• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
• /
• pp.370.1-370.1
• /
• 2014

Giant magnetoresistance (GMR), tunneling magnetoresistance (TMR), and magnetic random-access memory (MRAM) are currently active areas of research. Magnetite, Fe3O4, is predicted to possess as half-metallic nature, ~100% spin polarization (P), and has a high Curie temperature (TC~850 K). On the other hand, Spinel ferrite CoFe2O4 has been widely studies for various applications such as magnetorestrictive sensors, microwave devices, biomolecular drug delivery, and electronic devices, due to its large magnetocrystalline anisotropy, chemical stability, and unique nonlinear spin-wave properties. Here we have investigated the magneto-transport properties of epitaxial CoxFe3-xO4 thin films. The epitaxial CoxFe3-xO4 (x=0; 0.4; 0.6; 1) thin films were successfully grown on MgO (100) substrate by molecular beam epitaxy (MBE). The quality of the films during growth was monitored by reflection high electron energy diffraction (RHEED). From temperature dependent resistivity measurement, we observed that the Werwey transition (1st order metal-insulator transition) temperature increased with increasing x and the resistivity of film also increased with the increasing x up to $1.6{\Omega}-cm$ for x=1. The magnetoresistance (MR) was measured with magnetic field applied perpendicular to film. A negative transverse MR was disappeared with x=0.6 and 1. Anomalous Hall data will be discussed.

• 한국의류학회지
• /
• 제29권6호
• /
• pp.847-858
• /
• 2005

The purpose of this study was to examine consumer purchasing behavior of the online shoppers particularly using online clothing shopping mall and to analyze the key factors of both satisfaction and dissatisfaction of their purchase and to compare the both group by lifestyle segmentation in order to provide the e-CRM strategies. Focus group interviews and survey were conducted in December, 2003 with 30 online shoppers who have an experience of online clothing purchasing. The data analysis included the content analysis, descriptive statistics, K-means and factor analysis. Key findings of the study were as follows: First, online shoppers spent average 3.5 hours on internet and usually purchased clothing while surfing the web. Second, consumers were satisfied with reasonable price and customized service but dissatisfied with delayed delivery, limited product availability in both size and color and return policy. Third, according to the lifestyle segmentation, online shoppers could be characterized as 'Luxurious', 'Trendy' and 'Prudent' 'Luxury-oriented consumers', who value fashion, diet and social activity, tended to purchase basic yet high quality products. However, 'Trend-oriented consumers', to whom fashion trend was most important, purchased various latest fashion products with reasonable price and showed generally positive response to emails sent by e-retailers. And lastly 'Prudence-oriented consumers', whose buying decision was based solely on practicality, appeared to be reluctant to purchase clothing online while seeking more credible information and competitive price. In conclusion, this study has its significance in that it helps promote relationships between customers and e-retailers by providing differentiated e-CRM strategies through each customer groups 'lifestyle segmentation and consumer purchasing behavior analysis.

• 센서학회지
• /
• 제24권1호
• /
• pp.22-28
• /
• 2015

This study demonstrates a polyimide nerve cuff electrode with a conductive polymer for improving recording signal quality at peripheral nerve. The nerve cuff electrodes with platinum (Pt), iridium oxide (IrOx), and poly(3,4-ethylenedioxythiophene): p-toluene sulfonate (PEDOT:pTS) were fabricated and investigated their electrical characteristics for improving recorded nerve signal quality. The fabricated nerve cuff electrodes with Pt, IrOx, and PEDOT:pTS were characterized their impedance and CDC by using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry. The impedance of PEDOT:pTS measured at 1 kHz was $257{\Omega}$, which was extremely lower than the value of the nerve cuff electrodes with IrOx ($15897{\Omega}$) and Pt ($952{\Omega}$), respectively. Furthermore, the charge delivery capacity (CDC) of the nerve cuff electrode with PEDOT:pTS was dramatically increased to 62 times than the nerve cuff electrode with IrOx. In ex-vivo test using extracted sciatic nerve of spaque-dawley rat (SD rat), the PEDOT:pTS group exhibited higher signal-to-interference ratio than IrOx group. These results indicated that the nerve cuff electrode with PEDOT:pTS is promising for effective implantable nerve signal recording.

