• Title/Summary/Keyword: Safe life design

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Prediction and optimization of thinning in automotive sealing cover using Genetic Algorithm

  • Kakandikar, Ganesh M.;Nandedkar, Vilas M.
    • Journal of Computational Design and Engineering
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    • v.3 no.1
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    • pp.63-70
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    • 2016
  • Deep drawing is a forming process in which a blank of sheet metal is radially drawn into a forming die by the mechanical action of a punch and converted to required shape. Deep drawing involves complex material flow conditions and force distributions. Radial drawing stresses and tangential compressive stresses are induced in flange region due to the material retention property. These compressive stresses result in wrinkling phenomenon in flange region. Normally blank holder is applied for restricting wrinkles. Tensile stresses in radial direction initiate thinning in the wall region of cup. The thinning results into cracking or fracture. The finite element method is widely applied worldwide to simulate the deep drawing process. For real-life simulations of deep drawing process an accurate numerical model, as well as an accurate description of material behavior and contact conditions, is necessary. The finite element method is a powerful tool to predict material thinning deformations before prototypes are made. The proposed innovative methodology combines two techniques for prediction and optimization of thinning in automotive sealing cover. Taguchi design of experiments and analysis of variance has been applied to analyze the influencing process parameters on Thinning. Mathematical relations have been developed to correlate input process parameters and Thinning. Optimization problem has been formulated for thinning and Genetic Algorithm has been applied for optimization. Experimental validation of results proves the applicability of newly proposed approach. The optimized component when manufactured is observed to be safe, no thinning or fracture is observed.

Calculation of Maximum Allowabel Temperature Difference for Life Design of Valve Casings for Steam Turbines of Fossil Power Plants (화력발전용 증기터빈 밸브 케이싱의 수명 설계를 위한 최대허용온도차 계산)

  • Ha, Joon-Wook;Kim, Tae-Woan;Lee, Boo-Youn
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.8
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    • pp.46-52
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    • 1999
  • Large valves for steam turbines of fossil power plants are exposed to a severe mechanical and thermal loading resulting from steam with high pressure and high temperature. Valve casings are designed to withstand such a loading. During the operation of a plant, temperatures at inner and outer surface of the casings are measured and steam flow is controlled so that the measured difference is lower than the maximum allowable value determined in the design stage. In this paper, a method is presented to calculate the maximum allowable temperature difference at the inner and outer surface of valve casings for steam turbines of fossil power plants. The finite element method is used to analyze distribution of temperature and stresses of a casing under the operating condition. Low cycle fatigue and creep rupture are taken into consideration to determine the maximum allowable temperature difference. The method can be usefully applied in the design stage of the large valves for the steam turbines, contributing to safe and reliable operation of the fossil power plants.

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The Development of Safety and Functional Snowboard Wear Design - Focus on the Safety Snowboard Pants for the Protection of Hip -

  • Kim, Mun Young
    • Fashion & Textile Research Journal
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    • v.15 no.3
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    • pp.364-370
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    • 2013
  • This research helps secure the safety of snow boarders in an activity that is currently recognized as a minor specific hobby. The research goal is to develop a new board wear product with intensified safety and activity through the development of a safe and convenient snowboard wear that is wearable in ordinary life. The participants consisted of 31 snowboard club members evaluated from January 12 to January 19 at Eden-valley Ski Resort and Phoenix-park Resort in Korea. The result are as follows. First, what domestic snowboard wear consumers consider design difference and brand recognition a significant priority in choosing snowboard wear versus the functionality or safety of clothes. Second, concerning the evaluation of the developed product, they recognize the necessity of safety gear; however, they demand the convenient use of a safety gear with a fixation that can be attached and detached. A unity-type board wear was developed that enables an attachment and detachment that reflects the evaluation results. In conclusion, this research showed various market possibility of board wear into sports casual wear to be able to make it a fashion product through different design and demand of mixing it with general wear rather than functionality or activity, though board wear is a professional sports wear.

