• 한국추진공학회:학술대회논문집
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• 한국추진공학회 1998년도 제10회 학술강연회논문집
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• pp.13-13
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• 1998

A simple model of the tip leakage flow models of the rotor downstream flow is developed, based on Lakshminarayana's theoretical concept on the tip clearance flow and the experimental data published in open literature. And new spanwise distribution models of deviation angle and pressure loss coefficient due to the tip leakage flow are formulated for use in association with the streamline curvature method as a through flow analysis. Combining these new models and previous deviation and loss models due to secondary flow, a robust streamline curvature method is established for flow analysis of single-stage, subsonic axial turbines with wide ranges of turning angle, aspect ratio and blading type. At the exit from rotor rows, the flow variables are mixed radially according to a spanwise transport equation. The proposed streamline curvature method is tested against a forced vortex type turbine as well as a free vortex type one. The results show that the spanwise variations of flow angle, axial velocity and loss coefficients at rotor exit are predicted with good accuracy, being comparable to a steady three-dimensional Navier-Stokes analysis. This simple and fast flow analysis is found to be very useful for the turbine design at the initial design phase.

• 산업경영시스템학회지
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• 제43권4호
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• pp.67-75
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• 2020

This paper proposes a methodology for gantry route optimization in order to maximize the productivity of a odd-type surface mount device (SMD). A odd-type SMD is a machine that uses a gantry to mount electronic components on the placement point of a printed circuit board (PCB). The gantry needs a nozzle to move its electronic components. There is a suitability between the nozzle and the electronic component, and the mounting speed varies depending on the suitability. When it is difficult for the nozzle to adsorb electronic components, nozzle exchange is performed, and nozzle exchange takes a certain amount of time. The gantry route optimization problem is divided into the mounting order on PCB and the allocation of nozzles and electronic components to the gantry. Nozzle and electronic component allocation minimized the time incurred by nozzle exchange and nozzle-to-electronic component compatibility by using an mixed integer programming method. Sequence of mounting points on PCB minimizes travel time by using the branch-and-price method. Experimental data was made by randomly picking the location of the mounting point on a PCB of 800mm in width and 800mm in length. The number of mounting points is divided into 25, 50, 75, and 100, and experiments are conducted according to the number of types of electronic components, number of nozzle types, and suitability between nozzles and electronic components, respectively. Because the experimental data are random, the calculation time is not constant, but it is confirmed that the gantry route is found within a reasonable time.

• 한국의상디자인학회지
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• 제18권1호
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• pp.149-168
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• 2016

The Saka were a large group of Eastern Iranian nomadic tribes on the Eurasian Steppe. The sythian figures shown on the Persian reliefs are esteemed as the only empirical material in the range of scythian costume researches. The study of the scythian culture is an important part in the research of possible connections of our cultural roots with this region. The investigation was initiated by the theory, that the korean people emigrated from the Eurasian region, so that their origin can linked to eurasian riding people. The aim of this study is to organize the scythian clothingform in a typological system. This results shall be used as the starting point for research investigating the origin of the korean clothingform. This study refers to data, which has been extracted from reviews of literature, articles and excavation data of German Archaeological Institute. Results of this study are as follows: The basic form of clothing shown on the Persian reliefs is the upperjacket with narrow sleeve and trousers. This basic form is divided into two different types. 1)The median tunicform upperjacket('Sarapis') and median narrow trousers('Anaxsirides'), which is bound with its end shoes. 2)The Scythian 'Cutaway' upperjacket that is cut from the front in the middle to the knee with the diagonal lines and relatively wide trousers. They wore high pointed hats with flaps over ears and the nape of the neck. The first median type is dated from the $6^{th}$ century BC. and the second type can be found on reliefs from the $5^{th}$ century BC. Reliefs. In the meantime appeared a mixed form, namely scythian Jacket and median trousers. From this analysis could be observed that scythian clothingform has changed by median type to the scythian type. The Scythians shown on the Persian reliefs are divided into three group according to the regions where they lived: Saka-paradraya, Saka-tigraxauda, Saka-haumavarga. Clothingstype is different depending on the group. The clothesform is also used as a good parameter to distinguish scythian groups.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -1
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• pp.92-96
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• 2000

In this paper, we propose a call admission control(CAC) scheme fer the mixed voice/data DS-CDMA systems and analyze the Er-lang capacity under the proposed CAC scheme. Voice and data traffics require different system resources based oil their Quality of Service(QoS) requirements. In the proposed CAC scheme, some system resources are reserved exclusively for handoff calls to have high priority Over new calls. Additionally the queueing of both new and handoff data traffics that are not sensitive to delay is allowed. Ar a performance measure for the suggested CAC scheme. Erlang capacity is utilized. For the performance analysis, a four-dimensional Markov chain model is developed. Erlang capacity of a practical IS-95B type system depicts, and optimum values of system parameters such as the number of reservation channels and queue lengths are found with respect to Erlang capacity. Finally, it is observed that Erlang capacity is improved more than two times by properly selecting the system parameters with the proposed CAC scheme.

