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A Study on the Certification of Miscellaneous Non-Required Electrical Equipment (부가적인 전기 장비품의 인증 방안)

  • Kim, IL-Young;Suh, Jang-Won
    • Journal of Aerospace System Engineering
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    • v.1 no.4
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    • pp.1-6
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    • 2007
  • The interest about the installation and certification for miscellaneous non-required electrical equipment is being increased in the domestic aviation industries. In this paper, the minimum applicable requirements in Airworthiness Standard and the acceptable means of compliance which can be applied to installation and certification for miscellaneous non-required electrical equipment is being researched. As a case study, galley certification procedures are presented by electrical load analysis, installation of warning devices and installation requirements.

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A Study on the Calculation Formulae of Required Air and Burning Gas Amount of Heavy Fuel Oil (중유의 연소에 필요한 소요공기량과 발생가스량의 산식에 관한 연구)

  • 이우환
    • Journal of Advanced Marine Engineering and Technology
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    • v.6 no.1
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    • pp.34-40
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    • 1982
  • The characteristics of typical 17 kinds of fuel oils are studied to fine the calculation formulae for the required amount of air and the combustion gas amount. 1) The author's calculation formulae are as follows; (1) Theoretically required amount of air (2) Theoretical amount of combustion gas 2) Theoretical amount of the required air in combustion and combustion gas of fuel oils are always estimated less with Rosin's formula than with author's one. 3) Theoretical amount of the required air and the amount of combustion gas of fuel oils are more reasonable with author's formula than Rosin's one in comparison with results of actual analysis.

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IFCXML Based Automatic Data Input Approach for Building Energy Performance Analysis

  • Kim, Karam;Yu, Jungho
    • Journal of Construction Engineering and Project Management
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    • v.3 no.1
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    • pp.14-21
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    • 2013
  • To analyze building energy consumption, the building description for building energy performance analysis (BEPA) is required. The required data input for subject building is a basic step in the BEPA process. Since building information modeling (BIM) is applied in the construction industry, the required data for BEPA can be gathered from a single international standard file format like IFCXML. However, in most BEPA processes, since the required data cannot be fully used from the IFCXML file, a building description for BEPA must be created again. This paper proposes IFCXML-based automatic data input approach for BEA. After the required data for BEPA has been defined, automatic data input for BEPA is developed by a prototype system. To evaluate the proposed system, a common BIM file from the BuildingSMART website is applied as a sample model. This system can increase the efficiency and reliability of the BEPA process, since the data input is automatically and efficiently improved by directly using the IFCXML file..

A Development of performance criteria tool for lightweight dry wall (건식경량벽체 요구성능 도출 도구 개발에 관한 연구)

  • Ji, Suk-won;Yoon, Sang-chun;Choi, Soo-kyung
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2019.11a
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    • pp.215-216
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    • 2019
  • The following conclusions were reached through the research on the development of the required performance extraction tools for the application and utilization of various construction methods of lightweght dry wall. 1) Performance required for walls of apartment buildings can be divided into safety, habitation, durability and productivity. Among these, horizontal load resistance, shock resistance, anti-seismic performance, insulation, and acoustic characteristics are the main performance that correspond to dry walls. In addition, safety related to toxic gases and contaminants are required according to recent eco-friendly requirements. 2) To select a wall according to the required performance of an inner wall applied to an apartment, a map tool in the form of 2D matrices was constructed to enable the required performance to be applied, indicating that the wall location and wall material and its differentiating according to the old method.

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IFCXML BASED AUTOMATIC DATA INPUT APPROACH FOR BUILDING ENERGY PERFORMANCE ANALYSIS

  • Ka-Ram Kim;Jung-Ho Yu
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.173-180
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    • 2013
  • To analyze building energy consumption, the building description for building energy performance analysis (BEPA) is required. The required data input for subject building is a basic step in the BEPA process. Since building information modeling (BIM) is applied in the construction industry, the required data for BEPA can be gathered from a single international standard file format like IFCXML. However, in most BEPA processes, since the required data cannot be fully used from the IFCXML file, a building description for BEPA must be created again. This paper proposes IFCXML-based automatic data input approach for BEA. After the required data for BEPA has been defined, automatic data input for BEPA is developed by a prototype system. To evaluate the proposed system, a common BIM file from the BuildingSMART website is applied as a sample model. This system can increase the efficiency and reliability of the BEPA process, since the data input is automatically and efficiently improved by directly using the IFCXML file.

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THE RELATIONSHIP BETWEEN PLOT GEOMETRY AND INPUTS REQUIRED FOR FARM MACHINE OPERATION IN KOREA

  • Singh, Gajendra;Ahn, Duck-Hyun
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.139-147
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    • 1993
  • The rapid industrial growth, the consequent shortage of farm labour and increase in their wage level have facilitated more capitalized agricultural mechanization pattern in Korea. The efficiency of capital intensive machine is highly dependent on farm land structure. This paper describes a model explaining the relationship between farmland structure and required inputs for machine operation and to estimate required inputs for machine operation on the national basis for Korea for its paddy production system. The machine cost is closely related to operation area, but the required labour-hours are more related to machine type adopted . From the technology introduction point of view, if capital intensive machine is introduced, less labour-hours are required but machine kW-hours increase rapidly. From the plot geometry point of view, on good geometry plots, machine kW-hour and labour-hour required are less than that on the poor geometry plots. The kW-jhour per hectare of mechani al energy input id better indicator of mechanization level than kW per hectare or number of machine. If the adopted technology is more capital intensive and plot geometry is good, the cost reduction effect is highly significant.

