• Title/Summary/Keyword: Work loss

Search Result 1,368, Processing Time 0.027 seconds

Assessment of design methods for punching through numerical experiments

  • Kotsovou, Gregoria M.;Kotsovos, Gerasimos M.;Vougioukas, Emmanuel
    • Computers and Concrete
    • /
    • v.17 no.3
    • /
    • pp.305-322
    • /
    • 2016
  • The work is intended to demonstrate that the loss of bond between concrete and flexural steel which led in recent years a number of flat-slab structures to punching collapse under service loading conditions is also relevant to ultimate limit-state design. It is based on a comparative study of the results obtained from numerical experiments on flat slab-column sub-assemblages. The slabs were designed for punching either in compliance with the EC2 code requirements, which do not allow for such loss of bond, or in accordance with the compressive force-path method which considers the loss of bond between concrete and the flexural reinforcement in tension as the primary cause of punching. The numerical experiments are carried out through the use of a nonlinear finite element analysis package for which, although ample published evidence of its validity exists, additional proof of its suitability for the purposes of the present work is presented.

Exergy Analysis of Nitrogen Distillation Column in the Cryogenic Air Separation Process (심랭식공기분리공정에서 질소증류탑의 엑서지 해석)

  • 용평순;이성철
    • Progress in Superconductivity and Cryogenics
    • /
    • v.4 no.1
    • /
    • pp.145-150
    • /
    • 2002
  • The distillation column is one of large energy consumable units in the cryogenic air separation process and the accurate energy analysis of this unit is necessary for choice of energy saving process. In this work, the energy method was adopted for energy analysis of a cryogenic nitrogen distillation column. In order to designing the energy saving distillation column, the exergy distribution of feed air, exergy efficiency and exergy loss for process condition was investigated and the optimal process condition to minimize the exergy loss was found. The result from this work can be used as a guideline for the choice of the process design conditions and efficiency improvement of cryogenic distillation column.

Characteristics of Replacement of Labor following Accidents in Agriculture (농작업 재해 발생에 따른 대체인력 고용 특성)

  • Lee, Yun Keun;Park, Hee Sok;Kim, Hyo Cher;Kim, Gyung Ran;Lee, Kyung Suk
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.28 no.4
    • /
    • pp.346-351
    • /
    • 2018
  • Objective: This study aims to provide information needed to determine the wages paid for replacement labor for work lost following accidents in agricultural operations. Methods: Visits and interviews were conducted with 171 farmers who experienced a loss of at least one day of work due to an agricultural workplace accident. Results: It was found that only 35.1% of the study participants hired replacement labor, and more replacement labor was hired in greenhouse and fruit workplaces than in open field work. The mean number of days of hiring replacement labor was 14.6 days, and no significant differences were found between the national average wage and the surveyed value, while female workers were paid less than their male counterparts. Conclusions: The results from this study would be of help in determining a reasonable level of compensation for lost work.

Conservation in Contemporary Art (현대미술 개념의 보존)

  • Kim Ken
    • 한국문화재보존과학회:학술대회논문집
    • /
    • 2005.11a
    • /
    • pp.154-159
    • /
    • 2005
  • The most common conception of a work of art is as a unique object. In conservation the prevalent notion of authenticity is based on physical integrity, this guides judgements about loss. For the majority of traditional art objects, minimising change to the physical work means minimising loss, where loss is understood as compromising the (physical) integrity of a unique object, and this forms the focus of conservation. Fundamental to conservators' approach to the conservation of contemporary art is the notion that the artist's intent should guide conservators' practice. Since most of the artists creating installation art are living, it is possible to interview them about the details of the installation, attitudes to changing technology, parameters of acceptable change and their views about what aspects of the installation are essential to preserve. Conservation is no longer focused on intervening to repair the art object but has become concerned with documentation and determining what change is acceptable and managing those changes. In order to accurately install works in the future it is necessary to broaden our focus to include elements of an installation that affect the viewer's experience. This might mean documenting the space, the acoustics, the balance of the different channels of sound, the light levels and the way one enters and leaves the installation. These are as important as the more tangible or material elements in the conservation of the work. It is also necessary to work with industry and specialists outside the field of conservation to develop new skills to preserve and manage new types of objects in our care. We can also document the less tangible details of an installation such as the light levels, the character of the sound etc. This is a new area of conservation and as a profession our understanding and knowledge will deepen with time. All of these strategies work together to help to limit the risk of not being able to accurately install these works in the future. Deciding what can be changed and how to best care for any element of an installation will depend on its meaning and role. For both contemporary and traditional objects such decisions are documented by conservators and although the focus of the conservator may have moved away from the material object, the approach is still rooted in traditional notions of collection care.

