• 제목/요약/키워드: minimal weight

검색결과 259건 처리시간 0.021초

바닥충격음의 등급화 시공방안 (A Working plan of classification against Floor Impact Sound)

  • 정갑철
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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    • pp.170-173
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    • 2004
  • 2004년 4월 23일부터 바닥충격음에 대한 법이 시행되어 신규설계에 반영되고 있다. 새롭게 제시된 법에 따르면 표준 바닥구조를 통해 최소 슬래브 두께가 180 mm로 제시되었으며 중량충격음에 대한 최소 기준도 함께 제시되었다. 또한 최소기준과는 별도로 경량 충격음에 대한 등급화가 제시되어 소비자의 요구를 수용할 수 있도록 하였다. 그러나 현장 시험을 통한 조사 결과 경량 충격음의 등급화 시공을 위한 방안이 제시되지 않음으로서 설계목표를 세우고도 이루지 못하는 문제가 예상되고 있다. 본 내용은 등급화 시공을 위해서 검토해야 할 내용을 정리하여 설계자와 건설사에 도움을 주고자 한 내용이다.

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Optimization of structural elements of transport vehicles in order to reduce weight and fuel consumption

  • Kovacs, Gyorgy
    • Structural Engineering and Mechanics
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    • 제71권3호
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    • pp.283-290
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    • 2019
  • In global competition manufacturing companies have to produce modern, new constructions from advanced materials in order to increase competitiveness. The aim of my research was to develop a new composite cellular plate structure, which can be primarily used for structural elements of road, rail, water and air transport vehicles (e.g. vehicle bodies, ship floors). The new structure is novel and innovative, because all materials of the components of the newly developed structure are composites (laminated Carbon Fiber Reinforced Plastic (CFRP) deck plates with pultruded Glass Fiber Reinforced Plastic (GFRP) stiffeners), furthermore combines the characteristics of sandwich and cellular plate structures. The material of the structure is much more advantageous than traditional steel materials, due mainly to its low density, resulting in weight savings, causing lower fuel consumption and less environmental damage. In the study the optimal construction of a given geometry of a structural element of a road truck trailer body was defined by single- and multi-objective optimization (minimal cost and weight). During the single-objective optimization the Flexible Tolerance Optimization method, while during the multi-objective optimization the Particle Swarm Optimization method were used. Seven design constraints were considered: maximum deflection of the structure, buckling of the composite plates, buckling of the stiffeners, stress in the composite plates, stress in the stiffeners, eigenfrequency of the structure, size constraint for design variables. It was confirmed that the developed structure can be used principally as structural elements of transport vehicles and unit load devices (containers) and can be applied also in building construction.

CONSTRUCTION OF TWO- OR THREE-WEIGHT BINARY LINEAR CODES FROM VASIL'EV CODES

  • Hyun, Jong Yoon;Kim, Jaeseon
    • 대한수학회지
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    • 제58권1호
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    • pp.29-44
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    • 2021
  • The set D of column vectors of a generator matrix of a linear code is called a defining set of the linear code. In this paper we consider the problem of constructing few-weight (mainly two- or three-weight) linear codes from defining sets. It can be easily seen that we obtain an one-weight code when we take a defining set to be the nonzero codewords of a linear code. Therefore we have to choose a defining set from a non-linear code to obtain two- or three-weight codes, and we face the problem that the constructed code contains many weights. To overcome this difficulty, we employ the linear codes of the following form: Let D be a subset of ��2n, and W (resp. V ) be a subspace of ��2 (resp. ��2n). We define the linear code ��D(W; V ) with defining set D and restricted to W, V by $${\mathcal{C}}_D(W;V )=\{(s+u{\cdot}x)_{x{\in}D^{\ast}}|s{\in}W,u{\in}V\}$$. We obtain two- or three-weight codes by taking D to be a Vasil'ev code of length n = 2m - 1(m ≥ 3) and a suitable choices of W. We do the same job for D being the complement of a Vasil'ev code. The constructed few-weight codes share some nice properties. Some of them are optimal in the sense that they attain either the Griesmer bound or the Grey-Rankin bound. Most of them are minimal codes which, in turn, have an application in secret sharing schemes. Finally we obtain an infinite family of minimal codes for which the sufficient condition of Ashikhmin and Barg does not hold.

