• Journal of Construction Engineering and Project Management
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• 제1권1호
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• pp.37-43
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• 2011

Labor productivity is a significant factor associated with controlling time, cost, and quality. Many researchers have developed models to define methods of measuring the relationship between productivity and various parameters such as the size of working area, maximum working hours, and the crew composition. Most of the previous research has focused on estimating productivity; however, this research concentrates on estimating labor productivity and developing time and cost data for repetitive concrete pouring activity. In Korea, "Standard Estimating" only entails the average productivity data of the construction industry, and it is difficult to predict the time and cost spent on any particular project. As a result, errors occur in estimating duration and cost for individual activities or projects. To address these issues, this research sought to collect data, measure productivity, and develop time and cost data using labor productivity based on field conditions from the collected data. A probabilistic approach is also proposed to develop data. A case study is performed to validate this process using actual data collected from construction sites. It is possible that the result will be used as the EVMS baseline of cost management and schedule management.

• 천문학회보
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• 제36권1호
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• pp.29.2-29.2
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• 2011

Although stellar flares have a long history of observations, there are few concrete understanding about underlying physical processes and meaningful correlations with other stellar properties. Most of previous observations dealt with only a small number of sample stars, and therefore not sufficient to support generalized statistical studies. Based on one-month long MMT time-series observations of the open cluster M37, we monitored light variations of nearly 2,500 M-dwarf stars and successfully identified 606 flare events from 422 stars. This is a rare attempt to estimate true flare rates and properties among many stars of the same age and mass group. For each flare, we considered both observational and physical parameters including flare shape, duration before and after the peak, baseline magnitude before and after the peak, peak magnitudes, total energy and peak energy, etc. We find significant correlations between some of key parameters over a wide range of energy ($Er=10^{32}{\sim}10^{36}ergs$). For instance, regardless of stellar luminosities, the energy power spectrum of flares can be approximated by a power law (${\beta}=0.83-0.97$). This suggests that flares follow similar physical mechanisms for atmospheric heating and cooling among these low-mass stars. From this MMT data set, we derived an average flaring rate of $0.019 hr^{-1}$ among flare stars and $0.003 hr^{-1}$ for all M-dwarf candidates. We will report the details of our analysis and discuss physical implications.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.256-261
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• 2011

Labor productivity is a significant factor related to control time, cost, and quality. Many researchers have developed models to define method of measuring the relationship between productivity and various constraints such as the size of working area, maximum working hours, and the crew composition. Most of the previous research has focused on estimating productivity; however, this research concentrates on estimating labor productivity and developing time and cost data for repetitive concrete pouring activity. In Korea, "Standard Estimating" only contains the average productivity data of the construction industry, and it is difficult to predict the time and cost of any particular project; hence, there are some errors in estimating duration and cost for individual activity and project. To address these issues, this research collects data, measures productivity, and develops time and cost data using labor productivity based on field conditions from the collected data. A probabilistic approach is also proposed to develop data. A case study is performed to validate this process using actual data collected from construction sites and it is possible that the result will be used as the EVMS baseline of cost management and schedule management.

• 한국학교ㆍ지역보건교육학회지
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• 제18권1호
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• pp.57-68
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• 2017

Objectives: The purpose of the study was to evaluate the effect of community intervention on reducing salt intake among college students on their knowledge, attitude and practice of low-salt diet. Methods: A community intervention planned to increase college students' knowledge, attitude and practice of low-salt diet. The intervention comprised of 1 lecture on salt and health, 4 campaigns on low-salt diet, and 2 taste testing was carried out from March 24 to May 19, 2015. All the intervention was open to entire university while data was collected from a panel of convenient sample. We used the baseline data of 251 students, 226 students completed post-test. Post-test data on knowledge, attitude, and practice, blood pressure measurement, and urine salt test were collected on May 25 and 26 by trained nursing students and graduates. Baseline data were collected on March 17 and 18. Data were analyzed using IBM-SPSS 21.0 for t-test and ANCOVA. Results: Regarding a general characteristic and health behavior, there was statistically significant difference in living arrangement(p<0.001), amount of monthly allowance(p=0.005) and frequency of eating-out(p<0.001) between the two regions in this study. However, there was no statistically significant difference in gender, major, smoking, drinking and frequency of breakfast. Regarding a characteristic related to low-salt diet, there was statistically significant difference in diastolic blood pressure level(p=0.002), urine test(p=0.001). But there was no statistically significant difference in knowledge, attitude, practice of low-salt diet and systolic blood pressure. There was no statistically significant difference in their knowledge of low-salt diet(F=1.588, p=0.209), attitude(F=2.182, p=0.141), practice(F=3.507, p=0.062) and systolic blood pressure(F=1.723, p=0.191), diastolic blood pressure(F=1.552, p=0.214), urine test after a community intervention. Conclusions: Community intervention that does not have concrete target group doesn't seem to be effective on increasing knowledge, attitude and practice of the entire community, not even in university-a somewhat closed community. It is suggested to apply a target specific intervention in order to have efficient and effective outcome from a intervention.

