• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.12-13
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• 2014

Domestic CM market has continued to grow, and the CM services in the international market is evaluated as a high value-added area. However, CM services are currently being challenged to perform its genuine CM roles because of the limitations by government's CM policies, market size, business functions, and technology capabilities. In order to identify the issues for revitalization of CM, this study analyzed the history of CM studies through a thorough review of the previous literatures that have been published since the enactment of CM policies in 1996. Based on this literature review, it is expected to suggest strategies that could improve current immature CM systems.

• Korean Journal of Construction Engineering and Management
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• v.7 no.1 s.29
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• pp.119-127
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• 2006

On December, 1996, the Ministry of Construction and Transportation published Construction Management Service in Construction Industry Basic Act. CM service has been adopted in Korean construction market for ten years by now, however there was no significant change in the construction industry from adoption of CM service. The CM service results aggregated by PCM, from 1997 to 2004, show that CM service adopted projects were 324 in total and the total contract amount was 260million US dollars. These results tell us that adoption of CM service in Korean construction industry is not successful. The research is to survey the factors and the limitations affecting on poor adoption of CM service and to propose the improving strategies on that matter. Therefore, this paper analyzes former papers, laws and regulations on CM and CM service results from PCM as well. From the analysis, we found conflicts in between the laws such as different rules on same matter or missing significant policies in their provisions. Also, problems of industrial organization was found such that the public sector seldom adopts CM service due to their embeded CM function.

• Korean Journal of Construction Engineering and Management
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• v.14 no.5
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• pp.113-121
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• 2013

An expansion into the global market increasingly becomes a buzz world among Construction Management(CM) firms in Korea. The objective of this study is to identify potential obstacles and investigate their nature and implications to CM firms in Korea. The study identified 25 obstacles under 5 categories. Base on a questionnaire survey and interviews with CM experts who have global CM projects experience, the study discusses that while there exist various types of obstacles, a more attention needs to be paid for a small number of major obstacles to minimine risks in overseas CM projects. It also suggests that improving pre-construction management competency through securing CM experts should be listed as a top agenda for Korean CM firms.

• Korean Journal of Exercise Nutrition
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• v.25 no.4
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• pp.10-16
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• 2021

[Purpose] The purpose of this study was to (i) assess hydration levels in elite male football players during a national team training camp before and during qualifying matches, (ii) evaluate the effect of coaching strategies for hydration based on feedback from hydration monitoring, and (iii) assess possible relationships between hydration status and training load or wellness markers. [Methods] Thirty-one male players (age 27±4 yrs; height 185±6 cm; weight 82.9±6.7 kg; body fat 10.4±2.3%) representing a national team from the Union of European Football Associations (UEFA) participated. The players were studied during three different national team training camps related to the UEFA Nations League tournament. Urine specific gravity (U_SG) was measured to assess hydration status. During all camps, the players were actively coached on improving strategies for hydration and given individual feedback on their test results. The training load was measured using GPS technology, and wellness questionnaires were completed. [Results] U_SG decreased progressively and significantly (p<0.005) during camp 1 and hydration status improved over the three camps, with fewer dehydrated and more well-hydrated players identified during the last part of camp 3. Significantly (p<0.05) higher U_SG values were observed 2 days prior to a match (MD-2) than on match day (MD); consequently, 52% of the players were dehydrated on MD-2 and only 6% on MD. No correlations were observed between hydration status and training load or wellness markers. [Conclusion] Dehydration is a challenge in elite male football, but continuous monitoring of hydration status and coaching on hydration strategies can lead to major improvements and reduce the degree of dehydration.

• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.97-107
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• 2016

CM services have been focused on the advancement of the CM industry and expansion to overseas market based on CM capabilities. However, there has been lack of quantitative and comprehensive research to investigate current CM trends and prospects for improving competitiveness. In this sense, the purpose of this study is to statistically analyze total of 3,453 CM service contracts over the past 18 years (between 1997 and 2014) in term of market type, contract size, owner's type, commodity type. Finding of this research reveal that 1) compared to 2005, CM market size in 2015 increased as much as 2.5 times, and that 2) domestic CM projects count for 87.5%, architectural project 88.4%, less than 1 billion won small contracts 75%, respectively. Also, recently as CM company are developing capability and competitiveness, 1) overseas CM market share has grown up to 20% among total CM contract amount, and 2) CM contracts by private owners has increased 3 times demanding the total management services based on high technical capability. Additionally, the result of this paper supports the growth path model proposed by Jung et al. (2014), where a path from Domestic Public (DP3) and Domestic Private (DC2) CM projects towards the expansion to International Private (IC5) contracts was quantitatively analyzed. Implications for other practical issues are also briefly discussed.