• Animal Bioscience
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• 제35권3호
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• pp.377-384
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• 2022

Objective: This study was conducted to estimate multi-trait genetic parameters for somatic cell score (SCS), milk yield and type traits in Nigerian Dwarf (ND) goats from the United States. Methods: Data from 1,041 ND goats in the United States with kiddings in 95 herds were used to estimate multi-trait genetic parameters for SCS, milk (MILK), fat (FAT), and protein (PROT) yields, and 14 type traits. An 18-trait mixed linear animal model for lactation mean SCS (Log₂), MILK, FAT, PROT, and 14 type traits was applied. A factor analytic approach (FA1) in ASReml software was used to obtain convergence. Results: Averages for SCS were low (2.85±1.29 Log₂), and were 314±110.6, 20.9±7.4, and 14±4.9 kg, respectively, for MILK, FAT, and PROT. Heritabilities for SCS, MILK, FAT, and PROT were 0.32, 0.16, 0.16, and 0.10, respectively. The highest heritabilities for type traits were for stature (0.72), teat diameter (0.49), and rump width (0.48), and the lowest estimates were for dairyness (0.003) and medial suspensory ligament (0.03). Genetic correlations of SCS with MILK, FAT, and PROT were positive but low (0.25, 0.18, and 0.23, respectively). Genetic and phenotypic correlations between MILK, FAT, and PROT were high and positive (≥0.66). Absolute values of genetic correlations involving SCS with type traits were generally low or no different from zero. Most of the phenotypic correlations involving SCS with type traits were low. No serious unfavorable genetic correlations between milk yield traits and SCS or between milk yield traits or SCS and type traits were found. Conclusion: Genetic variation exists in the ND breed for most studied traits. The development of selection programs based on these estimates may help accelerate favorable multi-trait genetic changes in this breed.

• 한국지리정보학회지
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• 제20권3호
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• pp.90-103
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• 2017

본 연구는 도심온도 저감을 위한 녹지의 기능을 규명하기 위하여 여름철 고온 시간대에 도심녹지에서 나타나는 표면온도 특성을 분석하였다. 도시 내 고립된 녹지인 익산 소라산 자연마당을 대상으로 고해상도 UAV 영상을 활용하여 정밀한 표면온도 자료를 취득하였고, 피복유형, 식생유형, 수종유형, 수종별 녹지용적과 표면온도와의 관계를 분석하였다. 연구결과 피복유형 중 습지와 산림은 저온역, 포장지는 표면온도가 월등히 높은 고온역으로 확인되었다. 식생유형에서는 산림 내 침엽수보다 활엽수의 표면온도가 낮았고, 조경수식재지 내에선 활엽수보다 침엽수의 표면온도가 낮은 반대의 결과가 확인되었다. 장초지보다 단초지의 표면온도가 높아 초지의 용적에 따른 온도차이가 확인되었다. 산림수종유형별 표면온도는 침엽수인 소나무림보다 활엽수인 아까시나무림과 활엽수혼효림의 표면온도가 낮았고, 활엽수혼효림과 아까시나무림간의 미세한 표면온도 차이가 확인되었다. 산림수종유형별 녹지용적과 표면온도 분석결과 소나무림과 활엽수혼효림에서는 기존 연구 결과와 유사하게 녹지용적 증가에 따라 표면온도가 감소하는 음의상관관계가 확인되었다. 그러나 아까시나무림은 용적의 증가에 따라 미세하게 표면온도가 상승하는 약한 양의상관관계가 확인되어 수종에 따라서는 용적과 온도의 일관된 상관성에 예외가 있을 수 있음을 확인하였다. 향후 침엽수와 활엽수간 차이, 용적과 온도의 관계, 수종별 차이 등 녹지의 세부적 속성과 온도의 관계에 관하여 정밀한 공간자료를 활용한 다각적인 연구가 계속되어야 할 것으로 판단된다.

• 인터넷정보학회논문지
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• 제17권4호
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• pp.43-50
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• 2016

본 논문은 차량용 지능형 네트워크에서 각광 받게 될 이더넷중심의 프로토콜과 데이터 전송 시 임의의 오류에 내성이 있는 알고리즘을 제안하였다. 동시에 시뮬레이션과 실험을 통해 구현과 검증을 시도하여 시스템의 유용성을 증명하였다. 기존의 차량 통신 서비스 시스템에 적용시키기 위한 알고리즘에 대하여 문헌 조사하고 최종적으로 새로운 알고리즘을 구현하였다. 실제 차량용 실시간 데이터의 경우 임의의 값이 불규칙적으로 발생하기 때문에 임의의 데이터를 생성하여 실험을 진행하고 payload의 설정을 표준 형식에 맞추었다. 구현된 알고리즘의 성능을 확인하고자 기존의 알고리즘에서 단일 데이터에서부터 혼합형 (Hybrid-type) 데이터까지 확인하였을 때의 문제점을 확인하고 제안하는 알고리즘의 실효성을 확인하였다.

