• 제목/요약/키워드: Safe life design

검색결과 203건 처리시간 0.026초

노면 표면거칠기 특성의 대표값 정량화와 타이어 접촉력 해석 기법에 대한 고찰 (Representative Evaluation of Topographical Characteristics of Road Surface for Tire Contact Force Analysis)

  • 서범교;성인하
    • Tribology and Lubricants
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    • 제33권6호
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    • pp.303-308
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    • 2017
  • Most automobile tire companies have not yet considered the geometric information of a road at the design stage of a tire because the topographical characterization of a road surface is very difficult owing to its vastness and randomness. A road surface shows variable surface roughness values according to magnification, and thus, the contact force between the road and tire significantly fluctuates with respect to the scale. In this study, we make an attempt to define a representative value for surface topographical information at multi-scale levels. To represent surface topography, we use a statistical method called power spectral density (PSD). We use the fast Fourier transform (FFT) and PSD to analyze the height profiles of a random surface. The FFT and PSD of a surface help in obtaining a fractal dimension, which is a representative value of surface topography at all length scales. We develop three surfaces with different fractal dimensions. We use finite element analysis (FEA) to observe the contact forces between a tire and the road surfaces with three different fractal dimensions. The results from FEA reveal that an increase in the fractal dimension decreases the contact length between the tire and road surfaces. On the contrary, the average contact force increases. This result indicates that designing and manufacturing a tire considering the fractal dimension of a road makes safe driving possible, owing to the improvement in service life and braking performance of the tire.

클러치의 구조 안전 해석 (Structural Safety Analysis of Clutch System)

  • 조재웅;한문식
    • 한국자동차공학회논문집
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    • 제19권5호
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    • pp.148-155
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    • 2011
  • This study analyzes stress, fatigue and vibration at clutch on the rotation of wheel. Eigenfrequencies from 1'st to 6'th order about clutch assembly are shown with the vibration at more than 800Hz. Maximum equivalent stress is shown with the frequency of 800Hz in case of the harmonic vibration applied with force. Among the cases of nonuniform fatigue loads, 'SAE bracket history' with the severest change of load becomes most unstable but 'Sample history' becomes most stable. In case of 'Sample History' with the average stress of 0MPa to $-10^5$ MPa and the amplitude stress of 0MPa to $10^5$ MPa, the possibility of maximum damage becomes 3.23%. This stress state can be shown with 6 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The structural result of this study can be effectively utilized with the safe design of clutch.

부식을 고려한 해저 파이프라인의 확률론적 중량물 낙하 충돌 위험도 해석 (Probabilistic Risk Analysis of Dropped Objects for Corroded Subsea Pipelines)

  • 안쿠시 쿠마;서정관
    • 대한조선학회논문집
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    • 제55권2호
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    • pp.93-102
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    • 2018
  • Quantitative Risk Assessment (QRA) has been used in shipping and offshore industries for many years, supporting the decision-making process to guarantee safe running at different stages of design, fabrication and throughout service life. The assessments of a risk perspective are informed by the frequency of events (probability) and the associated consequences. As the number of offshore platforms increases, so does the length of subsea pipelines, thus there is a need to extend this approach and enable the subsea industry to place more emphasis on uncertainties. On-board operations can lead to objects being dropped on subsea pipelines, which can cause leaks and other pipeline damage. This study explains how to conduct hit frequency analyses of subsea pipelines, using historical data, and how to obtain a finite number of scenarios for the consequences analysis. An example study using probabilistic methods is used.

스마트폰 기반의 OTP 도어락 시스템 (Smartphone-based OTP Door Lock System)

  • 김진배;오창석;정시영;정상헌;김태용;장원태
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2015년도 추계학술대회
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    • pp.560-563
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    • 2015
  • 기존에 사용되어지는 도어락 시스템은 키 또는 카드, 패드를 이용하는 방식으로 복제, 분실, 훼손 등의 위험과, 타인에게 노출되는 문제점을 가지고 있다. 본 논문에서는 기존의 도어락 시스템 문제점을 보완하고자 스마트폰에 내장된 Bluetooth통신과 OTP(One-Time-Password), Hide-Key 인증방식 및 Arduino를 활용한 스마트폰 기반의 무선 OTP 도어락 시스템 설계 및 구현함으로써 사용자들은 보안 및 노출의 위험성에서 벗어나 보다 편리하고 안전한 생활을 가능하게 한다.

