• 센서학회지
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• 제16권4호
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• pp.277-285
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• 2007

In this paper, we outline the research issues that we are pursuing towards building of location aware environments for mainly ubiquitous healthcare applications. Such location aware application can provide what is happening in this space. To locate an object, such as patient or elderly person, the active ceiling-mounted reference beacons were placed throughout the building. Reference beacons periodically publish location information on RF and ultrasonic signals to allow application running on mobile or static nodes to study and determine their physical location. Once object-carried passive listener receives the information, it subsequently determines it's location from reference beacons. The cost of the system was reduced while the accuracy in our experiments was fairly good and fine grained between 7 and 12 cm for location awareness in indoor environments by using only the sensor nodes and wireless sensor network technology. Passive architecture used here provides the security of the user privacy while at the server the privacy was secured by providing the authentication using Geopriv approach. This information from sensor nodes is further forwarded to base station where further computation is performed to determine the current position of object.

• 경영과학
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• 제10권2호
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• pp.79-91
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• 1993

Strategic decisions related to the design of a physical distribution system can be classified into three basic components : facility location, transportation, inventory decisions. In this research the interdependence of those decisions are expressed in a mathematical model such that the total relevant cost of the system is minimized. We suggested a heuristic technique for solving the model. In broad terms, our solution technique combines a heuristic method for determining which candidate DCs to open and an exact method for minimizing costs given a set of open DCs. And we also developed a decision supporting package for the design of a physical distribution system.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.348-351
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• 2016

최근 IoT 환경에서 많은 디바이스들의 등장과 더불어 특정 사용자만 접근 가능한 보호된 네트워크가 필요하게 되었다. IoT 네트워크 환경에 OAuth 프로토콜을 적용하여 인증하게 되면 보다 쉽게 네트워크 인증 체계를 구축할 수 있으나 OAuth는 공격자가 Token을 가로채게 되면 쉽게 공격에 노출되는 단점이 있어 2차 인증이 필수적이라고 할 수 있다. 궁극적인 IoT는 Fog Computing이 필수적이다. Fog Computing은 Cloud를 확장시켜 network Core에서 뿐만 아니라 Edge에서도 Computing이 가능하게 하고, node간의 통신을 가능하게 하는 플랫폼이다. Fog Computing의 장점으로는 Location awareness나 Support for mobility 등을 들 수 있다. Fog Computing내에서 사용할 인증이 이런 Fog Computing의 장점을 살린다면, 더 IoT에 걸맞은 인증을 할 수 있을 것이다. 이에 2차 인증에 기존의 인증서나 id/password, 또는 group key같은 번거로운 것을 이용하지 않고 Cyber-Physical-Social System을 사용한다면 user의 편리성을 더 증가시킬 수 있을 것이다. 본 연구에서는 Cyber-Physical-Social System기반의 인증에 관한 연구를 진행하려 한다.

• 한국전문물리치료학회지
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• 제18권4호
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• pp.60-67
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• 2011

Ultrasonography (US) is a recent technique that has proven to be useful for assessing muscle thickness and guiding the rehabilitation decision-making of clinicians and researchers. The purpose of this study was to determine the inter-rater reliability of the US measurement of transversus abdominis (TrA), internal oblique (IO), and external oblique (EO) thicknesses for different probe locations and measurement techniques. Twenty healthy volunteers were recruited in this study. Muscle thicknesses of the transversus TrA, IO, and EO were measured three times in the hook-lying position. The three different probe locations were as follows: 1) Probe location 1 (PL1) was below the rib cage in direct vertical alignment with the anterior superior iliac spine (ASIS). 2) Probe location 2 (PL2) was halfway between the ASIS and the ribcage along the mid-axillary line. 3) Probe location 3 (PL3) was halfway between the iliac crest and the inferior angle of the rib cage, with adjustment to ensure the medial edge of the TrA. The two different techniques of thickness measurement from the captured images were as follows: 1) Muscle thickness was measured in the middle of the muscle belly, which was centered within the captured image (technique A; TA). 2) Muscle thickness was measured along a horizontal reference line located 2 cm apart from the medial edge of the TrA in the captured image (technique B; TB). The intraclass correlation coefficient (ICC [3,k]) was used to calculate the inter-rater reliability of the thickness measurement of TrA, IO and EO using the values from both the first and second examiner. In all three muscles, moderate to excellent reliability was found for all conditions (probe locations and measurement techniques) (ICC=.70~.97). In the PL1-TA condition, inter-rater reliability in the three muscle thicknesses was good to excellent (ICC=.85~.96). The reliability of all measurement conditions was excellent in IO (ICC=.95~.97). Therefore, the findings of this study suggest that TA can be applied to PL1 by clinicians and researchers in order to measure the thickness of abdominal muscles.

