• Composites Research
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• v.19 no.5
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• pp.28-33
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• 2006

In this paper, we have studied the complex permittivities and their influence on the design of microwave absorbers of E-glass fabric/epoxy composite laminates containing three different types of carbon-based nano conductive fillers such as carbon black (CB), carbon nano fiber (CNF) and multi-wall nano tube (MWNT). The measurements were performed fur permittivities at the frequency band of 0.5 GHz$\sim$18.0 GHz using a vector network analyzer with a 7 mm coaxial air line. The experimental results show that the complex permittivities of the composites depend strongly on the natures and concentrations of the conductive fillers. The real and imaginary parts of the complex permittivities of the composites were proportional to the filler concentrations. But, depending on the types of fillers and frequency band, the increasing rates of the real and imaginary parts with respect to the filler concentrations were all different. These different rates can have an effect on the thickness in designing the single layer microwave absorbers. The effect of the different rates at 10 GHz was examined by using Cole-Cole plot; the plot is composed of a single layer absorber solution line and measured permittivities from these three types of composites. Single layer absorbers of 3 different thicknesses using carbon nano materials were fabricated and the -10 dB band of absorbing performances were all about 3 GHz.

• Korean Journal of Biological Psychiatry
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• v.18 no.3
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• pp.163-167
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• 2011

Complex regional pain syndrome (CRPS) is a disease that causes chronic spontaneous pain and hyperesthesia of one or more parts of legs and arms, which is accompanied with problems of the automatic nervous system or the motor nervous system. However, up to date, it is unclear what causes the syndrome and how to diagnose and treat it. Although several treatments including medication and sympathetic nerve block are performed against CRPS, the therapeutic effect of the treatments is limited. The electroconvulsive thera-py (ECT), of which the mechanism is not clarified, is a treatment used for treatment-resistant depression. ECT is also reported to be effective against pain. Therefore, we performed the ECT for a 24-year-old female patient who has been diagnosed as CRPS. Her pain had not been much improved by medications and interventional procedures. At admission to a psychiatric ward for ECT, she com-plained of over 8 points of pain on visual analogue scale and the constrained movement around the painful part. Eight ECTs-three times a week-were performed for three weeks in hospital and then the ECT once a week was performed after her leaving the hospital. During the ECTs, pain had been reduced and the range of movement in the constrained parts had increased. Further systematic re-search is needed to confirm the effect of electroconvulsive therapy against CRPS.

• The Korean Journal of Applied Statistics
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• v.24 no.3
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• pp.465-475
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• 2011

In this paper, we have considered the problems of the estimation of the gross areas of a factory site relating to the areas of industrial complex lands based on a statistical forecasting model and the results of a sampling survey. In respect to the data of a gross areas of a factory site, we have only the sizes from 1981-2003. In 2009, the Korea Industrial Complex Corp. conducted a sampling survey to estimate its bulk size, and investigate the demands of its sizes for the next five years. In this study, we have adopted the sampling survey results, and have created a statistical growth model for the gross areas of a factory site to improve the prediction for the areas of a factory site. The three-different parts of data: the results of areas of a factory site by Korea National Statistical Office, imputation results by the statistical forecasting model, and sampling survey results have used as the basis for analysis. The combination of the three-different parts of data has created a new forecasting value of the areas of a factory site through the spline smoothing method.

• The Journal of Information Systems
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• v.8 no.2
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• pp.145-168
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• 1999

There are still occurring aviation accidents in spite of great preventing efforts all over the world. This paper contains some methods to prevent aircrafts deficiencies and accidents. First part of this paper refers to the background of those aviation deficiencies on mechanical, human and environment structures which influence directly to the air accidents and general survey on various theories of the aircraft's systems. On the way we discussed the general situations of the air tool's deficiencies which cause tragic accidents to the human lives and assets. After analysis on the situations we suggest the new systems which would forecast more detail accuracies concerned air elements for the safety flying. Then we introduce the following new systems resulting from the forecasting which can solve problems on aircraft deficiencies and complex interrelationships among air accidental factors. To simplify the complex systems, we needed to build the mechanical and organizational database for maintaining the procedures of the past troubleshooting on the major parts preventing deficiencies of those mechanical units. These suggested systems will contribute a great deal of aids, the maintenance credibility and air safety for the air operations and all customers in the world. Avoiding the past troubleshooting from just by using simple systems which can forecast main causes of the units and parts of the crafts, this system will be able to provide excellent management tools for the promoting aviational industries. The comfortable and convenient air operations are very valuable works, and the scientific method and detail maintenance will improve our daily air life by minimizing accidents. Adapting these developing systems, for the forecasting aircraft deficiencies and accidents can be integrated with the other aircraft management systems to promote more air safety in the world. This study is focused to eliminating aircraft accidents through forecasting deficiency symptom procedures by relational coordinations among all of the systems. Futhermore we need continuously detailed analysis and study for eliminating air accidents all together those who work in those fields.

