A micro electric vehicle (micro-EV) is a small car with one or two seats designed for short-to-medium-distance trips. Micro-EVs produce relatively less pollution during operation and, due to their compact size, offer greater mobility in narrow areas compared conventional transportation. These advantages have led continuous increase the number of micro-EVs. However, battery capacity results limited driving range per charge, and restrictions on power speed lead lower performance. Due these...

While automated-driving technology is advancing rapidly, human-centered research still in its early stages. Research on negative user responses to automated driving particularly limited complex roadway environments such as roundabouts, where decisions typically depend driver judgment and traffic conditions. In these environments, vehicles may exhibit unstable behaviors, sudden stops or forced intersection entries. Since successful interaction between users systems critical for widespread...

Summary This paper presents the results of a study conducted to examine characteristics human‐centered design and pedestrians' perceptions street features. The main emphasis was determine existence empirical evidence that increases pedestrian satisfaction levels enhances community walkability. following approach applied in study: (i) existing research concerning walkable facility designs reviewed; (ii) survey data from interviews regarding urban streets as well detailed geometric features...

Safety interventions (e.g., median barriers, photo enforcement) and road features type width) can influence crash severity, frequency, or both. Both dimensions—crash frequency severity—are needed to obtain a full accounting of safety. Extensive literature common sense both dictate that crashes are not created equal, with fatalities costing society more than 1,000 times the cost property damage on average. Despite this glaring disparity, profession has unanimously embraced successfully...

This study focuses on the design and validation of an internally matched high-power amplifier monolithic microwave integrated circuit (MMIC) for Ku-band solid-state power (SSPA) system integration. The designed MMIC exhibits sufficient gain output characteristics, making it suitable SSPA applications. offers a compact cost-effective configuration by reducing number components, such as blocks, isolators, combiners. results show performance more than 40 W with considerably high saturated...

Factors affecting accident frequencies at 72 signalized intersections in the Gyeonggi-Do (province) over a four-year period (2007~2010) were explored using random parameters negative binomial model. The empirical results from comparison with fixed model show that outperforms its counterpart and provides fuller understanding of factors which determine intersections. In addition, elasticity marginal effect estimated to gain more insight into effects one-percent one-unit changes dependent...

While electric vehicles (EVs) continue to draw more attention as an alternative traditional fossil fuel vehicles, the relatively short driving range of EVs is often pointed out their biggest drawback. In terms energy consumption, one most energy-intensive systems in heating, ventilation, and air conditioning (HVAC) system. Most HVAC use On/Off or PID control for actuators, but these methods have low efficiency are difficult apply multiple-input multiple-output systems. this paper, we propose...

With the rapid advancements in automated driving technologies, there is a growing demand for commercialization of advanced vehicles. Through these we envision enjoying various types entertainment vehicles, apart from manual driving. To achieve widespread acceptance driving, appropriated interactions between users and systems must occur. From users’ perspective, vehicle be operated within comfort, safe, satisfying perception based on their personal style such as aggressive defensive Thus,...

This study aims to investigate left- and right-side merging sections on urban underground roads based virtual reality driving simulator experiments. The behaviors investigated were changed by acceleration lane in the section, including 100, 120, 140 m, considering current design guidelines. Typically, changing behavior was studied experiments using speed lateral placement driving. of more reduction occurred left-side than sections. In sections, rate decreased with length lane. cases...

Nighttime driving behavior differs from that during the day because of differences in driver's field view. At night, drivers must rely on their vehicle headlamps to illuminate roadway. It is essential then roadway delineation system provide appropriate lane guidance motorists when navigating a roadway, particularly one curvilinear. A nighttime experiment was conducted collect user perception data various pavement markings and markers applied horizontal curves. The effectiveness each marking...

Understanding the expected safety performance of rural signalized intersections is critical for ( a) identifying high-risk sites where observed substantially worse than performance, b) understanding influential factors associated with crashes, and c) predicting future helping plan safety-enhancing activities. These three activities are routinely conducted management planning purposes in jurisdictions throughout United States around world. This paper aims to develop baseline functions South...

It is well known that a roundabout an efficient and safe intersection. However, the safety generally influenced by given various conditions. This study analyzed effects of geometric traffic flow conditions on accident frequency at roundabouts, constructed in Korea since 2010. Many previous studies have investigated efficiency installation. not many specific influences individual elements roundabouts. Accordingly, this influencing variables based random parameter count model using data 199...

Black ice is one of the main causes traffic accidents in winter, and warning signs for black are generally ineffective because lack credible information. To overcome this limitation, new were developed using materials that change color response to different temperatures. The performance effects investigated by conducting driver behavior analysis. end, driving simulator experiments conducted with 37 participants two rural highway sections, i.e., a curve tangent. analysis results visual showed...

