• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.222-226
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• 2008

The construction industry has remained stagnant for a long time. So many researchers have wanted to solve this problem not only focusing on enhancement of construction process, but also introducing the culture of cooperation. The Last Planner System(LPS), one of the elementary techniques of Lean Construction, aims for improving the work reliability and reducing variability by measuring and managing the daily or weekly performance for overcoming the weakness of recent complex schedule management tools such as Critical Path Method. This research propose a framework for implementation of LPS conducted by owner focused on construction stage and introduce optimal owner participation model in plant construction, based on needs analysis for construction participants. Furthermore, this research introduce a modified needs analysis, so called IPBA(Importance-Performance-Betterment Analysis), and an advanced LPS procedure which add the needs analysis during pre-LPS and(or) main LPS stages.

• Tunnel and Underground Space
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• v.18 no.4
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• pp.289-299
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• 2008

Based on the case study on the causes for the failure of cutting slope composed of weathered rock and soil, the factors influencing the design of a cutting slope have been examined, This type of rock and soil is widely distributed on the region whose parent rock is granite. To analyze the stability of the cutting slope, the following series of progress has been conducted: (1) ground characterization by geological survey and ground investigation, (2) the safety factor examination by limit equilibrium analysis and numerical analysis and (3) the comparison and analysis of rainfall and failure history. As a result, the main factors to cause the failure is determined to be the decrease of shear strength in the upper parts whose ground condition is weakened during localized heavy rain. Moreover, the analysis indicates the failure is also closely related to the groundwater inflow path. On the base of this investigation, a reinforcement method is proposed to ensure the stability of the cutting slope.

• Journal of the Korean Society of Propulsion Engineers
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• v.27 no.1
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• pp.37-48
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• 2023

In this study, performance analysis modeling of two spool mixed flow type turbofan engine according to steady-state and transient is performed. The target engine is selected as F100-PW-229 from Pratt & Whitney, and main engine components including fan, high pressure compressors, combustion, high pressure turbines, low pressure turbines, mixer, convergent-divergent nozzle are modeled. The cooling effect of turbine through secondary flow path are considered in engine simulation model. We develop in-house Matlab/Simulink-based engine performance analysis program capable of analyzing internal engine state and compare it with GASTURB which is generally used as a commercial engine analysis program.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.4
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• pp.50-65
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• 2021

In this study, the water flow system by measuring the flow-way type and distance of flow path that composes the Gugok through literature survey, field survey, and map work on Gugok gardens in Korea whose existence has been confirmed, while investigating and analyzing watersheds, river orders, and river grades. It was intended to reveal the watershed distribution and stream morphological characteristics of the Gugok gardens and to use them as basic data for future enjoyment and conservation of the Gugok gardens. The conclusion of the study is as follows. First, Of the 93 Gugok gardens that have been confirmed to exist, it was found that 11 places(11.8%) were found to have a descending(top-down) type of Gugok that develops while descending along a stream. Second, As a result of analysis of the length of the flow path for each valley, Okryudonggugok(玉流洞九曲, Namsan-gugok) in Gimcheon, Gyeongsangbuk-do was found to have the shortest length of 0.44km among the surveyed valleys, while the flow distance of Muheulgugok(武屹九曲) located in Seongju-gun and Gimcheon-si, Gyeongsangbuk-do was 31.1km, showing the longest flowing distance. The average flow path length of the Gugok Garden in Korea was 6.24km, and the standard deviation was 4.63km, indicating that the deviation between the 'curved type'e and the 'valley type' was severe. In addition, 14(15.1%) Gugok gardens were found to be partially submerged due to dam construction. Third, As a result of analyzing the waters area where Gugok garden is located, the number of Nakdong river basins was much higher at 52 sites(55.9%), followed by the Hangang river basin at 27 sites(28.7%), the Geum river basin at 9 sites(9.7%), and the Yeongsan river and Seomjin river basins at 5(5.4%). Fourth, All Gugok gardens located in the Han river region were classified as the Han river system, and the Gugok garden located on the Nakdong river was classified as the main Nakdong river system, except for 7 places including 5 places in the Nakdong Gangnam Sea water system and 2 places in the Nakdong Gangdong sea water system. As a result of synthesizing the river order of the flow path where Gugok garden is located, Gugok, which uses the main stream as the base of Gugok, is 3 places in the Hangang water system, 5 places in the Nakdong river system, 2 places in the Geumgang water system, and 1 place in the Yeongsangam/Seomjin river system. A total of 11 locations(11.5%) were found, including 36 locations(38.2%) in the first branch, 29 locations(31.2%) in the second branch, and 16 locations(17.0%) in the third branch. And Gugok garden, located on the 4th tributary, was found to be Taehwa Five-gok(太華五曲) set in Yonghwacheon Stream in Cheorwon in the Han river system, and Hoenggyegok(橫溪九曲) in Yeongcheon Hoenggye Stream in the Nakdong river system. Fifth, As a result of the river grade analysis of the rivers located in the Gugok garden Forest, the grades of the rivers located in the Gugok garden were 13 national rivers(14.0%), 7 local first-class rivers(7.5%), and 74 local second-class rivers(78.5%) was shown.