Effect of the Tai Chi Exercise Program on Physical Function, Cognitive Function, and Quality of Life among Older Adults in the Community: A Preliminary Study (타이치운동 프로그램이 지역사회 거주 노인의 신체기능, 인지기능 및 삶의 질에 미치는 효과: 인지기능을 중심으로-예비조사 연구)

  • Song, Rhayun;Jang, Taejeong
    • Journal of Korean Academic Society of Home Health Care Nursing
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    • v.30 no.3
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    • pp.252-263
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    • 2023
  • Purpose: To assess the feasibility, safety, and preliminary estimates of effectiveness of Tai Chi on the functional outcomes of older adults in the community. Methods: This was a mixed-method study that employed a single-group repeated measure design and in-depth interviews. Nine older adults were recruited from the community were recruited to participate in a Tai Chi program, conducted twice weekly for 6 months. Research outcomes included physical function, cognitive function, and quality of life, measured at intervals of 3 and 6 months. Findings: Tai Chi exercises were gradually conducted based on the health status of the older adults. All participants actively participated in the program with an average attendance of 90%. Consequently, the participants showed significant improvements in mobility and their memory recall ability at both 3 and 6 months. Additionally, the results of the Stroop test exhibited improvement 3 months after the commencement of the study program. Quality of life of the participants improved according to the mild cognitive impairment questionnaire, but it did not show significant improvement in health-related quality of life. Conclusion: The Tai Chi exercise program was a safe and, feasible program to improve the physical function, cognitive function, quality of life among the older adults in the community.

Study on the Convergent Life Evaluation due to the Bumper Configuration of Multipurpose Vehicle (다목적차량의 범퍼형상에 따른 융합적 수명평가에 관한 연구)

  • Lee, Jung-Ho;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.6 no.5
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    • pp.85-90
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    • 2015
  • In this study, the life evaluation due to the structural configuration of bumper attached at the front side of ATV vehicle is studied on the basis of fatigue analysis. As the purpose of this study, the characteristic of bumper exposed on the repetitive loading condition like the vibration is understood. The position of crack happened at the fatigue situation is grasped in advance and complemented in advance. It is considered that the multipurpose vehicle is designed to not be driven on the paved general road but the rough road like the unpaved load. And the weak part of bumper is understood through the study of life evaluation on this driving environment. The durability can be improved by doing the safe design of automotive bumper on the basis of the analysis result. And it is possible to be grafted onto the convergence technique at design and show the esthetic sense.

A Study on Required Safe Egress Time (RSET) Comparison and Error Calculation in Relation to Fire Room Range Set Conditions of Performance Based Fire Safety Designers (성능위주설계자들의 화재실 범위 설정 방식에 따른 소요피난안전시간(RSET) 비교 및 오차산정에 관한 연구)

  • Baek, Sona;Choi, Jun-Ho;Hong, Won-Hwa;Jung, Jong-Jin
    • Fire Science and Engineering
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    • v.30 no.3
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    • pp.73-78
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    • 2016
  • The Installation, Maintence, and Safety Control of Fire-fighting Systems Act of South Korea regulates that over 30-storey high-rise buildings including underground spaces should vitally perform the Performance-based Design to minimize property damage and personal injury as a fire risk assessment in advance. Therefore a PBD designer such as a fire safety professional engineer evaluate occupant's life safety by a scientific methodology. In order to evaluate the life safety, fire safety designers calculate the Required Safety Egress Time (RSET) which does not have the legal criteria regarding the standard method of calculation yet. So this way has been showing different results depending upon the designer's choice, knowledges and experiences. In this study, RSET calculation methods by six designers respectively were analysed from the thirteen reports of real performance based design projects conducted in Busan for a last five years. In particular, the Response Time calculation methods which have the most powerful effect for figuring the RSET are compared with the other designer's to deduce an error value.

User Benefit Characteristics of Universal Design Guidelines for Homes in Ireland (아일랜드 '주택을 위한 유니버설디자인 가이드라인'의 사용자 혜택 특성 연구)

  • Lee, Yeunsook;Ahn, Somi;Hyun, Jiwon;Park, Jaehyun
    • Korean Institute of Interior Design Journal
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    • v.26 no.2
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    • pp.72-82
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    • 2017
  • Current world population is rapidly ageing and the disabled population is expected to age seriously as well. The concern about the elderly and the disabled is increased largely not just the field of social welfare and service but the housing planning where the physical environment of everyday life is. Recently in Ireland, 'Universal Design Guideline for Homes' is established and proposed in public. It is considered as initial and special national policy for the socially venerable. The purpose of this research is to analyze the User Benefit Characteristics(UBC) of 'Universal Design Guideline for Homes in Ireland' and clearly organize the characteristics for comprehensive communication. The research subjects are 444 guidelines of 'Universal Design Guideline for Homes in Ireland.' The research is conducted by contents analysis technique, and each guideline is analyzed by the 4 main concepts of UBC- 'Behavioral Facilitation(BF)', 'Physiological Maintenance(PhM)', 'Perceptual Maintenance(PM)', 'Social Facilitation(SF).' As results, the User Benefit Characteristic of 'Universal Design Guideline for Homes in Ireland' is ordered by PhM>PM>BF>SF. The design guidelines are supposed to support ageing in place and sustainable living in the existing houses even though people are ageing or being disabled. 'Universal Design Guideline for Homes in Ireland' supports safe behavior and comfort cognition especially in indoor and surrounding outdoor environment. This research is significant for sharing the knowledge and comprehension of decreasing environmental stress of the elderly in specific, and could be utilized for developing new elderly housing in future.

