• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
• /
• pp.585-588
• /
• 2003

본 연구에서는 mobile IP에서의 smooth hand off시 처리율 향상 시키기 위해 방안으로 FA들 중에 지역관리를 수행하는 GFA(Gateway Foreign Agent)를 두어 FA에서 HA로의 등록 절차로 인한 전송 시간을 줄이는 방법에 관하여 연구하였다. 본 연구 결과에 의해 핸드오프가 빈번하게 일어나는 무선 인터넷 환경에서는 지역관리용 GFA를 두는 방식이 FA에 버퍼를 설치하는 방식에 비해 전송 지연면에서 개선 효과가 있음을 확인할 수 있었다. 이와 같은 결과를 최근 활성화 되고 있는 무선인터넷에 활용하면 향 후 폭발적으로 늘어날 무선 단말기의 핸드오프에 효율적으로 대응할 수 있을 것이다.

• 한국통신학회논문지
• /
• 제28권9B호
• /
• pp.834-844
• /
• 2003

Mobile IP는 고정망을 대상으로 설계된 IP를 기반으로 하기 때문에 삼각라우팅과 핸드오프에 의한 성능 측면의 저하요인을 갖고 있다. 차세대 인터넷에서는 QoS 보장형 서비스 제공이 중요 연구방향이므로 Mobile IP를 기반으로 하는 이동성 인터넷 서비스도 성능 저하요인을 보완하고, QoS 보장형 서비스를 제공하기 위한 연구가 필요하다. 본 논문은 Mobile IP에서의 QoS 보장형 서비스의 제공을 위하여 라우팅과 QoS 보장형 서비스제공을 융합한 개념인 MPLS를 전달망으로 하는 Mobile IP-over-MPLS 프레임웍의 성능향상을 위한 경로 최적화(Route Optimization)와 유연한 핸드오프(Smooth Hand-off) 방식 및 이를 지원하기 위한 MPLS LSP 설정 프로토콜인 MIP-LDP(Mobile IP-Label Distribution Protocol)를 제안한다. 제안된 방식은 기존 Mobile IP-over-MPLS 서비스망에서의 긴 전송 경로 문제와 핸드오프로 인한 패킷 손실 문제를 개선하였다.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2002년도 봄 학술발표논문집 Vol.29 No.1 (A)
• /
• pp.544-546
• /
• 2002

최근 무선 통신 기술이 빠르게 발전하면서, 모바일 사용자들의 다양한 서비스에 대한 요청이 증가하고 있다. 그리고 멀티미디어 서비스는 네트웍 효율성의 측면에서 멀티캐스트 전송 기법이 적합하다. 이에, IETF Working Group에서는 이동 컴퓨팅 환경에서 IP 멀티캐스트를 지원하기 위해 Home Subscription 과 Remote Subscription을 제안하였다[1]. 이 방법들은 각각 장.단점을 가지고 있으나, 호스트에게 연속적인 서비스를 제공하지는 못한다. 본 논문에서는 Remote Subscription에서 제공하는 최적의 경로를 사용하면서, 사용자들에게 멀티캐스트 상에서 연속적인 서비스를 제공할 수 있는 방안에 대해 제시한다. Multicast Agent는 자신이 관리하는 네트웍에 현존하는 사용자들의 멀티캐스트 그룹의 관리와 사용자들을 대신하여 그룹에 가입 및 탈퇴를 행한다. 본 논문에서 제시한 방법은 이동 가능한 지역의 Multicast Agent가 미리 멀티캐스트 그룹에 참가함으로써 기존의 제시된 연구 방법들에 비해 사용자들에게 연속적인 서비스를 제공할 수 있다.

• 한국의류학회지
• /
• 제31권1호
• /
• pp.1-10
• /
• 2007

This research was designed to compare the subjective evaluation of Hand between on- and off-line by structure and sensible characteristics of fabric. 113 subjects who have a fashion design major evaluated the subjective evaluation of Hand of various 16 kinds of specimens on- and off-line. T-test and pearson correlation coefficient were used for statistical analysis by SPSS WIN 11.0. The results of this study were as follows: The results of correlation analysis of the evaluation score indicated that Crash and Satin show high correlation between two kinds of evaluation score. But, fabrics which have distinct characteristics such as Plush, Dobby, Seersucker represented low correlation coefficient. The results of t-test fer the difference of the evaluation score showed that thin fabrics like Organdy represent a large difference between on- and off-line evaluation. On the other hand, twill weaved fabrics like Drill, Tweed, Saxony did not show many differences. Analysing each item in terms of correlation of evaluation of hand between on- and off-line gave results that the shininess was most deliverable through on-line and density and the dryness was not so deliverable through on-line. Comparison of evaluation score between on- and off-line items showed that the estimation to real fabric is more negative than that of on-line. The results of most preferable hand between on-and off-line showed exact opposite preference between shinny, smooth and soft Satin and rough, woolen Tweed. Organdy showed the most different subjective evaluation of hand in real ones compared with that of on-line.

