• Title/Summary/Keyword: modular analysis

Search Result 606, Processing Time 0.024 seconds

Analysis of Techniques for Carbon Reduction in Residential Construction (주거건축에서의 탄소저감을 위한 기법 분석)

  • Kim, Minsoo;Lee, Taegoo
    • Journal of the Korean Institute of Rural Architecture
    • /
    • v.26 no.2
    • /
    • pp.9-16
    • /
    • 2024
  • In order to achieve carbon neutrality in the architectural field by 2050, this study analyzed the energy impact proportional to CO2 emissions of each technique, such as design methods, the properties of building structures, prefabrication methods, passive houses, and active facilities. In addition, the results were presented quantitatively in terms of carbon reduction, and corresponding housing cases were analyzed. The research method is limited to residential buildings at the Passive House energy level, and carbon reduction techniques and elements in architecture are examined through various literature and materials, and empirical cases are analyzed to determine the specific possibility of realizing carbon reduction in architecture. We want to secure it. Based on these analysis results, it was possible to suggest that it is possible to explore various approaches to carbon reduction in future residential construction. By combining the most efficient techniques according to the energy reduction level or goal setting of the building in question, we expect the possibility of achieving the goal of carbon reduction in the residential sector more realistically.

Failure simulation of nuclear pressure vessel under LBLOCA scenarios

  • Eui-Kyun Park;Jun-Won Park;Yun-Jae Kim;Kukhee Lim;Eung-Soo Kim
    • Nuclear Engineering and Technology
    • /
    • v.56 no.7
    • /
    • pp.2859-2874
    • /
    • 2024
  • This paper presents the finite element deformation and failure simulation of a typical Korean high-power reactor vessel under a severe accident characterized by large break loss of coolant (LBLOCA) with in-vessel retention of molten corium through external reactor vessel cooling (IVR-ERVC) conditions. Temperature distributions calculated using Modular Accident Analysis Program Version 5 (MAAP5) as thermal boundary conditions were used, and ABAQUS thermal and structural analyses were performed. After full ablation, the temperature of the inner surface in the thinnest section remained high (920 ℃), but the stress remained relatively low (less than 6 MPa). At the outer surface, the stress was as high as 250 MPa; however, the resulting plastic strain was small owing to the low temperature of 200 ℃. Variations in stress, inelastic strain, and temperature with time in the thinnest section suggest that the plastic and creep strains are saturated owing to stress relaxation, resulting in low cumulative damage. Thus, the lower head of the vessel can maintain its structural integrity under LBLOCA with IVR-ERVC conditions. The sensitivity analysis of internal pressure indicates the occurrence of failure in the thinnest section at an internal pressure >9.6 MPa via local necking followed by failure due to high stresses.

Development of Web-based Off-site Consequence Analysis Program and its Application for ILRT Extension (격납건물종합누설률시험 주기연장을 위한 웹기반 소외결말분석 프로그램 개발 및 적용)

  • Na, Jang-Hwan;Hwang, Seok-Won;Oh, Ji-Yong
    • Journal of the Korean Society of Safety
    • /
    • v.27 no.5
    • /
    • pp.219-223
    • /
    • 2012
  • For an off-site consequence analysis at nuclear power plant, MELCOR Accident Consequence Code System(MACCS) II code is widely used as a software tool. In this study, the algorithm of web-based off-site consequence analysis program(OSCAP) using the MACCS II code was developed for an Integrated Leak Rate Test (ILRT) interval extension and Level 3 probabilistic safety assessment(PSA), and verification and validation(V&V) of the program was performed. The main input data for the MACCS II code are meteorological, population distribution and source term information. However, it requires lots of time and efforts to generate the main input data for an off-site consequence analysis using the MACCS II code. For example, the meteorological data are collected from each nuclear power site in real time, but the formats of the raw data collected are different from each site. To reduce the efforts and time for risk assessments, the web-based OSCAP has an automatic processing module which converts the format of the raw data collected from each site to the input data format of the MACCS II code. The program also provides an automatic function of converting the latest population data from Statistics Korea, the National Statistical Office, to the population distribution input data format of the MACCS II code. For the source term data, the program includes the release fraction of each source term category resulting from modular accident analysis program(MAAP) code analysis and the core inventory data from ORIGEN. These analysis results of each plant in Korea are stored in a database module of the web-based OSCAP, so the user can select the defaulted source term data of each plant without handling source term input data.