• 농촌계획
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• 제27권3호
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• pp.93-102
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• 2021

This study was attempted to provide a scientific basis for the problem of location selection by spatial scale for efficient promotion of projects related to green care farm complex. Location potential assessment system in local government scale consists of two major components from demand-side and supply-side consideration. The demand-side aspect considered the characteristics of potential users, while supply-side aspect used total 18 indices over 8 divisions under 3 fields. For the location potential assessment in district scale, total 8 indices under 3 major divisions were considered based on biological, physical, social, and economic environment. The application results of the location potential evaluation system in local government scale(excluding metropolitan cities) showed high location potential in southern Gyeonggi Province and near Busan Metropolitan City. As a result of applying the district-scale location potential evaluation system to Geumsan-gun, Geumsan-eup, Chubu-myeon, and Jewon-myeon have high potential. Further studies to improve the applicability of the developed indices are recommended by enhancing assessment indices, complementing base data, and reinforcing with spatial analysis.

• 한국조경학회지
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• 제28권3호
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• pp.88-96
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• 2000

The objective of this study is to evaluate the preference and visual characteristic of users according to the location of benches at urban community parks. The types of benches are separated into four patterns and located in four representative places at urban community parks. Each relations between visual preference and adjective related factors are calibrated by the estimated results of Pearson correlation coefficient. Moreover, the factors which affect the visual preference are obtained by multiple regression analysis and to calibrate the each factors significant level, the method of multivariate variance analysis is applied. The results of this study are summzrized as belows: 1. Four types of factors which consist the visual characteristic are classified as emotional factor of visual images(aesthetic factor(F1), texture related factor(F2)) and physical factor(physical factor(F3), transformable factor(F4)). Each factor's eigenvalue is appears as 5.27∼1.78 and the eigenvalue of emotional factor of visual images is more higher than the physical factor. 2. The correlation coefficient between visual preference according to the location of benches(X21) and aesthetic factor(f1) is estimated as 0.79, which is highest value among the four factors. And the correlation coefficient of texture related factor(f2), physical factor(F3) and transformable factor(F4) is estimated as 0.14, 0.04 and 0.08 respectively. 3. The visual preference of users according to the location of benches is greatly affected by the emotional factor of visual images(F1, F2) and the physical factor(F3, F4) are poorly related. The results of this study suggest the effective guidelines for the location of leisure facilities. Moreover the design and planning of leisure facilities at the urban community park have to be reexamined. What must be examined from now on is as follows: First, the preference research of rest facilities in the urban park through the multiple approach must be carried out continuously. Second, the research about the visual quality of the environmental sight observed in sitting on the bench as well as the visual quality of the showed object and place needs to be supported. Nevertheless, through this study the utilization into the useful data of the plan and the design for the systematic disposition of landscape architecture equipments centered on the users can be expected.

