• 제목/요약/키워드: Classification of Difficulty

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작업 시간과 자세위험도를 고려한 군 보급시설 수리부속 배치대안 결정 (Decision Making for the Arrangement of Spare Parts in Military Warehouse, considered on Working Time and Posture Difficulty)

  • 김경록;차종한
    • 한국산학기술학회논문지
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    • 제14권10호
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    • pp.4893-4901
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    • 2013
  • 방위 산업에서는 무기체계라 말하는 장비가 목표 수명동안 지속적으로 사용 할 수 있도록 설계에서부터 정비까지 많은 분야에 걸쳐 연구가 이루어지고 있다. 하지만, 장비를 수리하는데 필요한 수리부속이 저장 및 불출되는 군 보급 시설의 운용 관리는 현실적 연구가 부족한 상황이다. 그래서 이 글에서는 군 보급시설의 효율적인 운용 관리를 위하여 저비용 고효율을 얻을 수 있는 수리부속 배치에 대한 연구를 제시한다. 먼저, 수리부속을 MTBF(Mean Time Between Failure) 기준 하에 A/B/C 그룹으로 나누어 기본적인 배치 대안들을 정의한다. 이렇게 정의된 대안들은 시뮬레이션과 작업 자세 평가 도구인 RULA(Rapid Upper Limb Assessment)를 통해 대안 선정에 필요한 평가 속성인 작업 시간과 자세 위험도를 도출하고, 이를 엔트로피 척도를 통해 대안 결정을 한다. 본 연구는 작업 시간과 자세 위험도를 최소화 하여 군 보급 시설 내 효율적인 수리부속 배치 방법을 제시하였다. 이는 군 보급시설의 시스템 및 인간공학적 접근을 함께 고려한 점에서 앞으로의 연구에 새로운 방향을 제시하였다 할 수 있다.

십오락맥(十五絡脈)의 종류와 분포특징에 관한 문헌적 고찰 (Review on the Classification and Distribution of Fifteen Main Collaterals)

  • 김태한;임윤경
    • Korean Journal of Acupuncture
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    • 제23권2호
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    • pp.29-38
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    • 2006
  • Objectives & Methods: This study was aimed to investigate denomination and distribution of fifteen main collaterals through oriental medicine literature. Results & Conclusions: 1. Kyung-maek-pyoun(經脈篇) of Yeong-chu (靈樞; divine pivot) says that fifteen main collaterals (十五絡脈) consist of main collaterals of the twelve regular meridians (十二經脈), Conception Channel (任孤), Governor channel (督脈) and great collateral of the spleen(脾之大絡). While chapter 26 of Nan-gyung(難經; Classic of difficulty) says that Yin-heel & Yang-heel channels are included instead of Conception channel(任脈) and Governor Channel (督脈). what is explained in Yeong-chu (靈樞; divine pivot) is considered more proper. 2. Great collateral of the stomach (胃之大絡 ) has been considered as one of the main collaterals, resulting in an opinion of sixteen main collaterals. We speculate that this is a wrong interpretation of Pyoung-in-gi-sang-lon(平人氣象論 ) of So-mun(素問). 3. Gumi (CV1) is more resonable than Hoeeum(CV14) for the Connecting point of Conception Channel(任脈) 4. Kyung-maek-pyoun (經脈篇) of Yeong-chu (靈樞; divine pivot) did not mention that the collateral of Hand Jueyin (手厥陰絡版) was running to Hand Shaoyang(手少陽經脈), which is considered to be omitted by mistake. 5. Fifteen main collaterals are mostly distributed on the legs and arms, while some are distributed in the internal organs, chest, abdomen, as well as head and five sensory organs.

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Characteristics of crater formation due to explosives blasting in rock mass

  • Jeon, Seokwon;Kim, Tae-Hyun;You, Kwang-Ho
    • Geomechanics and Engineering
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    • 제9권3호
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    • pp.329-344
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    • 2015
  • Cratering tests in rock are generally carried out to identify its fragmentation characteristics. The test results can be used to estimate the minimum amount of explosives required for the target volume of rock fragmentation. However, it is not easy to perform this type of test due to its high cost and difficulty in securing the test site with the same ground conditions as the site where blasting is to be performed. Consequently, this study investigates the characteristics of rock fragmentation by using the hydrocode in the platform of AUTODYN. The effectiveness of the numerical models adopted are validated against several cratering test results available in the literature, and the effects of rock mass classification and ground formation on crater size are examined. The numerical analysis shows that the dimension of a crater is increased with a decrease in rock quality, and the formation of a crater is highly dependent on a rock of lowest quality in the case of mixed ground. It is expected that the results of the present study can also be applied to the estimation of the level and extent of the damage induced by blasting in concrete structures.

