• Title/Summary/Keyword: Distribution & Service

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A study on the imputation solution for missing speed data on UTIS by using adaptive k-NN algorithm (적응형 k-NN 기법을 이용한 UTIS 속도정보 결측값 보정처리에 관한 연구)

  • Kim, Eun-Jeong;Bae, Gwang-Soo;Ahn, Gye-Hyeong;Ki, Yong-Kul;Ahn, Yong-Ju
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.13 no.3
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    • pp.66-77
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    • 2014
  • UTIS(Urban Traffic Information System) directly collects link travel time in urban area by using probe vehicles. Therefore it can estimate more accurate link travel speed compared to other traffic detection systems. However, UTIS includes some missing data caused by the lack of probe vehicles and RSEs on road network, system failures, and other factors. In this study, we suggest a new model, based on k-NN algorithm, for imputing missing data to provide more accurate travel time information. New imputation model is an adaptive k-NN which can flexibly adjust the number of nearest neighbors(NN) depending on the distribution of candidate objects. The evaluation result indicates that the new model successfully imputed missing speed data and significantly reduced the imputation error as compared with other models(ARIMA and etc). We have a plan to use the new imputation model improving traffic information service by applying UTIS Central Traffic Information Center.

Distributed Binding Update Scheme for Fast Handoff in Non-Nested Network Mobility Environment (비 중첩 네트워크 이동성 환경에서 빠른 핸드오프를 위한 분산 바인딩 갱신 기법)

  • Kim, Hoon;Song, Ui-Sung
    • The Journal of Korean Association of Computer Education
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    • v.10 no.5
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    • pp.81-88
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    • 2007
  • To support the movement of a mobile network consisting of several mobile nodes, the IETF NEMO working group proposed NEMO basic support protocol using bi-directional tunneling between the home agent and the mobile router. Since NEMO basic support protocol is based on bi-directional tunneling, all communications to and from mobile nodes are suffer from inefficient routing all the cases. To solve the routing inefficiency problem, several proposals are proposed. However, those proposals results in new problems, such as binding update storm and changes in existing protocol. Especially, binding update storm problem may cause the delay in binding update, this subsequently causes the difficulty for a real time service and the handoff delay on the movement of mobile network. In this paper, we propose a new binding update scheme which reduces binding update latency and the handoff delay through the distribution of the transmission time of binding update messages. The performance of the proposed scheme is also evaluated to demonstrate its efficiency. Simulation results show that the proposed scheme can efficiently reduce the binding update latency.

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Analysis on the Navigational Dangerous Elements in Southwestern Coastal Area of Korea (서남해 연안해역의 항행 위해요소에 관한 분석)

  • Baek, Won-Sun;Gim, Ok-Sok;Jeong, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.3
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    • pp.219-225
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    • 2008
  • Since July 2006, marine traffic safety management system have been enforced to support the vessels transiting across the coastal area and the vessels coming in and out of ports in southwestern coastal area where heavy traffic density and marine casualties occurred frequently. The marine traffic volume for the marine traffic environmental assessment was measured by the information from RADAR and AIS system in the area. The distributions of marine casualties were analyzed in the main routes and traffic separation schemes during the last five years and the navigational dangerous elements were investigated with the influence of natural environment, the distribution of fisheries and survey questionnaire. Marine accidents of merchant ships have a tendency to decrease gradually but in case of fishing boats, the rate of marine accidents have a contrary results in this area during the last five years. The dangerous elements on navigation appeared to be the dense force from June to August, fisheries activities and the vessels which not follow the compulsory watch on VHF-band radio communication equipments.

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Improvement of Emulsion Stability of Food Proteins by Microbial Transglutaminase (미생물유래 transglutaminase를 이용한 식품단백질의 유화안정성 향상에 관한 연구)

  • Lee, Deuk-Sik
    • Korean Journal of Food Science and Technology
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    • v.37 no.2
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    • pp.164-170
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    • 2005
  • To improve functional properties of food proteins, homologous or heterologous ${\beta}-casein$ and 11S globulin(glycinin) from animal and vegetable proteins, respectively, were bio-hybridized using transglutaminase(MTGase). Susceptibility was confirmed by SDS-PAGE, particle size analyzed, and emulsion stability tested using Reddy and Fogler method, To determine how bio-hybridized protein influences emulsion stability, protein bound on oil droplet was investigated using Scanning Electron Microscopy (SEM). formation of bio-hybridized protein band was detected among homologous and heterologous proteins, with heterologous protein forming weak band in oligomer form. Homologous ${\beta}-casein$ protein showed high emulsion stability, while homologous glycinin showed almost no stability. Stability of heterologous ${\beta}-casein$ and glycinin protein was higher than that of glycinin. SEM photographs showed even distribution of bio-hybridized proteins on oil droplet improved stability.

