• Title/Summary/Keyword: Work duration

Search Result 794, Processing Time 0.022 seconds

A Study of the Sustainable Management Method for Construction phase (건설 공종별 친환경 시공 관리 방안)

  • Park, Ji-Ho;Kim, Tae-Kyoung;Kim, Kyung-Rai
    • Proceedings of the Korean Institute Of Construction Engineering and Management
    • /
    • 2007.11a
    • /
    • pp.961-966
    • /
    • 2007
  • Recently the regulation related the environment is getting more and more strengthened. Needs for sustainable building is growing more and more interested in construction industry. However, most of the research has been conducted is focused on material production or maintaining phases. There are not enough research especially in construction phase. And it still exists a lot of environmental barrier factor which could not be easily quantified in construction fields. It makes problems that contractors make an effort only an adequate regulation and they does not take an interest in reducing efforts of environmental pollution. This research defines factor categories which have to be mainly managed and provides the integrated construction management method for sustainable building to reduce environmental pollution through analysis of environmental barrier factor in each work package and effective adjustment of construction plan.

  • PDF

Predictive model of fatigue crack detection in thick bridge steel structures with piezoelectric wafer active sensors

  • Gresil, M.;Yu, L.;Shen, Y.;Giurgiutiu, V.
    • Smart Structures and Systems
    • /
    • v.12 no.2
    • /
    • pp.97-119
    • /
    • 2013
  • This paper presents numerical and experimental results on the use of guided waves for structural health monitoring (SHM) of crack growth during a fatigue test in a thick steel plate used for civil engineering application. Numerical simulation, analytical modeling, and experimental tests are used to prove that piezoelectric wafer active sensor (PWAS) can perform active SHM using guided wave pitch-catch method and passive SHM using acoustic emission (AE). AE simulation was performed with the multi-physic FEM (MP-FEM) approach. The MP-FEM approach permits that the output variables to be expressed directly in electric terms while the two-ways electromechanical conversion is done internally in the MP-FEM formulation. The AE event was simulated as a pulse of defined duration and amplitude. The electrical signal measured at a PWAS receiver was simulated. Experimental tests were performed with PWAS transducers acting as passive receivers of AE signals. An AE source was simulated using 0.5-mm pencil lead breaks. The PWAS transducers were able to pick up AE signal with good strength. Subsequently, PWAS transducers and traditional AE transducer were applied to a 12.7-mm CT specimen subjected to accelerated fatigue testing. Active sensing in pitch catch mode on the CT specimen was applied between the PWAS transducers pairs. Damage indexes were calculated and correlated with actual crack growth. The paper finishes with conclusions and suggestions for further work.

Variation of EEG Band Powers Related with Human Errors in Knowledge-based Responses (지식기반 반응 시 인간과오 관련 뇌파 밴드파워의 변화)

  • Lim, Hyeon-Kyo;Kim, Hong-Young
    • Journal of the Korean Society of Safety
    • /
    • v.28 no.3
    • /
    • pp.107-113
    • /
    • 2013
  • Problem solving and/or decision making process usually encountered in human living consists of a sequence of human behaviors based upon his/her knowledge. Thus, Rasmussen introduced Skill-Rule-Knowledge paradigm to countermeasure human errors that can occur in Nuclear Power Plants. Unfortunately however, it was not so easy as expected since objective evidence have not been obtainable with conventional research techniques. With the help of EEG band pawer ratio techniques, this study tried to get psycho-physiological symptoms of human errors, if any, while human beings perform knowledge-based behaviors such as simple arithmetic computations with different difficulty level. A set of simulated works was carried out with a computer station. Four kinds of arithmetic computation tasks were given to 10 health male under-graduate students on different day individually, and during the experiment, EEG and ECG was measured continuously for objective psycho-physiological analysis. According to the results, ${\alpha}$/(${\alpha}+{\beta}$) as well as ${\alpha}/{\beta}$ band power ratio were sensitive to task difficulty level which consistently decreased both. However, any one of them failed to reveal the influence of tasks with different difficulty level in the aspect of task duration time. On the contrary, Heart Rate Variability was more suggestive than expected. To make a conclusion, it can be said that band power of EEG waves will be helpful in not only assessment of work difficulty level but also assessment of workers' skill development if supported by cardiac function such as HRV.

Evaluation of Potential Amount of Groundwater Development in Chungju Basin by Using Watershed Hydrologic Model and Frequency Analysis (유역수문모형과 빈도해석을 이용한 충주댐 상류유역 지하수 개발가능량의 평가)

  • Lee, Jeong-Eun;Kim, Nam-Won;Chung, Il-Moon;Lee, Jeong-Woo
    • Economic and Environmental Geology
    • /
    • v.41 no.4
    • /
    • pp.443-451
    • /
    • 2008
  • Memon(1995) pointed out that the groundwater recharge from the precipitation is affected by various factors such as the occurrence, intensity, duration, and seasonal distribution of rainfall; air temperature, humidity, and wind velocity; the character and thickness of the soil layer above the water table; vegetated cover, soil moisture content, depth to the water table, topography; and land use. To reflect above factors, groundwater recharge in Chungju basin is computed by using the SWAT-K which is a longterm continuous watershed hydrologic model. Frequency analysis is adopted to evaluate the existing values of potential amount of groundwater development which is made by the 10 year drought frequency rainfall multiplied by recharge coefficient. In this work, the recharge rates of 10 year drought frequency in subbains were computed and compared with the existing values of potential amount of groundwater development. This process could point out the problems of existing precesses used for computing potential amount of groundwater development.