  • PDF

The Risk Rating System for Noise-induced Hearing Loss in Korean Manufacturing Sites Based on the 2009 Survey on Work Environments

  • Kim, Young-Sun;Cho, Youn-Ho;Kwon, Oh-Jun;Choi, Seong-Weon;Rhee, Kyung-Yong
    • Safety and Health at Work
    • /
    • v.2 no.4
    • /
    • pp.336-347
    • /
    • 2011
  • Objectives: In Korea, an average of 258 workers claim compensation for their noise-induced hearing loss (NIHL) on an annual basis. Indeed, hearing disorder ranks first in the number of diagnoses made by occupational medical check-ups. Against this backdrop, this study analyzed the impact of 19 types of noise-generating machines and equipment on the sound pressure levels in workplaces and NIHL occurrence based on a 2009 national survey on work environments. Methods: Through this analysis, a series of statistical models were built to determine posterior probabilities for each worksite with an aim to present risk ratings for noise levels at work. Results: It was found that air compressors and grinding machines came in first and second, respectively in the number of installed noise-generating machines and equipment. However, there was no direct relationship between workplace noise and NIHL among workers since noise-control equipment and protective gear had been in place. By building a logistic regression model and neural network, statistical models were set to identify the influence of the noise-generating machines and equipment on workplace noise levels and NIHL occurrence. Conclusion: This study offered NIHL prevention measures which are fit for the worksites in each risk grade.

Influence of Current Distributions on AC Loss Characteristics in a 3-conductor (전류분포가 3본-도체의 교류손실 특성에 미치는 영향)

  • 정재훈;류경우
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2003.02a
    • /
    • pp.206-209
    • /
    • 2003
  • AC loss is an important issue in the design of high-T$_{c}$ superconducting power cables which consist of a number of Bi-2223 tapes wound on a former. In the cables, the tapes have different critical currents intrinsically. And they are electrically connected to each other and current leads. These make loss measurements considerably complex, especially for short samples of laboratory size. So special cautions are required in the positioning of voltage leads for measuring the true loss voltage. In this work we have prepared a conductor composed of three Bi-2223 tapes with different critical currents. The ac loss characteristics in the conductor have experimentally investigated. The loss tests indicate that the ac loss is dependent on arrangements of voltage leads but not on their contact positions. The measured losses in the conductor also agree well with the sum of the transport losses measured in each Bi-2223 tape.e.

  • PDF

Influence of Current Distributions on AC Loss Characteristics in a 3-conductor (전류분포가 3본-도체의 교류손실 특성에 미치는 영향)

  • 정재훈;류경우
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2003.02a
    • /
    • pp.7-10
    • /
    • 2003
  • AC loss is an important issue in the design of high-T$_{c}$ superconducting power cables which consist of a number of Bi-2223 tapes wound on a former. In the cables, the tapes have different critical currents intrinsically. And they are electrically connected to each other and current leads. These make loss measurements considerably complex, especially for short samples of laboratory size. So special cautions are required in the positioning of voltage leads for measuring the true loss voltage. In this work we have prepared a conductor composed of three Bi-2223 tapes with different critical currents. The ac loss characteristics in the conductor have experimentally investigated. The loss tests indicate that the ac loss is dependent on arrangements of voltage leads but not on their contact positions. The measured losses in the conductor also agree well with the sum of the transport losses measured in each Bi-2223 tape.e.