• 산업공학
• /
• 제16권spc호
• /
• pp.99-104
• /
• 2003

While demands for express service are rapidly increasing according to recent progress of electronic commerce, express service companies are struggling to take a larger delivery service market share through ongoing improvement in their service processes. Extension of cut-off time for express service centers can provide the express company with increase of total sales, but it may also cause to increase the possibility not to satisfy customer needs due to work delay in the consolidation terminal. Therefore, compromised decision for cut-off time of each service center should be made by taking operation characteristics of the consolidation terminal into account. This study suggests an approach for determining the cut-off time for express service centers according to operational characteristics of the consolidation terminal with the objective of maximizing expected incremental sales. The problem defined in this study can be represented as two successive models; one is an integer programing model in which the best cut-off time for each sales center are determined, and the other is a single machine scheduling model in which a working schedule in the consolidation terminal is obtained. A genetic algorithm is developed to solve the two models simultaneously. Finally, an example problem is carried out to verify applicability and performance of the algorithm with the data set collected from an express company.

• 대한안전경영과학회지
• /
• 제12권2호
• /
• pp.183-192
• /
• 2010

Korean logistics industry have been focused on transportation business. However, with the expansion of the electronic commerce and on-line shopping, delivery service is now dramatically growing. Despite the expansion of logistics market, the domestic logistics industry have significant structural problems such as low productivity comparing with the advanced countries, relatively high cost and shortage of human resources and lack of professionalism of people in the industry. Logistics companies reallocate employees, use subcontractors, expand consignment and training the employees to overcome the labor shortages but it has some limits. In recognition of the importance of labor in the logistics industry, financial support and investment have increased. Logistics companies tend to hire consultants, set up logistics department or R&D center in order to establish highly productive logistics process and system so it is viewed that there will be considerable demands of human resources in the logistics industry. This study indicates implications and development direction of human resources in the logistics industry by looking into prospect and characteristic of the industry, employment status, training programs and qualification requirements.

• 한국정보시스템학회지:정보시스템연구
• /
• 제21권4호
• /
• pp.155-183
• /
• 2012

Means-Ends Network model was used to identify factors of means objective(means supplied by vendor) and fundamental objectives(purchasing motivations) for purchasing decision-making structure and dimensions of customer values on purchasers of internet shopping mall in Korea and China. In Means-Ends Network 6 factors(shopping travel, shipping assurance, vendor trust, online payment, product choice, and recommender systems) were found as a means objectives and 3 factors(shopping convenience, internet environment, customer support) as a fundamental objectives of shopping. However the results of hypotheses test for Means-Ends Network show some important differences between two countries. Something important to notice here is that Chinese customers shopping in China recognize shipping assurance factor and vendor trust factor as important factors satisfying all fundamental objectives unlike as in the case of our country. As these two factors are attribution factors responsible to the sellers, it is identified that customers do not trust the sellers and sellers have not met the expectations of customers. Therefore, these results show that the seller efforts assuring the reliability of the seller themselves, such as conducting its own compensation scheme are more important rather than the establishment of the guarantee institution to guarantee reliability and delivery assurance of sellers and implementation of legal and institutional apparatus such as the settlement of e-commerce licence system. Though this study presents such an important marketing implications, it can be pointed out that the limits are this research was done on the general Internet shopping malls without considering the Internet shopping mall types of diversity, the survey was designed around the student samples for convenience of the investigation because it was an international survey and the collected data has been limited to the western coast cities, such as China's Beijing, Shanghai, and Dalian.

• 한국전자거래학회:학술대회논문집
• /
• 한국전자거래학회 1999년도 학술대회지 vol.1
• /
• pp.277-299
• /
• 1999

Since Chrysler Motor Co. had experienced the digital development system in the beginning of 1990's, most of leading automobile companies are trying to apply a digital information system for their own business process reengineering based upon concurrent engineering system from product planning phase. This is called as virtual DMU(Digital Mock-Up) system instead of the traditional PMU(Physical Mock-Up) system. By using the virtual prototype, all of the design requirements and system specifications can be checked, changed and optimized more quickly and more efficiently. This paper consists of five chapters for the DMU information system. In the 1$^{st}$ chapter, the principle of digital design system is suggested by using four basic modules such as product design module, process design module, manufacturing system design module and central control module. The basic scheme of DMU is introduced with the benefits of application in the chapter 2. In the chapter 3, a digital design process of new car development is explained with the detailed DMU design and design review processes. In the chapter 4, the practical DMU manufacturing techniques and applications are introduced as CAD/CAM analyses, DPA(Digital Pre-Assembly)reviews for development, production, operation and maintenance phases, digital tolerance analyses and digital factory analyses for assembling line simulation, automated robot welding processes, production jig ＆ fixtures and painting process simulation. Finally, the activities of digital design support; CAS-styling, CAE-engineering and CAT-testing are summarized for design optimization in the chapter 5. As today's automobile manufactures and related business organizations are struggling to compete in the global marketplace, they are concentrating on efficient use of DMU information system to reduce the new car development cost, to have shorten the delivery schedule and to improve product design quality. To meet the demand of those automobile industries on digital information systems, the CALS(Computer aided Acquisition and Logistics Support) and EC(Electronic Commerce)initiative has been focused as a dominant philosophy in defense ＆ commercial industries, specially automobile industries.s.

