• Korean Journal of Computational Design and Engineering
• /
• v.12 no.6
• /
• pp.422-428
• /
• 2007

Presented in the paper is a procedure to reconstruct a triangular mesh from a point cloud. Although, the proposed procedure is based on the well-known Voronoi diagram approach, it introduces a selection method of 'Pole' to improve the quality of resulting mesh. To select the appropriate Poles for high quality of Triangular mesh, the patterns that the Poles affect to the mesh quality are carefully analyzed. It is possible to improve the mesh quality by controlling the selection method of 'Pole' in terms of distance limit. The initial mesh obtained by the proposed procedure may include invalid triangles. To relieve this problem, a slicing method is proposed to remove invalid triangles from the initial mesh. At last, correcting technique of normal vectors of generated mesh is introduced.

• Educational Technology International
• /
• v.10 no.2
• /
• pp.107-125
• /
• 2009

This study seeks to prove three points through the research. The first point is to examine the changes of international attitudes with actual experiences using synchronous international distance learning. The second point is to examine the effectiveness of a synchronous international distance system. And the final point is to compare international attitudes among middle school and undergraduate school students in Korea and Japan. The study used the DVTS for audio and video communication tools and automatic translating chat as a text communication tool. This combination of communication tools was very effective for students from both countries to communicate for international collaborative learning activities. The study found several interesting patterns of attitude change from the results of the study. For whole category analysis, there are positive changes in four categories of international attitudes: consciousness to foreign countries, consideration for other's viewpoints, motivation for international education, and recognition for the counterpart country. However, there was no change in the nationality category.

• Journal of Intelligence and Information Systems
• /
• v.25 no.1
• /
• pp.63-83
• /
• 2019

Investors prefer to look for trading points based on the graph shown in the chart rather than complex analysis, such as corporate intrinsic value analysis and technical auxiliary index analysis. However, the pattern analysis technique is difficult and computerized less than the needs of users. In recent years, there have been many cases of studying stock price patterns using various machine learning techniques including neural networks in the field of artificial intelligence(AI). In particular, the development of IT technology has made it easier to analyze a huge number of chart data to find patterns that can predict stock prices. Although short-term forecasting power of prices has increased in terms of performance so far, long-term forecasting power is limited and is used in short-term trading rather than long-term investment. Other studies have focused on mechanically and accurately identifying patterns that were not recognized by past technology, but it can be vulnerable in practical areas because it is a separate matter whether the patterns found are suitable for trading. When they find a meaningful pattern, they find a point that matches the pattern. They then measure their performance after n days, assuming that they have bought at that point in time. Since this approach is to calculate virtual revenues, there can be many disparities with reality. The existing research method tries to find a pattern with stock price prediction power, but this study proposes to define the patterns first and to trade when the pattern with high success probability appears. The M & W wave pattern published by Merrill(1980) is simple because we can distinguish it by five turning points. Despite the report that some patterns have price predictability, there were no performance reports used in the actual market. The simplicity of a pattern consisting of five turning points has the advantage of reducing the cost of increasing pattern recognition accuracy. In this study, 16 patterns of up conversion and 16 patterns of down conversion are reclassified into ten groups so that they can be easily implemented by the system. Only one pattern with high success rate per group is selected for trading. Patterns that had a high probability of success in the past are likely to succeed in the future. So we trade when such a pattern occurs. It is a real situation because it is measured assuming that both the buy and sell have been executed. We tested three ways to calculate the turning point. The first method, the minimum change rate zig-zag method, removes price movements below a certain percentage and calculates the vertex. In the second method, high-low line zig-zag, the high price that meets the n-day high price line is calculated at the peak price, and the low price that meets the n-day low price line is calculated at the valley price. In the third method, the swing wave method, the high price in the center higher than n high prices on the left and right is calculated as the peak price. If the central low price is lower than the n low price on the left and right, it is calculated as valley price. The swing wave method was superior to the other methods in the test results. It is interpreted that the transaction after checking the completion of the pattern is more effective than the transaction in the unfinished state of the pattern. Genetic algorithms(GA) were the most suitable solution, although it was virtually impossible to find patterns with high success rates because the number of cases was too large in this simulation. We also performed the simulation using the Walk-forward Analysis(WFA) method, which tests the test section and the application section separately. So we were able to respond appropriately to market changes. In this study, we optimize the stock portfolio because there is a risk of over-optimized if we implement the variable optimality for each individual stock. Therefore, we selected the number of constituent stocks as 20 to increase the effect of diversified investment while avoiding optimization. We tested the KOSPI market by dividing it into six categories. In the results, the portfolio of small cap stock was the most successful and the high vol stock portfolio was the second best. This shows that patterns need to have some price volatility in order for patterns to be shaped, but volatility is not the best.

