• Journal of Advanced Navigation Technology
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• v.24 no.5
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• pp.358-367
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• 2020

With the increases of average commuting time of office workers in the Seoul metropolitan area and the cost of traffic congestion on roads, the need for new transportation is increasing and urban air mobility (UAM) is emerging as an alternative. Therefore, in this paper, the vertiport locations were selected and routes were established using population, traffic and commuting data of Seoul and Gyeonggi Province. Vector thrust type and multicopter type of eVTOL compatible for UAM were selected by analyzing the types of eVTOLand time required for selected routes was calculated. In addition, the time required when we utilize other transportations was compared with UAM. Finally, it was verified that the commuting time can be sharply reduced when we use UAM.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.115-121
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• 2020

This study aims to investigate the effects of restrictions in economic activity on the spread of COVID-19 in the Philippines. This research employs daily time-series data of confirmed new COVID-19 cases, Apple mobility trends (i.e., use of public transport to destinations, volume of people driving, and amount of walking to destinations) and Google community mobility (i.e., visits to transit stations, visits to workplaces, and staying-at-home) indicators covering the period February 17 to September 11, 2020. The analysis starts by establishing the correlation pattern of new confirmed COVID-19 daily infections to each independent variable. The results show negative linear correlation of the number of new COVID-19 daily infections with less visit to transit station, increase stay-at-home, less use of public transport, and less amount of walking to destinations. Interestingly, the number of new COVID-19 daily infections indicates some form of positive linear correlation with visits to workplaces and volume of people driving. Moreover, employing robust least square regression via the method of MM-estimation, major findings reveal that across mobility measures, staying-at-home has the highest impact on reducing the spread of COVID-19, followed by visiting transit stations less, less use of public transport, less amount of walking, and less workplace visits.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.107-119
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• 2013

This paper reinforced security under the network evaluation of wire wireless integration of NEMO (NEwork MObility) supporting mobility and network-based PMIPv6 (Proxy Mobile IPv6). It also proposes $SK-L^2AS$ (Symmetric Key-Based Local-Lighted Authentication Scheme) based on simple key which reduces code calculation and authentication delay costs. Moreover, fast handover technique was also adopted to reduce handover delay time in PMIPv6 and X-FPMIPv6 (eXtension of Fast Handover for PMIPv6) was used to support global mobility. In addition, AX-FPMIPv6 (Authentication eXtension of Fast Handover for PMIPv6) is proposed which integrated $SK-L^2AS$ and X-FPMIPv6 by applying Piggybacks method to reduce the overhead of authentication and signaling. The AX-FPMIPv6 technique suggested in this paper shows that this technique is better than the existing schemes in authentication and handover delay according to the performance analysis.

• Journal of Advanced Information Technology and Convergence
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• v.10 no.2
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• pp.73-81
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• 2020

The number of mobile devices roaming into a ubiquitous city (u-city) continues to rise as wireless systems have been widely deployed. The number of mobile devices also varies with time, and they tend to frequently change their locations. In addition, the available wireless access networks may belong to different domains, administrations, management, and internet service providers (ISPs). A fusion of overlapping heterogeneous wireless access networks (e.g., WiMax, Wi-Fi, LTE, etc.) serves the u-city in order to reach different coverage. In this context, technical challenges arise in mobility management for heterogeneous networks to realize their potential coverage and capacity benefits. This paper deals with the analysis of a decentralized mobility management support for u-City wireless network infrastructure. This scheme takes advantage of the features of the fully-distributed model of networked-based mobility management protocol to alleviate and realize the ubiquitous requirements of a u-City.

• Journal of the Korean Society of Costume
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• v.61 no.9
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• pp.97-113
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• 2011

To develop the work clothes for the employees in the mechatronics industry in South Korea, a questionnaire survey on many aspects of the work clothes such as type, color, detailed design and function preference of the subject employees has been carried out in the study. The results throughout the survey highlighted certain functions such as extensibility, thermal and air permeability of importance for the work clothing performance. To improve the discomfort caused by some work motions (i.e. squatting down, ascending/descending the stairs, raising arms), more allowances were given to the measurements (i.e. body rise + 2cm and crotch depth + 1cm for squatting down pose; thigh circumference + 1cm and knee circumference + 1cm for ascending/ descending the stairs pose; chest circumference + 5~6cm and jumper length to the level of hip circumference line for raising arms pose) for work clothes patternmaking. The evaluation of the two types of spring/summer and winter work clothes' clothing comfort and wearer mobility suggested certain points to improve the clothing performance (e.g. ventilation slits on the back pleats, arm pits and collar band of the spring/summer suit using net material and lining for the winter suit using quilted thermal materials) and wearer mobility (e.g. pants hem buckles for the easy work motion), which also enabled to fulfill the workers' work clothes design preference.