A Study on the Design of Functional Clothing for Vital sign Monitoring -Based on ECG Sensing Clothing- (생체신호 측정을 위한 기능성 의류의 디자인 연구 -심전도 센싱 의류를 중심으로-)

  • Cho, Ha-Kyung;Song, Ha-Young;Cho, Hyeon-Seong;Goo, Su-Min;Lee, Joo-Hyeon
    • Science of Emotion and Sensibility
    • /
    • v.13 no.3
    • /
    • pp.467-474
    • /
    • 2010
  • Recently, Study of functional clothing for Vital sensing is focused on reducing artifact by human motions, in order to enhance the electrocardiogram(ECG) sensing accuracy. In this study, considering the factors for each element found from the analysis, a 3-lead electrode inside textile embroidered with silver yarn was developed, and draft designs off our types of vital-signal sensing garments, which are 'chest-belt typed' garment, 'cross-typed' garment 'x-typed' garment and 'curved x-typed' garment, were prepared. The draft designs were implemented on a sleeveless male shirt made of an elastic material so that the garment and the electrodes can remain closely attached along the contour of the human body, and the acquired data was sent to the main computer over a wireless network. In order to evaluate the effects caused by body movements and the ECG-sensing capability for each type in static and dynamic states, displacements were measured from one and two dimensional perspectives. ECG measurement evaluation was also performed for Signal-to-noise ratio(SNR) analysis. Applying the experimental results, the draft garment designs were modified and complemented to produce two types of modular approaches 'continuous-attached' and 'insertion-detached' for the ECG-sensing smart clothing.

  • PDF

Prestressing Inducing Effect of Continuous Open-top Steel Box Girder Using Modular CFT Members (모듈형 CFT부재를 이용한 개구제형 연속 강박스 거더의 프리스트레싱 도입 효과)

  • Lee, Hak Joon;Kim, Ryeon-Hak;Cho, Kwang-Il;Ahn, Jin-Hee
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.26 no.3
    • /
    • pp.111-119
    • /
    • 2022
  • The increasing sectional stiffness and inducing prestress method of continuous steel box girder using modular CFT members use the restoring force of the CFT module generated from removing the prestressing bars in the CFT module after integrating the prestressed CFT module with the lower steel plate of the steel box girders as a prestressing force. The integrated CFT module in the steel box girder can improve the sectional stiffness of the continuous steel box girder section. To examine the applicability of the introduction of prestressing to the integrated steel box girder using the CFT module, in this study, inducing prestressing tests were conducted using CFT modules for steel plate specimens simulating the lower steel plate of the continuous steel box girder, and FE analyses were conducted for inducing prestressing tests. In addition, to confirm the effect of inducing prestress to the actual steel box girder and increasing sectional stiffness by the CFT modules, FE analyses for the actually applicable continuous steel box section were carried out depending on prestressing force and sectional conditions of the CFT modules, FE analysis results were compared.

Innovative Technology of Teaching Moodle in Higher Pedagogical Education: from Theory to Pactice

  • Iryna, Rodionova;Serhii, Petrenko;Nataliia, Hoha;Kushevska, Natalia;Tetiana, Siroshtan
    • International Journal of Computer Science & Network Security
    • /
    • v.22 no.8
    • /
    • pp.153-162
    • /
    • 2022
  • Relevance. Innovative activities in education should be aimed at ensuring the comprehensive development of the individual and professional development of students. The main idea of modular technology is that the student should learn by himself, and the teacher manages his learning activities. The advantage of modular technology is the ability of the teacher to design the study of the material in the most interesting and accessible forms for this part of the study group and at the same time achieve the best learning results. Innovative Moodle technology. it is gaining popularity every day, significantly expanding the space of teaching and learning, allowing students to study inter-faculty university programs in depth. The purpose of this study is to assess the quality of implementation of the e-learning system Moodle. The study was conducted at the South Ukrainian National Pedagogical University named after K. D. Ushinsky in order to identify barriers to the effective implementation of innovative distance learning technologies Moodle and introduce a new model that will have a positive impact on the development of e-learning. Methodology. The paper used a combination of theoretical and empirical research methods. These include: scientific analysis of sources on this issue, which allowed us to formulate the initial provisions of the study; analysis of the results of students 'educational activities; pedagogical experiment; questionnaires; monitoring of students' activities in practical classes. Results. This article evaluates the implementation of the principles of distance learning in the process of teaching and learning at the University in terms of quality. The experiment involved 1,250 students studying at the South Ukrainian National Pedagogical University named after K. D. Ushinsky. The survey helped to identify the main barriers to the effective implementation of modern distance learning technologies in the educational process of the University: the lack of readiness of teachers and parents, the lack of necessary skills in applying computer systems of online learning, the inability to interact with the teaching staff and teachers, the lack of a sufficient number of academic consultants online. In addition, internal problems are investigated: limited resources, unevenly distributed marketing advantages, inappropriate administrative structure, and lack of innovative physical capabilities. The article allows us to solve these problems by gradually implementing a distance learning model that is suitable for any university, regardless of its specialization. The Moodle-based e-learning system proposed in this paper was designed to eliminate the identified barriers. Models for implementing distance learning in the learning process were built according to the CAPDM methodology, which helps universities and other educational service providers develop and manage world-class online distance learning programs. Prospects for further research focus on evaluating students' knowledge and abilities over the next six months after the introduction of the proposed Moodle-based program.

