• Title/Summary/Keyword: standard size

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An experimental study on the performance of inverter heat pump with a variation of frequency and capillary size (인버터 열펌프의 주파수 및 모세관 길이 변화에 따른 시스템 성능특성의 실험적 연구)

  • Choi, J.M.;Kim, Y.C.;Kim, J.Y.;Bae, Y.D.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.9 no.1
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    • pp.64-72
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    • 1997
  • An experiment study was performed to investigate the optimum cycle of an inverter heat pump as a function of frequency. The performance of the inverter heat pump with the rated cooling capacity of 4141W(3550kcal/h) was measured with a variation of frequency, indoor and outdoor temperature, and length of capillary tube in the psychrometric test room. As a base case, the inverter heat pump with the standard capillary length of 1000mm which was optimum size for the frequency of 60Hz and ARHRAE Test condition A was tested by varying frequency from 30Hz to 80Hz. Then, the optimum cycle was invesigated by varying the length of capillary tube at each frequency levels of 30, 60 and 80Hz. Based on the experimental data, the change of system characteristics between the optimum and the base case were analyzed for each selected frequency levels. Generally, for low frequency level(30Hz), the longer length of the capillary tube compared with the standard size showed the higher EER, while for high frequency level(80Hz) the shorter length of the capillary tube showed the higher EER.

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Practical Silicon-Surface-Protection Method using Metal Layer

  • Yi, Kyungsuk;Park, Minsu;Kim, Seungjoo
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.4
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    • pp.470-480
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    • 2016
  • The reversal of a silicon chip to find out its security structure is common and possible at the present time. Thanks to reversing, it is possible to use a probing attack to obtain useful information such as personal information or a cryptographic key. For this reason, security-related blocks such as DES (Data Encryption Standard), AES (Advanced Encryption Standard), and RSA (Rivest Shamir Adleman) engines should be located in the lower layer of the chip to guard against a probing attack; in this regard, the addition of a silicon-surface-protection layer onto the chip surface is a crucial protective measure. But, for manufacturers, the implementation of an additional silicon layer is burdensome, because the addition of just one layer to a chip significantly increases the overall production cost; furthermore, the chip size is increased due to the bulk of the secure logic part and routing area of the silicon protection layer. To resolve this issue, this paper proposes a practical silicon-surface-protection method using a metal layer that increases the security level of the chip while minimizing its size and cost. The proposed method uses a shift register for the alternation and variation of the metal-layer data, and the inter-connection area is removed to minimize the size and cost of the chip in a more extensive manner than related methods.

A Scheme to Optimize Q-Algorithm for Fast Tag Identification (고속 태그 식별을 위한 Q-알고리즘 최적화 방안)

  • Lim, In-Taek
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.12
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    • pp.2541-2546
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    • 2009
  • In the anti-collision scheme proposed by EPCglobal Class-1 Gen-2 standard, the frame size for a query round is determined by Q-algorithm. In the Q-algorithm, the reader calculates a frame size without estimating the number of tags in it's identification range. It uses only the slot status. Therefore, the Q-algorithm has advantage that the reader's algorithm is simpler than other DFSA algorithms. However, the standard does not define an optimized parameter value for adjusting the frame size. In this paper, we propose the optimized parameter values for minimizing the identification time by various computer simulations.

A Study on the Current Shroud(II) (현행수의에 관한 연구(II))

  • 유관순
    • Journal of the Korean Society of Costume
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    • v.30
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    • pp.101-116
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    • 1996
  • The purpose of this study is to investigate the actual conditions of current shroud. People began preparing their shroud after their 60th birthday anniversary. To keep the prepared shroud unharmed mothballs leaf tobacco and kungkungi were placed inside. The size was larger than everyday clothes. The size of the men's shroud was 390 Ch'ok and that of the women's shroud was 330 Ch'ok in formal funeral ceremonies. But size would be determined by the person's standard of living or economic situation. According to the proposed size of shroud illustrated in table 10 and the size was 5 to 30cm larger than every-day clothes. The shape of the shroud was various that Ryomp'o represented by the cross and so on.