• 한국정보통신학회논문지
• /
• 제22권7호
• /
• pp.1030-1040
• /
• 2018

분산 이동성 관리 방식은 이동성 기능을 사용자와 가까이에 위치한 네트워크 경계로 분산시킨다. 이에 따라서 트래픽 전달 비용을 낮추고 패킷 전달 경로를 최적화할 수 있으며 확장성이 높은 장점을 갖는다. 하지만, 시그널링 메시지를 교환하기 위한 모바일 앵커의 개수가 증가하여 시그널링 비용이 증가하는 문제점을 갖는다. 그래서 지속시간이긴 세션에 대해서 높은 시그널링 비용을 감소시키는 하이브리드 분산 이동성 방식이 연구되었고 본 논문에서는 네트워크 이동성을 지원하는 환경으로 하이브리드 방식을 확장한다. 모바일 라우터는 차량에 장착되어 모바일 장치들과 함께 이동한다. 따라서 모바일 라우터에 대해서 고속 이동성 특성을 정의하여 이용하는 하이브리드 방식을 제안한다. 모바일 라우터의 이동성 특성에 따라서 모바일 앵커를 분산하여 할당하거나 혹은 특정한 모바일 앵커를 지정하여 할당한다. 본 논문은 네트워크 이동성을 지원하는 하이브리드 분산 이동성 관리 방식에 대해서 제안하고 성능을 수학적으로 분석하여 우수한 성능임을 보여준다.

• Journal of Korean Biological Nursing Science
• /
• 제21권2호
• /
• pp.114-122
• /
• 2019

Purpose: The purpose of the study was to examine the relationship between smoking attitude and coping skills toward secondhand e-cigarette smoking among nonsmoking college students. Methods: This study was conducted with 148 students from a University in Seoul, Korea. Participants completed questionnaires and the data were analyzed using a T-test, ANOVA, and Pearson's correlation coefficients. Results: The mean score of smoking attitude is $51.35{\pm}4.73$. The mean score of coping skills is $13.89{\pm}2.53$ in verbal skills, $10.16{\pm}2.37$ in behavioral skills, and $8.32{\pm}2.30$ in assertive skills. Coping skills toward secondhand smoking are noted as being different by current cohabitation smoker. A significant relationship between smoking attitude and behavioral coping skills(r = .23, p= .004) was found, which means that a better smoking attitude was correlated with more active behavioral coping skills. Conclusion: The results showed that nonsmoking college students with better smoking attitude react to the E-cigarette smoking with more active behaviors. Therefore, interventions are needed to be developed to encourage better smoking attitude and coping skills toward secondhand E-cigarette smoking.

• 한국정보통신학회논문지
• /
• 제25권5호
• /
• pp.691-700
• /
• 2021

IP 카메라는 원격지에서도 감시할 수 있을 뿐만 아니라, UTP를 통해 전원 공급도 가능한 장점을 가지고 있으므로 아날로그 CCTV를 급속하게 대체하고 있다. 본 논문에서는 IP 카메라에 널리 적용되고 있는 ONVIF 표준의 프로토콜 구조와 그 외에도 이를 지원하기 위한 인터넷 프로토콜들을 소개하고, 상용보드 상에서 ONVIF 디바이스를 구현한다. 이러한 기능들은 클라이언트 (PC)의 관리 프로그램에서 제어 가능하지만, 사생활 보호 마스크나 열화상 카메라의 온도표시, 관심 영역과 같은 기능은 디바이스 상에서 웹 뷰어를 통해 구현한다. 실험을 통해 IP 카메라와 클라이언트 프로그램이 주고받는 SOAP 메시지와 스트리밍되는 영상을 통해 ONVIF Profile S와 웹 뷰어 기능을 확인한다.