• Journal of Ecology and Environment
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• v.42 no.3
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• pp.128-138
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• 2018

Background: This study investigated the variation of soil organic carbon in four land cover types: natural and mixed forest, cultivated land, Eucalyptus plantation and open bush land. The study was conducted in the Birr watershed of the upper Blue Nile ('Abbay') river basin. Methods: The data was subjected to a two-way of ANOVA analysis using the general linear model (GLM) procedures of SAS. Pairwise comparison method was also used to assess the mean difference of the land uses and depth levels depending on soil properties. Total of 148 soil samples were collected from two depth layers: 0-10 and 10-20 cm. Results: The results showed that overall mean soil organic carbon stock was higher under natural and mixed forest land use compared with other land use types and at all depths ($29.62{\pm}1.95Mg\;C\;ha^{-1}$), which was 36.14, 28.36, and 27.63% more than in cultivated land, open bush land, and Eucalyptus plantation, respectively. This could be due to greater inputs of vegetation and reduced decomposition of organic matter. On the other hand, the lowest soil organic carbon stock under cultivated land could be due to reduced inputs of organic matter and frequent tillage which encouraged oxidation of organic matter. Conclusions: Hence, carbon concentrations and stocks under natural and mixed forest and Eucalyptus plantation were higher than other land use types suggesting that two management strategies for improving soil conditions in the watershed: to maintain and preserve the forest in order to maintain carbon storage in the future and to recover abandoned crop land and degraded lands by establishing tree plantations to avoid overharvesting in natural forests.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.335-342
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• 2003

This study was conducted to predict the carcass yield traits using ultrasound before slaughter and to enhance the prediction accuracy of carcass yield grade by applying various strategies. For this experiment, five hundred seventy three Hanwoo steers of 24 months of age were used. Difference between ultrasound result and carcass measure of BFT and LMA was 0.6$\pm$1.65mm and 0.7$\pm$5.56cm2, respectively. Correlation coefficient between ultrasound result and carcass measure of BFT and LMA was 0.86 and 0.82, respectively (p<0.001). Results for improving predictions of yield grade by four methods-the Korean yield grade index equation, fat depth alone, regression and decision tree methods were 80.3%, 81.3%, 80.1% and 81.8%, respectively. We conclude that the decision tree method can easily predict yield grade and is also useful for increasing prediction accuracy rate.

• Korean Journal of Materials Research
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• v.32 no.11
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• pp.481-488
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• 2022

The Cu₂ZnSn(S_xSe_1-x)₄ (CZTSSe) absorbers are promising thin film solar cells (TFSCs) materials, to replace existing Cu(In,Ga)Se₂ (CIGS) and CdTe photovoltaic technology. However, the best reported efficiency for a CZTSSe device, of 13.6 %, is still too low for commercial use. Recently, partially replacing the Zn²⁺ element with a Cd²⁺element has attracting attention as one of the promising strategies for improving the photovoltaic characteristics of the CZTSSe TFSCs. Cd²⁺ elements are known to improve the grain size of the CZTSSe absorber thin films and improve optoelectronic properties by suppressing potential defects, causing short-circuit current (J_sc) loss. In this study, the structural, compositional, and morphological characteristics of CZTSSe and CZCTSSe thin films were investigated using X-ray diffraction (XRD), X-ray fluorescence spectrometer (XRF), and Field-emission scanning electron microscopy (FE-SEM), respectively. The FE-SEM images revealed that the grain size improved with increasing Cd²⁺ alloying in the CZTSSe thin films. Moreover, there was a slight decrease in small grain distribution as well as voids near the CZTSSe/Mo interface after Cd²⁺ alloying. The solar cells prepared using the most promising CZTSSe absorber thin films with Cd²⁺ alloying (8 min. 30 sec.) exhibited a power conversion efficiency (PCE) of 9.33 %, J_sc of 34.0 mA/cm², and fill factor (FF) of 62.7 %, respectively.