• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.5
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• pp.1-6
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• 2022

This paper deals with the maximum cardinality matching(MCM) problem. The augmenting path technique is well known in MCM. MCM is obtained by $O({\sqrt{n}}m)$ time complexity augmenting path algorithm for the general graph, and O(m log n) algorithm for the bipartite graph. On the other hand, this paper suggests O(n) linear time algorithm. The proposed algorithm based on the basic principle of as possible as largest selected inter-vertex edges in order to obtain the MCM. This paper simply selects edge {u,𝜐} that the minimum degree vertex u and minimum degree vertex 𝜐 in N_G(u) 𝜈(G)=k times iteration. For various general and bipartite graphs experimental data, this algorithm can be get the 𝜈(G) exactly.

• Korean Journal of Culture and Social Issue
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• v.21 no.3
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• pp.339-353
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• 2015

The aim of this study is to explore the relationships among paranoid tendencies, cognitive characteristics and prejudice. Revised Minnesota Multiphasic Personality Inventory Pa scale, Harris-Lingoes Naivetes(Pa3), dichotomous thinking(DT), attributional style, prejudice toward minority groups(migrant workers, homosexuals, and homeless people) were administered to 557 college students. High Pa3 group was significantly low in prejudice toward minority groups. Also, the group with higher DT showed more prejudice toward minorities. The suggestions and the limitations of this study, and the directions of future study were discussed.

• Journal of the Korean Orthopaedic Association
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• v.54 no.5
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• pp.452-456
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• 2019

Carpal tunnel syndrome is rare in children. When it does occur in children, the most common causes reported are mucopolysaccharidosis and mucolipidosis. The median artery is a transitory vessel that develops from the axillary artery in early embryonic life and does not normally survive until postfetal life. In a small percentage of individuals, however, it persists into adulthood and is frequently accompanied by a bifid median nerve. A persistent median artery can be a cause of carpal tunnel syndrome in adults, but it is extremely rare in children and adolescents. This paper reports a case of a carpal tunnel syndrome caused by a persistent median artery and bifid median nerve in a 13-year-old girl.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.20-24
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• 2009

This study was conducted to investigate the roles of co-existed organic materials (OM) with different biodegradability in composting of cattle manure in terms of $CO_2$ emission and $NH_3$ volatilization. Either sawdust (SD, low biodegradability) or rice bran (RB, high biodegradability) was mixed with cattle manure at a various rate and the amounts of $CO_2$ emission and $NH_3$ volatilization were determined periodically during 4 weeks of composting. Percentage of dry matter loss during the composting period was also calculated. The amount of $CO_2$ emitted increased with increasing rate of OM and was significantly (P<0.01) higher in the RB treatment than in the SD treatment by 43 to 122% depending on the rate of OM Accordingly, % of dry matter loss during 4 weeks of composting was higher in the RB (rang: from 35.1 % to 41.5%) than that in the SD treatments (from 18.7% to 22.6%), showing that RB is more biodegradable than SD. During the early composting period up to 8 days, negligible amount of ammonia volatilization was detected in both treatments regardless of application rates. In the RB treatment, substantial amount of ammonia volatilization was detected thereafter, however, no meaningful ammonia volatilization was observed in the SD treatment until the end of composting. Such differences could be attributed to the different properties of SD and RB. For example, the high C/N ratio of SD could enhance $NH_4^+$ immobilization and thus decrease $NH_4^+$ concentration that is susceptible to ammonia volatilization. Binding of $NH_4^+$ on to phenolic compounds of SD may also contribute to the decrease in $NH_4^+$ concentration. Meanwhile, as RB has a relatively low C/N ratio, remineralization of immobilized $NH_4^+$ could increase $NH_4^+$ concentration as high as the level for the occurrence of ammonia volatilization. Therefore, our study suggests that OM which is resistant to biodegradation can reduce $NH_3$ volatilization largely by physico-chemical pathways across the entire composting period and that easily biodegradable OM can retard $NH_3$ volatilzation via microbial immobilization in the early period of composting followed by rapid remineralization, leading to substantial volatilization of $NH_3$ in the middle stage of composting.

• Journal of Chest Surgery
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• v.42 no.5
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• pp.597-603
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• 2009

Background: Atrioventricular valve regurgitation in pediatric patients with a functional single ventricles (FSV) - has been known as one of the important risk factors for death and unfavorable long-term results after a Fontan operation. We evaluated early and mid-term results of bivalvation valvuloplasty in FSV patients. Material and Method: We retrospectively evaluated 11 patients with a functional single ventricle who underwent bivalvationvalvuloplasty between 1999 and 2007. The degree of common atrioventricular valve regurgitation (CAVVR) was determined by color Doppler echocardiography (regurgitation grade scoring, trivial; 1, mild; 2, moderate; 3, severe; 4). Mean age at valve surgery was $6.9{\pm}7.0$ months (median 4 months, 24 days$\sim$21 months)and mean body weight was $6.2{\pm}2.8\;kg$ ($3.1{\sim}11.3\;kg$). Nine patients had isomerism heart and two of them had TAPVC. The concomitant procedures were performed in all but one patient. Additional commissural closure was performed in 3 patients and commissural annuloplasty in another 3 patients. Result: There was one hospital death after. surgery. A 32-day old patient who had been preoperatively dependent on a ventilator died of air way and lung problems 4.3 months after pulmonary artery banding and bivalvation valvuloplasty. Mean follow-up duration was 40 months ($4.3{\sim}114$ months). Mean preoperative CAVVR score was $3.3{\pm}0.6$, which decreased to $1.9{\pm}0.7$ postoperatively (p<0.0001). This residual regurgitation slightly increased to $2.2{\pm}0.4$ (no statistical significance) after a mean follow-up of 1.4.3 months. Six patients (60%) required re-operations for residual regurgitation at a subsequent bidirectionalcavopulmonary shunt or Fontan operation. One patient with Ebsteinoid malformation of the right sided atrioventricular valve required valve replacement due to stenoinsufficiency. Another patient required edge-to-edge repair at the right sided AV valve (between the right mural leaflet and the bridging leaflets). The remaining 4 patients required additional suture placements between bridging leaflets with or without commissural annuloplasty. All survivor had trivial or mild CAVVR at the latest follow-up. Conclusion: Bivalvation valvuloplasty for CAVVR in FSV patients is. an effective and safe procedure. However, significant numbers of the patients have small residual regurgitation and require additional valve procedures at subsequent operations. Long-term observations to monitor progression of the CAVVR is mandatory.