Effectiveness of comprehensive traditional Korean Medicine treatment on quality of life, anorexia and cachexia of cancer patients : Retrospective chart review (암 환자의 삶의 질, 식욕 부진과 악액질에 대한 복합 한의 치료 프로그램의 효과: 후향적 차트 리뷰)

  • Han, Wonju;Lee, Eunji;Han, Gajin;Yoon, Sang-hoon;Han, Gajin;Leem, Jungtae
    • The Journal of Korean Medicine
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    • v.40 no.2
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    • pp.119-132
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    • 2019
  • Purpose: This study was conducted to collect and analyze real world data to evaluate the effectiveness and safety of comprehensive traditional Korean Medicine treatment on quality of life, anorexia and cachexia of cancer patients. Methods: We analyzed medical records of 62 cancer patients admitted to O-I Dang Korean Medicine Hospital from February 2018 to February 2019. The primary outcome was a change score in the Anorexia/Cachexia Subscale of Functional Assessment of Anorexia/Cachexia Therapy (FAACT). The secondary outcomes were Functional Assessment of Cancer Therapy-General (FACT-G), Trial Outcome Index(TOI) of FAACT, 11 point Pain Intensity Numeric Rating Score (11 PI-NRS) and Patient Global Impression of Change (PGIC) and adverse event. Results: Cachexia and quality of life in cancer patients assessed by FAACT, increased by $5.59{\pm}14.83$ (p=0.004) after treatment. PI-NRS was reduced by $2.10{\pm}1.81$ (p<0.001) and TOI and FACT-G total scores were increased by $5.17{\pm}11.70$ (p=0.001) and $3.59{\pm}10.94$ (p=0.012), respectively. These results were also clinically meaningful assessed via minimal clinically important difference (MCID). There was no severe adverse event. Conclusion: These findings suggest that comprehensive traditional Korean Medicine treatment might be effective and safe strategy for improving quality of life, anorexia, cachexia and pain of cancer patients. Further advanced studies with controlled group and more participants with rigorous design are needed to ensure these findings.

The Development of the Home Control System with the OSGi

  • Kim, Hee-Sun;;Lee, Chang-Goo
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.912-916
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    • 2004
  • The home network is the technique to guarantee a safe, economical, socially integrated, and healthy life to the family and it provides domestic safety, instrument control, controllable energy and health monitoring by the connection of the home appliances using wired and wireless networks. A home control system has been developed for managing and controlling home appliances. This paper designs the broadband PLC home controller using broadband PLC technology which can save much cost at a network infrastructure using the existing power line at a home and design the USB home controller using USB technology which is low cost and has many goods with it. And the embedded home server manages those. The CDMA module provides mobile functions to the home control system in this paper. And we choose the OSGi specification which is compatible with other home middleware and can accept various communication techniques of home network

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Investigation on the Strength and Vibration Safety of the Oxidizer Turbopump (산화제 터보펌프의 구조 강도 및 진동 안전성에 관한 연구)

  • Jeon, Seong-Min;Kim, Jin-han;Yang, Soo-Seok;Lee, Dae-Sung
    • The KSFM Journal of Fluid Machinery
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    • v.5 no.3 s.16
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    • pp.25-32
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    • 2002
  • Structural and dynamic analyses of inducer and impeller for an oxidizer turbopump are peformed to investigate the safety level of strength and vibration at a design point. Due to high rotational speed of turbopump, effects of centrifugal forces are carefully considered in the structural analysis. Hydrodynamic pressure is also considered as an external force applied to inducer and impeller blades. A three-dimensional Finite Element Method (FEM) is used for linear and nonlinear structural analyses with modified Newton-Raphson iteration method. After the nonlinear trim solution is obtained from the structural analysis, dynamic characteristics are obtained as a function of rotational speed from the linearized eigenvalue analysis at an equilibrium position. According to the results of numerical analysis, the safety margins of strength and vibration resonances are sufficient enough for safe operation within the requited life cycle.