• Journal of Fashion Business
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• v.15 no.2
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• pp.145-159
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• 2011

The study aimed to analyze the status quo of manufacturing work environment and the work clothes' clothing comfort and wearer mobility of welding and grinding work processes in the machine and shipbuilding industries in South Korea. A questionnaire survey was conducted for the study, which consisted of questions about work clothes' clothing comfort and wearer mobility according to body parts. The findings derived from the research were: the high impact levels of work environment factors on welding and grinding work processes were noise, metal fragment, superheat, toxic gas, UV ray factors. Subject workers' assessment of work clothes' clothing pressures were in the levels between 3 (i.e. moderate) and 4 (i.e. comfortable) in a range of 5-point scale. The impact levels of wearer mobility factor were high on the work processes of welding and grinding in machine and grinding in shipbuilding. While welding process in shipbuilding showed a 'moderate' wearer mobility level and this was because its work postures were uncomfortable yet the rate of the motion change was low. The consideration to develop the work clothes specialized for certain work processes should include the materials' protecting performance from the hazardous work environment factors; and work clothes' designs that provides workers with maximized clothing comfort and wearer mobility for bending or tilting postures of upper, lower and lateral body parts defined in the study.

• Fashion & Textile Research Journal
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• v.26 no.1
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• pp.123-136
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• 2024

This study aimed to assess the mobility and thermal comfort of personal protective equipment (PPE) among female healthcare workers, taking into account wearers' physique and PPE protection levels. A total of 16 participants (age: 26.3 ± 8.3 y, height: 161.5 ± 7.3 cm, body weight: 57.1 ± 11.0 kg, BMI: 21.9 ± 3.6), representing diverse body types, underwent four PPE conditions: L (Low_Plastic gown ensemble), M (Medium_Tyvek 400), H (High_Tyvek 800J with Powered Air Purifying Respirator [PAPR]), and E (Extremely high_Tychem 2000 with PAPR, Bib apron, and Chemical-resistant gloves). The mobility protocol consisted of 10 different tasks in addition to donning and doffing. The 10 tasks were repeated twice at an air temperature of 24.3 ± 0.1℃, 59±4%RH. Findings revealed a disproportionate relationship between PPE protection and wearer discomfort. Significant differences in clothing microclimate and total sweat rate were observed between the lowest (L) and highest (E) protection levels (p < 0.01), while distinctions among medium levels were inconclusive. Subjective evaluations favored conditions H and L over M and E (p < 0.05), indicating reduced heat, and humidity, increased comfort, and lower exertion. Instances of mobility discomfort, specially in the small body type group, underscored the need for a suitable PPE size system for Korean adult female medical workers. Furthermore, enhancements in gloves, shoe cover, and PAPR hood designs are essential for improving ease of movement and preventing hindrance.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.1002-1005
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• 2002

We have synthesized novel stilbenequinone derivatives(ASQ, PSQ) and investigated the properties of their electron drift mobility. Characteristics of the ionization potential Ip and electron affinity Ea of the ASQ were investigated by determining both oxidation and reduction potentials. There were estimated Ip = 7.1 eV and Ea = 3.6 eV. The electron drift mobility of ASQ mixture(R:t-Bu 10wt%) was $1.5{\times}10^{-5}cm^2/V{\cdot}sec$ at $6.15{\times}10^{5}V/cm$ and $1.3{\mu}m$ thickness.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.994-997
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• 2002

We have synthesized novel Diphenoquinone(DQ) derivatives. Electron drift mobility of DQ series was measured and electron affinity$(E_a)$ of them is estimated 3.7~3.9eV by CV. Electron drift mobility$(\mu)$ of electric field dependence by time of flight(TOF) technique is $1.76{\times}10^{-5}cm^2/V{\cdot}s$(DQ5) at the concentration of 10wt% verse poly(4,4'-cyclohexylidene diphenylcarbonate)(Pc-Z) and $1.66{\times}10^6V/cm$.

• International Commerce and Information Review
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• v.9 no.2
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• pp.87-101
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• 2007

This study developed seven assumptions to demonstrate the effect of personal innovation, social influences, service quality, mobility and accessibility on perceived usability, perceived convenience use and use intention using a technology acceptance model developed by Davis(1989), and the results are presented as follows: First, the assumption that personal innovation and service quality of mobile banking service will influence the perceived usability was adopted while the assumption that social influences will affect the perceived usability was rejected. Second, the assumption that mobility and accessibility of mobile banking services will influence the perceived convenient use was selected. Third, the assumption that the perceived usability of mobile banking service will influence use intention was rejected while the assumption that the convenient use will influence use intention was adopted. This study suggests that as personal innovation, service quality, mobility and accessibility have a significant influence on use of mobile banking, service providers should pay more attention to development of security programs and diversification of contents.