Chemical Risk Assessment Screening Tool of a Global Chemical Company

  • Tjoe-Nij, Evelyn;Rochin, Christophe;Berne, Nathalie;Sassi, Alessandro;Leplay, Antoine
    • Safety and Health at Work
    • /
    • v.9 no.1
    • /
    • pp.84-94
    • /
    • 2018
  • Background: This paper describes a simple-to-use and reliable screening tool called Critical Task Exposure Screening (CTES), developed by a chemical company. The tool assesses if the exposure to a chemical for a task is likely to be within acceptable levels. Methods: CTES is a Microsoft Excel tool, where the inhalation risk score is calculated by relating the exposure estimate to the corresponding occupational exposure limit (OEL) or occupational exposure band (OEB). The inhalation exposure is estimated for tasks by preassigned ART1.5 activity classes and modifying factors. Results: CTES requires few inputs. The toxicological data, including OELs, OEBs, and vapor pressure are read from a database. Once the substance is selected, the user specifies its concentration and then chooses the task description and its duration. CTES has three outputs that may trigger follow-up: (1) inhalation risk score; (2) identification of the skin hazard with the skin warnings for local and systemic adverse effects; and (3) status for carcinogenic, mutagenic, or reprotoxic effects. Conclusion: The tool provides an effective way to rapidly screen low-concern tasks, and quickly identifies certain tasks involving substances that will need further review with, nevertheless, the appropriate conservatism. This tool shows that the higher-tier ART1.5 inhalation exposure assessment model can be included effectively in a screening tool. After 2 years of worldwide extensive use within the company, CTES is well perceived by the users, including the shop floor management, and it fulfills its target of screening tool.

The Influence of Organizational External Factors on Construction Risk Management among Nigerian Construction Companies

  • Adeleke, A.Q.;Bahaudin, A.Y.;Kamaruddeen, A.M.;Bamgbade, J.A.;Salimon, Maruf Gbadebo;Khan, Muhammad Waris Ali;Sorooshian, Shahryar
    • Safety and Health at Work
    • /
    • v.9 no.1
    • /
    • pp.115-124
    • /
    • 2018
  • Background: Substantial empirical research has shown conflicting results regarding the influence of organizational external factors on construction risk management, suggesting the necessity to introduce a moderator into the study. The present research confirmed whether rules and regulations matter on the relationships between organizational external factors and construction risk management. Methods: Based on discouragement and organizational control theory, this research examined the effects of organizational external factors and rules and regulations on construction risk management among 238 employees operating in construction companies in Abuja and Lagos, Nigeria. A personally administered questionnaire was used to acquire the data. The data were analyzed using partial least squares structural equation modeling. Results: A significant positive relationship between organizational external factors and construction risk management was asserted. This study also found a significant positive relationship between rules and regulations and construction risk management. As anticipated, rules and regulations were found to moderate the relationship between organizational external factors and construction risk management, with a significant positive result. Similarly, a significant interaction effect was also found between rules and regulations and organizational external factors. Implications of the research from a Nigerian point of view have also been discussed. Conclusion: Political, economy, and technology factors helped the construction companies to reduce the chance of risk occurrence during the construction activities. Rules and regulations also helped to lessen the rate of accidents involving construction workers as well as the duration of the projects. Similarly, the influence of the organizational external factors with rules and regulations on construction risk management has proven that most of the construction companies that implement the aforementioned factors have the chance to deliver their projects within the stipulated time, cost, and qualities, which can be used as a yardstick to measure a good project.

The Effect Common Health Disorders of Foreign Workers - Focused on Daegu and Kyungpook Region - (외국인 근로자들의 일상적인 건강장애에 미치는 영향 - 대구경북지역을 중심으로 -)

  • Kim, Seung-Dae
    • The Journal of the Korea Contents Association
    • /
    • v.9 no.9
    • /
    • pp.268-277
    • /
    • 2009
  • This study seeks to promote the mental and physical efficiencies of the foreign workers working in our country through the promotion of their health, and provide help in their effective use of medical treatments and granting appropriate medical benefits, and provide the basic information helpful in managing the health of the foreign workers who are playing a role in the advancement of the industry in Korea for the companies and employers that are employing them by researching the health condition and management status centering on the foreign workers from a part of Asia and South America who are working in our country. I made a regression analysis toward 231 foreign workers who have employed in industrial workplace from Mar. 1 to Jun. 30, 2008. The result said the factors that affect significant impact on common health disorder of foreign workers in their daily circumstances were staying period in Korea($\beta$=.270),difficulty to access hospital($\beta$=.268), inferior sanitation of work place($\beta$=.218), smoking or not($\beta$=.170), actual condition of health maintenance($\beta$=-.251).($R^2$=0.501)