• Journal of Mechanical Science and Technology
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• v.20 no.10
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• pp.1765-1772
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• 2006

High-pressure die casting such as thixocasting and rheocasting is an effective process in the manufacturing automotive parts. Following the recent trend in the automotive manufacturing technologies, the product design subject to the die casting becomes more and more complex. Simultaneously the injection speed is also designed to be very high to establish a short cycletime. Thus, the requirement of the die design becomes more demanding than ever before. In some cases the product's shape can have multiple slender manifolds. In such cases, design of the inlet and outlet parts of the die is very important in the whole manufacturing process. The main issues required for the qualified products are to attain gentle and uniform flow of the molten liquid within the passages of the die. To satisfy such issues, the inlet cylinder ('bed cylinder' in this paper) must be as large as possible and simultaneously the outlet opening at the end of each passage must be as small as possible. However these in turn obviously bring additional manufacturing costs caused by re-melting of the bed cylinder and increased power due to the small outlet-openings. The purpose of this paper is to develop effective simulation methods of calculation for fluid flows in multiple columns, which mimic the actual complex design, and to get some useful information which can give some contributions to the die-casting industry. We have used a commercial code CFX in the numerical simulation. The primary parameter involved is the size of the bed cylinder. We will show how the very small opening of the outlet can be treated with the aid of the porous model provided in the code. To check the validity of the numerical results we have also conducted a simple experiment by using water.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.1
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• pp.60-70
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• 2021

Recently, with the development of technologies for the fourth industrial revolution, convergence and complex technology are being applied to aircraft, electronic home appliances and mobile devices, and the number of parts used is increasing. Increasing the number of parts and the application of convergence technologies such as HW (hardware) and SW (software) are increasing the No Defect Found (NDF) phenomenon in which the defect is not reproduced or the cause of the defect cannot be identified in the subsequent investigation systems after the discovery of the defect in the product. The NDF phenomenon is a major problem when dealing with complex technical systems, and its consequences may be manifested in decreased safety and dependability and increased life cycle costs. Until now, NDF-related prior studies have been mainly focused on the NDF cost estimation, the cause and impact analysis of NDF in qualitative terms. And there have been no specific methodologies or examples of a working-level perspective to reduce NDF. The purpose of this study is to present a practical methodology for reducing NDF phenomena through data mining methods using quantitative data accumulated in the enterprise. In this study, we performed a cluster analysis using market defects and design-related variables of mobile devices. And then, by analyzing the characteristics of groups with high NDF ratios, we presented improvement directions in terms of design and after service policies. This is significant in solving NDF problems from a practical perspective in the company.

• Journal of Multimedia Information System
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• v.7 no.1
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• pp.1-10
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• 2020

The image analysis is an important and predominant task for classifying the different parts of the image. The analysis of complex image analysis like histopathological define a crucial factor in oncology due to its ability to help pathologists for interpretation of images and therefore various feature extraction techniques have been evolved from time to time for such analysis. Although deep reinforcement learning is a new and emerging technique but very less effort has been made to compare the deep learning and deep reinforcement learning for image analysis. The paper highlights how both techniques differ in feature extraction from complex images and discusses the potential pros and cons. The use of Convolution Neural Network (CNN) in image segmentation, detection and diagnosis of tumour, feature extraction is important but there are several challenges that need to be overcome before Deep Learning can be applied to digital pathology. The one being is the availability of sufficient training examples for medical image datasets, feature extraction from whole area of the image, ground truth localized annotations, adversarial effects of input representations and extremely large size of the digital pathological slides (in gigabytes).Even though formulating Histopathological Image Analysis (HIA) as Multi Instance Learning (MIL) problem is a remarkable step where histopathological image is divided into high resolution patches to make predictions for the patch and then combining them for overall slide predictions but it suffers from loss of contextual and spatial information. In such cases the deep reinforcement learning techniques can be used to learn feature from the limited data without losing contextual and spatial information.