• 제어로봇시스템학회:학술대회논문집
• /
• 1993.10b
• /
• pp.212-217
• /
• 1993

In this paper, characteristics of the motions of a human arm are investigated experimentally. When the conditions of the target point are restricted, human adjusts its trajectory and velocity pattern of the arm to fit the conditions skillfully. The purpose of this work is to examine the characteristics of the trajectory, velocity pattern, and the size of the duration in the following cases. First, we examine the case of point-to-point motion. The results are consistent with the minimum jerk theory. However, individual differences in the length of the duration can be observed in the experiment. Second, we examine the case which requires accuracy of positioning at the target point. It is found that the velocity pattern differs from the bell shaped pattern explained by the minimum jerk theory, and has its peak in the first half of the duration. When higher accuracy of the positioning is required, learning effects can be observed. Finally, to examine the case which requires constraint of the arm posture at the target point, we conduct experiments of a human trying to grasp a cup. It is considered that this motion consists of two steps : one is the positioning motion of the person in order to start the grasping motion, the other is the grasping motion of the human's hand approaching toward the cup and grasping it. In addition, two representative velocity patterns are observed : one is the similar velocity pattern explained in the above experiment, the other is the velocity pattern which has its relative maximum in the latter half of the duration.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.49 no.6
• /
• pp.322-329
• /
• 2000

BIST(Built-in Self Test) has been considered as the most promising DFT(design-for-test) scheme for the present and future test strategy. The most serious problem in applying BIST(Built-in Self Test) into a large circuit is the excessive increase in test time. This paper is focused on this problem. We proposed a new BIST construction scheme which uses a parallel divide-and-conquer method. The circuit division is performed with respect to some internal nodes called test points. The test points are selected by considering the nodal connectivity of the circuit rather than the testability of each node. The test patterns are generated by only one linear feedback shift register(LFSR) and they are shared by all the divided circuits. Thus, the test for each divided circuit is performed in parallel. Test responses are collected from the test point as well as the primary outputs. Even though the divide-and-conquer scheme is used and test patterns are generated in one LFSR, the proposed scheme does not lose its pseudo-exhaustive property. We proposed a selection procedure to find the test points and it was implemented with C/C++ language. Several example circuits were applied to this procedure and the results showed that test time was reduced upto 1/2151 but the increase in the hardware overhead or the delay increase was not much high. Because the proposed scheme showed a tendency that the increasing rates in hardware overhead and delay overhead were less than that in test time reduction as the size of circuit increases, it is expected to be used efficiently for large circuits as VLSI and ULSI.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.30 no.2 s.150
• /
• pp.207-220
• /
• 2006

The purpose of the study is to develop the basic pattern of casual jacket for men aged between 25 and 34. Compared to the tailored jackets, casual jackets are designed much more diverse form depending on the target customer, price range and moreover fashion trend. Therefore in order to reduce the cost and time of developing new style, pattern draft from the basic pattern is better approach rather than develop each style form the measurements every time. For men's casual jacket pattern draft, the basic pattern of fit and comfort was developed through following research procedures. 173 men were surveyed about their habit of buying and wearing of casual jackets. MDs and pattern designers of 10 casual wear brands for men were interviewed. As a starting point, 3 different basic patterns were selected. 2 patterns were from the 2 interviewed brands and the last one was the pattern of ESMOD. The 3 patterns were studied by means of comparing measurements and general styling. As a results it was found that the pattern of S brand is featuring I silhouette, the pattern of K brand is featuring H silhouette and the pattern of ESMOD is featuring Y silhouette. The results of wearing test showed that the pattern of S brand is the best among the three. They were to add ease around the chest line and waist line, to relocate the waist line and the break point, to increase the jacket length and upper arm width. The improved pattern was made of polyester for the wearing test. The wearing test showed developed pattern was improved significantly. To verify the use of developed basic pattern, two buttoned single jacket was made.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.17 no.4
• /
• pp.1-14
• /
• 2015

This study mainly analyzes that designing patterns of an adult women Jeogori that takes advantage of patterns from each textbooks and complements the disadvantages based on the analysis of data from the dress evaluation and comparison of materials. The modification of a size specification is needed for the standard body as an adjust of the length of Jogori between front and back, mediation for bust width between front and back, a movement for the based line of Sup and Godae. As a result, the suitable pattern according to the standard somatotype is as below. Jeogori Length of front is determined by the length of back which was measured from side neck point to bust point plus three centimeters, and give three and half centimeters more in front. This three and half centimeters is for the curved in front of your body due to the chest. Bust width of front and back have to show the differences of human body. Bust width of front is calculated as bust girth into quarters and add two centimeters. Bust width of back gives one centimeter behind the curve from the center line in order to reduce the floating phenomenon. So, the amount of center back line dart is one centimeter. Arm hole girth measures as dividing bust girth into four. Also, Goedae width has two methods to measure. First, divide bust girth into ten equal parts and subtract 0.5 centimeters from it. Second, measure neck girth and divide it by four. Sleeve length is equal to Hwajang minus bust width of front. Hand wrist calculates in using bust girth. Make bust girth into quarters and multiply three fifths. Side line measures as deducting from Jeogori length of back to Arm hole girth and multiply two thirds.

