• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.1854-1868
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• 1995

An effective nesting algorithm has been proposed to allocate the arbitrary shapes on one or several raw sheets by applying the well-known simulated annealing algorithm as the optimization technique. In this approach, both the shapes to be allocated and the raw sheets are represented as the grid-based models. This algorithm can accommodate every possible situations encountered in cutting apparel parts from the raw leather sheets. In other words, the usage of the internal hole of a shape for other small shapes, handling of the irregular boundaries and the interior defects of the raw sheets, and the simultaneous allocation on more than one raw sheets have been tackled on successfully in this study. Several computational experiments are presented to verify the robustness of the proposed algorithm.

• Wind and Structures
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• v.19 no.1
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• pp.59-73
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• 2014

This paper presents the results of wind tunnel studies and numerical studies on a '+' plan shaped tall building. The experiment was carried out in an open circuit wind tunnel on a 1:300 scale rigid model. The mean wind pressure coefficients on all the surfaces were studied for wind incidence angle of $0^{\circ}$ and $45^{\circ}$. Certain faces were subjected to peculiar pressure distribution due to irregular formation of eddies caused by the separation of wind flow. Moreover, commercial CFD packages of ANSYS were used to demonstrate the flow pattern around the model and pressure distribution on various faces. k-${\varepsilon}$ and SST viscosity models were used for numerical study to simulate the wind flow. Although there are some differences on certain wall faces, the numerical result is having a good agreement with the experimental results for both wind incidence angle.

• The Journal of Korean Obstetrics and Gynecology
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• v.29 no.3
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• pp.47-56
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• 2016

Objectives: We evaluated the effect of Korean medical treatment in case of irregular menstruation (amenorrhea, oligomenorrhea) due to Polycystic ovarian syndrome (PCOS).Methods: 20 Amenorrhea or oligomenorrhea Patients with PCOS were treated with Korean medical treatment at least 3 months. We analyzed clinical data of 20 patients and checked effectiveness of treatment through the change of menstrual pattern.Results: After Korean medical treatment, Patients who complained menstrual irregularity due to PCOS were improved in menstrual condition. Among 14 amenorrhea patients, 12 patients (85.7%) started menstruation within 3 months. Among 6 Oligomenorrhea patients, 4 patients (66.7%) got better menstruation pattern than before.Conclusions: PCOS Patients who got Korean medical treatment showed better condition in menstruation pattern. Amenorrhea patients started menstruation without contraceptive pill and oligomenorrhea patients got better menstruation cycle.

• Journal of Information Technology Services
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• v.11 no.3
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• pp.89-101
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• 2012

The study investigated if IT investment in Korean financial markets for the past 18 years has grown following the s-curve pattern based on Nolan's growth model in order to find the correlation between IT investment and management performance in the financial industry. According to the research finding it can be said that the overall financial markets maintain s-curve pattern, and IT investment is related to management performance, particularly increase in total assets and net profit. However, each sector has defining features of growth patterns. The banking industry has grown similarly to the s-curve, and the insurance industry also shows the s-curve but it looks more like linear pattern. In terms of securities industry, its growth patterns can hardly be considered s-curve due to the irregular changes. his research outcome illustrates the analysis of IT growth patterns in the financial industry and thus, it is expected to be a useful reference when deciding the appropriate time for IT investment in the financial industry.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.447-452
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• 2000

The grinding plays a key role which decide the quality of a product finally. But the grinding process is very irregular, so it is very difficult to analyse the process accurately. Therefore it is very important in the aspect of precision and automation to reduce the idle time and to decide the proper dressing time by visualizing. In this study, we choose the direct method of observation by making use of computer vision, and apply pattern classification technique to the method of measuring the wheel surface. Pattern classification technique is proper to analyse complex surface image. We observe the change of the wheel surface by making use of the gray level run lengths which are representative prince in this technique.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.10
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• pp.916-923
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• 2011

