• Title/Summary/Keyword: high-performance

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Work Productivity Analysis of High-performance PC Slab Installation

  • Shin, Young-su;Cho, Kyuman;Cho, Chang-geun
    • International conference on construction engineering and project management
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    • 2015.10a
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    • pp.616-617
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    • 2015
  • Demand is increasing for large, high-rise, and complex buildings, which is leading to advances in the development of high-performance structural systems. In this context, precast concrete (PC) technology has received a large amount of attention owing to its benefits in terms of schedule reduction, high quality, and easy installation. In addition, advanced methodologies that improve the PC performance by the addition of various materials have recently been reported. Research on analyzing the effects of such high-performance PC on the construction process and productivity is very limited. This makes it difficult for decision-makers to apply PC to particular projects. Thus, the aim of this research was to analyze the work productivity of the high-performance PC slab installation process by using a construction simulation tool to resolve critical issues. In this study, a real construction project that adopted PC slab installation work was analyzed, and a sensitivity analysis was performed to confirm the reliability of the analysis results.

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Analysis of Seismic Performance of Slim Flat Plate System in High-rise Hybrid Structural System (슬림형 바닥시스템을 이용한 고층 복합구조의 내진성능에 관한 해석적 연구)

  • Ha Gee Joo;Park Hyo Sun;Park Joung Hyen;Choi Kyung Ryeol;Kim Dae Joung;Jung Jea Kwang
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.11a
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    • pp.77-80
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    • 2005
  • Recently the construction of high-rise hybrid type building is progressively increased as the social demands. It is significantly important factors such as economy, the safety of structure, and the flexibility of internal space. Therefore new hybrid structural system, using slim flat plate system, is also required to be attained the reduction of story height, the flexibility and efficient use of space. The most suitable structural system is ,with the economy and flexibility, flat plate system in high-rise hybrid type building. But it was focused in the seismic performance for high performance flat plate system in high-rise hybrid type building. Therefore, in the study, to develop the new flat-plate system with high ductile, durable, good performance for the applications. It was evaluated the seismic performance in the critical region of slab-column connection. And then high performance flat plate system, designed by the economy and safety, was developed as a new technique in the application of high-rise hybrid type building.

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Comparison of Heart Rate Variability according to Performance in Elite Female Judo Athletes

  • Bae, Moon-jung;Kim, Hyun-Chul;Park, Ki-Jun
    • Journal of the Korean Society of Physical Medicine
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    • v.15 no.1
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    • pp.11-18
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    • 2020
  • PURPOSE: This study was to investigate examined the differences in the autonomic nervous functions of elite female judo athletes according to their performance by measuring the heart rate variability (HRV). METHODS: Sixteen elite female judo players participated in this study. The participants were divided into a high performance and low performance group according to the results of their competitions. The HRV (mean heart rate, SDNN, RMSSD, TP, LF, HF, LF/HF ratio) was measured in the resting status. A t-test was used to compare the two groups, and bivariate logistic regression analysis was performed to determine the HRV elements that affect performance. The data were analyzed using IBM SPSS Statistics ver. 24.0 (IBM Co., Armonk, NY, USA). RESULTS: The mean heart rate was higher in the high performance group (72.88) than in the low performance group (64.75) (p=.049). The LF/HF ratio was higher in the high performance group (3.43) than in the low performance group (0.83), and the results were significant (p=.038). No HRV elements having a significant effect on the performance were observed. CONCLUSION: This study showed that the activity of the sympathetic nervous system was dominant in the high performance group in the resting status than in the low performance. The high performance group is believed to be in the overtraining status who experience more stress.