Fibrin affects short-term in vitro human mesenchymal stromal cell responses to magneto-active fibre networks

  • Spear, Rose L.;Symeonidou, Antonia;Skepper, Jeremy N.;Brooks, Roger A.;Markaki, Athina E.
    • Biomaterials and Biomechanics in Bioengineering
    • /
    • v.2 no.3
    • /
    • pp.143-157
    • /
    • 2015
  • Successful integration of cementless femoral stems using porous surfaces relies on effective periimplant bone healing to secure the bone-implant interface. The initial stages of the healing process involve protein adsorption, fibrin clot formation and cell osteoconduction onto the implant surface. Modelling this process in vitro, the current work considered the effect of fibrin deposition on the responses of human mesenchymal stromal cells cultured on ferritic fibre networks intended for magneto-mechanical actuation of in-growing bone tissue. The underlying hypothesis for the study was that fibrin deposition would support early stromal cell attachment and physiological functions within the optimal regions for strain transmission to the cells in the fibre networks. Highly porous fibre networks composed of 444 ferritic stainless steel were selected due to their ability to support human osteoblasts and mesenchymal stromal cells without inducing untoward inflammatory responses in vitro. Cell attachment, proliferation, metabolic activity, differentiation and penetration into the ferritic fibre networks were examined for one week. For all fibrin-containing samples, cells were observed on and between the metal fibres, supported by the deposited fibrin, while cells on fibrin-free fibre networks (control surface) attached only onto fibre surfaces and junctions. Initial cell attachment, measured by analysis of deoxyribonucleic acid, increased significantly with increasing fibrinogen concentration within the physiological range. Despite higher cell numbers on fibrin-containing samples, similar metabolic activities to control surfaces were observed, which significantly increased for all samples over the duration of the study. It is concluded that fibrin deposition can support the early attachment of viable mesenchymal stromal cells within the inter-fibre spaces of fibre networks intended for magneto-mechanical strain transduction to in-growing cells.

Developing Method of Auxiliary Label by Korean Braillewritier Letter for Drug Consultation (한국인 시각 장애우 환자의 복약지도 증진을 위한 점자용 보조라벨 개발의 필요성과 개발방법 제시)

  • Lim, Sung-Cil;Lee, Myung-Koo;Lee, Chong-Kil;Lee, Bo-Reum
    • YAKHAK HOEJI
    • /
    • v.52 no.3
    • /
    • pp.201-211
    • /
    • 2008
  • All pharmacists must provide the drug consultation whenever dispense drugs to patients by the Korean Pharmacy Law. Drug consultation is very important procedure for increasing pharmacotherapy. Because it maximizes the therapeutic effects or/and minimizes adverse drug reaction during the drug therapy. However, it is not easy to do because of the dynamic and hectic pharmacy environment. Especially, if someone has a disabling body function, they required more time and efforts to perform consultation by pharmacist. Currently several auxiliary labels for helping drug consultation are using in pharmacy practice but not for disabling patients. Therefore we developed the total 53 auxiliary labels with size of 0.7 cm (width) and 1 cm (length) by Braillewriter letters for blind patients. This research has been performed for total 12 months (Mar. 15ts, 2007$\sim$Feb. 25th, 2008) and the developing methods are consisted of 4 steps: 1) selection of essential informations, 2) simplification of information, 3) changing for Braillewriter letters, 4) application and revising by blindness patients. Also the labels are consisted of 12 for adverse reactions and precautions, 8 for directions, 2 for storages, 9 for duration, 9 for dosage forms, and 12 for common names. After developed those labels, we revised those labels by discussion with 2 blind people. In conclusion, the new auxiliary labels for blind patients can increase therapeutic effects and decrease risks from pharmacotherapy besides decreasing of pharmacist's work load in the future.

A study on the practical use of smart meter end-user demand data (스마트미터 데이터 활용 방법에 대한 연구)

  • Park, Geunyeong;Jung, Donghwi;Jun, Sanghoon
    • Journal of Korea Water Resources Association
    • /
    • v.54 no.10
    • /
    • pp.759-768
    • /
    • 2021
  • This work introduces a new approach that classifies individual household water usage by examining the characteristics of smart meter end-user demand data. Here, one of the most well-known unsupervised machine learning, K-means algorithm, is applied to classify water consumptions by each household. The intensity and duration of end-user demands are used as main features to determine the households with similar water consumption pattern. The results showed that 21 households are classified into 13 clusters with each cluster having one, two, three, or five houses. The reasoning why multiple households are classified into the same cluster is described in this paper with respect to the collected data and end-user water consumption behavior.