• 한국정보과학회:학술대회논문집
• /
• 한국정보과학회 2003년도 봄 학술발표논문집 Vol.30 No.1 (C)
• /
• pp.250-252
• /
• 2003

많은 기업들이 사설망과 같은 수준의 기능을 제공하면서 사설망에 비해 매우 경제적인 VPN 을 기업 네트웍의 인프라로 채택하고 있다. VPN 을 구성하는데 있어 우수한 005 나 보안 기능을 제공하는 MPLS VPN 이 VPN 을 구성하기 위한 최적의 방법으로 간주되고 있다. 또한 모바일 컴퓨팅의 보편화와 이동 환경에서의 인터넷 서비스에 대한 요구의 증가로 VPN 에서도 이동 인터넷 서비스를 제공할 필요가 있게 되었다. 본 논문에서는 IP 의 이동성을 제공하는 Mobile IP 와 MPLS VPN 을 결합하여 VPN 이용자에게 이동 인터넷 서비스를 제공하는 방법을 설명하고 이동 노드의 핸드오프시 발생하는 패킷 손실을 최소하기 위해 Smooth handoff를 지원하는 MPLS VPN을 Linux에서 구현하고 테스트를 수행하였다.

• 한국생활과학회지
• /
• 제13권5호
• /
• pp.787-798
• /
• 2004

This research was designed to compare clothing fabric images between on- and off-line by fabric types and its characteristics. 125 subjects who have a fashion design major evaluated the fabric image of various 16 kinds of specimens on- and off-line. Frequency, x2-test, t-test, and Pearson correlation were used for statistical analysis by SPSS WIN 11.0. The results of this study are as follows: 1. The advantage of on-line shopping includes low price and purchasing convenience, etc. On-line shoppers mostly purchase clothing items, such as T-shirt and slacks. In most cases, texture of fabrics provides a main cause for the shoppers' discontentment with internet shopping. 2. The results of t-test for the difference of the evaluation score show that plain or pile weave and highly thick or thin fabrics-for example, Organdy, Corduroy, Nylon Taffeta, Plush, etc.-have a large difference between on-and off-line image. On the other hand, medium-thick twill weave-for example, Tweed, Flannel, etc.-or patterned weave-Chiffon, Dobby fabric, etc.-shows a small difference. 3. The results of correlation of the evaluation score indicate that wool twill fabrics like Tweed, Saxony, and Polafleece show a high correlation between two kinds of evaluation score. In texture preference, no correlation exists between on-line and off-line. 4. With an analysis on fabric image evaluation by fabric characteristics, smooth, shiny pink Satin was found the most positively-evaluated item in all evaluation fields except in pattern preference and individuality. On the other hand, thick olive green Corduroy was evaluated most negatively in the fields of elegance, luxury, and feminine. 5. When compared with real ones, thin fabrics provide a different on-line fabric image. For example, Nylon Taffeta and Organdy were evaluated positively on-line because of luster and pastel tone color. However, lusterless uneven cotton Seersucker was evaluated negatively. 6. Real fabrics preference is more negative than on-line ones. In addition, patterned or unique fabrics display a high agreement between the two kinds of images.

• 스마트미디어저널
• /
• 제9권4호
• /
• pp.102-108
• /
• 2020

본 논문에서는 사람의 손동작에 의해 모바일장치상의 전기장센서를 통해 감지되는 동작신호의 실시간 검출 및 프레임 추출 알고리즘을 제안한다. 동작인식에 사용되는 전기장센서는 주변 환경 및 시점에 따라 랜덤잡음 및 센서 표면의 초기 대전상태의 가변적인 특성으로 인해 안정적으로 동작신호를 검출하는데 어려움이 있다. 본 논문에서는 이와 같은 환경에서도 안정적이고 강건하게 동작신호를 감지하여 검출할 수 있는 동적문턱치 방법(dynamic thresholding method)을 제안한다. 동작발생감지여부는 10Hz low-pass 필터와 MA(Motion Average) 필터를 통한 입력신호가 특정 문턱 전압값을 넘을 경우 감지되는데 감지 시점 센서상의 정전하상태가 가변적이므로 주기적으로 offset 값을 계산하여 새로운 문턱치를 동적으로 적용하는 방법이다. 이러한 방법으로 동작신호 감지율을 98% 이상으로 향상 시킬 수 있었다. 또한 일단 동작이 감지되면 정문턱치(positive thresold)와 부문턱치(negative threshold)의 통과시점, 횟수와 평균 동작주기를 고려한 동작신호프레임 알고리즘을 제안하였으며 이의 프레임추출 성공률도 98% 이상의 성능을 보였다. 본 논문에서 제안한 알고리즘으로 추출된 동작신호는 이후 신호정규화를 거쳐 LSTN 심층신경망 인식부를 거쳐 높은 손동작 인식률을 보임으로서 제안된 알고리즘의 우수함을 입증하였다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2004년도 춘계학술대회 논문집
• /
• pp.1510-1512
• /
• 2004

