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A Study on the Validation of Destructive Leadership Scale of Local Police Manager (지역경찰 현장관리자의 파괴적리더십 척도의 타당성 연구)

  • Park, Jin-Woo;Lee, Chang-Han;Shim, Myung-Sub
    • Korean Security Journal
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    • no.51
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    • pp.39-58
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    • 2017
  • The purpose of this study is to verify the validation of the Korean-type destructive leadership scale in order to activate the leadership research of local police manager in Korea. For the purpose of this study, the entire police officer(under the rank of sergeant) working at the Gyeongnam Provincial Police Agency in 2017 was set up as the population. A proportional allocation sampling was used for the sampling, and the allocation standard was set up in the workplace, department, rank, and sex. Data collection was conducted from April 1, 2017 to April 30, 2017, for a total of 500 respondents, and 433 were finally used for actual analysis. In the study, reliability and validity of destructive leadership scale were verified through reliability analysis, exploratory factor analysis, and confirmatory factor analysis. As a result, the destructive leadership scale of Korean local police manager showed a high cronbach' ${\alpha}$ coefficient of 0.948 for the questionnaire related load and 0.974 in the questionnaire related organization, but, the model fit of confirmatory factor analysis was low. Therefore, through additional exploratory factor analysis and confirmatory factor analysis, we reconstructed 6 questionnaires by deleting 4 questionnaires among the load-related items. On the other hand, the organization-related items were verified to be appropriate for all of the existing 10 items, and the destructive leadership scale of Korean local police manager was finally reconstructed into 16 items with 2 factors. This study also confirmed that the above reconstruction model is statistically suitable. The destructive leadership scale of Korean local police manager can be used as the basic data of leadership research to be conducted in the future.

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A Study on the Behavior of Deformation in Soft Soils Subjected to Lateral Flow (측방유동을 받는 연약지반의 변형거동에 관한 연구)

  • 안종필;홍원표
    • Geotechnical Engineering
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    • v.10 no.2
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    • pp.25-40
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    • 1994
  • In order to investigate behavior of lateral flow by plasticity of soils and construction control due to it, in the case of unsymmetrical surcharge load on the soft soils, we examine the existing theoretical background, and compared and analysed the experimental results by model test. After model test fabricated by model test apparatus, which made full remolding samples of soft soils, we observed the state of behavior for deformation with increasing load step to constant time interval. The critical surcharge and ultimate capacity showed tendency to approach to the proposed value of Jaky and Meyerhof, and the lateral flow pressure of which the maximum value was acted on the depth calculated by z/H=0.26+1.71cu and one third value of the maximum lateral flow pressure acted on the ground surface, approach the trapezoid distribution And maximum lateral flow pressure will be calculated by proposed equation of Hong or simple equation which($\alpha=0.4$) the flow pressure coefficient . of proposed equation by Tschebotarioff exchanged to($\alpha=K_0$) . Basides, the failure surcharge by [(q/$y_m$)-q] and [$S_y-(y_m/S_y)$] showed the smaller than ultimate bearing capacity, especially failure criteria line of control diagram of [$S_y(y_m/S_y)$] will be calculated by following equation. $S_y.=3.15exp[-0.58(y_m/S_y)$

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Allometric Equations of Crown Fuel Biomass and Analysis of Crown Bulk Density for Pinus densiflora (소나무 수관 부위별 연료량 추정식 개발 및 수관연료밀도 분석)

