• International Commerce and Information Review
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• v.12 no.4
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• pp.171-192
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• 2010

In general, a stock index and its individual stocks are assumed to follow a random walk. A stock index is an important source of information and one that is seen by people everyday, regardless of their investment intentions. This paper examines the correlation between the KOSPI-the index that best reflects the Korean stock market and the macro - economic variables that have been found to influence the index by previous studies. The sample period considers the years after 2000 when the Korean stock market matured as restrictions on foreign investors were removed. For this purpose, a Vector Error Correction Model (VECM) and KOSPI equation with a general pacific approach were used. This paper aims at verifying the factors that determined the KOSPI after 2000 and at examining whether there was structural change in the investment environment. It also investigates changes in the factors determining the KOSPI's performance as a result of structural changes in the investment environment. The V AR (Vector Autoregressive) model including the nine variables was selected as a baseline model whose stability was tested using the unit root test. The results from the VECM and the structural changes in the investment environment can be summarized by the following Inner story points.

• Journal of Korean Academy of Nursing Administration
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• v.15 no.3
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• pp.305-313
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• 2009

Purpose: This study was done to identify the current status of burnout research on Korean nurses and to suggest the directions for future research. Method: Fifty two articles between 1998 and 2007 were selected using the key words such as "Nurse" and "Burnout" from the database (RISS4U et al.). Results: 77.9% of studies were master's theses unpublished in the nursing journals. All studies were cross-sectional and therefore did not allow casual inference. Hospital nurses were the most common subjects (21 studies). The most frequently used burnout measurement instrument was the Burnout Measure, while the Maslach Burnout Inventory was used in only 6 studies. 55.7% of studies reported the average burnout score as higher than the middle level. Among individual factors, variables significantly correlated to burnout were age, position, work experience, coping, and personality. Some of job factors including shift work, workloads, job stress, and organizational commitment were also significantly related to burnout. There was very little discussion about the influence of organizational factors analyzed by unit or institution level. Conclusion: In Korea, the next phase of nurse burnout research needs to consider the measurement tool selection for the international comparison and longitudinal design to find more specific causal relationships.

• Journal of Advanced Navigation Technology
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• v.13 no.6
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• pp.964-970
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• 2009

In this paper, according to the company's business objectives through the execution plan of project-specific progress and to achieve effective management of performance management in conjunction with a project management system can be developed. Goal-based Medium Enterprises Sized project performance management system eophyeong advancement of the strategic project management and corporate performance management for the systematic integration and implementation of an individual were to be applied. Organizations to perform a systematic strategy to manage the administration transparent, objective, you evaluate, say he reflects the integration and implementation of management systems between organizations and the unit responsible for the detailed performance indicators and grant to refine your business can benefit there is.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.8 no.1
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• pp.1-11
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• 1983

The object of this paper is to investigate a PCM telemetry system which is designed and constructed in individual modules for an airborne remote measurement system for the first time in Korea. The time division multiplexing PCM encoder has maximum allowable input channels 64 words/frame, 140kbits/sec bit rate. 200frames/sec and 10 bits/wod resolution. And the transmitting unit is designed for 2.2-2.3GHz(s-band) telemetry frequency band, PCM/FM modulation. The Study of airborne PCM telemtry system contribute to develop a device which can acquire various technical data of newly developing flying vehicles by remote measurement. The performance of the proposed system has been verified through a seguence of tests.

• Korean Institute of Interior Design Journal
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• v.17 no.5
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• pp.141-149
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• 2008

This study aims to understand functional spaces within university dormitory, examine the influences of residential environment factors and personal characteristics on users' satisfaction through what parameters and probability among these parameters and seek improvement methods for dormitory users to live at dormitory as the best residential space through causal analysis of residential space uses at university dormitory based on such a probability. Research methods include theoretical research of architectural space characteristics of university dormitory facilities through literature survey, analysis of satisfaction with spaces and their uses through questionnaire and causal analysis of each residential environment factor after making route model using data obtained from the results of analysis. The results of this study are as follows. Factors affecting residents' satisfaction with cultural activities of residential environment factors are safety, territoriality, interior finishing and complexity and those affecting residents' educational activities are safety and amenity of space. Residential function space of university dormitory must have spatial planning that social activities including individual and small group culture and educational activities from the view of spatial territoriality and flexibility based on safety and amenity and facilities related to continuity and connection of common space and unit residential space should be decentralized rather than centralized.

