent to the crosswalk and the points where the driver is expected to be fully provided with information, in order to examine the change in vehicle approach speed, depending on the provision of the service. Overall, the analysis showed that the vehicle’s speed at the point and approaching speed decreased when the pedestrian safety service was provided; however, the effect was more pronounced in the child protection zone, considering the characteristics of the demonstration points. From these...
Journal of the Eastern Asia Society for Transportation Studies, 2008
In the feasibility analysis, Braess' Paradox results in the negative social benefit in spite ... more In the feasibility analysis, Braess' Paradox results in the negative social benefit in spite of adding transportation facilities. Consequently, it has been difficult to judge on the investment of SOC projects. This research aims to analyze the Braess' Paradox in the feasibility analysis and to seek a remedy for the Paradox. Several experiments were conducted on the simple network under the various conditions. From the experiments, following findings were validated: Braess' Paradox occurred only if travel demands met within certain intermediate range. In terms of traffic assignment method, the SO was more likely to reduce the effect of the Braess' Paradox than the UE. However, the Braess' Paradox in the benefit of operating cost saving occurred in all cases and the paradox in the total benefit continued. In order to solve the problem, new link cost function considered travel time and operating cost simultaneously were suggested. As a result, the negative benefit w...
The market for electric vehicles is growing due to the public's interest in the environment a... more The market for electric vehicles is growing due to the public's interest in the environment and the expansion of electric vehicle support projects in terms of government policy. This study surveyed 2,332 people in Jeju, one of the nation's representative areas of electric vehicles, and the higher the perceived value in terms of the total cost of automobile ownership for electric vehicles, the higher the intention to purchase electric vehicles. The higher the level of knowledge and attachment, the higher the intention to purchase electric vehicles. While many previous studies considered economic value mainly as price, the study was conducted to approach economic value in terms of total cost of ownership. Marketing practitioners also look for practical contributions in that they can propose price framing so that customers can judge the economic value of the electric vehicle as a strategic way to increase the intention to purchase the electric vehicle, rather than just the purc...
To better plan, operate, and maintain the transportation system in Virginia, this study identifie... more To better plan, operate, and maintain the transportation system in Virginia, this study identifies Virginia transportation professionals’ planning-related data needs, obstacles to fulfilling those needs, and potential solutions for overcoming those obstacles. Based on interviews with practitioners, a survey of 182 professionals, and a review of data management practices in the literature, the study finds that needs vary by organizational type: whereas only 41% of the Virginia Department of Transportation (VDOT) survey respondents have at least one unmet data need, this percentage climbs to 70% for metropolitan planning organization and local respondents. When all respondents were asked to name, out of 51 databases, those that were needed but not available, almost one-fifth of all respondents cited three databases relating to infrastructure, safety, and operations; in Virginia these databases are known as roadway network system (RNS), Highway Safety Improvement Program (HSIP), and da...
Implementation of Cu interconnects into Silicon Integrated Circuits (IC's) has been instrumental ... more Implementation of Cu interconnects into Silicon Integrated Circuits (IC's) has been instrumental in the continuing improvement of IC device performance. Copper as a well known Gate Oxide Integrity (GOI) killer [1,2] requires extensive protocols to minimize the possibility of cross contamination. Despite such protocols the risk for cross contamination exists, and consequently there is the need for in-line Cu cross-contamination detection metrology. Preferably the metrology will be non-destructive, fast, and capable of mapping on product wafers. Up to now the most common approaches for monitoring Cu contamination in IC fabrication lines either measure Cu in the bulk Si, which is not applicable to Cu cross-contamination monitoring because Back-End-of-the-Line thermal budgets restrict the ability to diffuse the surface Cu into the bulk Si; or the techniques are not optimal for in-line monitoring due to their destructive, time-consuming, or costly nature. In this work we demonstrate for the first time the application of the ac-Surface Photo Voltage (ac-SPV) surface lifetime approach [3] to in-line, full wafer coverage mapping of low level (<lE9cm-2) surface Cu contamination. The low level sensitivity is achieved through integration of a novel preferential surface Cu activation procedure into a production ready metrology system. Furthermore, because the metrology is noncontact (utilizing edge-grip handling) and non-destructive, it is directly applicable to measurement of production wafers. In-line fab data acquired using this metrology is presented and compared to data from Inductively Coupled Plasma Mass Spectroscopy (ICP-MS).
We present micro corona - Kelvin data acquired on ZrO2/Al2O3/ZrO2 (ZAZ) dielectric stacks in the ... more We present micro corona - Kelvin data acquired on ZrO2/Al2O3/ZrO2 (ZAZ) dielectric stacks in the active capacitor cell areas of advanced DRAM production wafers. Specifically, we compare micro - SASS (Self Adjusting Steady State) voltage data measured on patterned wafers to similarly acquired data on blanket ZAZ dielectric stacks. From this comparison, we formulate a model that interprets active area micro - SASS voltage as being proportional to the ZAZ dielectric stack capacitance. Validation of the method and accompanying model is made through measurement of a production baseline that demonstrates sensitivity to various process deviations. Further validation is achieved through comparison of in-line active cell area micro - SASS data to End - of - the - Line Electrical Parametric Measurement Capacitance and Breakdown Voltage data. We also demonstrate that the method, which includes corona charging and measurement on the active device areas, does not adversely impact final device yi...
Transportation Research Record: Journal of the Transportation Research Board, 2013
National and regional household travel surveys have conventionally sampled landline telephone hou... more National and regional household travel surveys have conventionally sampled landline telephone households through list-assisted random digit dialing. However, recent increases in “mobile phone-only” households result in either noncoverage or undercoverage of a growing segment of the population. This result could cause a substantial bias in the representativeness of travel behavior toward the target population. To cover mobile phone-only households, an address-based sampling method is of interest. This study explores whether the characteristics and travel behavior of mobile phone-only households differ from those of households with landline telephones. In addition, this study quantifies the extent of noncoverage errors in the surveys in respondents’ travel behavior. Along with census data, the mobile phone-only sample (N = 2,988) was compared with the landline telephone sample (N = 7,774) drawn from the 2008 National Capital Region Household Travel Survey. Results show that the mobile...
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