• 한국수학사학회지
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• 제32권4호
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• pp.159-173
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• 2019

In this paper, we examine the brief history of the ring of four almonds regarding Mesopotamian mathematics, and present reasons why the Omar Khayyam's triangle, a special right triangle in a ring of four almonds, was essential for artisans due to its unique pattern. We presume that the ring of four almonds originated from a point symmetry figure given two concentric squares used in the proto-Sumerian Jemdet Nasr period (approximately 3000 B.C.) and a square halfway between two given concentric squares used during the time of the Old Akkadian period (2340-2200 B.C.) and the Old Babylonian age (2000-1600 B.C.). Artisans tried to create a new intricate pattern as almonds and 6-pointed stars by subdividing right triangles in the pattern of the popular altered Old Akkadian square band at the time. Therefore, artisans needed the Omar Khayyam's triangle, whose hypotenuse equals the sum of the short side and the perpendicular to the hypotenuse. We presume that artisans asked mathematicians how to construct the Omar Khayyam's triangle at a meeting between artisans and mathematicians in Isfahan. The construction of Omar Khayyam's triangle requires solving an irreducible cubic polynomial. Omar Khayyam was the first to classify equations of integer polynomials of degree up to three and then proceeded to solve all types of cubic equations by means of intersections of conic sections. Omar Khayyam's triangle gave practical meaning to the type of cubic equation $x^3+bx=cx^2+a$. The work of Omar Khayyam was completed by Descartes in the 17th century.

• 동의생리병리학회지
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• 제28권1호
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• pp.76-81
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• 2014

The aim of this study was to build the diagnosis criteria of Qi deficiency using distribution of sum of 11 items for Qi deficiency in stroke patients. Between September 2006 and December 2010, 2,994 patients from 11 Korean medical hospitals were asked to complete the Korean Standard Pattern Identification for Stroke (K-SPI-Stroke) questionnaire as a part of project 'Fundamental study for the standardization and objectification of pattern identification in traditional Korean medicine for stroke (SOPI-Stroke). Each patient was independently diagnosed by two experts (traditional Korean medicine physicians) from the same site according to one of five patterns. 2,994 patients were divided modeling and testing in 70:30 ratio by stratification of pattern identification. We calculated the sensitivity, specificity, accuracy and odds ratio (OR) using distribution of sum of 11 items (signs and symptoms) for Qi deficiency. More than four from 11 items of Qi deficiency in modeling dataset, sensitivity, specificity, accuracy and OR was 70.07%, 74.94%, 73.92% and 7.00, respectively. In testing dataset, 78.31%, 73.45%, 74.47% and 9.98, respectively. Although this values are not high, after values of sensitivity, specificity, accuracy and OR should be more than current value, and then we should be able to suggest as objective diagnosing criteria.

• Fisheries and Aquatic Sciences
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• 제4권4호
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• pp.219-228
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• 2001

Surface sediments (0- 5 cm), mussels (Mytilus coruscus and M. edulis) and oysters (Crassostrea gigas) were sampled at 20 stations in Korean coast during a period of February to July 2000. Samples were analyzed for polycyclic aromatic hydrocarbons (PAHs) content using gas chromatography coupled to mass spectrometer detector (GC/MSD). The sediment $\sum PAH$ concentration varied from 7 to 1,214 ng/g dry weight and the level of carcinogenic PAHs of six species ranged from 1 to 563 ng/g dry weight in surface sediments. In organisms, the levels of $\sum PAH$ were in the range of 63-876 ng/g dry weight and the concentrations of carcinogenic PAHs of six species were in the range of 4-582 ng/g dry weight. The highest PAH concentrations in sediments and organisms were in samples from Station 5 in Pohang coast and Station 8 in Jinhae coast, respectively. $\sum PAH$ concentrations in sediments and organisms collected from Korean coast were slightly low or comparable to those in other countries. The contribution of ring aromatic groups to sum of 16 PAHs in sediments and organisms showed a similar pattern for most stations. In sediments, the predominant contributions were four and five ring aromatics like fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene and benzo[a]pyrene. In the organisms, four ring aromatics like fluoranthene, pyrene, benzo[a]anthracene and chrysene were predominant PAH species. Several molecular indices such as phenanthrene/anthracene, fluoranthene/pyrene and LMW/HMW ratio were used to identify the origin of PAH contamination in sediments. The results indicate that PAHs of Korean coast were mainly of pyro1ytic contaminants with slight petrogenic input. A high correlation within individual PAH compound in marine sediments was observed, while correlation in organisms showed a highly significant relationship for heavier molecular weight PAHs.