  • Lee, Byung-Doo;Won, Myoung-Soo;Kim, Seon-Young;Yoon, Suk-Hee;Lee, Myung-Bo
    • Journal of Korean Society of Forest Science
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    • v.99 no.3
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    • pp.391-396
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    • 2010
  • To analyze the characteristics of canopy fuel in Pinus densiflora stand, which is essential to assess the crown fire hazard, allometric equations for estimation of crown fuel biomass were developed by subjectively categorized crown fuel component and crown bulk density was analyzed by available fuel component categories. Ten trees were destructively sampled at Pinus densiflora stand in Mt. Palgong in Daegu and their crown fuels were weighed separately for each fuel category by size classes and by living and dead. Regression equations that estimate crown fuel load by diameter at breast height(D) or additional total height(H) were derived. The adjusted coefficient of determination values were the highest (${R^2}_{adj}$=0.835-0.996) and standard error of estimate were the lowest (SEE=0.074-0.638) in the allometric equation lnWt=${\alpha}+{\beta}lnD+{\gamma}lnH$ in average. However, in needles and small branches categories, the differences in ${R^2}_{adj}$ and SEE between equations were not significant. Crown bulk density (CBD), which was calculated by crown fuel load divided by crown volume, was 0.067 kg/$m^3$ in average when only needles were considered as available crown fuel and 0.097 kg/$m^3$ when needles and branches (0-0.5 cm diameter) were considered. The increments of CBD of needles and small branches were little even when diameter at breast height increased.

Assessment of Canopy Fuel Characteristics for Five Major Coniferous Species in Korea (우리나라 주요 침엽수종의 수관층 연료특성 평가)

  • Kim, Sungyong;Jang, Mina;Lee, Byungdoo;Lee, Youngjin
    • Journal of Korean Society of Forest Science
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    • v.102 no.2
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    • pp.247-254
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    • 2013
  • The objective of this study was to assess the canopy fuel characteristics of five major coniferous species in Korea. This study was also developed allometric equations for the canopy fuel load and canopy base height of the major coniferous species using the allomeric equations of biomass developed by the Korea Forest Research Institute and the data from the $5^{th}$ National Forest Inventory. Among the major coniferous fuel types, Pinus koraiensis stands had the highest mean canopy bulk density, 0.34 kg/$m^3$, followed by Gangwon region Pinus densiflora stands 0.28 kg/$m^3$, Pinus thunbergii stands 0.24 kg/$m^3$, Pinus rigida stands 0.15 kg/$m^3$, Central region Pinus densiflora stands 0.12 kg/$m^3$ and Larix leptolepis stands 0.09 kg/$m^3$. The adjusted multiple coefficient of determination of the developed models ranged from 0.6321 to 0.9950 for canopy fuel load and 0.6390 to 0.8539 for canopy base height.

The Load Distribution Characteristics of Pile Group under Lateral Loading (수평력을 받는 무리말뚝의 하중분담특성)

  • Ahn, Byungchul;Oh, Sewook
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.3
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    • pp.17-22
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    • 2010
  • This paper analyzed the characteristics of p-multiplier and the load distribution of H-pile group installed in weathered soil under horizontal loading. The results of this study conducted in pile arrangement ($2{\times}3$, $3{\times}3$), the pile center to center spacing (2D, 4D, 6D), and soil density (relative density: 40%, 80%) were drawn as follows. As to the average horizontal loading applied to each pile in pile groups, the fewer number of piles was, the larger average horizontal resistance became. As the result of analysis on p-y curves of single piles and pile groups according to the pile distance and the soil density, as the pile spacing was increased from 2D to 6D, the interaction coefficients of pile group showed 0.85~0.94 (piles in the front row), 0.57~0.79 (piles in the middle row), and 0.60~0.71 (piles in the rear row) in the loose ground and showed 0.76~0.82 (piles in the front row), 0.58~0.73 (piles in the middle row), and 0.53~0.70 (piles in the rear row) in the dense ground. As above, the wider pile distance was, the larger interaction coefficient value was shown among piles. In addition, piles in the front row showed bigger interaction coefficients than that of piles in the middle and back row.

A Study on Self-Esteem, IADL, and Life Satisfaction in the Elderly (가정노인과 양로원노인의 자아존중감, 일상생활활동능력, 생활만족도에 관한 연구)

