• Title/Summary/Keyword: Safer design

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Design optimization for analysis of surface integrity and chip morphology in hard turning

  • Dash, Lalatendu;Padhan, Smita;Das, Sudhansu Ranjan
    • Structural Engineering and Mechanics
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    • v.76 no.5
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    • pp.561-578
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    • 2020
  • The present work addresses the surface integrity and chip morphology in finish hard turning of AISI D3 steel under nanofluid assisted minimum quantity lubrication (NFMQL) condition. The surface integrity aspects include microhardness, residual stress, white layer formation, machined surface morphology, and surface roughness. This experimental investigation aims to explore the feasibility of low-cost multilayer (TiCN/Al2O3/TiN) coated carbide tool in hard machining applications and to assess the propitious role of minimum quantity lubrication using graphene nanoparticles enriched eco-friendly radiator coolant based nano-cutting fluid for machinability improvement of hardened steel. Combined approach of central composite design (CCD) - analysis of variance (ANOVA), desirability function analysis, and response surface methodology (RSM) have been subsequently employed for experimental investigation, predictive modelling and optimization of surface roughness. With a motivational philosophy of "Go Green-Think Green-Act Green", the work also deals with economic analysis, and sustainability assessment under environmental-friendly NFMQL condition. Results showed that machining with nanofluid-MQL provided an effective cooling-lubrication strategy, safer and cleaner production, environmental friendliness and assisted to improve sustainability.

A Economic Evaluation for APR+ Standard Design (APR+ 표준설계에 대한 경제성 분석)

  • Ha, Gag-Hyeon;Lee, Jae-Ho
    • Journal of Energy Engineering
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    • v.25 no.1
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    • pp.43-47
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    • 2016
  • KHNP CRI has developed APR+ nuclear power plant since 2007, which is GEN III+ model with 1500 MWe capacity. To develop safer nuclear power plant than APR1400, we investigated advanced design features of ALWR being constructed in Korea and being developed/constructed in foreign countries. We applied the advanced design features and lessons learned from Fukushima accident to develop APR+ standard design suitable for both domestic construction and overseas construction business. One economic assessments have performed during safety design improvement phase(2013.1 ~ 2015.12) of APR+. The result of the economic analysis for APR+ safety inhancement design showed that APR+ N-th plant is about 39.2% more economical than coal-fired 1,000MW power plant. Also APR+ plant is more cost advantage over foreign advanced nation ALWRs.

Optimal Life-Cycle Cost Design of Steel Box Girders (강박스 거더의 생애주기비용 최적설계)

  • Shin Yung-Seok;Park Jang-Ho;Lee Hyun-Sub;Ahn Ye-Jun
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.18 no.4 s.70
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    • pp.445-452
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    • 2005
  • This paper presents a design method to minimize Life Cycle Cost (LCC) of steel box girders. The LCC considered in this paper includes initial cost, expected life-cycle maintenance cost and repair cost. A load carrying capacity curve is derived from a condition grade curve of steel girders and load tarrying capacity that is measured in safety diagnostic test. And then, optimal design of steel box girders is performed on the basis of load carrying capacity curve. In this paper time and number of times for repair of steel girders are determined based on the calculated load carrying capacity curve. Also, annual costs considering real discount rate are compared and analyzed in various cases. It is concluded that the optimal design of steel box gilders considering LCC by the presented method will lead to more economical and safer girders than conventional design.

A Generating Cost Evaluation of APR+ Standard Design (APR+ 표준설계 발전원가 분석)

  • Ha, Gag-Hyeon;Kim, Sung-Hwan;Lee, Jae-Ho
    • Journal of Energy Engineering
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    • v.23 no.4
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    • pp.236-239
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    • 2014
  • KHNP CRI has been developing APR+ nuclear power plant since 2007, which is GEN III+ model with 1500 MWe capacity. To develop safer and more economical nuclear power plant than APR1400, we investigated advanced design features of ALWR(advanced light water reactor) being constructed in Korea and being developed/constructed in foreign countries. We applied the advanced design features and lessons learned from Fukushima accident to develop APR+ standard design suitable for both domestic construction and overseas construction business. Three economic assessments have performed during standard design phase of APR+. The result of the 3th(final) economic analysis for APR+ standard design showed that APR+ N-th plant was about 23% more economical than coal-fired 1,000MW power plant.