• 한국통신학회논문지
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• 제39A권2호
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• pp.92-99
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• 2014

본 논문은 결정 트리(Decision tree) 구조를 기반으로 한 표정 인식 방법을 제안한다. ASM(Active Shape Model)과 LBP(Local Binary Pattern)를 통해, 표정 영상들의 국소 특징들을 추출한다. 국소 특징들로부터 표정들을 잘 분류할 수 있는 판별 특징(Discriminant feature)들을 추출하고, 그 판별 특징들은 모든 조합의 각 두 가지 표정들을 분류시킨다. 분류를 통해 얻어진 정인식의 합을 통해, 정인식 최대화 기반 국소 영역과 표정 조합을 결정한다. 이 가지 분류들을 종합하여, 결정 트리를 생성한다. 이 결정 트리 기반 표정 인식률은 약 84.7%로, 결정 트리를 고려하지 않은 방법보다, 더 좋은 인식 성능을 보였다.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.601-605
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• 2009

We have proposed a measurement system for measuring a whole shape of an object easily. The proposed system consists of a camera and a cylinder whose inside is coated by a mirror layer. A target object is placed inside the cylinder and an image is captured by the camera from right above. The captured image includes sets of points that are observed from multiple viewpoints: one is observed directly, and others are observed via the mirror. Therefore, the whole shape of the object can be measured using stereo vision in a single shot. This paper shows that a prototype of the proposed system was implemented and an actual object was measured using the prototype. A method based on a pattern matching which uses a value of SSD (Sum of Squared Difference), and a method based on DP (Dynamic Programming) are employed to identify a set of corresponding points in warped captured images.

• Journal of Ecology and Environment
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• 제29권5호
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• pp.433-438
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• 2006

To elucidate the mechanisms by which algal food quality affect Daphnia growths, we measured carbon incorporation rates and respiration rates of Daphnia magna with Cryptomonad Rhodomonas minuta, green algae Scenedesmus acutus and cyanobacteria Synechococcus sp. with varying physiological states as food. Carbon assimilation rates were high with R. minuta and S. acutus and low with Synechococcus sp. showing a similar pattern to the growth rate pattern. There was no clear difference among respiration rates of three algal species. Carbon assimilation rates and respiration rates of D. magna appeared to be independent on Molar C:P ratios in algal foods. Carbon growth efficiencies (incorporated carbon per assimilated carbon amount) were lower when D. magna fed with Synechococcus sp. than fed with R. minuta or S. acutus. Analysis of variance results show that carbon assimilation rates which were sum of incorporation and respiration rates and carbon growth efficiencies were only dependant on species affiliation. Overall, our results showed that algal species with varying ${\omega}3$ polyunsaturated fatty acid content led different carbon incorporation rates and overall carbon assimilation rates of D. magna.

• 한국실내디자인학회논문집
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• 제17권4호
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• pp.84-91
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• 2008

The objective of this study is to investigate how visitors' behavior change in relation to the pattern of exhibition in art museum. For the purpose Busan Museum of Modern Art was selected as the sample in this study. And two patterns of exhibition, namely the planar exhibition and the three dimensional exhibition, were surveyed using the tracking movement method. The data gathered from random-sampling 60 visitors in a art museum was analyzed by the correlation analysis and T-test. The results are as follows; 1) There is no meaningful difference in visitors' behavior by the exhibition pattern in terms of their viewing area, viewing time, viewing distance, viewing velocity, viewing rate. 2) In contrast, there is meaningful difference in terms of the number of stops by visitors and the time spent without movement to see the objects; visitors stopped more often and stayed longer within the three dimensional exhibition space than the planar exhibition in a art museum. In sum, visitors extrinsically show no big behavioral difference between the planar exhibition and the three dimensional exhibition, but much difference in the way they communicate with objects; they show more active behavior within the three dimensional exhibition space.

• 한국조리학회지
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• 제11권4호
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• pp.118-133
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• 2005

In the management activities of head office in supporting franchisees in domestic food-service enterprises, the raw material supply plays a positive role to support franchisees' operation activity and it comes into conflict with them at the same time. In this paper, I have tried to find out the relationship between raw material supplying and the satisfaction of the franchisees by experimental research in order to research the route of head office's raw material supplying. To sum up the results, it was found out there is no meaningful relationship between the raw material supplying and the franchisees satisfaction (intention to renew the agreement), It indicates it would be more effective for the franchisees to buy the raw materials from the suppliers developed by the franchisees except some key materials in order to reduce the conflicts with the franchisees.

• 대한산업공학회지
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• 제41권3호
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• pp.267-274
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• 2015

In the semiconductor manufacturing post-FAB process, predicting a package test result accurately in the wafer testing phase is a key element to ensure the competitiveness of companies. The prediction of package test can reduce unnecessary inspection time and expense. However, an analysing method is not sufficient to analyze data collected at wafer testing phase. Therefore, many companies have been using a summary information such as a mean, weighted sum and variance, and the summarized data reduces a prediction accuracy. In the paper, we propose an analysis method for Wafer Map Image collected at wafer testing process and conduct an experiment using real data.

• 대한산업공학회지
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• 제27권4호
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• pp.424-431
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• 2001

This paper is concerned with the unconstrained two-dimensional cutting problem of cutting small rectangles (products), each of which has its own profit and size, from a large rectangle (material) to maximize the profit-sum of products. Since this problem is used as a sub-problem to generate a cutting pattern in the algorithms for the two-dimensional cutting stock problem, most of researches for the two-dimensional cutting stock problem have been concentrated on solving this sub-problem more efficiently. This paper improves Hifi and Zissimopoulos's recursive algorithm, which is known as the most efficient exact algorithm, by applying newly proposed upper bound and searching strategy. The experimental results show that the proposed algorithm has been improved significantly in the computational amount of time as compared with the Hifi and Zissimopulos's algorithm.