• Journal of Fashion Business
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• v.12 no.2
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• pp.134-152
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• 2008

Functional, aesthetic and symbolic working uniforms in the industrial complex are demanded by employees and employers. The purpose of this research was to find out the actual wearing condition and preference of the working uniform design in the industrial complex. The research selected 7 enterprise subjects located in the Changwon National Industrial Complex and adopted a questionnaire method. 912 workers categorized into 4 work groups according to their work posts replied in total. The data and the degrees of satisfaction/preference of the working uniforms were analysed into descriptive statistics and F-tests by using the SPSS S/W package. The results were as follows: First, the style of the working uniform was the standard two-piece style. Second, the degree of the satisfaction with the entrepreneurial image implied to the working uniform was 2.83 throughout the 5-scale evaluation. In addition, the degree of the satisfaction with the working uniform colors was in between 2.94 and 2.96. Third, unsatisfied parts of the upper and lower uniform garments were: sleeve > pocket > collar; and waist belt loop > hip pocket > hem line respectively. Fourth, beige was the most preferred color for the working uniform top and bottom both. The most preferred color images were the calm and safety and the bright and light in order. Especially, the demand on the safety factors and soil proof colors of the outside field workers was much higher than the clerical workers. Fifth, the blouson type jacket with shirts collar or soutien roll collar was more preferred to than the casual style; and the straight formal pants were more preferred to than the casual/sweat sports pants styles. Sixth, inner pockets to keep the mobile phone and pens were required for upper garment details specially by manufacture workers. Increase of the waist belt loop numbers was required by all work groups.

• Journal of the Optical Society of Korea
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• v.17 no.1
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• pp.27-32
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• 2013

Based on the dispersive feature of the dielectric function of noble metals and the wave vector conservation in physics, both the plasma effect and the complex refractive index, which are profoundly correlated to the complex dielectric function and permeability, have been studied and analyzed. The condition to induce a bulk or a surface plasma in the visible region will not be satisfied, and there will be one solution for the real and the imaginary parts of the refractive index, restricting it only to region I of the complex plane. The results given in this work will aid in understanding the properties of light transmission at the metal/dielectric interface as characterized by the law of refraction in nature.

• Journal of Oriental Neuropsychiatry
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• v.34 no.2
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• pp.61-69
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• 2023

Objectives: To examine the effect of complex Korean medical treatment on tic disorder in children who visited the neuropsychiatric clinic of Korean medicine. Methods: Medical records of 35 patients diagnosed with tic disorder based on DSM-V who received complex Korean medical treatment (herbal medicine, acupuncture and Korean psychotherapy) were reviewed. Tic disorder was then evaluated by Yale Global Tic Severity Scale (YGTSS) before and at 4, 8, and 12 weeks after treatment to determine whether their symptoms were improved. Results: 1) After the treatment, mean YGTSS was reduced from 35.54±14.77 to 23.20±12.65. There were statistically significant changes between scores according to the time of treatment (p< 0.05). 2) At the time of visit, symptoms of motor tics were in the order of eyes, neck and shoulders, mouth, head and arms & hands, nose, face, upper body and other parts, and legs and symptoms of vocal tics were in the order of sniffing, dry coughing and MMM, AA and whistling, and other sounds. 3) For 35 patients, herbal medicine was prescribed every two weeks. The frequency of prescriptions used was in the order of Shihogayonggolmoryo-tang, Gami-ondam-tang, and others. 4) The frequency of herbs used in 35 patients was in the order of Poria, Zingiberis Rhizoma Recens, Pinelliae Rhizoma and Scutellariae Radix, Bupleuri Radix, Ostreae Concha and Bovis Ossis Fossilia, and others. Conclusions: Complex Korean medical treatment including herbal medicine, acupuncture, and Korean psychotherapy is effective for reducing tic symptoms in children.