Comparison of Knee Extensor and Hip Extensor Strength According to Wall Squat Performance

  • Jung, Sung-hoon;Kim, Moon-hwan;Hwang, Ui-jae;Kim, Jun-hee;Kwon, Oh-yun
    • Physical Therapy Korea
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    • v.24 no.1
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    • pp.79-85
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    • 2017
  • Background: The wall squat is considered an effective exercise because it can reduce the knee load and prevent excessive lumbar movement. However, the relationship between wall squat performance and strength of knee extensors and hip extensors remained unclear. Objects: The purpose of this study was to compare the strengths of the knee extensors and hip extensors between groups with low and high wall squat performance. Method: Nineteen males (low performance group: 9 subjects, high performance group: 10 subjects) participated in this study and performed wall squats. The subjects who were performing less than 30% of the average wall squat count were classified into the low wall squat performance group (less than or equal to 4 times) and the subjects who performed more than 30% of the average wall squat count were classified into the high wall squat performance group (greater than or equal to 8 times). Knee extensor and hip extensor strength were measured with a strength measurement system. An independent t-test was used to compare the strengths of the knee extensors and hip extensors between the groups with low and high wall squat performance. Results: The ratios of knee extensor and hip extensor strength to bodyweight were greater in the high wall squat performance group than in the low wall squat performance group (knee extensors: p<.001; hip extensors: p=.03). In the high- and low-performance groups, the ratios of knee extensor strength to bodyweight were $42.74{\pm}5.72$ and $30.76{\pm}8.54$, respectively, and the ratios of hip extensor strength to bodyweight were $31.95{\pm}10.61$ and $20.66{\pm}11.25$, respectively. Conclusion: Our findings suggest that knee extensor and hip extensor strength are needed for high wall squat performance. Thus, exercise to increase the knee and hip extensors strength can be recommended to improve squat performance.

Enhancing the Performance of High-Strength Concrete Members Using Hybrid Reinforcing Technique (하이브리드 보강기법을 활용한 고강도 콘크리트 구조 부재의 성능 향상)

  • Yang, Jun-Mo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2010.05a
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    • pp.479-480
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    • 2010
  • The efforts to achieve high-performance, durable reinforced concrete structures have increased the demands for improving the performance of both the concrete and the reinforcing materials. Researches for the hybrid reinforcing technique, which is maximizing the performance of high-strength concrete structures by applying the combination of high performance reinforcing materials, were performed in this study.

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High performance silicone for quality assurance of inter-layer joint in apartment house (공동주택 층간조인트 품질확보를 위한 고성능 실리콘 개발)

  • Seo, Tae-Seok
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.11a
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    • pp.201-202
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    • 2022
  • In this study, the high performance silicone was developed to assure the inter-layer joint in apartment house. The tensile strength, the elongation, the bond strength and the fatigue tests were conducted. As a result, it was confirmed that the performance of high -performance silicone was superior to the existing elastic paint. Therefore, it is expected that it will help to secure the quality of inter-layer joints in apartment houses.

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A Study on the Validity and Reliability of Performance Assessment in Home Economics (가정과 수행평가의 타당성과 신뢰성 연구 - 경남 농촌지역의 소인수 학급을 대상으로 -)

  • 윤성희;유태명
    • Journal of the Korean Home Economics Association
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    • v.39 no.10
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    • pp.169-186
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    • 2001
  • The purpose of the study was to verify validity and reliability of performance assessment in home economics by applying performance assessment tools developed by Korean Curriculum Assessment Institute and by the researcher to a class of 17 high school female students in a rural area. For the purpose of this study, the research question was formulated and addressed:“How are the validity and reliability of performance assessment in home economics\ulcorner” The results of the study were as follows. 1. The results of testing validity a. Thirteen high school home economics teachers, whose average teaching years is ten years verified high validity in the contents of performance assessment. b. In the validity of the items that is verified being based on the scores of high school entrance examination of 2000 school year, the essay type showed its characteristics as performance assessment. c. The generalizability among assessment methods was not high. 2. The results of testing reliability Both Cronbach's $\alpha$, inter-item reliability of the assessment tools used in the research, and reliability among the raters were high. But reliability among the tasks was relatively low. This study proposed that the diverse performance methods, the increasing number of assessment, the explicit assessment criterion, and scoring criterion are needed to satisfying validity and reliability of performance assessment.

