• Structural Engineering and Mechanics
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• v.23 no.1
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• pp.63-74
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• 2006

In this paper, the scattering of harmonic elastic anti-plane shear waves by two collinear cracks in functionally graded materials is investigated by means of nonlocal theory. The traditional concepts of the non-local theory are extended to solve the fracture problem of functionally graded materials. To overcome the mathematical difficulties, a one-dimensional non-local kernel is used instead of a two-dimensional one for the anti-plane dynamic problem to obtain the stress field near the crack tips. To make the analysis tractable, it is assumed that the shear modulus and the material density vary exponentially with coordinate vertical to the crack. By use of the Fourier transform, the problem can be solved with the help of a pair of triple integral equations, in which the unknown variable is the displacement on the crack surfaces. To solve the triple integral equations, the displacement on the crack surfaces is expanded in a series of Jacobi polynomials. Unlike the classical elasticity solutions, it is found that no stress singularities are present at crack tips.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2009.05a
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• pp.168-171
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• 2009

High-frequency induction is an efficient way to heat mold surface by electromagnetic induction in a non-contact procedure. Though the induction heating has an advantage in terms of its rapid-heating capacity on the mold surface, it still has a restriction on mold temperature control due to geometric restriction of an induction coil according to the mold shape. It has been recently applied to the injection molding of thin-walled parts or micro/nano structures. For localized induction heating, an injection mold composed of ferromagnetic material and paramagnetic material is used. The electromagnetic induction concentrates on the ferromagnetic material, from which we can selectively heat for the local mold elements. The present study proposed a localized induction heating method by means of selective use of mold material. The feasibility of the proposed heating method is investigated through the comparison of experimental observations according to the mold material.

• Journal of the Korean Dietetic Association
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• v.8 no.2
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• pp.185-198
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• 2002

The purpose of this study was to compare food habits and nutrient intakes with body mass index of hypertensive patients commuting to a Local Health Center. A total of 85 patients were divided into two groups according to BMI. The non-obese group comprised 43 subjects with BMI below 25㎏/$m^2$ , while the obese group comprised 42 subjects with BMI above 25㎏/$m^2$ . All Subjects were interviewed for general characteristics, food habits, clinical characteristics, effort for health maintenance and the knowledge of hypertension and nutrition. Anthropometric assessments such as weight, height, waist-hip ratio and biochemical measurement of blood urea nitrogen, creatinine, triglyceride, total cholesterol, HDL-cholesterol and fasting blood glucose(FBG) were obtained from subjects. In general characteristics, smoking, drinking, exercise, and hypertension status were not significantly different between the two groups. Food habits and the means of daily energy and nutrients were not significantly different between the two groups. An analysis of the percentage of RDA(Recommended Dietary Allowances of Korea, 2000) consumed by patients showed that but for ascorbic acid and phosphorus, all nutrients were below the RDA. And intakes of vitamin $B_1$(P<0.001), vitamin $B_2$(P<0.01), niacin(P<0.001) of the obese group were significantly lower than that of the non-obese group. Blood urea nitrogen, creatinine, triglyceride, total cholesterol, HDL-cholesterol and fasting blood glucose were in the normal range and there was not a significant difference in the two groups. Therefore, more effective nutrition education programs about exercise, smoking, caloric intake, vitamins and minerals are required for hypertensive patients commuting to Local Health Center.

• Korean Journal of Remote Sensing
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• v.33 no.1
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• pp.89-95
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• 2017

Ship detection in synthetic aperture radar(SAR)imagery has long been an active research topic and has many applications. In this paper,we propose an efficient method for detecting ships from SAR imagery using filtering. This method exploits ship masking using a median filter that considers maximum ship sizes and detects ships from the reference image, to which a Non-Local means (NL-means) filter is applied for speckle de-noising and a differential image created from the difference between the reference image and the median filtered image. As the pixels of the ship in the SAR imagery have sufficiently higher values than the surrounding sea, the ship detection process is composed primarily of filtering based on this characteristic. The performance test for this method is validated using KOMPSAT-5 (Korea Multi-Purpose Satellite-5) SAR imagery. According to the accuracy assessment, the overall accuracy of the region that does not include land is 76.79%, and user accuracy is 71.31%. It is demonstrated that the proposed detection method is suitable to detect ships in SAR imagery and enables us to detect ships more easily and efficiently.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.328-330
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• 2015

Edge is a characteristic information that can easily obtain the size, direction and location of objects included in the image, and the edge detection is utilized as a preprocess processing in various image processing application sectors such as object detection and object recognition, etc. For the conventional edge detection methods, there are Sobel, Prewitt and Roberts. These existing edge detection methods are easy to implement but the edge detection characteristics are somewhat insufficient as fixed weighted mask is applied. Therefore, in order to compensate the problems of existing edge detection methods, in this paper, an edge detection algorithm was proposed after applying the weighted value according to the standard deviation and means within the local mask.

• Journal of Distribution Science
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• v.22 no.6
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• pp.69-81
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• 2024

Purpose: Small airports are social and economic enablers and facilitate businesses and individuals. They contribute significantly to the distribution and logistics of the local produce - be it goods or services, thereby impacting the economy but have limited access to funds and poor management restricts their development. Despite the importance, small airports in small cities struggle financially as they are unable to earn profits and have higher operating costs. In other words, this is a paradoxical situation for small airports wherein, despite losses, the regional or national public authorities still finance such airports under socio-economic obligations. Therefore, this study aims to identify the critical success factors for improving small airports' performance and propose a business model. Research design, data and methodology: Using the qualitative research, interviews with 16 stakeholders from Guwahati, Tirupati, Bhubaneswar and Dehradun airports in india were examined. Results: The analysis reveals strategic planning and low cost, non-passenger services, and development of airport economic region as the main factors contributing towards small airports' success. Additionally, providing logistics to the local businesses and creating niche markets are suggested. Conclusions: Small airports, based on their services and the means of targeting customers, could select the relevant approach to improve their overall performance and improve profitability.