A Review of Renal Dialysis Unit Environment for Infection Prevention - Focused on Evidence Based Design (감염 예방을 위한 인공신장실 의료 환경에 대한 고찰 - 근거 기반의 디자인 중심으로)

  • Han, Su Ha;Yoon, Hyungjin
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.24 no.3
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    • pp.49-57
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    • 2018
  • Purpose: The increase in patients requiring hemodialysis has resulted in an increase dialysis-associated infections risk. but there are no Renal Dialysis unit design standard meet specified safety and quality standards. Therefore, appropriate Establish standards and legal regulation is important for the provision of initial certification and maintenance of facility, equipment, and human resource quality. Methods: Literature survey on the design guideline and standards of Renal Dialysis unit design in Korea, U.S, Germany, Singapore, Hongkong, Dubai. Results: There are no established standards for facilities in dialysis units in Korea. To prevent infections in dialysis patients, necessary establish standards. Considering the domestic and overseas Health-care facilities standards, the major factors to be considered in the medical environment for Renal Dialysis Unit are as follows. First, planning to separate Clean areas(treatment area) from contaminated areas(medical waste storage area). Second, ensure sufficient space and minimum separation distance. Although there may be differences depending on the circumstances of individual institutions, renal dialysis unit consider the space to prevent droplet transmission. Third, secure infrastructure of infection prevention such as sufficient amount of hand hygiene sinks. Hand washing facilities for staff within the Unit should be readily available. Hand hygiene sinks should be located to prevent water from splashing into the treatment area. Fourth, Heating, ventilation and air conditioning (HVAC) system for Renal Dialysis Unit is all about providing a safer environment for patients and staff. Implications: The results of this paper can be the basic data for the design of the Renal Dialysis Units and relevant regulations.

A Basic Study on the Improvement of Pedestrian Environment to Reduce Traffic Accidents in Multi-family Housing Complex - Focused on Dongtan 2 New Town in Hwaseong, Gyeonggi Province - (공동주택 단지 내 교통사고 저감을 위한 보행환경 개선에 대한 기초연구 - 경기도 화성시 동탄면 동탄2신도시 사례 중심으로 -)

  • Yoon, Ho-Jung;Yeom, Sung-Jin
    • Journal of Environmental Science International
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    • v.29 no.5
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    • pp.507-517
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    • 2020
  • New towns and large multi-family housing complexes are being built in the capital region of Korea, with the goal of creating safe and pedestrian-friendly cities. Traffic accidents in such residential complexes, however, is on the rise, creating social problems. While there have been many previous studies on problems with pedestrian environment; there is a dearth of studies that take design-based approach to ensure safety in pedestrian environment within residential complexes. Therefore, this study aims to prevent traffic accidents by properly planning pedestrian environment within multi-family housing complexes, in addition to emphasizing theories related to planning safer pedestrian environment in general. This study found the following design directions required to improve the design theory of pedestrian safety in multi-family housing complexes: (1) Linking traffic facilities and residential complex spaces in Korea; (2) Considering implementation of United Kingdom road systems; (3) Establishing appropriate objectives for each residential complex based on case study. In response to these findings, the study selected the A84BL complex in Hwaseong Dongtan 2 Complex located in Dongtan-myeon, Hwaseong-si in Gyeonggi Province, Korea. Items that can be implemented, as well as spatial design directions, were discussed with a focus on private vehicles, pedestrians, and service vehicles.

Inundation Analysis of Agricultural Basin Considering Agricultural Drainage Hydrological Plan and Critical Rainfall Duration (농지배수 수문설계 기준과 임계지속기간을 고려한 농업 소유역 침수분석)