• Korean Institute of Interior Design Journal
• /
• v.26 no.5
• /
• pp.106-116
• /
• 2017

In the 1900s, the cultural crossing of East and West was realized through the acceptance and reproduction of culture. Cultural change in the Orient was the result of attempts to harmonize the West's images, which they chose in their respective countries, with their own culture. However, research on design history until now has been centered on the West, and East was regarded as a beneficiary of civilization inherited from Western's. From the point of view of Western design history as a main trend, the unique characteristics of Korean design culture are not revealed. Therefore, through this studies, we want to distinguish Korea's modern design, which has been recognized as a minority. For the study, through the wallpaper, which is one of the detailed components of the interior space in modern times, we try to analyze the socio - cultural historical factors and design characteristics influencing the formation of the interior space in modern times. Summarizing a result of research. The early modern wallpaper of England mainly uses plants as motifs. But In Korea, animal patterns and letter patterns were used. The reason why European wallpaper was mainly a plant at the time was that the structure of the motif was useful for the process of creation. However, in the case of the Korean wallpaper pattern, the theme was selected according to the meaning of the motif, and it was abstracted appropriately for the 2D design. As a result, many geometric shapes were formed. In addition, European wallpaper pattern is more complex and organic than Korean wallpaper pattern. Therefore, the boundary of the central pattern as the basic unit is unclear and the patterns are connected. The pattern development method is not a simple repetition but a combination of symmetry and repetition. In Korea, on the other hand, the boundaries of unit patterns are clear and patterns are developed by simple repetition. There are many diamond-type repeating patterns in particular.

• Journal of the Korea Fashion and Costume Design Association
• /
• v.16 no.1
• /
• pp.53-64
• /
• 2014

The main objective of this research was to understand the characteristics of printed geometric patterns through the statistical & qualitative analysis of fashion appeared in contemporary female collections 2011 S/S to 2013 A/W. Data collection of 294 was done through review of 'pr$\hat{e}$t-$\grave{a}$-porter Collections' of three major fashion cities; Paris, Milan and NY. Statistical analysis of frequency was conducted. Also qualitative interpretation of natural print design' characteristics were completed. The main findings were as followed; 1,636 of the total 15,852 designs were printed patterns in 12 Collections and the occurrence rate of printed geometric patterns in three collections were 8.6% in Milan, 9.2% in Paris and 12.9% in N.Y. Most geometric patterns were the types of compact or medium density in a front patterns with a variety of sizes and mainly applied to the one piece dress or two piece clothing item combination styles. Formative Characteristics of printed geometric patterns were classified into four types. First, a variety of thicknesses and shapes, such as a line or a rectangle shape to take advantage of the types of the typical geometric pattern. Second types were using the motifs which inspired by geometric shapes such as point, circle star and other special geometric shapes and arranging them regularly with various sizes and density. The third was repeated particular motifs which based on complex and sophisticated mathematical formulas. Fourth were the specific diagram types of bold and free shapes or dividing the flat and arranging them without rules, or the combination type of various geometric motifs.

• Journal of Korea Technology Innovation Society
• /
• v.20 no.4
• /
• pp.1243-1261
• /
• 2017

Mobile telecom markets have dramatically increased in the last decade due to a remarkable subscriber base growth. The diffusion patterns of the services are a major concern for mobile carriers preparing those new services. We assume that the diffusion patterns of those services will be similar to those of previous mobile services, and discovering the diffusion patterns of those services is an essential task of mobile carriers for preparing the next mobile services. This study attempts to classify some groups which show similar diffusion patterns of mobile services. Using a traditional diffusion model, this study estimates diffusion patterns of twenty five western European countries. The estimation is based on the monthly penetration ratio of those countries from 1993 to 2004. Based on the estimation, the cluster analysis discovers that there are two different countries groups in terms of mobile diffusion pattern: high imitation countries and low imitation countries. The critical point for classifying the two groups in terms of imitation effect was 0.90. The results provide the basis for developing a causal relationship model which explains the different diffusion pattern of mobile services and planning new networks for the advanced mobile services.