Suggestion on Chinese Clothing Market Launching : Focused on Foreign Students's Clothing Buying Behavior in Korea

  • Koo, In-Sook;Liu, Dashuang
    • Journal of Fashion Business
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    • v.15 no.6
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    • pp.1-22
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    • 2011
  • This paper is a study on the information required for developing Korean clothing products intended for Chinese students in Korea and for opening markets of Korean clothing and brands in China. It analyses the buying behaviors, purchasing ability, the favourite apparel type for clothing, and satisfaction with Korean clothing and brands of Chinese students in Korea, with which it seeks a program for South Korea branding to enter into the Chinese clothing market. Three hundred fifty seven students of Hannam University and PaiChai University Chung nam National University in Daejeon-city took part in this study. This paper adopts Descriptive Analysis, Crossing Analysis, Bivariate Correlations, and One-way ANOVA in SPSS 17.0 with Post Hoc Multiple Comparisons to know about the impact of demographic variables of Chinese students in Korea on buying information sources, the criteria for store selection, buying capacity, praise degree on various properties of Korean clothes products and their satisfaction with Korean clothes products. The first proposal of expanding China market for Korean merchants is to achieve maximum sales based on sales promotion strategies, such as the credit card corporations, the store display and sales person service development, SPA, design size development, and to upgrade consumption values. The second proposal is Korean clothes corporations should open the Internet shopping corresponding to the physical stores, the most frequently used information source of Chinese students is the network, from the age distribution of Internet users in 2008 in China, population above 10 and below 30 accounts for 66.7% of all users, In recommending clothes made in Korea to Chinese young people, on-line advertising will get better effects than other strategies, specially during advertisement, they should take good use of Korean television shows and variety shows or help Chinese poor areas to do the social contribution hereby to improve the public image of Korean clothes corporations, which can bring good sale promotion effects as well.

A Study of the Employee's Attitude Toward Operation of the Hospital Material Requirements Planning System(HMRPS) in University Hospitals (병원 종합 물류시스템 운영에 대한 관련직원들의 인식)

  • Lee, Kwang-Yong;Yu, Seung-Hum;Sohn, Tae-Yong
    • Korea Journal of Hospital Management
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    • v.4 no.2
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    • pp.266-285
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    • 1999
  • The purpose of this study is to identify influencing factors for successful introduction, implementation and management of HMRPS through assessment of the employees attitude toward HMRPS in technical, administrative, and organization behavioral areas. Data were collected from 157 HMRPS employee members' self-reporting questionnaire in three university hospitals in the city of Seoul and Kyonggi Province from November 5 to November 10, 1997. Relevant literature on industry company MPR system theory was reviewed to develop the theoretical framework. The results were as follows: The employee's recognition of tangible benefit were more significantly influenced success than intangible benefit for successful operation relating the HMRPS. Concerning the employee's recognition of the successful HMRPS and the factor of influenced success was significantly positive correlation between tangible and intangible benefits and success factor in technical, administrative, and organizational behavior area. This study showed that major factor affecting the employee's recognition of tangible and intangible benefit for successful HMRPS. For tangible benefits; Success factors in the technical areas were quality of the data and information, efficiency of inventory management and rescheduling of operation plan. Success factors in the administrative areas were: role of top management. Success factors in the organization behavioral areas were; simplicity of the HMRPS, human resistance to change. For intangible benefits; Success factors in the organization behavioral areas were; user involvement, simplicity of HMRPS, human resistance to change. Futhermore as the exact evaluation of successful factors of HMRPS implement is needed, research for the development of systemic variables of physical distribution system control, methods, capacity of system, duration and other environment in many of 30 hospitals or more, and for the empirical study for HMRPS.

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Analyzing the Relationships between Changes in Postpartum Depression and Child-rearing System Variables in Korean Mothers (한국 영아어머니의 산후우울 변화와 양육 관련 체계변인간의 관계 분석)

  • Chun, Hui-Young;Ok, Kyung-Hee
    • Journal of Families and Better Life
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    • v.29 no.6
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    • pp.153-167
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    • 2011
  • This study analyzed changes in postpartum depression in mothers from one month after childbirth to the first year using panel data collected overtime, in an effort to determine the relationship between the amount of change and child-rearing system variables. The subjects were 1097 mothers who belonged to both the lower and upper $30^{th}$ percentile groups in the depression change distribution of the 2008 Korean Children Panel Study (PSKC), a large, population-based study conducted by the Korea Institute of Childcare and Education. The data were analyzed by t-tests, $x^2$ tests, partial correlation coefficient analyses and regression analyses. The results are summarized as follows: First, the mothers' postpartum depression showed a significant increase during the first year as opposed to the first month after birth. Second, after controlling for socio-demographical variables of the mothers, the changes related to depression showed a positive relationship with child-rearing stress, and the child's emotional temperament, but showed a negative relationship with the mother's self-esteem, the child's birth order, and the father's participation in child-rearing activities. Third, variables having a significant effect on changes in postpartum depression were the mother's self-esteem and child-rearing stress, the child's age in months, and social support. Variables pertaining to the mother's characteristics variables had a more powerful effect than other child-rearing system variable categories. The results suggest the necessity to develop a parental education program or a mother-child health service in consideration of the variables that affect mothers, as determined in this study, in an effort to prevent postpartum depression.