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A Study on the Required Features of Social Network Service

  • Yoon, Jong-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.7
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    • pp.77-84
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    • 2015
  • The study is to investigate which features are perceived by Social Network Service(SNS) users as the most required one to further boost the usage of service, and to examine the perception of these features of SNS sites varies according to their demographic and service usage characteristics. The study also is to suggest a few of research propositions on the relationships between required features of SNS sites and characteristics of SNS users, based on statistical analyses. To accomplish these research purposes, the study defined characteristics of SNS users including demographic(gender, age) and service usage one(start time of service usage, service usage place), and required features of SNS sites(system, service, information, emotion) based on the literature review of SNS. The results show, based on the statistical analyses using survey questionnaire on Korean and Chinese SNS users, that there are differences in perception of required features of SNS sites among the respondents grouped by age, start time of service usage, service usage place. Finally, the study proposed three research propositions, based on the analysis result, that could be used in SNS related researches in the future.

Estimation of the Number of Sampling Points Required for the Determination of Soil CO2 Efflux in Two Types of Plantation in a Temperate Region

  • Lee, Na-Yeon(Mi-Sun);Koizumi, Hiroshi
    • Journal of Ecology and Environment
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    • v.32 no.2
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    • pp.67-73
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    • 2009
  • Soil $CO_2$ efflux can vary markedly in magnitude over both time and space, and understanding this variation is crucial for the correct measurement of $CO_2$ efflux in ecological studies. Although considerable research has quantified temporal variability in this flux, comparatively little effort has focused on its spatial variability. To account for spatial heterogeneity, we must be able to determine the number of sampling points required to adequately estimate soil $CO_2$ efflux in a target ecosystem. In this paper, we report the results of a study of the number of sampling points required for estimating soil $CO_2$ efflux using a closed-dynamic chamber in young and old Japanese cedar plantations in central Japan. The spatial heterogeneity in soil $CO_2$ efflux was significantly higher in the mature plantation than in the young stand. In the young plantation, 95% of samples of 9 randomly-chosen flux measurements from a population of 16 measurements made using 72-$cm^2$ chambers produced flux estimates within 20% of the full-population mean. In the mature plantation, 20 sampling points are required to achieve means within $\pm$ 20% of the full-population mean (15 measurements) for 95% of the sample dates. Variation in soil temperature and moisture could not explain the observed spatial variation in soil $CO_2$ efflux, even though both parameters are a good predictor of temporal variation in $CO_2$ efflux. Our results and those of previous studies suggest that, on average, approximately 46 sampling points are required to estimate the mean and variance of soil $CO_2$ flux in temperate and boreal forests to a precision of $\pm$ 10% at the 95% confidence level, and 12 points are required to achieve a precision of $\pm$ 20%.

A Investigation and Analysis List of Required Reading for China's Elementary School Students (중국의 초등학생 필독목록 조사 분석)

  • Han, Mi-kyung
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.27 no.3
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    • pp.295-319
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    • 2016
  • This study was conducted to review the reading education and the required reading list for elementary school students which is being executed as part of China's language education. For this purpose, extracurricular reading list of language curriculum standard enacted in 2011 was investigated and required list for elementary school students recommend by China's Ministry of Education education in 2012 and 2015. Furthermore, the comparative analysis of extra curricular reading list and two types of required reading list recommended by the Ministry of Education. As a result of investigation on two types of lists of required reading, it was found out that there are lots of fairy tales and science book types by genre, lots of British book by nation, and as a result of comparison with extra curricular reading list, it was found out that there is higher rate of reflection of oversease books and Chinse authorsd, and that there were higher rate of reflection of contemporary literary works and science. Based on these findings, studies on Chinese authors, Chinese fairy tales, and contemporary literary works and studies and recommendations on various subjects were suggested.

Cooperative Sensing Clustering Game for Efficient Channel Exploitation in Cognitive Radio Network (인지무선 네트워크에서 효율적인 채널 사용을 위한 협력센싱 클러스터링 게임)

  • Jang, Sungjeen;Yun, Heesuk;Bae, Insan;Kim, JaeMoung
    • Journal of Satellite, Information and Communications
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    • v.10 no.1
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    • pp.49-55
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    • 2015
  • In cognitive radio network (CRN), spectrum sensing is an elementary level of technology for non-interfering to licensed user. Required sample number for spectrum sensing is directly related to the throughput of secondary user and makes the tradeoff between the throughput of secondary user and interference to primary user. Required spectrum sensing sample is derived from required false alarm, detection probability and minimum required SNR of primary user (PU). If we make clustering and minimize the required transmission boundary of secondary user (SU), we can relax the required PU SNR for spectrum sensing because the required SNR for PU signal sensing is related to transmission range of SU. Therefore we can achieve efficient throughput of CRN by minimizing spectrum sensing sample. For this, we design the tradeoff between gain and loss could be obtained from clustering, according to the size of cluster members through game theory and simulation results confirm the effectiveness of the proposed method.