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제조물 책임법 시행에 따른 품질경영 정책 및 ISO 9000 시리즈의 수행 (Implementation of Quality Manageemtn Policy and ISO 9000 Series under Product Liability Law)

  • 변승남;이동훈
    • 품질경영학회지
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    • 제26권1호
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    • pp.27-47
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    • 1998
  • The primary objective of this research is to provide the basis of total quality management policies by reviewing previous studies which investigated effective ways to reduce product liability exposure. Specifically, the present study intends (1) to examine recent patterns and trends of product liability law in OECD countries, (2) to propose quality management policies for preventing product liability litigations, and (3) to guide the proper implementation process of ISO 9000 certification programs. The survey results show that the shift from a negligence law theory to strict liability is evident in most countries. The trend has led to make it easier for consumers to bring product liability lawsuits. Furthermore, the damage awards won by consumers have been drastically increasing. To minimize product liability exposure, manufactures should reflect comprehensive product safety concepts in establishing total quality management policies. Cooperative activities are also required between departments in companies to reach safe and satisfactory quality level. These quality management activities should be performed consistently during the total product life cycle. Failure to comply with the ISO 9000 certifications might be used as an evidence of negligence or as evidence of a design defect in court. Previous lawsuit cases, however, reveal that ISO 9001-9003 registration process alone is not sufficient in terms of product liability pervention perspectives. Therefore, manufactures should take into account ISO 9004 before implementing any other section of ISO 9000 standards.

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Lesson for New Urbanism from the Traditional Space in East Asia

  • Lee, Jawon
    • International Journal of Advanced Culture Technology
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    • 제6권4호
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    • pp.143-151
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    • 2018
  • Industrialization has accelerated the expansion of mobility to the urban areas, land use for function of residence and consumption. With the urbanization, the management and distribution of the physical space of the city and rational design have also become major issues. Rapid and widespread urbanization has consistently accumulated problems of natural, physical, environmental, and psychological circumstances, and most of urban areas have begun to focus on restoring an efficient, safe and healthy urban environment to improve of the quality of life since the latter half of the 20th century, New-Urbanism is a new urban development paradigm that resembles the practical implications of a shared economy for social, economic and environmental cost reduction.. The geographical significance of the sharing city's concept of the alleys is to revitalize sustainable cities while restoring the attractive elements of the city. This study examines the lessons of New-Urbanism in those traditional urban space comparing with each East Asia's cities such as golmok (alley or backlane) in Seoul, Huton in Beijing, Lilong in Shanghai, and Roji in Japan. This study diagnoses whether main principals of New-Urbanism such as development of good community and walkable pedestrian route, restoration of regional identity and sense of the place, and mitigation of climate change strategy can be practiced in the community of alley as well.

Design for Automation System for Pharmaceutical Prescription Using Arduino and Optical Character Recognition

  • Lim, Myung-Jae;Jung, Dong-Kun;Kim, Kyu-Dong;Kwon, Young-Man
    • International journal of advanced smart convergence
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    • 제10권3호
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    • pp.66-71
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    • 2021
  • Recent healthcare environments have characteristics of expanding the scope of healthcare-impacting healthcare, complexity resulting from diversification of components, and accelerating the pace of change. Drugs are used for the prevention, mitigation, and treatment of diseases, so they can inevitably cause harm, while they have efficacy and effectiveness, which are key elements of health recovery. Therefore, many countries regulate permits for safe and effective medicines, and also designate essential drugs directly related to life as pay targets and guarantee health insurance. Especially Pharmacist relying on manpower for composition medicine is liable for mal-manufacture due to combination of toxic medical substances or other chemical usage. In this paper, we focus on using Kiosk and Optical Character Recognition (OCR) for automated pharmacy to level up medical service and create labor friendly environment for pharmacist themselves through maintenance of prescription data and automated manufacturing solution. Presentation of drug substances and precautions will lead to efficient drug prescription and prevent misuse of information while auto manufacturing system efficiently maintain labor force and raise patient satisfaction level by reduction of waiting time.

Sequential treatment with transurethral resection and hormonal therapy for bladder endometriosis of vesicoureteric junction

  • Abdulelah AlAdimi;Nabil AlOdaini;Atef M. M. Darwish
    • Journal of Medicine and Life Science
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    • 제19권3호
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    • pp.116-120
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    • 2022
  • Objective: To estimate the efficacy of sequential treatment of bladder endometriosis (BE) of the vesicoureteric junction using transurethral resection (TUR) and hormonal therapy. Design: Case report. Setting: Private multispecialty hospital. Patient: A multiparous woman presented with perimenstrual lower urinary tract symptoms, cyclic chronic pelvic pain, and left loin pain. Intervention[s]: Ultrasonography revealed marked left renal dilatation. Computed tomography confirmed the presence of a bladder mass. A diagnostic cystoscopy revealed compression of the left vesicoureteral junction. Complete TUR BE with release of chocolate material during resection, followed by ureteric double J stent insertion for 3 months, was performed. Histopathology confirmed the diagnosis of BE, followed by adjuvant hormonal therapy (dienogest) for 3 months. Follow-up for about 2 years revealed complete relief of the symptoms without any recurrence. Main Outcome Measure[s]. Success and recurrence rates of sequential TUR and hormonal therapy of BE of the vesicoureteric junction. Result[s]. TUR BE followed by adjuvant hormonal therapy was very effective in eradicating BE of the vesicoureteric junction in a safe manner without recurrence on follow-up for 2 years. Conclusion[s]. BE of the vesicoureteric junction can be properly treated by sequential TUR and hormonal therapy without recurrence over a 2-year follow-up.