• 한국지리정보학회지
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• 제11권4호
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• pp.41-50
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• 2008

육상자원에 대한 치열한 경쟁 속에 많은 나라들이 바다(해양자원)로 눈을 돌리고 있다. 따라서 세계 각국의 배타적경제수역(EEZ)과 대륙붕의 경계를 명확하게 하기위해 첨예하게 대립하고 있다. 1982년 해양법 협약(UNCLOS)이후, 한국과 일본, 한국과 중국의 인접수역이 400해리 미만으로 한국은 일본 중국과 해양경계획정 회담을 해오고 있다. 본 연구는 해양법과 기술지침서 IHO-51을 통해 해상경계의 획정을 위해 가장 중요한 법률과 기술을 검토하고 주변국과의 해양경계 협상에 효과적인 해양경계 GIS DB를 정의하였다. 영해기점과 영해기선의 정의는 해양의 경계를 획정하기위해 가장 중요한 개념으로 국가 간 협의과정과 협상에 임하기 위해서 정책결정자들은 해양법 협약을 바탕으로 자국에 이익을 최대화 할 수 있는 해상 경계를 획정할 준비가 되어 있어야 한다. 협상 전략과 원칙은 해양경계 결정과 관련된 요소들의 신뢰할 수 있는 데이터베이스를 통해 구체적으로 만들어 진다. 따라서 협상에 대한 효율적이고 신속정확한 의사결정은 해상경계 결정을 위한 GIS DB를 근거하여 만들어 질수 있다.

• 토지주택연구
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• 제3권4호
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• pp.415-421
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• 2012

최근 도시 미관이 중요시 되면서 동일 아파트 건설단지 내에서 저층과 고층 아파트가 혼합배치되는 경우가 많아지고 있다. A공사에서 발주한 아파트 사업지구 중 고층 동들과 저층 동들 간의 층수 차가 4층 이상인 지구가 약 33%인 것으로 조사되었다. 일반적으로 아파트 공사의 공기는 단지 내최고층 동을 기준으로 산정한다. 이로 인해 전체 사업지구의 공사기간이 길어지고, 길어진 공기는 해당사업의 사업성에 나쁜 영향을 미친다. 그러므로 동일 단지 내 저층 고층 아파트 동들이 혼합 배치된 사업지구(이하 "혼합사업지구"라 한다)의 사업성 제고를 위해 일부 고층동 아파트의 골조공기를 단축해야 할 것이다. 그러나 혼합사업지구의 다양한 유형으로 인해 어떤 경우에는 공기단축이 사업성을 더 나쁘게 만들 수 있다. 따라서 본 연구에서는 다양한 유형을 갖고 있는 혼합사업지구의 골조공기 단축 여부를 판단할 수 있는 자료제공을 위해 혼합사업지구의 일부 고층동에 대한 골조공기 단축이 건설사업비에 미치는 영향을 분석하여 그 결과를 제시하였다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.525-536
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• 2009

The current residential process adheres to a traditional method of construction involving wood framing on-site on poured concrete foundations which has been widely applied in North America. A conventional residential construction process can include seventeen distinct stages ranging from stake-out to pre-occupancy inspection. The current practice possesses short comings including high construction material wastes, long scheduling timelines, adverse weather conditions, poor quality, low efficiencies and negative environmental impacts from transportation and equipment use. Over CAN $5 billion dollars was spent in the construction sector during 2007 in Canada. Previous findings in CO₂ emissions during the construction process of a conventional dwelling emphasize more than 45 tonnes of CO₂ emissions. Hence, in Alberta alone during 2007, almost 50,000 residential units would release more than two million tonnes of CO₂. These numbers demonstrate the economical and environmental impact in building construction and its relationship with CO₂ emissions. The aim of this paper is to quantify the CO₂ emissions from the current residential construction process in order to establish the baseline for CO₂ emission reduction opportunities. The quantification collection methodology will be approached by identifying the seventeen various stages of construction and quantifying the contributions of CO₂ from specific activities and their impacts of work for each stage. The approach of separating these into separate stages for collection will allow for independent opportunities for analysis from various independent contractors from the entire scope of work. The use of BIM will be implemented to efficiently quantify CO₂ emissions. Based on the CO₂ quantification baseline, emission reduction opportunities such as an industrialized construction process will be introduced that allows homebuilders to reduce the environmental and economical impact of home construction while enabling them to produce higher quality, more energy efficient homes in a safer and shorter period of time.

