• Journal of the Korean Geographical Society
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• v.40 no.2 s.107
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• pp.221-241
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• 2005

Land Use and Land Cover Changes (LUCC) occur over a wide range of space and time scales, and involve complex natural, socio-economic, and institutional processes. Therefore, modelling and predicting LUCC demands an understanding of how various measured properties behave when considered at different scales. Understanding spatial and temporal variability of driving forces and constraints on LUCC is central to understanding the scaling issues. This paper aims to 1) assess the heterogeneity of land cover change processes over the landscape in northern Ghana, where intensification of agricultural activities has been the dominant land cover change process during the past 15 years, 2) characterise dominant land cover change mechanisms for various spatial scales, and 3) identify the optimal spatial scale for LUCC modelling in a savanna landscape. A multivariate statistical method was first applied to identify land cover change intensity (LCCI), using four time-sequenced NDVI images derived from LANDSAT scenes. Three proxy land use change predictors: distance from roads, distance from surface water bodies, and a terrain characterisation index, were regressed against the LCCI using a multi-scale hierarchical adaptive model to identify scale dependency and spatial heterogeneity of LUCC processes. High spatial associations between the LCCI and land use change predictors were mostly limited to moving windows smaller than 10$\times$10km. With increasing window size, LUCC processes within the window tend to be too diverse to establish clear trends, because changes in one part of the window are compensated elsewhere. This results in a reduced correlation between LCCI and land use change predictors at a coarser spatial extent. The spatial coverage of 5-l0km is incidentally equivalent to a village or community area in the study region. In order to reduce spatial variability of land use change processes for regional or national level LUCC modelling, we suggest that the village level is the optimal spatial investigation unit in this savanna landscape.

• Journal of Korean Academy of Nursing
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• v.45 no.2
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• pp.202-210
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• 2015

Purpose: The purpose of this study was to describe depression, caregiving burden and the correlation of the two variables in the families of patients with amyotrophic lateral sclerosis (ALS) and to clarify factors predicting caregiving burden. Methods: A descriptive and cross-sectional study was conducted with 139 family members who provided care to patients with ALS. The characteristics of patients and families, Korean-Beck Depression Inventory (K-BDI), Korean version of Zarit Burden Interview (K-ZBI) and Korean-Amyotrophic Lateral Sclerosis Functional Rating Scale - Revised (K-ALSFRS-R) were used as study measures. Results: The mean score for K-BDI was 19.39 out of 63 suggesting sub-clinical depression and 38.2% of the family members exhibited depression. The mean score for K-ZBI was 66.03 out of 88. The predictors for K-ZBI were K-BDI, age of family member, length of time spent per day in caring, relationship to patient and K-ALSFRS-R. Conclusion: The results of this study suggest that levels of depression and caregiving burden are high among family members caring for patients with ALS. As depression is associated with caregiving burden, screening and emotional supports should be provided to reduce the burden of care for these family. Support programs to alleviate the care burden are also needed, considering family demographics, time per day in caring giving and K-ALSFRS-R.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.2
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• pp.163-169
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• 2012

A decrease in pass ratio of Korean exporting pears causes several negative effects including an increase in pesticide dependency. In this study, we attempted to establish the pest forecasting management system, composed of weekly field forecasting by pear farmers, meteorological data obtained by automatic weather station (AWS), newly designed internet web page ($\underline{http://pearpest.jnu.ac.kr/}$) as information collecting and providing ground, and information providing service. The weekly field forecasting information on major pear diseases and pests was collected from the forecasting team composed of five team leaders from each pear exporting complex. Further, an abridged weather information for the prediction of an infestation of major disease (pear scab) and pest (pear psylla and scale species) was obtained from an AWS installed at Bonghwang in Naju City. Such information was then promptly uploaded on the web page and also publicized to the pear famers specializing in export. We hope this pest forecasting management system increases the pass ratio of Korean exporting pears throughout establishment of famer-oriented forecasting, inspiring famers' effort for the prevention and forecasting of diseases and pests occurring at pear orchards.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.88-92
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• 2020

Thermal effects in bulk and SOI FinFETs are briefly reviewed herein. Different techniques to measure these thermal effects are studied in detail. Self-heating effects show a strong dependency on geometrical parameters of the device, thereby affecting the reliability and performance of FinFETs. Mobility degradation leads to 7% higher current in bulk FinFETs than in SOI FinFETs. The lower thermal conductivity of SiO₂ and higher current densities due to a reduction in device dimensions are the potential reasons behind this degradation. A comparison of both bulk and SOI FinFETs shows that the thermal effects are more dominant in bulk FinFETs as they dissipate more heat because of their lower lattice temperature. However, these thermal effects can be minimized by integrating 2D materials along with high thermal conductive dielectrics into the FinFET device structure.