• Journal of Electrical Engineering and Technology
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• v.9 no.1
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• pp.239-246
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• 2014

Incineration is conceptually sound as a waste treatment technology. There is, however, concern over its emissions when it is improperly designed and operated. An electrostatic precipitator is one of the most commonly used devices to control particulate emissions from boilers, incinerators and some other industrial processes. In this work, a modular electrostatic precipitator with sizing of $1m{\times}1m{\times}1m$ was developed for removal of particulate matter from the exhaust gases of a small waste incinerator. Its design was based on a simple wire-and-plate concept. The corona discharge wires were connected to a positive high-voltage pulse generator, while the collection plates were grounded. The high-voltage pulse generator was used to produce the corona discharge field between the individual discharge wire and the collection plate. The particulate-laden exhaust gas flow was directed across the corona discharge field. The charged particles were deflected outward and collected on the plate. The collection efficiency was evaluated as a mass loading ratio between the difference at the inlet and the outlet to the particulate loading at the inlet of the precipitator. The collection efficiency of this modular electrostatic precipitator design was approximately 80 %.

• Journal of Power Electronics
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• v.17 no.5
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• pp.1308-1316
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• 2017

The distributed maximum power point tracking (DMPPT) concept is widely adopted in photovoltaic systems to avoid mismatch loss. However, the high cost and complexity of DMPPT hinder its further promotion in practice. Based on the concept of DMPPT, this paper presents an integrated submodule level half-bridge stack structure along with an optimal current point tracking (OCPT) control algorithm. In this full power processing integrated solution, the number of power switches and passive components is greatly reduced. On the other hand, only one current sensor and its related AD unit are needed to perform the ideal maximum power generation for all of the PV submodules in any irradiance case. The proposal can totally eliminate different small-scaled mismatch effects in real-word condition and the true maximum power point of each PV submodule can be achieved. As a result, the ideal maximum power output of the whole PV system can be achieved. Compared with current solutions, the proposal further develops the integration level of submodule DMPPT solutions with a lower cost and a smaller size. Moreover, the individual MPPT tracking for all of the submodules are guaranteed.

• Journal of Animal Environmental Science
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• v.19 no.2
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• pp.141-148
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• 2013

This study was conducted to evaluate the effect of different housing systems on the performances of sows and their piglets during gestation. A total of 90 sows (Landrace ${\times}$ Yorkshire) were employed into 3 experimental farms to give 3 treatments, stall housing, group housing in either slatted floor or litter floor. Individual sow was used as an experimental unit. Group housed sows were fed with electronic sow feeder during gestation. Performance measures were taken on sows and piglets. Back-fat thickness and body condition score of sows were not affected by housing systems for pregnant sows. There was no difference of estrus interval of pregnant sows between housing systems. The lower number of still-birth was observed in group housing type. The number of wounded sows in slatted floor was remarkably increased compared with sows in litter floor. This study showed that the housing systems could fairly impact sow and piglet performances.

• Tribology and Lubricants
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• v.36 no.5
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• pp.290-296
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• 2020

When two layers of carbon nanotube (CNT) arrays are loaded to mate, the free ends of individual CNTs come into contact at the interface of the two layers. This leads to a higher contact resistance due to a smaller contact region. However, when the free CNT ends of one array penetrate into the mating array, the contact region increases, effectively lowering the contact resistance. To explore the penetration of mating CNTs, we perform molecular dynamic simulations of a simple unit cell model, incorporating four CNTs in the lower array layer coupled with a single moving CNT on the upper layer. The interaction with neighboring CNTs is modelled by long-range carbon bond order potential (LCBOP I). The model structure is optimized by energy minimization through the conjugate gradient method. A NVT ensemble is used for maintain a room temperature during simulation. The time integration is performed through the velocity-Verlet algorithm. A significant vibrational motion of CNTs is captured when penetration is not available, resulting in a specific vibration mode with a high frequency. Due to this vibrational behavior, the random behaviors of CNT motion for predicting the penetration are confirmed under the specific gap distances between CNTs. Thus, the probability of penetration is examined according to the gap distance between CNTs in the lower array and the aspect ratio of CNTs. The penetration is significantly affected by the vibration mode due to the van der Waals forces between CNTs.

• Proceedings of the Korean Society of Crop Science Conference
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• 2005.08a
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• pp.100-113
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• 2005

Leaf color and plant vigor are key indicators of crop health. These visual plant attributes are frequently used by greenhouse managers, producers, and consultants to make water, nutrient, and disease management decisions. Remote sensing techniques can quickly quantify soil and plant attributes, but it requires humans to translate such data into meaningful information. Over time, scientists have used reflectance data from individual wavebands to develop a series of indices that attempt to quantify things like soil organic matter content, leaf chlorophyll concentration, leaf area index, vegetative cover, amount of living biomass, and grain yield. The recent introduction of active sensors that function independent of natural light has greatly expanded the capabilities of scientists and managers to obtain useful information. Characteristics and limitations of active sensors need to be understood to optimize their use for making improved management decisions. Pot experiments involving sand culture were conducted in 2003 and 2004 in a green house to evaluate corn and red pepper biomass. The rNDVI, gNDVI and aNDVI by ground-based remote sensors were used for evaluation of corn and red pepper biomass. The result obtained from the case study was shown that ground remote sensing as a non-destructive real-time assessment of plant nitrogen status was thought to be a useful tool for in season crop nitrogen management providing both spatial and temporal information.