  • 김정선
    • Journal of Korean Academy of Nursing
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    • v.28 no.1
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    • pp.148-158
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    • 1998
  • This study was designed to identify degrees of self-esteem instrumental activities of daily living and life satisfaction in the elderly and to investigate the relationship between these factors thus contributing to effective nursing interventions to promote quality of life for both noninstitutionalized and institutionalized elderly. The subjects for this study included 130 noninstitutionalized and institutionalized elderly. The data were collected through personal interviews using a questionnaire, the time being from August 25 to September 7, 1997. The measurement tools were the Self-esteem Scale Developed by Rosenberg and translated by Jon, Byong Je (1974). the IADL scale develped by Lawton & Brody(1968). and the Life Satisfaction developed by Youn. Jin(1982).The data were analyzed by the S.P. S.S computer progam and included descriptive stasistics, t-test, One way ANOVA and Pearson correlation coefficient. The conclusions of this study are summerized as follows ; 1. There was a significant difference in Self-Esteem(t=7.05, P=.000). IADL(t=4.36, P=.000). and Life Satisfaction(t=6.63, P=.000) between the noninstitutionalized elderly and the institutionalized elderly. 2. There was a significant positive correlation between self-esteem and IADL(${\gamma}$=.4028). self-esteem and life satisfaction(${\gamma}$=.6415). and IADL and life satisfaction(${\gamma}$=.3884) in the noninstitutionalized elderly(P<.001). and between self-esteem and life satisfaction(${\gamma}$=.3883, P<.001). IADL and life satisfation(${\gamma}$=.2501, P<.05) in the institutionalized elderly. 3. According to the general characteristics of the noninstitutionalized and institutionalized elderly : Self-Esteem of the noninstitutionalized elderly was significantly different. according to educational level(F=4.491, P=.031). job(F=2.53, P=.044). living expense load(F=2.861. P=.044). and self-esteem, and of the institutionalized elderly, it was significantly different according to educational level only (F=4.480, P=.006). IADL of the noninstitutionalized elderly was significantly different according to age(F=3.018, P=.021). living expense load(F=3.034. P=.033). pocket money(F=3.606. P=.010). and for the institutionalized elderly, it was significantly different according to age(F=2.899, P=.042), and religion(F=2.847, P=.044). Life Satisfaction of the noninstitutionaized elderly( F=2.718, P=.037) and instiutionalized elderly(F=3.165, P=.030) was significantly different according to pocket money.

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Development of Semi-basement Type Greenhouse Model for Energy Saving

  • Kim, Seoung Hee;Joen, Jong Gil;Kwon, Jin Kyeong;Kim, Hyung Kweon
    • Journal of Biosystems Engineering
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    • v.41 no.4
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    • pp.328-336
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    • 2016
  • Purpose: The heat culture areas of greenhouses have been continuously increasing. In the face of international oil price fluctuations, development of energy saving technologies is becoming essential. To save energy, auxiliary heat source and thermal insulation technologies are being developed, but they lack cost-efficiency. The present study was conducted to save energy by developing a conceptually new semi-basement type greenhouse. Methods: A semi-basement type greenhouse, was designed and constructed in the form of a three quarter greenhouse as a basic structure, which is an advantageous structure to inflow sunlight. To evaluate the performance of the developed greenhouse, a similar structured general greenhouse was installed as a control plot, and heating tests were conducted under the same crop growth conditions. Results: Although shadows appeared during the winter in the semi-basement type greenhouse due to the underground drop, the results of crop growth tests indicated that there were no differences in crop growth and development between the semi-basement type greenhouse and the control greenhouse, indicating that the shadows did not affect the crop up to the height of the crop growing point. The amount of fuel used for heating from January to March was almost the same between the two greenhouses for tests. The heating load coefficients of the experimental greenhouses were calculated as $3.1kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the semi-basement type greenhouse and $2.9kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the control greenhouse. Since the value is lower than the double layer PE (polyethylene) film greenhouse value of $3.5kcal/m^2{\cdot}^{\circ}C{\cdot}h$ from a previous study, Tthe semi-basement type greenhouse seemed to have energy saving effects. Conclusions: The semi-basement type greenhouse could be operated with the same fuel consumption as general greenhouses, even though its underground portion resulted in a larger volume, indicating positive effects on energy saving and space utilization. It was identified that the heat losses could be reduced by installing a thermal curtain of multi-layered materials for heat insulation inside the greenhouse for the cultivation of horticultural products by installing thermal curtain of multi-layered materials for heat insulation inside the greenhouse, it was identified that the heat losses could be reduced.