The Convergence Effect of Gender, Age, Motivation, Sensitivity and Information Acceptance of Aviation Related Social Media Users (항공 관련 소셜미디어 이용자의 성별, 연령, 이용 동기, 민감도와 정보수용의 융합적 영향 연구)

  • Hong, Ji-Suk
    • Journal of the Korea Convergence Society
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    • v.11 no.3
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    • pp.201-210
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    • 2020
  • The study was conducted to predict usage attitudes and behaviors by combining usage motivation and sensitivity, gender, and age in aviation-related social media. Specifically, the purpose of this study was to examine the effects of social media information acceptance, motivation and sensitivity on gender acceptance by gender and age. To this end, we collected data in an even distribution to prevent gender and age bias among adults aged 20 or older online from April 19 to May 3, 2018. As a result, the lower the female and age in the gender and age had a positive effect on the acceptance of social media information. Motivation for use has a positive effect on information acceptance and sensitivity has a negative effect on information acceptance. Through this, it was found that user class such as gender and age, motivation to use, and sensitivity affect information acceptance. In addition, the negative aspects of the sensitivity factor can be identified, and it is expected to be used as basic data in aviation-related social media marketing strategies.

A Study on Fashion Product Purchasing Behavior in Social Commerce (소셜커머스에서 패션제품 구매행동에 관한 연구)

  • Ju, ChanHee;Rhee, YoungJu
    • Journal of the Korea Fashion and Costume Design Association
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    • v.16 no.4
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    • pp.1-14
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    • 2014
  • In social commerce, consumers can buy products at much cheaper price if the required minimum number of buyers are made. Social commerce has showed rapid growth as an innovative distribution system receiving highlights, however it is true that it hasn't been sufficiently studied. The purpose of the study for presents the direction of growth of the fashion industry with social commerce through qualitative studies. This study is to make a preference group of four people and a non-preference group of four people of social commerce users for the fashion items sold social commerce market and lastly proposes some improvements. The 'preference group' showed high familiarity and preference to social commerce; and they had the tendency of the pursuit of convenience and voluptuous shopping. The revisit of 'non-preference group' preferred open market and, had the tendency of economical shopping and, they are favorable to other categories of social commerce. The reasons of preference were that accessibility was good in fashion products purchasing behaviors in social commerce and, it was convenient and, price was good and new information on cheap and good products were provided; the reasons of non-preference were that the quality of the products and genuineness of articles are doubtful or, the price is not the lowest or, the carried over products were majority. In the perspective of the fashion products in social commerce they answered that it would be brighter but improvements are needed such as supplying exact information, the lowest price, diversified products and the subdivision of category.

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Measurement and Comparison of Wi-Fi and Super Wi-Fi Indoor Propagation Characteristics in a Multi-Floored Building

  • Hwang, Gyumin;Shin, Kyubo;Park, Sanghyeok;Kim, Hyoil
    • Journal of Communications and Networks
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    • v.18 no.3
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    • pp.476-483
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    • 2016
  • Super Wi-Fi is a Wi-Fi-like service exploiting TV white space (WS) which is expected to achieve larger coverage than today's Wi-Fi thanks to its superior propagation characteristics. Super Wi-Fi has been materialized as an international standard, IEEE 802.11af, targeting indoor and outdoor applications, and is undergoing worldwide field tests. This paper demonstrates the true potential of indoor Super Wi-Fi, by experimentally comparing the signal propagation characteristics of Super Wi-Fi and Wi-Fi in the same indoor environment. Specifically, we measured the wall and floor attenuation factors and the path-loss distribution at 770MHz, 2.401 GHz, and 5.540 GHz, and predicted the downlink capacity of Wi-Fi and Super Wi-Fi. The experimental results have revealed that TVWS signals can penetrate up to two floors above and below, whereas Wi-Fi signals experience significant path loss even through a single floor. It has been also shown that Super Wi-Fi mitigates shaded regions of Wi-Fi by providing almost-homogeneous data rates within its coverage, performs comparable to Wi-Fi utilizing less bandwidth, and always achieves better spectral efficiency than Wi-Fi. The observed phenomena imply that Super Wi-Fi is suitable for indoor applications and has the potential of extending horizontal and vertical coverage of today's Wi-Fi.