극소 부호의 새로운 확장 기법 (A New Extension Method for Minimal Codes)

  • 정진호
    • 전기전자학회논문지
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    • 제26권3호
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    • pp.506-509
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    • 2022
  • 비밀 공유 기법에서는 비밀 정보가 사용자들에게 분산되어 저장되고, 특정 허가된 사용자의 부분 집합으로부터만 비밀이 재합성될 수 있어야 한다. 이를 위해서는 서로 다른 부호어들 사이의 정보가 종속되지 않아야 한다. 극소 부호는 선형 블록 부호의 일종으로서 이러한 비밀 정보들이 상호 종속되지 않게 분산하는 역할을 한다. 본 논문에서는 극소 부호의 새로운 확장 기법을 제시한다. 임의의 벡터와 극소 부호의 곱을 통해 새로운 길이와 해밍 무게를 가지는 새로운 극소 부호가 생성된다. 이를 통해 기존에 알려지지 않은 파라미터를 가지는 극소 부호들을 제공할 수 있다.

고구마 무병묘의 기내 증식에 미치는 생장조절물질, Sucrose, 최소생장 보존의 영향 (Effect of Growth Regulator, Sucrose, and Minimal-growth Conservation on In Vitro Propagation of Virus-free Sweet Potato Plantlets)

  • 이나라;이승엽
    • 생물환경조절학회지
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    • 제29권1호
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    • pp.1-8
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    • 2020
  • 고구마 바이러스 무병묘의 기내급속증식을 위한 적정 생장 조절물질 및 sucrose 농도, 최소생장 기내보존(15℃)에 미치는 광의 영향과 생존율 및 기내생장 특성 등을 조사하였다. 고구마 무병묘의 마디배양은 0.2 mg·L-1 BA 첨가배지에서 줄기신장, 줄기직경, 잎수, 뿌리수, 생체중 및 건물중 등이 가장 양호하였다. 배양부위 및 배지물리성에 따른 적정 sucrose 농도는 마디배양은 5% sucrose를 첨가한 고체배지에서, 정단배양은 3% sucrose를 첨가한 액체배지에서 줄기두께, 잎수, 뿌리수, 뿌리길이, 생체중 및 건물중 등의 생육에 가장 효과적이었다. 15℃ 저온항온기에서 고구마 무병묘의 최소생장 기내보존은 암상태에서는 3개월 내에 모두 고사하였으나, 적색:청색(7:3) 혼합 LED (150±5 μmol·m-2·s-1 PPFD)에서는 5개월까지 100% 생존하였다. 따라서 고구마 무병묘의 최소생장 기내보존에는 광이 필요하며, 샬레에 밀식(10 개체/샬레)할 경우, 좁은 공간에서 대량보존이 가능하였다.

Changes of plasma melatonin level and testis weight in the seasonal light-period

  • Han, Sang-Zin
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 2003년도 춘계학술대회
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    • pp.160-160
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    • 2003
  • Plasma melatonin in the seasonal light-period is circadian rhythmically secreted. Maximal secretion showed at 14 o'clock in summer- and winter-like period, but minimal secretion showed at 5 o'clock in summer-like period and at 8 in winter-like period. These times of minimal secretions were at the beginning of light period. Plasma melatonin in the light period is secreted 62.5% more than in the dark period in summer-like period and 45.9% more in winter-like period. Total plasma melatonin in winter-like period is secreted 56.5% more than in summer-like period. The weights of testis(-20.8%) and body(-7.1%) were reduced in the winter-like period. By the increase of plasma melatonin in mice, body- and testis-weights are decreased, on the contrary by the decrease of plasma melatonin in mice, body and testis weights are increased. In view of the results so far achieved melatonin changes on the body weight and reproductive organ in mice. It is presumed that melatonin effects on the metabolism and sex hormone.

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인위적인 계절적 광주기에서 쥐에 나타나는 멜라토닌 분비양상과 정소크기변화 조사 (Changes of Plasma Melatonin Level and Testis Weight in Mice in the Seasonal Light-period)

  • 한상진
    • Environmental Analysis Health and Toxicology
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    • 제18권1호
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    • pp.57-61
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    • 2003
  • Plasma melatonin in the seasonal light-period is circadian rhythmically secreted. Maximal secretion showed at 14 o'clock in summer- and winter-like period, but minimal secretion showed at 5 o'clock in summer-like period and at 8 in winter-like period. These times of minimal secretions were at the beginning of light period. Plasma melatonin in the light period is secreted 62.5% more than in the dark period in summer- like period and 45.9% more in winter- like period. Total plasma melatonin in winter-like period is secreted 56.5% more than in summer-like period. The weights of testis (-20.8%) and body (-7.1%) were reduced in the winter-like period. By the increase of plasma melatonin in mice, body - and testis -weights are decreased, on the contrary by the decrease of plasma melatonin in mice, body and testis weights are increased. In view of the results so far achieved melatonin changes on the body weight and reproductive organ in mice. It is presumed that melatonin effects on the metabolism and sex hormone.