The refrigerant after the expansion valve interchanges the heat at the evaporator. At this moment, the state of gas and liquid becomes two-phase flow and causes irregular noise. In order to avoid the noise, the two-phase flow pattern should be predicted. In this paper, the procedure to predict the two-phase flow patterns such as churn flow and annular flow was suggested using the CFD software. The experiments using refrigerant-supplying equipment was carried out and the noise levels according to the flow pattern were measured. The flow patterns predicted by this procedure showed good agreement with those by experiments. The churn flow is noisier than annular flow pattern.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.8
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• pp.1051-1057
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• 2013

In this study, an automatic surface-strain measurement system called "ASIAS-bio" has been developed. This system can be used even in cases in which it is very difficult to apply a regular grid pattern necessary for measuring surface-strain, such as curved or uneven surfaces; surfaces damaged by corrosion or contamination; or soft materials such as rubber, foam, and biological tissues. This system works independently of the measurement conditions including the material and its surface condition, grid pattern and size, grid marking method, and degree of deformation. A comparison between the strain distributions of the sheet metal parts measured by using this system and those obtained by a commercial system showed that this system was sufficiently reliable. In addition, the deformation of the swine joint capsule and human knee skin was measured by using this system to demonstrate its usefulness.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.4
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• pp.391-406
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• 2014

The performance of General-Purpose computation on Graphics Processing Units (GPGPU) is heavily dependent on the memory access behavior. This sensitivity is due to a combination of the underlying Massively Parallel Processing (MPP) execution model present on GPUs and the lack of architectural support to handle irregular memory access patterns. Application performance can be significantly improved by applying memory-access-pattern-aware optimizations that can exploit knowledge of the characteristics of each access pattern. In this paper, we present an algorithmic methodology to semi-automatically find the best mapping of memory accesses present in serial loop nest to underlying data-parallel architectures based on a comprehensive static memory access pattern analysis. To that end we present a simple, yet powerful, mathematical model that captures all memory access pattern information present in serial data-parallel loop nests. We then show how this model is used in practice to select the most appropriate memory space for data and to search for an appropriate thread mapping and work group size from a large design space. To evaluate the effectiveness of our methodology, we report on execution speedup using selected benchmark kernels that cover a wide range of memory access patterns commonly found in GPGPU workloads. Our experimental results are reported using the industry standard heterogeneous programming language, OpenCL, targeting the NVIDIA GT200 architecture.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.83-84
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• 2006

In this paper, we examine discharge characteristics of cross-linked polyethylene (since then; XLPE) according to thickness. Voltage was applied to power frequency by step method, and calibration of discharge was set to 50[pC] (slope=8.333). After the voltage was applied, for 10 [sec] (600 [cycle]), occurring discharge and number were detected. Determine of input pattern is difficult because discharge pattern is irregular. Therefore we investigated pattern using the K-means Analysis and Weibull function. Also we investigated variation of centroid and cluster.

• Journal of Fashion Business
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• v.22 no.5
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• pp.41-51
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• 2018

Cable knitting, one of the most representative structures of knitwear has been applied to a number of knit items in a variety of expressions every season. The purpose of this study is to analyze the various types of expressions applied with cable knitting techniques to make the necessary data for planning cable knit designs. The types of cable knitting were devide into two categories which are based on the cable knitting pattern and structure. Based on the pattern, firstly, formal type is a reproduction of traditional Aran knit style and is usually applied to a practical and comfortable timeless knit product. Secondly, informal type is irregular applied to patterns and directions to highlight the dynamics of cable patterns. Thirdly, contrasting type emphasizes the cable pattern by contrasting the color of the part of the cable pattern. Fourthly, figurative type is the expression of the conceptual motifs and using the cable knit pattern itself as motif. Based on the structure, firstly, open type is to emphasize patterns and spaces by utilizing open spaces created by the intersection of cabling stitches. Secondly, decorative type is to enhance the ornamental effect of cable knitting by various methods and other subsidiary materials. Thirdly, avant-garde type is applied in various ways with exaggerated volumes or textures using the three-dimensional effects of cable knitting. Through this study, we look forward to the possibility of expressing the unique aesthetic characteristics of each of the various knitting techniques.