• Korean Association of Arts Management
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• no.49
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• pp.149-176
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• 2019

It is a known fact that the spread of multiplexes has contributed to movie industry flourish and extending public rights for enjoying movies. However, in terms of Urban Discourse, Multiplexes centered in new downtown have given rise to Doughnut Phenomena in old downtown. It is especially regrettable that the local theaters which have been symbolic cultural spaces storing the 'memory of life' of local communities are disappearing due to a recession of business zone in old downtown. Japan has long been worked in various activities spotlighting on movie/image contents as the major means of creative urban regeneration. Among them, the 'Community Cinema' has made a contribution to regional revitalization by improving movie screening environment of the local community through renewal of local theaters and further creating related culture and industry in the local area. In this study, I focus on 'Fukaya Cinema' which started from NPO(Non-Profit Organization) and reused a closed industrial facility to a movie theater in cooperation with local TMO(Town Management Organization). Fukaya Cinema, which operates in the form of a business community, plays important roles as the core cultural facility in the local community and is regarded as a significant case showing a possibility of urban regeneration using movie/image contents. I investigate the specific founding process and activities of Fukaya Cinema and intend to derive the implications from that. Through this, I aim to provide the basic urban regeneration data utilizing movie/media contents.

• Journal of the Korean Magnetics Society
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• v.12 no.1
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• pp.20-23
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• 2002

The local coercivity distribution of CoCrPt alloy films prepared by dc magnetron sputtering has been investigated by means of a magneto-optical microscope magnetometer (MOMM) capable of simultaneously measuring the local properties on 400 nm spatial resolutions. Serial samples of CoCrPt alloy films were prepared with the Pt composition of a range from 6 to 28 at. %. We find that the local coercivity distribution crosses over from Gaussian to non-Gaussian distribution in CoCrPt alloy films with increasing Pt composition, with increasing trends in the width of the distribution as well as the average local coercivity. Transmission electron microscopy (TEM) studies reveal that our findings are closely correlated with the dependences of the grain size distribution and its average size on Pt concentration.

• The Korean Journal of Emergency Medical Services
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• v.10 no.1
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• pp.13-21
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• 2006

Purpose: This study aims to examine characteristics and actual conditions of patients using emergency room at farming and fishing villages, solve overcrowding of emergency room at the tertiary hospital and activate local emergency clinics. Methods: It examines department of diagnosis and treatment, vehicles used, sex, age, residential area, visit hour, length of stay, presence or absence of trauma, measures after first aid and degree of severity based on medical records of 6,740 patients using emergency room at farming and fishing villages from Jan. 1 to Dec. 31, 2005. Conclusion : 1. Sex distribution of patients of emergency room was male 54.9% and female 45.1% and age distribution between over 40 and below 50 was most as 15.9%. 2. Transport means to emergency room were 91.4 of private car and others (public transport and going on foot), 7.5 of 119, 129 and police car and 1.0% of ambulance. 3. According to distribution of residential areas of emergency patients, 38.9% were Eup area, 42.1% Myeon area, 11.4% distant area and 7.5% adjacent area. 4. According to distribution of emergency patients by department of diagnosis and treatment, internal medicine was most as 35.8% and 55% of patients visited emergency room from 3:31 p.m. to 11:30 p.m.. 5. According to total hours of diagnosis and treatment of subjects, 51.2% were within 30min. and cases of non-trauma disease were 68.2%. 6. According to degree of emergency of emergency patients, non-emergency cases were 65.3%, urgent cases 27.7% and emergency cases 7.0% and 74.2% of patients returned home after first aid and 20.6% of them hospitalized. In conclusion, characteristics and diversification of patients should be examined and efforts by government and local medical institutions which must organize emergency system and facility and personnel levels suitable to regional conditions are needed in order to prevent overcrowding of emergency center of the tertiary hospital and activate local emergency center.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.34 no.1
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• pp.43-52
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• 2016

Due to the characteristics of microwave signals, Radar satellite image has been used for flood detection without weather and time influence. The more methods of flood detection were developed, the more detection rate of flood area has been increased. Since flood causes a lot of damages, flooded area should be distinguished from non flooded area. Also, the detection of flood area should be accurate. Therefore, not only image resolution but also the filtering process is critical to minimize resolution degradation. Although a resolution of radar images become better as technology develops, there were a limited focused on a highly suitable filtering methods for flood detection. Thus, the purpose of this study is to find out the most appropriate filtering method for flood detection by comparing three filtering methods: Lee filter, Frost filter and NL-means filter. Therefore, to compare the filters to detect floods, each filters are applied to the radar image. Comparison was drawn among filtered images. Then, the flood map, results of filtered images are compared in that order. As a result, Frost and NL-means filter are more effective in removing the speckle noise compared to Lee filter. In case of Frost filter, resolution degradation occurred severly during removal of the noise. In case of NL-means filter, shadow effect which could be one of the main reasons that causes false detection were not eliminated comparing to other filters. Nevertheless, result of NL-means filter shows the best detection rate because the number of shadow pixels is relatively low in entire image. Kappa coefficient is scored 0.81 for NL-means filtered image and 0.55, 0.64 and 0.74 follows for non filtered image, Lee filtered image and Frost filtered image respectively. Also, in the process of NL-means filter, speckle noise could be removed without resolution degradation. Accordingly, flooded area could be distinguished effectively from other area in NL-means filtered image.