• Journal of Educational Research in Mathematics
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• v.27 no.3
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• pp.537-555
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• 2017

This paper compared and contrasted Korean and Singaporean textbooks in order to explore the direction and possibility of teaching the big ideas related to the addition and subtraction of fractions with different denominators proposed by Lee & Pang (2016a). Firstly, we examined the teaching sequences related to the addition of fractions with different denominators in a series of elementary mathematics textbooks of Korea and Singapore. We then analyzed what types of representations are used and how the representations are presented for the big ideas related to the addition of fractions with different denominators. The results of the analysis showed that the contents related to fraction addition are addressed more gradually and systematically in Singaporean textbooks compared to Korean counterparts. The graphical representations appeared in the Singaporean textbooks provide specific implications for teaching the big ideas of the addition of fractions with different denominators. Based on such implications, we expect that the big ideas related to the addition of fractions with different denominators will be addressed explicitly and systematically in Korean textbooks.

• Korean Journal of Plant Resources
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• v.12 no.3
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• pp.171-178
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• 1999

The purpose of this study was to investigate the optimal mixture ratio for the mycelial culture of the Pleurotus ostreatus. The chief cultural media in this study were cotton hull, sawdust and rice straw and the supplemental media were zeolite, corn cob, defatted rice bran, white cotton, tobacco trash powder, rice hull and peat. The results of this study were as follows; the optimal mixture ratio of the chief cultural media were effective in 6 : 3 : 1(V/V, %), and the mycelial growth and density in the supplemental media were considerably better 1% zeolite,3% corn cob, 5% defatted rice bran, 1% white cotton, 1% tobacco trash powder, 7% rice hull in good order. The optimal mixture ratio be to the mixed supplemental media in the chief cultural media were as follows ; 2 : 2(V/V, %) at the conditions of mixed zeolite and corn cob; 3 : 2(V/V, %) at the conditions of mixed defatted rice bran and white cotton; 1 : 3(V/V, %) at the conditions of mixed tobacco trash powder and rice hull. At the conditions of the whole cultural media mixed, the mycelial growth and density were in good conditions ; cotton hull, sawdust, rice straw, zeolite, corn cob, defatted rice bran, white cotton, tobacco trash powder, rice hull, and peat were mixed 43.0 : 17.2 : 25.8 : 2.0 : 2.0 : 3.0 : 2.0 : 1.0 : 3.0 : 1.0 (V/V, %).

• The Korean Journal of Applied Statistics
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• v.32 no.3
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• pp.349-374
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• 2019

A class imbalance problem arises when one class outnumbers the other class by a large proportion in binary data. Studies such as transforming the learning data have been conducted to solve this imbalance problem. In this study, we compared resampling methods among methods to deal with an imbalance in the classification problem. We sought to find a way to more effectively detect the minority class in the data. Through simulation, a total of 20 methods of over-sampling, under-sampling, and combined method of over- and under-sampling were compared. The logistic regression, support vector machine, and random forest models, which are commonly used in classification problems, were used as classifiers. The simulation results showed that the random under sampling (RUS) method had the highest sensitivity with an accuracy over 0.5. The next most sensitive method was an over-sampling adaptive synthetic sampling approach. This revealed that the RUS method was suitable for finding minority class values. The results of applying to some real data sets were similar to those of the simulation.

• ETRI Journal
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• v.8 no.2
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• pp.152-158
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• 1986

최근 전자기기의 소형, 경량화, 다기능화와 고신뢰도 등의 변혁에 따라 이분야의 최적 설계를 위한 설계자동화가 절대적으로 필요로 하는 부분이 되고 있으며 이는 컴퓨터이용 즉, CAD 기술의 중요성이 더욱 인식되고있다. 따라서, 본고에서는 TDX-1 개발을 성공적으로 수행하는데 막중한 역할을 한 CAD 시스팀 구성과 자체 개발한 프로그램 및 앞으로의 추진내용에 대해 기술하였다.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.04a
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• pp.424-436
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• 1993

패널내 추계적 성분들의 공분산 관계(variance-covariance structure)를 이용한 ML 추정법을 항상소득가설(PIH)의 검증에 적용하였다. Hall & Mishkin의 모형을 기초로 분기별 이분산성(heteroscedasticity)을 고려한 모형의 추정결과 전체 소비변동 중 약 11%가 과도민감성에 의한 것으로 나타났다.