• 제목/요약/키워드: study modules

검색결과 2,120건 처리시간 0.025초

ON UNIFORMLY S-ABSOLUTELY PURE MODULES

  • Xiaolei Zhang
    • 대한수학회지
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    • 제60권3호
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    • pp.521-536
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    • 2023
  • Let R be a commutative ring with identity and S a multiplicative subset of R. In this paper, we introduce and study the notions of u-S-pure u-S-exact sequences and uniformly S-absolutely pure modules which extend the classical notions of pure exact sequences and absolutely pure modules. And then we characterize uniformly S-von Neumann regular rings and uniformly S-Noetherian rings using uniformly S-absolutely pure modules.

MODULES THAT SUBMODULES LIE OVER A SUMMAND

  • Min, Kang-Joo
    • 충청수학회지
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    • 제20권4호
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    • pp.569-575
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    • 2007
  • Let M be a nonzero module. M has the property that every submodule of M lies over a direct summand of M. We study some properties of such a module. The endomorphism ring of such a module is also studied. The relationships of such a module to the semi-regular modules, and to the semi-perfect modules are described.

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5kW급 투광형 박막 BIPV시스템의 실증연구 (Case Study on 5kWp Transparent Thin-Film BIPV System)

  • 안영섭;김성태;이성진;송종화;황상근;윤종호
    • 한국태양에너지학회 논문집
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    • 제30권4호
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    • pp.29-35
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    • 2010
  • This study has been carried out empirical research on Transparent Thin-film BIPV modules, BIPV modules installed on the exterior of the building are applied a laminated module 1kWp, double-glazing module 3kWp and triple-glazing module 1kWp. Applied to the total capacity of BIPV modules are 5kWp. In this study, design and construction process of BIPV systems is presented. In addition, through monitoring of the BIPV system, the temperature and the power characteristics of each module were analyzed. During the measurement period, the module temperature measurement results, the maximum surface temperature of $51.5^{\circ}C$ triple-glazing BIPV module showed the highest, followed by double-glazing BIPV module $49.1^{\circ}C$, $44.7^{\circ}C$ laminated modules, respectively. Power output results, the daily average double-layer modules showed 4.10kWh/day, triple-glazing module 1.57kWh, respectively 1.81kWh laminated modules. In particular, the power efficiency of triple-glazing BIPV module was lower than the power efficiency of the laminated BIPV module. This phenomenon is considered to be affected by the module temperature. In the future, BIPV modules in this study the relationship between module temperature and power characteristics plans to identify.

회전식 및 직선식 레이저 모듈 개발에 관한 연구 (A Study on the Development of the Rotary and Linear Laser Modules)

  • 심민섭;황성주;김동현;이춘만
    • 한국정밀공학회지
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    • 제31권2호
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    • pp.119-123
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    • 2014
  • Recently, laser processing technologies have been developed in many different industrial fields. The laser processing technologies are widely being applied such as laser assisted machining, cladding, heat treatment and coating. In the laser modules of the laser assisted machining system, laser lens is very important for accuracy and productivity of product. As the laser beam size, shape and focusing distance change, heat input energy of preheating point can be changed, the laser module of the laser assisted machining system should be equipped with various lenses differing beam size, beam shape and focusing distance. In this study, the rotary and linear laser modules are suggested. The finite element analysis is carried out to certify the static and dynamic stabilities of the developed laser modules. Finally, the rotary and linear laser modules have been fabricated successfully using the analysis results.

A NOTE ON BETTI NUMBERS AND RESOLUTIONS

  • Choi, Sang-Ki
    • 대한수학회논문집
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    • 제12권4호
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    • pp.829-839
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    • 1997
  • We study the Betti numbers, the Bass numbers and the resolution of modules under the change of rings. For modules of finite homological dimension, we study the Euler characteristic of them.

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염료감응형 태양전지를 적용한 유리 패널의 효율 향상에 관한 연구 (A Study on the Efficiency Improvement of Glazing Panel with DSC Modules)

  • 장한빈;강준구;이상길;김준태
    • 한국태양에너지학회 논문집
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    • 제33권2호
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    • pp.35-41
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    • 2013
  • Dye-sensitized solar cell (DSC) allows light transmission and the application of various colors that make it especially suitable for building-integrated PV (BIPV) application. In order to apply DSC module into windows, it has to be panelized: DSC module should be protected with reinforced glass to the entire surface. Up to date, it seems to be common to make double glazing with DSC modules with air gaps between the glasses and the DSC modules. Few research has been conducted on the characteristics of various glazing types with DSC modules. This study aims to analyze the electrical performance of DSC modules according to panelizing method for glazing unit with DSC modules. The prototype of the DSC glazing that applied silicone filler between DSC modules and glasses was developed. The electrical performances of this type of DSC glazing with the filler and rather conventional double glazing with DSC modules were compared. Their performances were measured using a solar simulator that is suitable for DSC performance testing. The results indicated that the electrical performance of the filler type DSC glazing improved by 7% compared to that of the conventional DSC double glazing type.

주거용 건물 태양광발전시스템의 설치유형에 따른 발전성능 평가 (Evaluation of Electricity Generation According to Installation Type of Photovoltaic System in Residential Buildings)

  • 김덕성;김법전;신우철
    • 한국태양에너지학회 논문집
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    • 제37권2호
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    • pp.35-45
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    • 2017
  • The types of installation of the photovoltaic system applied to domestic residential buildings are classified as follows: Mounted modules with air circulation, semi-integrated modules with air duct behind, integrated modules with fully insulated back. In order to study generation characteristics of PV system, we verified the validity of interpretation program based on long-term measurement data of demonstration house installed in BAPV form and also analyzed the generation characteristics and performance of each installation type. The results are as follows. First, the RMSE of amount of generation and simulation according to annual daily insolation of demonstration system located in Daejeon was 0.98kWh and the range of relative error of monthly power generation was -5.8 to 3.1. Second, the average annual PR of mounted modules was 82%, semi-integrated modules 76.1% and integrated modules 71.9%. This differences were attributed to temperature loss. Third, the range of operating temperature of annual hourly photovoltaic modules was -6.5 to $61.0^{\circ}C$ for mounted modules, $-6.0{\sim}73.9^{\circ}C$ for semi-integrated modules and -5.5 to $88.9^{\circ}C$ for integrated modules. The temperature loss of each installation type was -14.0 to 16.1%, -13.8 to 21.9%, and -13.6 to 28.5%, respectively.

"ISO 10303 AP241: Generic model for lifecycle support of AEC facilities"의 시설물관련 요소의 STEP Modularization에 관한 연구 (A Study on the STEP Modularization of Civil Engineering Elements of "ISO 10303 AP241: Generic Model for Lifecycle Support of AEC Facilities")

  • 변수진;안경익;김인한
    • 한국CDE학회논문집
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    • 제12권5호
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    • pp.366-375
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    • 2007
  • Although the STEP modularization is the major development methodology for STEP Application Protocol, there have been few studies on the STEP Modularization in Korea. The necessity of STEP Modularization research has been raised continuously. In addition, the importance became larger and larger because most of newly developing APs, including AP241, are developed using modularization approach. The object of this study is to investigate the basic structure and contents of AEC facilities related Application Modules using STEP Modularization. This study examines 1) the technical analysis regarding STEP Modularization, 2) application modules development regarding civil engineering elements of AP241; Aec_faciliteis_classification", "Aec_civil_item", and "Aec_civil_componet", 3) the developed application modules verification, and 4) the implementation methodology suggestion for application modules and modular AP.