• 한국항행학회논문지
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• 제15권4호
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• pp.517-522
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• 2011

위성항법 보정 시스템은 형태에 따라 지역보정 시스템과 광역 보정 시스템으로 나뉜다. 광역보정 시스템은 지역 보정시스템에 비해 시스템 구조가 복잡하며, 방송 메시지의 종류와 양이 많다. 또한 제한된 전송속도로 인해 사용자의 정확성과 무결성을 유지하기 위해서는 효율적인 메시지 스케쥴링이 필요하다. 현재 광역보정시스템에서는 30여 가지의 메시지가 방송되며 메시지 타입에 따라 업데이트 주기가 다르다. 본 논문에서는 메시지 스케쥴링 알고리듬을 적용하고 시뮬레이션을 통하여 성능을 분석하였다. 시뮬레이션 결과 모든 메시지 타입에서 최대 업데이트 주기 요구 조건을 만족시킴을 확인할 수 있었다.

• 정보관리학회지
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• 제40권2호
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• pp.59-80
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• 2023

기존의 연구자 유형 구분 모델은 대부분 연구성과 지표를 활용해왔다. 이 연구에서는 인용 영향력이 공동연구와 관련이 있다는 점을 감안하여 인용 데이터를 활용하지 않고 공동연구 지표만으로 연구자 유형을 분석하는 새로운 방법을 모색해보았다. 공동연구 패턴과 공동연구 범위를 기준으로 연구자를 Sparse & Wide (SW) 유형, Dense & Wide (DW) 유형, Dense & Narrow (DN) 유형, Sparse & Narrow (SN) 유형의 4가지로 구분하는 모델을 제안하였다. 제안된 모델을 양자계측 분야에 적용해본 결과, 구분된 연구자 유형별로 인용지표와 공저 네트워크 지표에 차이가 있음이 통계적으로 검증되었다. 이 연구에서 제시한 공동연구 특성에 따른 연구자 유형 구분 모델은 인용정보를 필요로 하지 않으므로 연구관리 정책과 연구지원서비스 측면에서 폭넓게 활용할 수 있을 것으로 기대된다.

• Journal of Power Electronics
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• 제18권5호
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• pp.1303-1314
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• 2018

To match the dynamic lower voltage of a fuel cell stack and the required constant higher voltage (400V) of a DC bus, an H-type structural Boost three-level DC-DC converter with a wide voltage-gain range (HS-BTL) is presented in this paper. When compared with the traditional flying-capacitor Boost three-level DC-DC converter, the proposed converter can obtain a higher voltage-gain and does not require a complicate control for the flying-capacitor voltage balance. Moreover, the proposed converter, which can draw a continuous and low-rippled current from an input source, has the advantages of a wide voltage-gain range and low voltage stress for power semiconductors. The operating principle, parameters design and a comparison with other converters are presented and analyzed. Experimental results are also given to verify the aforementioned characteristics and theoretical analysis. The proposed converter is suitable for application of fuel cell systems.

• IEIE Transactions on Smart Processing and Computing
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• 제6권4호
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• pp.299-304
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• 2017

A wireless passive sensor network is a network consisting of sink nodes, sensor nodes, and radio frequency (RF) sources, where an RF source transfers energy to sensor nodes by radiating RF waves, and a sensor node transmits data by consuming the received energy. Against theoretical expectations, a wireless passive sensor network suffers from many practical difficulties: scarcity of energy, non-simultaneity of energy reception and data transmission, and inefficiency in allocating time resources. Perceiving such difficulties, we propose a simple contending-type medium access control (MAC) scheme for many sensor nodes to deliver packets to a sink node. Then, we derive an approximate expression for the network-wide throughput attained by the proposed MAC scheme. Also, we present an approximate expression for the optimal partition, which maximizes the saturated network-wide throughput. Numerical examples confirm that each of the approximate expressions yields a highly precise value for network-wide throughput and finds an exactly optimal partition.

• KIEAE Journal
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• 제7권6호
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• pp.107-112
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• 2007

Recently hybrid beam system is widely used because it has many structural advantages such as short construction period and low story height etc. Generally steel wide flange beam exposure type and embedded type hybrid beams are constructed. Even though exposure hybrid beam is easily constructed, the fire proofing protection process is necessary because steel wide flange beam cannot resist to fire itself. Story height reduction type hybrid beam, which is introduced hybrid beam in this paper, does not need fire proofing protection process because it is constructed as a fully embedded type hybrid beam. Developed construction process and actual construction cases of story height reduction type hybrid beam were introduced in this study.