ANALYSIS OF TMI-2 BENCHMARK PROBLEM USING MAAP4.03 CODE

  • Yoo, Jae-Sik;Suh, Kune-Yull
    • Nuclear Engineering and Technology
    • /
    • v.41 no.7
    • /
    • pp.945-952
    • /
    • 2009
  • The Three Mile Island Unit 2 (TMI-2) accident provides unique full scale data, thus providing opportunities to check the capability of codes to model overall plant behavior and to perform a spectrum of sensitivity and uncertainty calculations. As part of the TMI-2 analysis benchmark exercise sponsored by the Organization for Economic Cooperation and Development Nuclear Energy Agency (OECD NEA), several member countries are continuing to improve their system analysis codes using the TMI-2 data. The Republic of Korea joined this benchmark exercise in November 2005. Seoul National University has analyzed the TMI-2 accident as well as the currently proposed alternative scenario along with a sensitivity study using the Modular Accident Analysis Program Version 4.03 (MAAP4.03) code in collaboration with the Korea Hydro and Nuclear Power Company. Two input files are required to simulate the TMI-2 accident with MAAP4: the parameter file and an input deck. The user inputs various parameters, such as volumes or masses, for each component. The parameter file contains the information on TMI-2 relevant to the plant geometry, system performance, controls, and initial conditions used to perform these benchmark calculations. The input deck defines the operator actions and boundary conditions during the course of the accident. The TMI-2 accident analysis provided good estimates of the accident output data compared with the OECD TMI-2 standard reference. The alternative scenario has proposed the initial event as a loss of main feed water and a small break on the hot leg. Analysis is in progress along with a sensitivity study concerning the break size and elevation.

A Study of SPA Vulnerability on 8-bit Implementation of Ring-LWE Cryptosystem (8 비트 구현 Ring-LWE 암호시스템의 SPA 취약점 연구)

  • Park, Aesun;Won, Yoo-Seung;Han, Dong-Guk
    • Journal of the Korea Institute of Information Security & Cryptology
    • /
    • v.27 no.3
    • /
    • pp.439-448
    • /
    • 2017
  • It is news from nowhere that post-quantum cryptography has side-channel analysis vulnerability. Side-channel analysis attack method and countermeasures for code-based McEliece cryptosystem and lattice-based NTRU cryptosystem have been investigated. Unfortunately, the investigation of the ring-LWE cryptosystem in terms of side-channel analysis is as yet insufficient. In this paper, we propose a chosen ciphertext simple power analysis attack that can be applied when ring-LWE cryptography operates on 8-bit devices. Our proposed attack can recover the key only with [$log_2q$] traces. q is a parameter related to the security level. It is used 7681 and 12289 to match the common 128 and 256-bit security levels, respectively. We identify the vulnerability through experiment that can reveal the secret key in modular add while the ring-LWE decryption performed on real 8-bit devices. We also discuss the attack that uses a similarity measurement method for two vectors to reduce attack time.

The Analysis of the Design Characteristics of Wooden Houses in order to Develop Korean Modern Wooden Houses (한국형 중목구조 주택 표준화 개발을 위한 목조주택의 디자인 특성 분석)

  • Lee, Jusuk
    • Journal of the Society of Disaster Information
    • /
    • v.13 no.4
    • /
    • pp.537-549
    • /
    • 2017
  • Wooden houses are classified into Traditional, Modern, Platform, Timber framing types. The most popular type is Platform framing which is come from foreign culture. The foreign and Korean tree structure tend to be incompatible with Korean culture and don't fit well with modern lifestyle. In this study, it will analyze the design characteristics of the traditional and modern wooden house to solve these problems. The design characteristics will be contributed to the development of wooden architecture which is suitable for Korean architectural style and lifestyle The research consists of space analysis, plane analysis, structural system analysis, roof type analysis, and aesthetic analysis. From the analytical results the design characteristics of traditional Hanok and modern wood structure, we propose the modular elements and the inner and outer shapes of the Korean - style wooden house.

Analysis of the variability of deflection of a prestressed composite bridge deck

  • Staquet, Stephanie;Detandt, Henri;Espion, Bernard
    • Steel and Composite Structures
    • /
    • v.4 no.5
    • /
    • pp.385-402
    • /
    • 2004
  • Nearly 400 composite railway bridge decks of a new kind belonging to the trough type with U-shaped cross section have been constructed in Belgium over the last fifteen years. The construction of these bridge decks is rather complex with the preflexion of precambered steel girders, the prestressing of a concrete slab and the addition of a 2nd phase concrete. Until now, they have been designed with a classical computation method using a pseudo-elastic analysis with modular ratios. Globally, they perform according to the expectations but variability has been observed between the measured and the computed camber of these bridge decks just after the transfer of prestressing and also at long-term. A statistical analysis of the variability of the relative difference between the measured camber and the computed camber is made for a sample of 36 bridge decks using no less than 10 variables. The most significant variables to explain this variability at prestressing are the ratio between the maximum tensile stress reached in the steel girders during the preflexion and the yield strength and the type of steel girder. For the same sample, the long-term camber under permanent loading is computed by two methods and compared with measurements taken one or two years after the construction. The camber computed by the step-by-step method shows a better agreement with the measured camber than the camber computed by the classical method. The purpose of the paper is to report on the statistical analysis which was used to determine the most significant parameters to consider in the modeling in order to improve the prediction of the behaviour of these composite railway bridge decks.