구조 해석을 통한 크루저 보드의 형상에 따른 융합 기술연구 (Study on Convergence Technique due to the Shape of Cruiser Board through Structural Analysis)

  • 이정호;조재웅
    • 한국융합학회논문지
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    • 제6권4호
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    • pp.99-105
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    • 2015
  • 오늘날 환경오염을 방지하기 위하여 화석연료를 사용하지 않는 크루저 보드의 1인승 이동수단이 주목을 받고 있다. 본 연구에서는 안전한 크루저 보드의 설계를 위하여 구조 해석을 수행함으로서 형상에 따른 크루저 보드의 특성들을 분석하고자 한다. 기존의 크루저 보드 모델과 새로운 형상의 크루저 보드 모델 총 두 가지 형상의 모델들을 설계하고, 유한요소해석 프로그램을 이용하여 구조 해석을 수행하여 변형량, 응력 및 피로 수명에 의한 내구성을 연구하였다. 연구 결과, 새로운 형상의 크루저 보드 모델이 최대 변형량은 0.000971mm, 최대 응력은 0.936MPa, 피로 수명은 $1827.7Cycle{\sim}1.887{\times}105Cycle$로서 새로운 모델에서의 모든 연구 결과 값들이 기존의 모델보다 더 양호하게 되어 새로운 모델이 기존의 모델보다 사용하기에 더 적합한 것으로 나타났다. 본 연구 결과는 더 안전하고 내구성이 있는 크루저 보드의 설계에 기여할 수 있으며, 디자인 면에서 융합 기술로의 접목도 가능하여 미적인 감각을 나타낼 수 있다.

임대주택단지의 생활안전 위해요인 해소방안 (Resolution Method of Hazard Factor for Life Safety in Rental Housing Complex)

  • 손정락;조건희;김진원;송상훈
    • 토지주택연구
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    • 제8권1호
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    • pp.1-11
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    • 2017
  • The government has been constructing and supplying public rental housing to ordinary people in order to stabilize housing since 1989. However, the public rental houses initially supplied to ordinary people are at high risk for safety accidents due to the deterioration of the facilities. Therefore, this study is aimed to propose a solution to solve the life safety hazards of the old rental housing complex as a follow-up study of Analysis of Accident Patterns and Hazard Factor for Life Safety in Rental Housing Complex. Types of life safety accidents that occur in public rental housing complexes are sliding, falling, crash, falling objects, breakage, fire accidents, traffic accidents and criminal accidents. The types of safety accidents that occur in rental housing complexes analyzed in this study are sliding, crashes, falling objects, and fire accidents. Although the incidence of safety accidents such as falling, breakage, traffic accidents and crime accidents in public rental housing complexes is low, these types are likely to cause safety accidents. The method of this study utilized interviews and seminar results, and it suggested ways to solve the life safety hazards in rental housing complexes. Interviews were conducted with residents and managers of rental housing complexes. Seminars were conducted twice with experts in construction, maintenance, asset management, housing welfare and safety. Through interviews and seminars, this study categorizes the life safety hazards that occur in rental housing complexes by types of accidents and suggests ways to resolve them as follows. (1) sliding ; use of flooring materials with high friction coefficient, installation of safety devices such as safety handles, implementation of maintenance, safety inspections and safety education, etc. (2) falling ; supplementation of safety facilities, Improvement of the design method of the falling parts, Safety education, etc. (3) crash ; increase the effective width of the elevator door, increase the effective width of the lamp, improve the lamp type (U type ${\rightarrow}$ I type), etc. (4) falling objects and breakage ; design of furniture considering the usability of residents, replacement of old facilities, enhancement of safety consciousness of residents, safety education, etc. (5) fire accidents ; installation of fire safety equipment, improvement by emergency evacuation, safety inspection and safety education, etc. (6) traffic accidents ; securing parking spaces, installing safety facilities, conducting safety education, etc. (7) criminal accidents; improvement of CCTV pixels, installation of street lights, removal of blind spots in the complex, securing of security, etc. The roles of suppliers, administrators and users of public rental housing proposed in this study are summarized as follows. Suppliers of rental housing should take into consideration the risk factors that may arise not only in the design and construction but also in the maintenance phase and should consider the possibility of easily repairing old facilities considering the life cycle of rental housing. Next, Administrators of rental housing should consider the safety of the users of the rental housing, conduct safety checks from time to time, and immediately remove any hazardous elements within the apartment complex. Finally, the users of the rental housing needs to form a sense of ownership of all the facilities in the rental housing complex, and efforts should be made not to cause safety accidents caused by the user's carelessness. The results of this study can provide the necessary information to enable residents of rental housing complexes to live a safe and comfortable residential life. It is also expected that this information will be used to reduce the incidence of safety accidents in rental housing complexes.