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A study on the development of global standardized size for souvenir T-shirts (관광문화상품 티셔츠의 치수체계 조사 및 치수표기법 제안)

  • Lee, Hyun-Hwa;Nam, Yun-Ja;Choi, Young-Lim
    • Fashion & Textile Research Journal
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    • v.11 no.2
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    • pp.293-300
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    • 2009
  • Customers purchasing souvenir T-shirts in famous tourist sites in Korea are mainly foreigners. Nevertheless, these T-shirts are manufactures according to Koreans' body shapes or manufactures' own size system. Moreover, sizes are labelled only by domestic norms. The purpose of this study is to suggest global standardized size for T-shirts, which will provide more precise size information for customers. For this, sizing standards including KS, ASTM, JIS, and EN were surveyed and were compared. And souvenir T-shirts were collected in the tourist resort and the sizing systems and labels were analysed from them. Finally, we proposed a sizing system and labelling as an international standard for souvenir T-shirts.

Design of the Open-Loop Combined Meandered-Line 1-Layer Radiator for Diversity Antennas with Size-Reduction and Improved Isolation (다이버시티 안테나의 소형화와 격리도 향상을 위한 미앤더 선로와 개방형 루프가 결합된 방사구조의 설계)

  • Mok, Se-Gyoon;Kahng, Sung-Tek;Kim, Yong-Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.61 no.1
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    • pp.110-116
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    • 2012
  • This paper proposes a new diversity antenna which is the base of MIMO, tunable and reconfigurable antennas. The antenna has a small size and high inter-antenna isolation resulting from the compact radiating element comprising a meandered line and an open-loop combined in one limited uniplanar space and a modified T-shaped decoupling structure, respectively. In a WiMAX band, the radiating element and the entire antenna are $0.092{\lambda}$ and $0.2216{\lambda}$ in size, which shows effective size-reduction and the gain and efficiency of the proposed antenna attached to the ground of a handheld device are 3.7dBi and 56% acceptable to the industrial standard.

A Research of Body Size Analysis and Graphing in 20yrs Korean Women (20대 한국 여성의 체위 분석과 도식화 연구)

  • Kim, Dong-Il;Park, Hyun-Jung
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.1
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    • pp.179-198
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    • 2008
  • Purpose: Obesity is already a major clinical problem in Korea, so obesity prevention and treatment practices are gradually interested in Korean Medicine doctors. Moreover subjective body shape image entered as a important medical topic recently. To make a graph system for clinical tool which based on the Korean national standard physical scale. Methods: Physical data of the girth of upper arm, abdomen, hip, buttock, flank, calf, and body weight were statistically analyzed, which collected through the fifth national standard physical scale research. And then reviewed those statistical validation. Results: Relationship of the each body scale data and those graphs were fit and right statistically. Conclusion: These new achieved graph system of Korean standard body scales could be adopt as a useful clinical tool for body image related patients such as obesity, PCOD and postpartum patient.

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A Study on the Standard Sizes Selection Method for Combat Fatiques Using a Clustering Algorithm of Neural Networks (Neural Networks Clustering Algorithm을 이용한 전투복 표준호수 선정에 관한 연구)

  • 김충영;심정훈
    • Korean Management Science Review
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    • v.16 no.1
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    • pp.89-99
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    • 1999
  • Combat fatigues are issued to military personnel with ready made clothes. Ready made combat fatigues should be fitted to various bodies of military personnel within given standard size. This paper develops a standard sizes selection method in order to increase the coverage rate and fitness for combat fatigues. The method utilizes a generalized learning vector quantization(GLVQ) algorithm that is one of cluster algorithm in neural networks techniques. The GLVQ moves the standard sizes from initial arbitrary sizes to next sizes in order to increase more coverage rate and fitness. Finally, when it cannot increase those, algorithm is terminated. The results of this method show more coverage rate and fitness than those of the other methods.

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Development and its Validation of Sky Simulator Facilities for Daylighting Evaluation (자연채광 성능평가용 인공천공돔(Sky Simulator)의 개발 및 신뢰성 검증)

  • Kim, Jeong-Tai;Kim, Gon;Yu, In-Hye
    • KIEAE Journal
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    • v.5 no.4
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    • pp.51-57
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    • 2005
  • For the evaluating daylighting performance, field measurement, scale model test and a set of computer tools can be applied. For the scale model measurements, the sky simulator is a vital facility to represent the desired sky conditions consistently. Recently K university has developed a large size sky simulator, 6m-diameter and 3.7m-height, that is suitable for the international standard. To verify the reliability of the sky simulator, the luminance distribution on the inner sky surface was measured and compared with the CIE standard overcast sky model. It is found that the sky simulator can be reproduced the CIE standard overcast sky condition with 4.3% as mean difference. K university sky simulator is fully validated for usability and accuracy for daylighting researches.