• Fire Science and Engineering
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• v.33 no.2
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• pp.30-38
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• 2019

Tracking, which is one of the main causes of electrical fires, is perceived as a physical phenomenon of electrical discharge. Hence tracking should be explained based on electric field analysis, conduction path by electron generation, and gas discharge physics. However, few papers have considered these details. This paper proposes a tracking mechanism including their effects on tracking progress. In order to prove this mechanism, a tracking experiment, an electric field analysis for the carbonization evolution model, and an explanation of the tracking process by gas discharge physics were conducted. From the tracking experiment, the current waveforms were measured at each stage of the tracking progress from corona discharge to tracking breakdown. The electric field analysis was carried out in order to determine the electric field on the surface of a dry-band and the high electric field region for electron generation during the generation and progress of carbonization. In this paper, the proposed tracking mechanism consisted of six stages including electron avalanche by corona discharge, accumulation of positive ions, expansion of electron avalanche, secondary electron emission avalanche, streamer, and tracking by conductive path. The pulse current waveforms measured in the tracking experiment can be explained by the proposed tracking mechanism. The results of this study will be used as the technical data to detect tracking phenomenon, which is the cause of electric fire, and to improve the proof tracking index.

• Health Policy and Management
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• v.18 no.3
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• pp.1-17
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• 2008

The measurement and management of patient satisfaction has become one of the key issues in the last two decades. Hospitals must thoroughly understand the needs of their customers and design products and health services that meet and exceed their expectations. The importance-performance analysis(IPA) is a widely used analytical technique that yields strategies for managing customer satisfaction in a variety of applications. IP A is a two-dimensional grid based on customer-perceived importance of quality attributes and attribute performance. Depending on the interplay of these two dimensions, four strategies can be derived. The aim of this study is to develop the management strategies for improving patient satisfaction in university hospitals using the I-P analysis. The attributes on inpatient service quality in 4 university hospitals was investigated using the Martilla and James(l977)' s a mean adjusted I-P grid where the axes of the grid cross at the average rating point of all items. The patient satisfaction questionnaires were completed by 600 hospital inpatients. The main statistical methods are path analysis and IPA with SPSS 12.0 and AMOS 4.0 statistical softwares. The two attributes, physician and medical service, administrative staff kindness attributes position in first quadrant(Keep Up the Good domain). The nurse and nursing service attributes position in second quadrant(Possible Overkill domain). The two attributes, convenience of check-in service, facilities and physical environment position in third quadrant(Low Priority domain). Finally the quality of inpatient service(food etc.) attributes position in fourth quadrant(Concentrate Here domain). These findings show various implications on the development of strategies in university hospitals in the future. It was determined that quality of inpatient service(food etc.) need to concentrate more on investments. These investments include a taste, price, proper provision of food service and quick response of pain management. A low priority was given to investment in streamlining the check-in process of inpatient and hospital facilities and physical environment in the long run.