• 정보처리학회논문지C
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• 제13C권5호
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• pp.595-600
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• 2006

오늘날 저가의 RFID 기술은 리더와 태그사이에 물리적인 접촉 없이 인식 가능한 기술로서 기업과 학술적 분야에서 많은 각광을 받고 있다. 그러나 태그의 정보가 전송과정에 무선특성에 따른 과도한 정보 노출과 사용자의 위치정보 추적과 같은 심각한 프라이버시 침해를 유발시킨다. 특히 읽기전용 태그에서의 보안문제는 단지 물리적 방법으로만 해결하고 있다. 이 논문에서는 간단한 XOR연산과 부분 ID를 이용하여 다양한 공격에 안전하며 읽기전용 태그에 적합한 저비용 인증 프로토콜을 제안한다. 제안 프로토콜은 재전송, 도청, 위장 공격에 안전하며 또한 위치 프라이버시가 보장된다.

• Child Health Nursing Research
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• 제26권4호
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• pp.393-401
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• 2020

Purpose: This pilot study aimed to describe children's social contact patterns and to analyze factors related to their social contacts. Methods: The participants were 30 children aged ≥13 months to <7 years, whose teachers at childcare centers and parents at home were asked to maintain diaries of their social contacts prospectively for 24 hours. Data were collected from November 30, 2018, to January 7, 2019. Results: The 30 participating children were in contact with 363 persons in a 24-hours period (mean, 12.1±9.1). The number of contacts showed significant relationships with day of the week (p<.001), number of family members/cohabitants (p=.015), area of residence (p=.003), and type of housing (p=.002). A multiple regression model showed significantly higher numbers of contacts on weekdays (B=10.64, p=.010). Physical versus non-physical types of contact showed significant differences in terms of duration, location, and frequency (p<.001). The duration of contacts showed significant relationships with their location and frequency (p<.001), while the frequency of contacts was significantly related to their location (p<.001). Conclusion: This is the first survey describing the characteristics of Korean preschool children's social contacts. Further large-scale social contact studies of children should be conducted.

• 한국통신학회논문지
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• 제31권7C호
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• pp.755-761
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• 2006

기존 RFID 기술은 리더와 태그사이에 물리적인 접촉 없이 인식 가능하고 태그의 정보가 전송과정에 무선특성에 따른 과도한 정보 노출과 사용자의 위치정보 추적과 같은 심각한 프라이버시 침해를 유발시킨다. 특히 읽기전용 태그에서의 보안문제는 단지 물리적 방법으로만 해결하고 있다. 이 논문에서는 간단한 XOR연산과 부분 ID를 이용하여 다양한 공격에 안전하며 읽기전용 태그에 적합한 저비용 인증 프로토콜을 제안한다. 제안 프로토콜은 재전송, 도청, 위장 및 위치 추적 등 공격에 안전하다.

• 대한인간공학회지
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• 제35권5호
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• pp.449-464
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• 2016

Objective: The objective of this study is to identify essential requirements of the instrument cluster's features and layout for elderly drivers through interview and paper prototyping. Background: Recent updates implemented in passenger vehicles require more complex information to be processed by drivers. Concurrently, a large portion of the US population, the baby boomer generation has aged, causing their physical and cognitive abilities to deter. Thus it is crucial that new methods be implemented into vehicle design in order to accommodate for the deterioration of mental and physical abilities. Method: Forty elderly drivers and twenty young drivers participated in this study. The test included three sessions including: 1) location value assessment to identify the priority of areas within the instrument cluster; 2) component value assessment to capture rankings of the degree of importance and frequency of use for possible instrument cluster components; and 3) paper prototyping to collect self-designed cluster with selection of designs for each component and location of features from each participant. Results: Results revealed differences in the area priority of the instrument cluster as well as the shape and location of component features for age and gender groups. Conclusion: The study provided insights on instrument cluster layout guidelines by proving elderly driver's mental model and preferred cluster design configurations to improve driving safety. Application: LCD-based vehicle instrument cluster design, with an adaptable feature configuration for cluster components and layouts.