Platform Screen Door System is a facility on platform to separate platform from track, having automatic sliding door structures interlocked to opening and closing of train door with integrated control unit. When a train comes to a stop at a designed position at a station, onboard ATC/ATO system transmits train berth signal to wayside signaling system. In case of automatic/driverless operation, opening and closing of the Platform Screen Door will be controlled by wayside signaling system. Unfortunately, we often see the case in news that passengers fall into track and their contact with train lead to critical accidents. However, passengers will be free from such accidents on the platform with the Platform Screen Door System. Especially during the rush hours, to ensure passenger's safety and smooth getting on & off, it is necessary to arrange. some station staffs on the platform without the Platform Screen Door System. On the other hand, the Platform Screen Door System will realize such operation by fewer staffs. Due to the above reasons, the Platform Screen Door System is becoming more popular in subway system recently.

• 한국농공학회지
• /
• 제15권3호
• /
• pp.3089-3095
• /
• 1973

The power transmission to the traction devices may be very important for the tractor performance and therefore this system has been studied very much in the past. On the other hand, the PTO(Power-take-off) has been considered as an accessary on the tractor with a few work for its power transmission. Because of increased use of PTO operation in various kind of farming operations in recent years, the function of PTO may become such important as the traction facilities. In this study, the power transmission characteristics of PTO drive was analyzed theoretically and some experimental work was done to study on it. The results of the study are as follows: 1) The most stable condition of PTO work was obtained when the intersection angle of the two curves for driving and driven torques was about ${\pi}/2$. 2) To obtain the most stable operation it is better to use both the speed control and the full control together. 3) Six steps differential gear may not be enough to use the PTO power smoothly. It is thought that the three steps differential gear on the shaft of PTO may be necessary additionally for a smooth operation. 4) When the traction facilities and the PTO are used at the same time, the torque of crank shaft becomes Tt + Tp, and the high efficiency and good stability of word will be obtained with the small variation of driving speed. 5) When the tractor was operated with 75% of the rated horse power and 70% of maximum speed, the best thermal efficiency could be obtained. 6) The most dangerous sound for human occured at the rated speed of PTO and tus it may be necessary to control the dangerous noise.

• 패션비즈니스
• /
• 제2권1호
• /
• pp.35-48
• /
• 1998

The purpose of this paper is to examine the street fashion, which is influenced by the youth culture in 1960s. Youth culture is the youth subculture which appeared multiform in the 1960s. It tried to create a new culture by subverting the ruling class culture with their combative life style and peculiar appearance which are distinguished from mother culture. Youth cultures as youth subculture are symbolically expressed in their style which had strong characteristics of sub-fashion and anti-fashion, and which are different from mother fashion in shape. Therefore youth subculture fashion had an effect on street fashion in the 60s. The influence that the youth culture fashion had had on the street fashion is summarized as follows: Beats fashion was intelligency look on black dress, black polo-neck shirts, black trousers, black glasses and heavy black eyeliner. Mods fashion was neat style on Edwardian suit with narrow trousers, pointer-toeshoes and smooth croped hair. Folkis fashion was ethnic look, middle east asian look, peasant look, Indian style, south america look, gypsy style, natural materials, natural dying, tie-dye, beads and hand made ornaments. Rockers fashion was violence appearance categorized 'blue collar' on black leather jacket decorated with metal studs and hand-painted insignia, blue jeans and boots for motor bike. Swinging London & the Psychedelics fashion was blend mods look with pschedelic color and motive pattern. Hippie fashion was intermix pschedelic and natural or ethnic style. It was appear to be a meaningless, unpredictable assortment of diverse items and style. Faded and tattered jeans, army jackets, vintage hat, beads, embroidered headband, white sheets, diverse theatrical costumes, sandals or bare feet, granny dress, peasant blouse, blanket cape, tie-dye T-shirts and long hair. Greasers fashion was adorned black leather jacket with chains, fringing, badges, insignia and sleeves had been crudely ripped off. They came to be known wore jeans so soaked with oil. Skinheads fashion was aggressive working class identity with donkey jacket, jeans rolled up, collarless union shirts, heavy boots, braces and hair cropped short.