노년남성의 체형별 상의 치수 체계 (The Upper Garment Sizing Systems according to Somatotype of Elderly Men)

  • 김수현;이정란
    • 한국의류학회지
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    • 제29권1호
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    • pp.157-166
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    • 2005
  • The purpose of this study was to establish the upper garment sizing systems for elderly men. These were on the basis of classification of 294 elderly men's somatotypes aged between 60 and 80 with the extent of drop value and analysis of the sizing systems of men's wear companies. The results were as follows: First, the sizing systems of men's wear companies were established with priority given to the young and the middle whose heights were taller than the elderly. There was no sizing system only for elderly men in men's wear companies. Secondly, as the height range increased, the size of chest and waist proportionally increased; however, the waist sizes were limited to somewhat small size ranges. So the sizing systems of men's wear companies had difficulty in covering up the developed-waist somatotype of the elderly. Thirdly, only 1 company out of 10 established the sizing system according to the somatotype. Lastly, the total numbers of size which were established by this study according to somatotype were 40; 18 sizes were set for type A, 10 for type Y, and 12 for type B. The standard sizes were 97-88-165 for type A,94-79-165 for type Y, and 97-94-165 for type B.

임피던스 법을 이용한 두피 상태 추정에 관한 연구 (A Study for Estimation of Scalp Condition by Impedance)

  • 심명헌;최한윤;정인철;김기원;윤형로
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.471-472
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    • 2007
  • The scalp is skin tissue for skull-protection and roots for hair growth. Therefore continuous monitoring of scalp condition is essential for hair management. However, the equipments for existent are inconvenient to use because of focus tremor and external factors(Hair Gel, Wax, accessories and so on). Furthermore there is a problem to use an expensive optical devices like CCD (Charge Coupled Device) camera or lens of 200 - 1000 magnification. It causes a difficulty of using those equipment. We design the special electrode(length 5.65mm, diameter 0.8mm of needle shape) and the impedance system(1kHz, 78uA). Tn this paper, we can measure scalp impedance with our system. Moreover, we find the possibility of classifying scalp condition with measured impedance values. For the classification of scalp condition, we used ARAMO-TS as an imaging system. In conclusion, the problem of existent devices could be improved using these method. It also has a benefit of continuous monitoring of scalp condition.

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뇌졸중 환자의 기능수준에 따른 FIM 신체적 기능 항목의 라쉬분석 (Rasch Analysis of FIM Physical Items in Patients With Stroke in Korea)

  • 박소연;원종임;이미영
    • 한국전문물리치료학회지
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    • 제17권2호
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    • pp.51-59
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    • 2010
  • The Functional Independence Measure (FIM) is widely used to determine the dependency of activity of daily living in rehabilitation patients. The purposes of this study were to evaluate the unidimentionality of the FIM physical items and to analyze the validity of cross-functional levels in stroke survivors in Korea. Thirteen physical items of FIM were rated according to an ordinal scale of a 7-level classification. Two hundred and seventy-nine patients participated in the study (age range 18~92 years and 57% male). Six items-eating, bladder control, bowel control, transfer to and from the bed/wheelchair, transfer to and from the toilet, and bathing-showed misfits with the Rasch model. The most difficult item was 'bathing', the easiest item was 'bowel control'. Although there were several differences within functional levels, the hierarchical order of item measures was rather similar. 'Bathing' was the most difficult in high level patients (above 60), however 'stairs' was most difficult in the middle level (41~60) group. In the low level group (below 40), 'toileting' was the most difficult. In conclusion, the present study has shown several differences of item difficulty among functional levels. This result will be useful in planning interventions, and developing rehabilitation programs for stroke survivors.

하이브리드 신경회로망을 이용한 디지털 단층 영상의 BGA 검사 (Hybrid Neural Network Based BGA Solder Joint Inspection Using Digital Tomosynthesis)

  • 고국원;조형석;김종형;김형철
    • 제어로봇시스템학회논문지
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    • 제7권3호
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    • pp.246-254
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    • 2001
  • In this paper, we described an approach to the automation of visual inspection of BGA solder joint defects of surface mounted components on printed circuit board by using neural network. Inherently, the BGA solder joints are located underneath its own package body, and this induces a difficulty of taking good image of the solder joints by using conventional imaging systems. To acquire the cross-sectional image of BGA sol-der joint, X-ray cross-sectional imaging method such as laminography and digital tomosynthesis has been cur-rently utilized. However, the cross-sectional image obtained by using laminography or DT methods, has inher-ent blurring effect and artifact. This problem has been a major obstacle to extract suitable features for classifi-cation. To solve this problem, a neural network based classification method is proposed int his paper. The per-formance of the proposed approach is tested on numerous samples of printed circuit boards and compared with that of human inspector. Experimental results reveal that the method provides satisfactory perform-ance and practical usefulness in BGA solder joint inspection.