• The Korean Journal of Health Service Management
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• v.8 no.2
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• pp.49-59
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• 2014

This study attempted to provide some implications for human resource management of health services organizations by investigating the influence of job rotation on motivation and organizational commitment. For empirical analysis, a study model based on literature review of previous researches was developed, and a survey was conducted for the employees of 8 hospitals located in Busan area. In processing the data, frequency analysis, correlation analysis and path analysis were performed using SPSS 18.0 and AMOS 18.0. Main results of empirical analysis can be summarized as follows: First, procedure of job rotation, did not significantly affect tissue immersion and stimulation, but effect of job rotation, has been found to provide a significant effect. Second, motivation was shown to have a significant influence on emotional and normative commitments, sub-factors of organizational commitment variable. In conclusion, suggest that intentions and opinions of the organizational members need to be actively reflected in job rotations of which the effect can be maximized when they are regularly and reasonably implemented.

• Geotechnical Engineering
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• v.5 no.3
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• pp.19-28
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• 1989

This study has been carried out as a fundamental course for the analysis of the constitutive- equation for the materials like sands being hardened during Ehear. For this aim, experimentall tests with variable stress paths for the concrete material are performed using the cubical multi- axial test in which the three principle stresses are arbitrarily controlled. Stress-strain behaviors. and strength characteristics are suggested in octahedral planes. Various tests such as HC, CTC, . TC, 55 are performed. The main results summarized are as follows; 1. The order of strength from the largest to the smallest is CTC, TC, SS, and TE test. 2. The octahedral Ehear strength of concrete specimens is dependent upon the stress path(8) 3. There is a direct relation between strength and confining pressure. 4. The ultimate envelopes in the octahedral planes are non-circular-cone shaped. 5. Any ultimate criteria used to predict the strength behavior of concrete must include thin effect of the tensile stresses.

• Spatial Information Research
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• v.4 no.1
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• pp.43-54
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• 1996

The purpose of this study is to provide GIS application to the emergency medical service management system in the Seoul area. Two wards, Kangnam-Gu and Songpa-Gu, were selected for a pilot study subject. The main focus of the study was to develope the network system using GIS which could select the most available hospital from the site being emergency case and advise the minimum path to the hospital. ARC/INFO pc version was need to implemeni an indexing system for automated mapping and data storage. The developed system, "Emergency Medical System based on GIS ${\ulcorner}$EMS/GIS${\lrcorner}m$", consists of the cartographic database and vehicle transportation system. The results suggest that EMS/GIS network are needed to connect the local transportation network between major emergency care hospitals and central conirol tower in the near future. If the EMS/GIS system could be more developed based in further analysis, it would be the most useful economical and efficient for emergency medical service with mutual aid system.al aid system.

• Journal of Power Electronics
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• v.15 no.5
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• pp.1217-1226
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• 2015

In a grid-connected photovoltaic (PV) system, the traditional Z-source inverter uses a low frequency transformer to ensure galvanic isolation between the grid and the PV system. In order to combine the advantages of both Z-source inverters and transformerless PV inverters, this paper presents a modified single-phase transformerless Z-source PV grid-connected inverter and a corresponding PWM strategy to eliminate the ground leakage current. By utilizing two reversed-biased diodes, the path for the leakage current is blocked during the shoot-through state. Meanwhile, by turning off an additional switch, the PV array is decoupled from the grid during the freewheeling state. In this paper, the operation principle, PWM strategy and common-mode (CM) characteristic of the modified transformerless Z-source inverter are illustrated. Furthermore, the influence of the junction capacitances of the power switches is analyzed in detail. The total losses of the main electrical components are evaluated and compared. Finally, a theoretical analysis is presented and corroborated by experimental results from a 1-kW laboratory prototype.