  • PDF

Aerosol Wall Loss in Teflon Film Chambers Filled with Ambient Air

  • Lee Seung-Bok;Bae Gwi-Nam;Moon Kil-Choo
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.20 no.E1
    • /
    • pp.35-41
    • /
    • 2004
  • Aerosol wall loss is an important factor affecting smog chamber experiments, especially with chambers made of Teflon film. In this work, the aerosol wall loss was investigated in 2.5 and $5.8-m^3$ cubic-shaped Teflon film chambers filled with ambient air. The natural change in the particle size distribution was measured using a scanning mobility particle sizer in a dark environment. The rate of aerosol wall loss was obtained from the deposition theory suggested by Crump and Seinfeld (1981). The measured rates of aero-sol wall loss were In a good agreement with the theoretical and experimental values given by McMurry and Rader (1985), implying that the electrostatic effect enhances particle deposition on the chamber wall. The significance of aerosol wall loss correction was demonstrated with the photochemical reaction experiments using the ambient air.

A Study on Efficiency Improvement of the Safety Management Personnel System in Construction Site (건설공사 현장 안전관리 인적 체계 효율성 개선에 관한 연구)

  • You, Hee-Jae
    • Journal of the Korea Safety Management & Science
    • /
    • v.20 no.1
    • /
    • pp.11-21
    • /
    • 2018
  • Safety accidents, which are called industrial accidents in construction work, are often caused by unstable physical and personal conditions combined during preparation and execution of work. It is difficult to manage all the construction works, but especially in the field of apartment construction work, complex and many kinds of works are being carried out at the same time. In the current construction, safety regulations such as safety management guidelines are generally well maintained, but the execution of manpower resources that can fulfill them is limited, and it is difficult to reduce the accident rate and loss cost. Therefore, in this study, it is a reality that most of the types of construction work are under contruction by subcontracting contract, so they are limit by methods of manual maintenance and safety education. Currently, the subcontractor is also allowed to perform safety management through the composition of the safety management review body, but it is operated formally. So alternatives to this were studied. As a result, safety accidents occur in the subcontractor's worker due to vertical integration, which is characteristic of the construction industry, together to the contractor, the safety management system is based on a safety construction system in which a worker who has a certain qualification condition such as career experience of the work type, work understanding of the work type, and management experience of the work type among the subcontractor, when we manage based on mutual personality which is the personality of interpersonal relationship that can communicate with each other by work type, process and grouping, it is concluded that effective and practical safety management can be achieved to reduce the accident rate and loss cost.

Facilitators and Barriers in the Use of a Checklist by Insurance Physicians during Work Ability Assessments in Depressive Disorder

  • Blok, Sebastiaan;Gouttebarge, Vincent;Slebus, Frans G.;Sluiter, Judith K.;Frings-Dresen, Monique H.W.
    • Safety and Health at Work
    • /
    • v.2 no.4
    • /
    • pp.328-335
    • /
    • 2011
  • Objectives: Depressive disorder (DD) is a complex disease, and the assessment of work ability in patients with DD is also complicated. The checklist depression (CDp) has recently been developed to support such work ability assessments and has been recommended for implementation in insurance medicine, starting with an analysis of the organisational and social contexts. The aim of this study was to identify the potential facilitators and barriers in the use of the CDp by insurance physicians (IPs) during work ability assessments of employees on sick leave due to DD. Methods: A qualitative research was conducted based on semi-structured interviews. The participants were IPs with at least one year of work experience in performing work ability assessments. The interviews were audiotaped, transcribed and analysed qualitatively. Results: Ten IPs (7 males, 3 females; mean 53 years) were interviewed. Important facilitators, which emerged for use of the CDp, were an oral introduction for colleagues and staff, support from management, valuing the increased transparency in work ability assessments with using the CDp, having adequate time for assessments as well as modification of the appearance (colour, plasticised form) and content (clarifying aspects of the examples) of the assessment tool. The fear of the loss of autonomy, lack of added value of the CDp, high workload, inadequate instructions and lack of time were mentioned as barriers. Conclusion: Adequate introduction to the use of CDp and the fear of the loss of autonomy of IPs need special attention in planning its implementation.