한국 여성의 초경개시 임계 체중과 체지방률 (Minimal Weight and Body Fat Percentage in Relation to the Onset of Menarche in Korean Females)

  • 정은숙;이정아;임현숙
    • 대한지역사회영양학회지
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    • 제10권2호
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    • pp.196-204
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    • 2005
  • Menarche is a main indicator of sexual maturity which relates to a reproductive function. The onset of the menstrual cycle differs individually and is influenced by many variables such as socio-economic situation, race, genetics, climate, altitude, nutritional status, and physical growth. Among them physical growth has been known to be the most influencing factor, particularly when expressed as body fat designated by weight. This study intended to investigate the body composition of girls around the menarche period and to evaluate the minimal levels of weight and fat percentage needed for the onset of menarche. A total of 101 female subjects, aged 11 to 13 years, were recruited from the 5th and 6th grades of an elementary school, in Mokpo, Korea. The subjects were placed into one of two groups Pre-menarche and Post-menarche groups according to their experience with menarche. Thereafter, the subjects in the Post-group were placed into 4 subgroups based on the number of menstruations they experienced: Post-I (1-3 times), Post-II (4-6 times), Post-III (7-9 times), and Post-IV (> 10 times). The average age at the onset of menarche of the subjects in Post groups was $11.2 \pm 0.6$ years. There were significant differences in the data of anthropometry and body composition between the Pre and Post groups, although the mean ages of both Pre and Post groups were the same. Weight, waist, hip and thigh girths, fat percentage, and lean body mass of the Post groups were significantly higher than those of the Pre group. Height was not significantly different between the groups. Weight was highly correlated with body fat mass (r = 0.92. p < 0.001), fat percentage (r = 0.85, p < 0.001), and body mass index (r = 0.91, p < 0.001) These results indicate that weight, compared with height, reflects body composition well and influences the onset of the menstrual cycle. It could also be suggested that the minimal weight and fat percentage needed for the onset of menarche in Korean females are 41 kg and $17\%\;to\;19\%$, respectively.

PRIMITIVE IDEMPOTENTS IN THE RING F4[x]/〈xpn-1〉 AND CYCLOTOMIC Q CODES

  • Batra, Sudhir;Mathur, Rekha
    • 대한수학회보
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    • 제55권3호
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    • pp.971-997
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    • 2018
  • The parity of cyclotomic numbers of order 2, 4 and 6 associated with 4-cyclotomic cosets modulo an odd prime p are obtained. Hence the explicit expressions of primitive idempotents of minimal cyclic codes of length $p^n$, $n{\geq}1$ over the quaternary field $F_4$ are obtained. These codes are observed to be subcodes of Q codes of length $p^n$. Some orthogonal properties of these subcodes are discussed. The minimal cyclic codes of length 17 and 43 are also discussed and it is observed that the minimal cyclic codes of length 17 are two weight codes. Further, it is shown that a Q code of prime length is always cyclotomic like a binary duadic code and it seems that there are infinitely many prime lengths for which cyclotomic Q codes of order 6 exist.

Design of Block Codes for Distributed Learning in VR/AR Transmission

  • Seo-Hee Hwang;Si-Yeon Pak;Jin-Ho Chung;Daehwan Kim;Yongwan Kim
    • Journal of information and communication convergence engineering
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    • 제21권4호
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    • pp.300-305
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    • 2023
  • Audience reactions in response to remote virtual performances must be compressed before being transmitted to the server. The server, which aggregates these data for group insights, requires a distribution code for the transfer. Recently, distributed learning algorithms such as federated learning have gained attention as alternatives that satisfy both the information security and efficiency requirements. In distributed learning, no individual user has access to complete information, and the objective is to achieve a learning effect similar to that achieved with the entire information. It is therefore important to distribute interdependent information among users and subsequently aggregate this information following training. In this paper, we present a new extension technique for minimal code that allows a new minimal code with a different length and Hamming weight to be generated through the product of any vector and a given minimal code. Thus, the proposed technique can generate minimal codes with previously unknown parameters. We also present a scenario wherein these combined methods can be applied.