  • Kim, Kwihoon;Jun, Sang-Min;Kang, Moon Seong;Choi, Jin-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.65 no.4
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    • pp.25-32
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    • 2023
  • KDS (Korean Design Standard) for agricultural drainage is a planning standard that helps determine the appropriate capacity and type of drainage facilities. The objective of this study was to analyze the inundation of the agricultural basin considering the current design standard and the critical rainfall duration. This study used the rainfall durations of 1-48 hour, and the time distribution method with the Chicago and the modified Huff model. For the runoff model, the NRCS (Natural Resources Conservation Service) unit hydrograph method was applied, and the inundation depth and duration were analyzed using area-elevation data. From the inundation analysis using the modified Huff method with different rainfall durations, 4 hours showed the largest peak discharge, and 11 hours showed the largest inundation depth. From the comparison analysis with the current method (Chicago method with a duration of 48 hours) and the modified Huff method applying critical rainfall duration, the current method showed less peak discharge and lower inundation depth compared to the modified Huff method. From the simulation of changing values of drainage rate, the duration of 11 hours showed larger inundation depth and duration compared to the duration of 4 hours. Accordingly, the modified Huff method with the critical rainfall duration would likely be a safer design than the current method. Also, a process of choosing a design hydrograph considering the inundation depth and duration is needed to apply the critical rainfall duration. This study is expected to be helpful for the theoretical basis of the agricultural drainage design standards.

An Evaluation of Korean Accessibility Standards Supporting the People with Disabilities (실내환경에서 장애인의 접근.이동성을 지원하는 국내법규 평가)

  • 천진희;정회란
    • Archives of design research
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    • v.12 no.3
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    • pp.167-176
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    • 1999
  • This article analyzed the recent Korean accessibility standard supporting the people with disabilities. This is the basic study to make the interior environment more comprehensible and safer for the physically handicapped. Researcher selected the interior elements related to the mobility and accessibility for the physically handicapped. Then the '98 Korean accessibility standard code called 'Pyunui Chungjin Pup' were compared with the previous Korean building code and two other guidelines for evaluations. Result showed that 'Pyunui Chungjin Pup' addressed more obligatory items in facilities used by people with disabilities. That contributed to develope the accessible environments and to offer the independent activity in the society for the disabilities. However dimensions of 'Pyunui Chungjin Pup' showed the minimum standard. Also it did not provide the sufficient design considerations to make up the sufficient design considerations to make up the other types of disabilities including sensory limitations, or cognitive function limitations. Hereafter, the quality of accessibility guideline should be raised with further study.

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Optimal Design of the Fuel Storage Vessel of CNG Automobile by Considering Structural Efficiency (구조 효율을 고려한 CNG 자동차 연료저장용기의 최적설계)

  • Kim, Ho-Yoon;Bae, Won-Byong;Jang, Young-Jun;Kim, Chul
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.6
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    • pp.465-473
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    • 2008
  • Type II compressed natural gas(CNG) storage vessels for automobiles have been acknowledged for their excellence and have recently become established in local regions. Their supply is not only to automakers in Korea such as Hyundai Motors but they are being increasingly exported. Although the available products have undergone safety evaluations and are certified by an authorized institution they are still short of the optimal design that is possible for such storage vessels. This research investigates the shape and thickness of the dome with the aim of optimizing the type II CNG storage vessels by using a finite element analysis technique. CNG storage vessels can be largely divided into 3 parts namely, the hear part, the cylinder part and the dome part. The head part is designed by means of a hot spinning process and this method is safer than that used in the design of the dome part even though its shape is similar. The thickness of the liners and reinforcing materials was optimized based on the requirements of the cylinder and dome parts. In addition, the shape of the dome, which is most suitable for Type II CNG storage vessels, is proposed by a process of review and analysis of various existing shape, and then conducting a structural stability evaluation to ensure the optimal design plan.

A Study on Comparison and Shortening of Evacuation Time Required of University Library by Simulation (시뮬레이션을 통한 대학도서관의 피난 소요시간 비교 관한 연구)

  • An, Jeong-Pill;Kim, Gwang-Hee
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.16 no.2
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    • pp.10-18
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    • 2017
  • The University library is a reality where facilities can be a massive upset by the space of students to study space and book materials. Also, many print materials can cause fires quickly in fires, resulting in massive amounts of human casualties caused by many toxic gases. This study purpose is compares the time spent in the evacuation of the current state through the simulation, which seeks to derive a reasonable library of evacuation design, and improved inside the evacuation. As a result, the most obvious way to reduce the time required to evacuate is to diversify the evacuation routes and to disperse them. However, if the extension of the gate is not feasible, it is possible to reduce the time of escape by increasing the width of the gate and the width of the stair. If the results of this study are applied to new construction or remodeling of the library and prepare for fire evacuation, it will be a much safer library facility.