Evaluation of Lateral Load Resistance and Heating/Cooling/Lighting Energy Performance of a Post-disaster Refugees Housing Using Lightweight composite Panels (경량 복합패널을 활용한 구호주거의 횡하중 저항성능 및 냉난방조명 에너지성능 평가)

  • Hwang, Moon-Young;Lee, Byung-Yun;Kang, Su-Min;Kim, Sung-Tae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.3
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    • pp.252-262
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    • 2019
  • Following the earthquake in Gyeongju (2016) and Pohang (2017), South Korea is no longer a safe place for earthquakes. Accordingly, the need for shelters suitable for disaster environments is increasing. In this study, a lightweight composite panel was used to produce post-disaster housing for refugees to compensate for the disadvantages of existing evacuation facilities. For this purpose, an evaluation of structural performance and thermal environment for post-disaster housing for refugees composed of lightweight composite panels was performed. To assess the structural performance, a lateral loading test was conducted on a system made of lightweight composite panels. The specimens consisted of two types, which differed according to the bonding method, as a variable. In addition, the seismic and wind loads were calculated in accordance with KBC 2016 and compared with the experimental results. Regarding the energy performance, optimization of south-facing window planning and window-wall ratio and solar heat gain coefficient were analyzed to minimize heating, cooling, and lighting energy. As a result, the specimens composed of lightweight composite panels will perform sufficiently safely for lateral loads and the optimized window planning will lead to a low-energy operation.

Estimation of Resistance Bias Factors for the Ultimate Limit State of Aggregate Pier Reinforced Soil (쇄석다짐말뚝으로 개량된 지반의 극한한계상태에 대한 저항편향계수 산정)

  • Bong, Tae-Ho;Kim, Byoung-Il;Kim, Sung-Ryul
    • Journal of the Korean Geotechnical Society
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    • v.35 no.6
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    • pp.17-26
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    • 2019
  • In this study, the statistical characteristics of the resistance bias factors were analyzed using a high-quality field load test database, and the total resistance bias factors were estimated considering the soil uncertainty and construction errors for the application of the limit state design of aggregate pier foundation. The MLR model by Bong and Kim (2017), which has a higher prediction performance than the previous models was used for estimating the resistance bias factors, and its suitability was evaluated. The chi-square goodness of fit test was performed to estimate the probability distribution of the resistance bias factors, and the normal distribution was found to be most suitable. The total variability in the nominal resistance was estimated including the uncertainty of undrained shear strength and construction errors that can occur during the aggregate pier construction. Finally, the probability distribution of the total resistance bias factors is shown to follow a log-normal distribution. The parameters of the probability distribution according to the coefficient of variation of total resistance bias factors were estimated by Monte Carlo simulation, and their regression equations were proposed for simple application.

Using Topology Optimization, Light Weight Design of Vehicle Mounted Voltage Converter for Impact Loading (위상 최적화 기법을 이용한 충격하중에 대한 차량 탑재형 전력변환장치의 마운트 경량화 설계)

  • Ko, Dong-Shin;Lee, Hyun-Kyung;Hur, Deog-Jae
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.31 no.6
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    • pp.353-358
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    • 2018
  • In this study, it is describe to an optimization analysis process for the weight reduction of the voltage converter in the electric vehicle charging systems. The optimization design is a technique that finds the optimal material distribution under a given material quantity constraint by combining the design sensitivity with the material properties and the mathematical optimization. Among the topology optimization, a lightweight design is performed by a solid isotropic material with penalization with simple formula and well-convergence. The lightweight design consists of three steps. As a first step, a finite element model for the basic design of the on-board voltage converter was constructed and static analysis was performed on the load. In the second step, the optimum shape is obtained for the lightweight by performing the topology optimization using the solid isotropic material with penalization applying the stiffness coefficient of the isotropic material to the static analysis result. As a final step, impact analysis was performed by applying a half-sinusoidal pulse shape impact load which satisfies the impact test standard of the vehicle-mounted part with respect to the optimum shape. In the topology optimization, the design domain was defined as the mounting bracket area, and the design technology was finally achieved by optimizing the mounting bracket to achieve a weight reduction of 20% over the basic design.