• Journal of the Korea Society of Computer and Information
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• v.20 no.5
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• pp.91-98
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• 2015

In this paper, we introduce PMS's main function and main effect which implemented medium and large scale software development project site, and we propose importance and improvement nacessity of PMS implementation. PMS's main functions are developed based on best practices which CMMI model and PMBOK. Also, each PMS has specialized unique function according to it's target industry area or related I.T solutions which has infra dependency. The effectiveness of PMS implementation on project site is seperated two types, one is qualitative effect, the other quantitative effect. Representative qualitative effects are improvement of enterprise's image and competency. Also representative quantitative effect is reduction of project management cost as a financial effect. As far as project size is increase, PMS's needs and necessariness will be increase, so we need to improve PMS;s function according to project management's global trend and software customer's requisition.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.47 no.3
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• pp.83-89
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• 2010

Scalable routing is one of the key challenges in designing and operating large scale MANETs. Performance of routing protocols proposed so far is only guaranteed under various limitation, i.e., dependent of the number of nodes in the network or needs the location information of destination node. Due to the dependency to the number of nodes in the network, as the number of nodes increases the performance of previous routing protocols degrade dramatically. We propose Cluster Overlay Dynamic Source Routing (CODSR) protocol. We conduct performance analysis by means of computer simulation under various conditions - diameter scaling and density scaling. Developed algorithm outperforms the DSR algorithm, e.g., more than 90% improvement as for the normalized routing load. Operation of CODSR is very simple and we show that the message and time complexity of CODSR is independent of the number of nodes in the network which makes CODSR highly scalable.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.24 no.4
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• pp.721-737
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• 2014

The Resident Registration Number(RRN) system has been effectively acted as a national identification system since it was enforced. On the other hand, there are some problems such as leakages of personal informations including RRNs on a large scale and each RRN makes a pair with each person in all areas of the society. Nevertheless leakages of them might cause a big damage, there is no radical countermeasure for they are never changed in actual fact. In Republic of Korea, a RRN acts as a primary key of a database, so it has to be protected by severing the connectivity between leaked RRNs and the other personal data. In this paper, the Unconnected Random Personal Identification Number system is proposed for preventing damage of data spills by removing a dependency which the RRN has. Furthermore, this paper suggests the solutions against some potential issues in the system.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.16 no.4
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• pp.407-417
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• 2003

Enen though several GA-based optimization algorithms have been successfully applied to complex optimization problems in various engineering fields, GA-based optimization methods are computationally too expensive for practical use in the field of structural optimization, particularly for large- scale problems. Furthermore, a successful implementation of GA-based optimization algorithm requires a cumbersome and trial-and-error routine related to setting of parameters dependent on a optimization problem. Therefore, to overcome these disadvantages, a high-performance GA is developed in the form of distributed hybrid genetic algorithm for structural optimization on a cluster of personal computers. The distributed hybrid genetic algorithm proposed in this paper consist of a simple GA running on a master computer and multiple μ-GAs running on slave computers. The algorithm is implemented on a PC cluster and applied to the minimum weight design of steel structures. The results show that the computational time required for structural optimization process can be drastically reduced and the dependency on the parameters can be avoided.

• Journal of the Semiconductor & Display Technology
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• v.18 no.3
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• pp.77-81
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• 2019

Recently, Korea has been making efforts at the government level to overcome the national crisis that Japan's dependency on technology in the semiconductor and display materials sectors has also escaped due to export regulations on three materials carried out by Japan. Therefore, based on the data of the National Science & Technology Information Service (NTIS) operated by the government, we analyze the trend of R & D investment in the display field, thereby improving R & D to improve material technology competitiveness in the future. Let's examine the implications of investment. A total of 5 years of new research and development investment in the field of display was invested as basic research fund for 25%, 15% for applied research, and 53% for development research. In terms of development cost and development period, the basic research showed that the amount of money and the development period were shorter than that of applied research. In other words, the basic research accounted for 25% of the R & D investment and the average R & D period was only 3.2 years. As we can see from the recent development of H fiber carbon fiber, which was recently developed and entered full-scale production, we were able to succeed because of the benefits of government support for 10 years while giving the same material title differently. In order to escape from Japan's technological dependence on semiconductor and display materials in Korea, As such, basic research in the field of materials is only possible when long-term research is conducted.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.14-19
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• 2005

One area in which composites have been used rather extensively is for fabricating pressure vessel. These structures can be readily manufactured by filament winding, which is, as far as composite fabrication techniques are concerned, a relatively inexpensive method for producing composite structures. Unfortunately, the higher strength material and fabrication costs are not the only disadvantages of fiber-reinforced polymer composites when they are compared to metals. Additionally, these materials tend to exhibit brittle behavior. This is of particular concern when they are subjected to a low-velocity impact during routine handling a significant amount of structural damage can be introduced into the composites. The goals of this paper are to understand the impact damage behavior and identify the effect of surface coating materials on impact resistance in filament wound composite pressure vessels. For these, a series of low velocity impact tests was performed on specimens cutting from the full scale pressure vessel by the instrumented impact testing machine. The specimens are classified into two types with and without surface protective material. The visualization for impact damage is made by metallurgical microscope. Based on the impact force history and damage, the resistance parameters were employed and its validity in identifying the damage resistance of pressure vessel was reviewed. As the results, the impact resistance of the filament wound composites and its dependency on the protective material were evaluated quantitatively.