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Identifying potential mergers of globular clusters: a machine-learning approach

  • Pasquato, Mario
    • 천문학회보
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    • 제39권2호
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    • pp.89-89
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    • 2014
  • While the current consensus view holds that galaxy mergers are commonplace, it is sometimes speculated that Globular Clusters (GCs) may also have undergone merging events, possibly resulting in massive objects with a strong metallicity spread such as Omega Centauri. Galaxies are mostly far, unresolved systems whose mergers are most likely wet, resulting in observational as well as modeling difficulties, but GCs are resolved into stars that can be used as discrete dynamical tracers, and their mergers might have been dry, therefore easily simulated with an N-body code. It is however difficult to determine the observational parameters best suited to reveal a history of merging based on the positions and kinematics of GC stars, if evidence of merging is at all observable. To overcome this difficulty, we investigate the applicability of supervised and unsupervised machine learning to the automatic reconstruction of the dynamical history of a stellar system. In particular we test whether statistical clustering methods can classify simulated systems into monolithic versus merger products. We run direct N-body simulations of two identical King-model clusters undergoing a head-on collision resulting in a merged system, and other simulations of isolated King models with the same total number of particles as the merged system. After several relaxation times elapse, we extract a sample of snapshots of the sky-projected positions of particles from each simulation at different dynamical times, and we run a variety of clustering and classification algorithms to classify the snapshots into two subsets in a relevant feature space.

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Human Activity Recognition Based on 3D Residual Dense Network

  • Park, Jin-Ho;Lee, Eung-Joo
    • 한국멀티미디어학회논문지
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    • 제23권12호
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    • pp.1540-1551
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    • 2020
  • Aiming at the problem that the existing human behavior recognition algorithm cannot fully utilize the multi-level spatio-temporal information of the network, a human behavior recognition algorithm based on a dense three-dimensional residual network is proposed. First, the proposed algorithm uses a dense block of three-dimensional residuals as the basic module of the network. The module extracts the hierarchical features of human behavior through densely connected convolutional layers; Secondly, the local feature aggregation adaptive method is used to learn the local dense features of human behavior; Then, the residual connection module is applied to promote the flow of feature information and reduced the difficulty of training; Finally, the multi-layer local feature extraction of the network is realized by cascading multiple three-dimensional residual dense blocks, and use the global feature aggregation adaptive method to learn the features of all network layers to realize human behavior recognition. A large number of experimental results on benchmark datasets KTH show that the recognition rate (top-l accuracy) of the proposed algorithm reaches 93.52%. Compared with the three-dimensional convolutional neural network (C3D) algorithm, it has improved by 3.93 percentage points. The proposed algorithm framework has good robustness and transfer learning ability, and can effectively handle a variety of video behavior recognition tasks.

앨리아싱 조건에서의 광대역 음향신호의 방위각 추정 (Direction of Arrival Estimation under Aliasing Conditions)

  • 윤병우
    • 융합신호처리학회논문지
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    • 제4권3호
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    • pp.1-6
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    • 2003
  • 탱크나 경유자동차 등과 같이 지상에서 이동하는 차량들의 엔진소음은 광대역 특성을 갖고 또한 지형의 다양성 및 표적의 이동으로 인한 다양한 반사 등으로 변화가 심하기 때문에 탐지나 추적이 쉽지 않다 또한 전장 등과 같이 복잡한 환경에서는 배열안테나의 위치 선정 등의 어려움으로 앨리아싱이 일어날 수도 있다. 본 논문에서는 수동 배열 안테나의 성긴 배치로 인한 심각한 공간 앨리아싱 조건하에서 광대역 신호를 방사하는 이동체의 탐지 및 추적 문제에 대해서 연구하였다. 여기서 서브밴드 MUSIC 알고리즘에 근거한 고해상도의 방위각 추정 알고리즘을 개발하였다. 이 것은 공간 앨리아싱으로 인하여 표적의 방위각 추정 값이 변할 때에도 실제의 방위각을 추정할 수 있는 알고리즘이다 결과적으로 이 알고리즘이 성긴 안테나 배치로 인한 공간 앨리아싱 영향을 극복하고 위치 추정을 개선함을 보인다.

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