• 한국컴퓨터정보학회논문지
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• 제25권2호
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• pp.59-66
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• 2020

본 논문에서는 저전력 무선 음향센서 모듈을 통한 데이터 수집과 딥 오토인코더를 이용한 데이터 분석을 통해 배관의 누출을 탐지하는 시스템을 제안한다. 데이터 통신량을 줄이기 위해서 푸리에 변환을 통해 음향센서 데이터 양을 약 1/800로 감소시키는 저전력 무선 음향센서 모듈을 구성하였고, 20kHz~100kHz 주파수 신호를 이용하여 가청 주파수 대역에서 발생하는 노이즈에 강인한 누출 탐지 시스템을 설계하였다. 또한, 데이터 양의 감소에도 배관 누출을 정확하게 탐지하도록 딥 오토인코더를 이용한 데이터 분석 기법을 설계하였다. 수치적인 실험을 통해, 본 논문에서 제안한 누출 탐지 시스템이 고주파 대역대의 노이즈가 섞인 환경에서도 99.94%의 높은 정확도와 Type-II error 0%의 높은 성능을 보이는 것을 검증하였다.

• 한국의류학회지
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• 제18권5호
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• pp.716-726
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• 1994

The present study was conducted to analyze the type of appeal and constituent unit's expression of apparel advertising appeared in women's magazine through content analysis. The research questions raised for this study were: (1) Are there any differences in the type of appeal between outwear and uderwear, men's and women's outwear, and formal wear and casual wear advertising ? (2) Are there any differences in the type of appeal and constituent unit's expression of apparel advertising between the late of 1980's and the begining of 1990's ? "Women Sense", founded on August 1988, was used as research materials for the study. And the period of analysis was from September 1988 to March 1993. In order to reduce biases of monthly issues in magazine, the apparel advertisements for analysis were selected from March, June, September and December issues. A total of 348 apparel advertisements were analyzed. The data gethered were analyzed using the frequency table, percentage and chi-square test. The results were as follows: 1. The emotional appeal was used more often for apparel advertisements. 2. There was no difference in types of appeal between men's and women's outwear. Both of them frequently used emotional appeal type 3. Rational appeal and sex appeal type were used more frequently in underwear advertising than in outwear advertisements. 4. It was emotional appeal type that usually used in both formal and casual wear advertising, and sex appeal was employed more often in casual wear advertising than in formal wear advertising. 5. Romantic appeal was employed more aften in the late of 1980's than in the begining of 1990's. Sex appeal and rational appeal were used more often in the beginning of 1990's than in the late of 1980's. 6. Emotional (28.7%) and Assertion Propose Headlines (21.6%) were popular in the late of 1980's. 7. Brand Name Headline was shown most often in the begining of 1990's. 8. Emotional, Factual and Mixed Copies were generally used at all types of bodycopy. while there was no difference in types of bodycopy between the periods. 9. Direct Approach, that a model introduced advertising goods to consumer, was mainly used in illustration. There was no difference in different types of illustration between the periods.

• 한국컴퓨터정보학회논문지
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• 제24권4호
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• pp.137-144
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• 2019

The purpose of this study was to provide basic data for the development of a prototype of a garment that allows middle aged men to look idealized by examining the type of perception of middle aged men based on their subjective evaluation and their characteristics. This study used the Q methodology, which is a subjective research method that finds correlations among middle aged men across subjective attributes. The types of perception of body shape of middle aged men were analyzed as three types: leaning forward shape with bird legs, developed upper body shape with thick legs, protruding abdomen obesity body shape. The leaning forward shape with bird legs was recognized as the lowest in the BMI index, and the shoulder and chest were sagging, legs were thinner than the body and leaned forward. And that the hip were protruding and had a flat rectangular shape. Developed upper body shape with thick legs was the second overweight type of BMI index. It was recognized that the ankle and calf thighs were thick and the upper abdomen protruded upper body development body. Protruding abdomen obesity body shape was the most obese type with BMI index. In this type, the height was the smallest, and the upper abdomen came out and the abdomen protruded, and the abdomen was more exuded than the chest, and the neck was thick and the hips were recognized as the big body. The middle aged men's recognitive body shape was classified as a similar to actual body shape. However, in the recognition type, the frontal and side body types were mixed and classified. It is necessary to study the ergonomic pattern considering the features of each body type. This suggests that psychological effects can be obtained that allow the body shape that changes with age to be accepted more positively.