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The Study on the Relationships between IT Investments and Firm's Performance: The Differences According to the Levels of IS Strategic Applications and PEU (제조기업의 정보기술 투자와 기업 성과 간의 관계 연구: 전략적 활용 수준과 환경 불확실성에 따른 차이)

  • Choe, Jong-min
    • The Journal of Information Systems
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    • v.29 no.2
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    • pp.1-26
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    • 2020
  • Purpose This study empirically investigates the impact of information technology(IT) investments on the financial and non-financial performance of a manufacturing firm. We examined the interaction effects of IT investments and strategic applications levels of information systems(IS). This study also demonstrated the three-way interaction effects of IT investments, levels of IS strategic applications, and perceived environmental uncertainty(PEU). Design/methodology/approach For this study, empirical data were collected from 98 manufacturing firms with the structured questionnaires. The data were analyzed with multiple regression models, and partial derivatives were utilized to identify the directions of the impact. Findings From the empirical results, it was found that when both the levels of IS strategic applications and the degrees of IT investments are high, the ratios of the costs of goods sold to total sales(RCGS) and the labor costs to total sales(RLCS) are decreased, as it were, the performance of a firm is improved. However, it was observed that when the levels of strategic IS are low, the high degrees of IT investments do not contribute to the improvement of a performance. The results showed that when the levels of strategic IS are high, the high degrees of IT investments incur the high RSAE not low RSAE. When PEU is considered, the empirical results showed that under the low degrees of PEU, the IT investments under high levels of strategic IS applications (strategic IT investments) improve the performance, as it were, low RCGS, and high degrees of perceived financial and non-financial performance. However, under high PEU, it was observed that high degrees of strategic IT investments do not increase the performance. When PEU is high, the strategic IT investments reduce RSAE, and under low PEU, RSAE is increased.

A comparative study on performance goal priority of workforce training project of Small and Medium Business(SMB) Specialized Vocational High Schools by existence of teaching staff's assignment (교원의 보직 유무에 따른 중소기업특성화고 인력양성사업 성과 목표 우선순위 비교 연구)

  • Lee, Byung Wook;Lee, Sang hyun
    • 대한공업교육학회지
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    • v.43 no.2
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    • pp.61-78
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    • 2018
  • The purposes of this study are to importance and performance of performance goal of workforce training project of SMB Specialized Vocational High Schools by existence of teaching staff's assignment and compare difference of the priority for performance goal of two groups by IPA. Research problems for them are as follows. First, how about differences of the importance for performance goal of workforce training project of SMB Specialized Vocational High Schools by existence of teaching staff's assignment? Second, how about differences of the performance for performance goal of workforce training project of SMB Specialized Vocational High Schools by existence of teaching staff's assignment? Third, how about differences of the priority for performance goal of workforce training project of SMB Specialized Vocational High Schools by existence of teaching staff's assignment? Results obtained by this study are as follows. First, performance goal of workforce training project of SMB Specialized Vocational High Schools that teaching staffs recognize the most importantly regardless of the existence of assignment was 'improvement of students' adaptation to the filed' in area of 'employment competency strengthening'. Second, performance goal of workforce training project of SMB Specialized Vocational High Schools that teaching staffs recognize the degree of high performance regardless of the existence of assignment was 'expansion of SMB employment opportunity' in area of 'employment connection'. Third, regardless of the existence of teaching staff's assignment, areas of high priority in performance goal of workforce training project of SMB Specialized Vocational High Schools were 'improvement of teaching staff's understanding for SMB' and 'improvement of SMB understanding for Specialized Vocational High School' in area of 'improvement of SMB mind for Specialized Vocational high School'.

Silencer structure for exhaust noise attenuation performance in the high frequency range (500 Hz 이상 고주파수 영역에서 배기소음 저감을 위한 소음기 구조)

  • KIM, Sang-Am
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.54 no.3
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    • pp.255-261
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    • 2018
  • High power trends in the diesel engines due to engine downsizing do not provide noise attenuation that can be satisfied with the performance of the existing silencer on account of high frequency increases in the exhaust noise. This study improves the attenuation performance of the exhaust silencer of the diesel engine and suggests silencer structure that performs best attenuation performance, especially at the high frequency range in the exhaust noise. It proposes dual silencer structure with an average attenuation performance of 6.4 dB and a maximum of 10.7 dB in the high frequency range (over 500 Hz), and analyzes its characteristics compared with the existing silencer. The performance analysis is performed according to 'Measurements on silencers in situation-ISO 11820:1996 Acoustics' and describes the results of comparative analysis with the existing silencer.