• 한국의류학회지
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• 제25권8호
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• pp.1420-1431
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• 2001

This research was done to classify lower body types by direct measurements, side and back view types from waistline to gluteal furrow line individually, and to analyze correspondence these lower body types with side and back view types from waistline to gluteal furrow line. The subjects of this study were 191 female college students from 18 to 25 years old residing in Pusan urban area. Type 1(long and slim) of lower body types by direct measurements was correspond with Type 1(slim curve) and Type 4(slim and protrusive hip) of side view and Type 3(wide and curve) and Type 4(trapezoid shape) of back view. Type 2(short and thick) of lower body types was correspond with Type 3(thick and droopy hip) of side view and Type 1(wide and straight) of back view. Type 3(short and slim) of lower body types was correspond with Type 2(slim and flat hip) of side view and Type 2(narrow and curve) of back view.

• International Journal of Costume and Fashion
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• 제3권
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• pp.13-24
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• 2003

The purpose of this study was to examine the changes brought by the upper body form using a three-dimensional human body measurement the gypsum method. The developed plane figure was constructed using paper replica to analyze the dimensional shape of the upper torso and to be able to design clothes suitable for elderly women's physical characteristics. The characteristics are analyzed and compared with existing patterns in order to extract the components for the pattern design. The examination was carried out based on the developed plane figures of upper body surface replicas. Type 1, the bent-forward body form, has a wide gap on the shoulder. In Type 2, the gap of waist line was wide at angulus scapulae point. Type 3 was the thin body form, and the girth of the chest, front interscye breadth and back interscye breadth were more level with one another, compared to the other types. In Type 4, the bent-backward body form, there was a wide gap on front shoulder. Comparison with the developed plane figure and existed pattern, items revealed differences in significance included the front and back interscye width between the measured values of the existed patterns and the developed plane figure. Therefore, the basic components of basic bodice pattern for old women were determined in the up-bust circumference and length of the back.

• 전자공학회논문지B
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• 제32B권1호
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• pp.127-135
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• 1995

The diffusion neural network forms a Gaussian distribution by transferring an excitation to the surround. A DOG(difference of two Gaussians) is obtained by the diffusion neural network. This type of the DOG, which can detect the intensity changes of an image, has the same shape as a LOG(Laplacian of a Gaussian:${\Delta}^2$G) and narrow band pass characteristics. In this paper we show that another type of the DOG which has a very narrow Gaussian for the excitatory and a very wide Gaussian for the inhibitory, can be formed by the diffusion process of this network, This type of the DOG has a wide band width in spatial frequency domain and can be used efficiently in detecting special type of edges.

• 한국의류산업학회지
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• 제15권3호
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• pp.414-422
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• 2013

This study identifies the foot shapes of elderly men by classifying foot types according to the shapes of sole of foot and analyzing individual characteristics. The subjects were 269 elderly men over 60 years of age. Their right feet were measured indirectly with a 2D scanner. The anthropometric measuring items consisted of 38 items that were estimated on the right foot of each subject. The 2D scan data were analyzed by various statistical methods such as factor analysis, ANOVA and cluster analysis using the statistical program SPSS 19.0. A total of 8 factors were extracted through a factor analysis and these factors represent 77.83% of total variance. The 8 factors were: ball and lateral foot protrusion, ball gradient, medial foot protrusion, anterior and posterior foot length ratio, lateral ball length, heel size, toes breadth, and foot length, that explained 77.83% of the total variance. A total of 4 clusters (as their sole type) were categorized using 8 factor scores by cluster analysis. Type 1 was classified as H-type(toes width, foot width, heel width uniform and medial malleolus and lateral malleolus almost no protrusion). Type 2 was classified as V-type(foot width and toes width, wide and heel width narrow). Type 3 was classified as A-type(foot width and heel width, wide but toes width narrow, protruded inside). Type 4 was classified as D-type(protruded outside).

• 한국의류산업학회지
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• 제20권1호
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• pp.75-82
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• 2018

This study was attempted to clarify differences in sizes and shapes of foot between 20's and 60-70's women and analyzed the characteristics of elderly women's foot shapes as compared with those of young. The 2D data were 101 elderly and 101 young women in Seoul and Gyeonggi-do. The results are as follows: Firstly, the foot length of the elderly was shorter than that of the young, the foot breadth and the heel width were widened, but the toes breadth became smaller and the deformity of the toe 1 and the first metatarsal part appeared. Secondly, in the Foot Index, there was a significant difference in age group, the young is more than the elderly in the narrow type, standard type, the elderly women showed more than three times the young in the wide type. Thirdly, in the factor analysis for the foot type classification, 'foot length' factors in both age groups were large. Next, young group were influenced by 'toes breadth', lateral ball breadth' factors, elderly group was influenced by the 'lateral ball breadth', 'medial ball breadth' factors. Lastly, in the cluster analysis of the elderly group, the types of sole were classified as W-Type(20.8%, wide foot and toes, large heel), H-type(20.8%, small toes breadth, heel), D-type(31.7%, long length and wide lateral ball) and A-Type(26.7%, which is found only in the elderly, small length and large toes angle). As a result, it is necessary to design the shoes that match the characteristics of the soles of the elderly women.