In this study, a random parameter Tobit regression model approach was used to account for the distinct censoring problem and unobserved heterogeneity in accident data. We rate data (continuous data) instead of frequency (discrete count address zero cell problems from where roadway segments do not have any recorded accidents over observed time period. The is also considered by using parameters, which are estimates that vary across observations fixed fixed/constant observations. Nine years...

회전교차로는 교차로 중앙의 원형교통섬을 우회하며 교차로를 통과하고, 진입차량이 회전차량에게 양보하는 방식으로 운영되는 유형이다. 교통운영 및 안전측면에서 다른 유형에 비해 효율적인 것으로 알려져 있다. 최근 국내에서는 매년 약 100여개의 회전교차로가 전국적으로 시범 설치 운영되어 모니터링 되고 본 연구에서는 분석용 교통시뮬레이션 프로그램임 SIDRA를 이용하여 교통류 조건에 따라 회전교차로 계획, 설계하기 위한 평면교차로 유형별 적정 교통량 기준을 마련하였다. 분석결과 방향별로 진입교통량이 100-150대/시 이상인 1차로 비신호교차로(TWSC, AWSC)와 400-500대/시 이하인 신호교차로 경우에는 전환에 효율화를 기대할 수 있는 분석되었다. 또한, 좌회전 교통류율이 30%가 넘는 교차로에서는 보다는 신호교차로를 설치함이 바람직한 이와 같은 회전교차로의 적정교통량 수준 산정결과는 도입의 적절한 위치 선정에 도움에 되어 활성화에 많은 도움이 될 있을 기대한다. A...

Personal mobility vehicles (PMVs) are the potential future travel mode, typically for “first-mile and last-mile trips,” in urban areas. Accordingly, popularity of PMVs is increasing, purpose using diversifying South Korea. Before revision law concerning PMVs, driving ways roads were not defined by regulations Therefore, most PMV users preferred to drive on sidewalks bicycle lanes avoid collisions with larger vehicles. Furthermore, have been involved many accidents. To solve these problems,...

A roundabout is generally known as an efficient, safe, and environmentally friendly intersection. Since 2010, the Korea government has taken lead in constructing roundabouts part of a special project. During that time, many ideas have been put forward to improve safety, operation, design such roundabouts. In terms improvements, it particularly important understand gap acceptance behavior. As such, we investigated behaviors at four based on field observation during both good weather rainy...

There is currently much debate regarding the effectiveness of driver license system in South Korea, due to numerous traffic crashes caused by drivers who are suspected having insufficient physical and mental abilities. Through present system, it quite difficult identify such indirectly through tests, as visual acuity since correlation results with driving performance remains unclear. The objective this study was investigate relationship between acuities for improving Korean system. In study,...

A variety of statistical models were generally considered to better understand the relationship between crash occurrences and diverse factors. However, most adapted fixed parameters which cannot incorporate time variation or sement-specific effects. To relieve this problem, study focuses on a traffic accident frequency model using random parameter negative binomial approach. This method allows for consideration unobserved heterogeneity in data that current popular methods such as Poisson...

The conflict between vehicles and pedestrians at crosswalks, defined as a potential collision that could lead to actual traffic accidents, is an important measure indicating the level of pedestrian safety. Past research, with advanced statistical methods, gathered calibrated data from historical accidents produce this policy indicator. To perform such analysis, however, requires considerable amount samples collected under controlled conditions. Putting aside difficulty creating condition, it...

Herein, an integrated device that comprises inorganic kesterite solar cells and Li-ion batteries (LIBs) has been proposed for application in fast photo-charging power systems. LiFePO 4 Li Ti 5 O 12 were selected as the battery electrode materials six connected series fabricated to satisfy charging voltage required LIBs. Photo-charging was conducted at rate of 1C (1.790 mAh g −1 ) 2.1 V. An energy conversion storage efficiency 3.87% acquired device, a over 70% observed Furthermore, by...

PURPOSES: Though the situation that roundabouts are actively constructed, researches on effect of focus mainly analysis expected effects using only traffic simulation operation. Considering such problems, this study is conducted to analyze various aspects based field observation studies. METHODS: This evaluated and analyzed from operation, safety, behavior by performing studies with six with/without signal controls pilot project areas for installed in 2010. RESULTS: Through results, it was...

This study explored factors affecting traffic accidents in roadway segments with and without lighting systems using a random parameter negative binomial model. sought to make up for shortcoming of the fixed model that constrained estimated parameters be across observations, by applying can take into account unobserved heterogeneity. Three variables had among nine significant systems, while seven eleven segment system parameters. The different influence interstate highway geometrics on...