• 한국치위생학회지
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• 제9권1호
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• pp.101-111
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• 2009

Objectives : The purpose of this study was to evaluate the use of oral hygiene products in Korean adult population. And it was conducted to make a baseline in planning the operation of the oral health for the Korean adult. Methods : The National Survey data of Oral Health was used. The use of each oral hygiene product was analysed according to socioeconomic status (Age, Occupation, Residential district), smoking status and concern about one's oral health. The subject of this study were 14,368 of 2000 year, 3,526 of 2003 year and 2,439 of 2006 year. They were organized from 20s to 60s. Data was analysed into Pearson chi-square test and Fisher's exact test using SAS 8.01 program. Results : 1. The rate of using oral hygiene product was increased, but the rate of non-using people remains 65.8% on the 2006 data. 2. The non-using group of the oral hygiene products was the age of sixty, farmer, rancher, fisherman, military, ruralist, smoker and the people do not concern about their oral health(p<0.05). Conclusion : To improve the rate of using oral hygiene products, effective motivation method would be necessary. In addition, It is required to educate the group more individually. This is for them to have a interesting about oral hygiene products and learn how to choice appropriate product. In the future, study about the reason of non-using oral hygiene products, and more concrete method for improving their behavior would be needed.

• Structural Engineering and Mechanics
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• 제40권4호
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• pp.471-488
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• 2011

The Ting Kau Bridge in Hong Kong is a cable-stayed bridge comprising two main spans and two side spans. The bridge deck is supported by three towers, an end pier and an abutment. Each of the three towers consists of a single reinforced concrete mast strengthened by transverse cables and struts. The bridge deck is supported by four inclined planes of cables emanating from anchorages at the tower tops. In view of the heavy traffic on the bridge, and threats from typhoons and earthquakes originated in areas nearby, the dynamic behaviour of long-span cable-supported bridges in the region is always an important consideration in their design. Baseline finite element models of various levels of sophistication have been built not only to match the bridge geometry and cable forces specified on the as-constructed drawings but also to be calibrated using the vibration measurement data captured by the Wind and Structural Health Monitoring System. This paper further describes the analysis of axle loading data, as well as the generation of random axle loads and simulation of vibrations of the bridge using the finite element models. Various factors affecting the vehicular loading on the bridge will also be examined.

• Nuclear Engineering and Technology
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• 제51권8호
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• pp.2018-2025
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• 2019

This study systematically compared two hybrid deterministic/Monte Carlo transport codes, ADVANTG/MCNP and MAVRIC, in solving a difficult shielding problem for a real-world spent fuel storage cask. Both hybrid codes were developed based on the consistent adjoint driven importance sampling (CADIS) methodology but with different implementations. The dose rate distributions on the cask surface were of primary interest and their predicted results were compared with each other and with a straightforward MCNP calculation as a baseline case. Forward-Weighted CADIS was applied for optimization toward uniform statistical uncertainties for all tallies on the cask surface. Both ADVANTG/MCNP and MAVRIC achieved substantial improvements in overall computational efficiencies, especially for gamma-ray transport. Compared with the continuous-energy ADVANTG/MCNP calculations, the coarse-group MAVRIC calculations underestimated the neutron dose rates on the cask's side surface by an approximate factor of two and slightly overestimated the dose rates on the cask's top and side surfaces for fuel gamma and hardware gamma sources because of the impact of multigroup approximation. The fine-group MAVRIC calculations improved to a certain extent and the addition of continuous-energy treatment to the Monte Carlo code in the latest MAVRIC sequence greatly reduced these discrepancies. For the two continuous-energy calculations of ADVANTG/MCNP and MAVRIC, a remaining difference of approximately 30% between the neutron dose rates on the cask's side surface resulted from inconsistent use of thermal scattering treatment of hydrogen in concrete.