• 디지털산업정보학회논문지
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• 제12권3호
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• pp.299-309
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• 2016

This study proposed a logistics plan for sending supply to be distributed to areas other than producing areas to wholesalers and allocating supply to be distributed to areas near producing areas to local distribution center in the vicinity instead of shipping the entire quantity to wholesalers for fruits auction to increase the competitive edge of the domestic fruits and vegetables logistics market in the ear of infinite competition. A video auction-based short distance division logistics operation model was developed to enhance competitiveness related to the circulation of fruits and vegetables, reduce logistics costs, and rationalize logistics by distributing the items sent to wholesalers through field auction and the shipments at local distribution center to neighboring areas through video auction connected to wholesalers real-time. The study especially came up with a logistics rationalization plan by examining and analyzing the stages and costs of transportation between producing areas and wholesalers on the circulation routes of fruits.

• 한국해양공학회지
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• 제36권5호
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• pp.340-352
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• 2022

This article presents a modeling method for the uncorrelated measurement error of the ultra-short baseline (USBL) acoustic positioning system for aiding navigation of underwater vehicles. The Mahalanobis distance (MD) and principal component analysis are applied to decorrelate the errors of USBL measurements, which are correlated in the x- and y-directions and vary according to the relative direction and distance between a reference station and the underwater vehicles. The proposed method can decouple the radial-direction error and angular direction error from each USBL measurement, where the former and latter are independent and dependent, respectively, of the distance between the reference station and the vehicle. With the decorrelation of the USBL errors along the trajectory of the vehicles in every time step, the proposed method can reduce the threshold of the outlier decision level. To demonstrate the effectiveness of the proposed method, simulation studies were performed with motion data obtained from a field experiment involving an autonomous underwater vehicle and USBL signals generated numerically by matching the specifications of a specific USBL with the data of a global positioning system. The simulations indicated that the navigation system is more robust in rejecting outliers of the USBL measurements than conventional ones. In addition, it was shown that the erroneous estimation of the navigation system after a long USBL blackout can converge to the true states using the MD of the USBL measurements. The navigation systems using the uncorrelated error model of the USBL, therefore, can effectively eliminate USBL outliers without loss of uncontaminated signals.

• 정보처리학회논문지C
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• 제10C권3호
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• pp.335-344
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• 2003

무선 정보 환경의 변화에 따라 다양한 정보에 대한 풍족감이 요구되고 이에 따라 많은 근거리 무선 통신 기술들이 연구 개발되어 왔으며, 그 중에서도 최근 근거리 무선 통신의 표준으로 각광받고 있는 블루투스와 무선랜은 많은 관심을 받고 있다. 그러나 근거리 무선 통신을 실제 무선 환경에 적용하기엔 많은 문제점들이 제기되고 있다. 따라서 본 논문에서는 현재 근거리 무선 통신의 보안적 취약점 뿐만 아니라 무선 환경이라는 특수한 환경에서 보안적 사항과 사용자의 프라이버시와 밀접한 관계가 있는 비보안적인 사항까지 고려한 일반화된 중앙 집중형 보안 모니터링 기법을 제안한다. 또한 제안된 방식을 근거리 무선 통신의 대표적인 기술인 블루투스와 무선랜에 적용시켜 사용자 중심으로 흩어져 있는 모바일 디바이스에 대한 안전한 보안 모니터링 기법을 제안한다.

• 대기
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• 제15권4호
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• pp.229-239
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• 2005

The effect of inversion layer on the land and sea breeze near the Gangneung city was investigated. The land and sea breeze occurrence days were selected, and the height and the intensity of inversion layer were calculated with the upper air observational data of the Sokcho Station. The relationships between the temperature variation near the Gangneung and the inflow time, inland penetration and the inflow depth of the land and sea breeze were also analyzed. And the Gangwon Short-range prediction system was verified with the comparison of surface stream line by the Gangwon short-range prediction system with the AWS wind vector data. It was revealed that the inversion layer tended to block the sea breeze, shorten the inland penetration distance and lower the inflow depth, causing the temperature rise. The comparison and analysis of surface steam line by the Gangwon short-range prediction system and the AWS wind vector showed that the system quite well simulated the sea breeze, thus the system could be well utilized in the prediction of land and sea breeze.

• 한국초지조사료학회지
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• 제38권4호
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• pp.343-348
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• 2018

In this study, the effect of daily short-distance walking exercise on milk production and metabolic status of the lactating dairy cows was investigated. The experiment was conducted with 10 lactating dairy cows comprising 2 groups (5 dairy cows/group), which were walking activity and non-walking activity. The walking activity (WA) group lactating dairy cows walked outdoors for 1 km/d, and the non-walking activity (non-WA) lactating dairy cows were maintained within a cowshed from $18^{th}$ April to $30^{th}$ May. The activity volume of the neck was not significantly different between the groups, but the activity volume of the leg was higher in WA group compared with non-WA (p<0.05). The rectal temperature was higher in the WA group ($38.6^{\circ}C$) compared with non-WA ($38.2^{\circ}C$) (p<0.05). No significant differences in dietary NE intake, milk production and milk composition were found between the groups. The plasma cortisol concentration was higher in WA group ($2.14{\mu}g/dl$) compared to non-WA ($0.95{\mu}g/dl$) (p<0.05). However, plasma cortisol level of WA dairy cows was significantly decreased as compared with non-WA cows. On the contrary, the level of plasma melatonin was increased in WA cows than that of non-WA dairy cows. It may be interpreted as a change in physical fitness. From this study, we suggest that walking activity can be improved energy balance. Further investigation is needed to determine whether different combinations of distance, rate or doing in morning or afternoon will stimulate energy balance.

• 대한전자공학회논문지TC
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• 제43권11호
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• pp.78-84
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• 2006

본 논문에서는 무선 센서 네트워크(Wireless Sensor Networks)의 표준 중에서 근거리 무선 통신 기술인 지그비(Zigbee) 네트워크에 이동성을 부여하는 방법에 대하여 제안한다. 지그비는 매우 저렴한 가격, 매우 긴 배터리 수명, 간단한 구조 및 연결성을 제공하여 $10m{\sim}70m$이내의 작은 범위 내에서 무선 연결을 요구하는 분야에 적합한 표준이다. 하지만 지그비 네트워크에서는 이동성을 지원하고 있지 않기 때문에 실제 필드(Field)에서 발생하는 다양한 변화에 적응력 있게 대처할 수 있도록 추가로 지원되어야 할 요소들이 연구되어야 한다. 본 논문에서는 지그비 네트워크에 이러한 문제점을 해결하기 위하여 지그비 엔드디바이스(End Device)가 현재 라우터(Router) 영역에서 다른 라우터 영역으로 이동했을 때 지그비 엔드 디바이스의 주소 변경으로 인한 기존의 연결 및 바인딩 테이블(Binding Table)을 다시 수립해야 하는 문제점을 해결하여 연결의 끊김 및 데이터의 손실 없이 통신을 할 수 있도록 하는 방안을 제안한다.

• Journal of Electrical Engineering and Technology
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• 제13권2호
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• pp.591-598
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• 2018

Short term load forecasts complexly affected by socioeconomic factors and weather variables have non-linear characteristics. Thus far, researchers have improved load forecast technologies through diverse techniques such as artificial neural networks, fuzzy theories, and statistical methods in order to enhance the accuracy of load forecasts. Short term load forecast errors for special days are relatively much higher than that of weekdays. The errors are mainly caused by the irregularity of social activities and insufficient similar past data required for constructing load forecast models. In this study, the load characteristics of Lunar New Year's Day holidays well known for the highest error occurrence holiday period are analyzed to propose a load forecast technique for Lunar New Year's Day holidays. To solve the insufficient input data problem, the similarity of the load patterns of past Lunar New Year's Day holidays having similar patterns was judged by Euclid distance. Lunar New Year's Day holidays periods for 2011-2012 were forecasted by the proposed method which shows that the proposed algorithm yields better results than the comprehensive analysis method or the knowledge-based method.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.703-706
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• 2008

Large distortion is made by toed-in camera configuration in the TV condition that has short viewing distance, when the gaze position of a stereoscopic image coincides with that of real space. Therefore, in the TV condition, we confirmed that the proper camera configuration is the modified parallel configuration, and found distortionless optimal stereoscopic image condition using this camera configuration.

• Journal of Species Research
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• 제11권4호
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• pp.330-334
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• 2022

Mesorhabditis microbursaris (Steiner, 1926) Sudhaus, 2011, belonging to the family Mesorhabditidae (Rhabditomorpha), is newly reported from South Korea. During a survey of small streams, M. microbursaris was isolated from sedimentary soil samples. The genus Mesorhabditis Osche, 1952 nematodes are distributed all over the world and are mostly found from terrestrial habitats, however are sometimes found in freshwater. At present, 34 valid species have been recorded from Mesorhabditis; however, only three species have been reported from South Korea. Mesorhabditis microbursaris exhibits morphological characters of other congeneric species, including shorter distance between vulva and anus than the distance between anus and tail, rudimentary bursa with narrow velum and short genital papillae, shorter spicules than tail and conical tail. However, this species can be distinguished from other Mesorhabditis species by its morphometric characters and three pairs of bursal papillae. Details of the morphological characteristics and morphometrics of M. microbursaris are described and illustrated based on optical microscopy.

• Asian-Australasian Journal of Animal Sciences
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• 제12권8호
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• pp.1171-1176
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• 1999

The precision and reliability of the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section scans was evaluated by the repeatability (R) and coefficient of variation (CV) for error variance. The 6th and 7th ribs cross section of carcasses from 55 fattened Japanese Black steers were used. The image analysis was conducted using a desk top computer (Macintosh-Apple Vision 1710 Display) connected to a scanner and an image capture camera. Two software applications, Adobe Photoshop and Mac Scope were used interchangeably. The information extracted and measured were individual muscle area, circumference length, long and short axes lengths, muscle direction; distance between any two muscle centers of gravity; cross section total area, lean, fat, and bone. The information was extracted after the processes of scanning, digitization, masking, muscle separation, and binarization. When using the Computer Image Analysis technique by desk top computer, proper digitization and selection of scanning resolution are very important in order to obtain accurate information. The R-values for muscle area, circumference, long and axes lengths, and direction ranged from 0.95 to 0.99, whereas those of the distance between any two muscle centers of gravity ranged from 0.96 to 0.99, respectively. For the cross section total area, lean, fat, and bone it ranged from 0.83 to 0.99. Excellent repeatability measurements were observed for muscle direction and distance between any two muscle centers of gravity. The results indicate that the Computer Image Analysis technique using a desk top computer for extracting information from carcass cross section is reliable and has high precision.