Pekeris 도파관에서 음선 접근법을 이용한 지면파 해석

최지웅,Choi, Jee-Woong 한국음향학회 2009 韓國音響學會誌 Vol.28 No.3

지면파는 해저면 음속이 깊이에 따라 일정할 경우 해저면 음속으로 진행하는 음파로 일반적으로 모드분산으로부터 설명된다. 모드분산은 도파관의 기하학적 구조에 의한 음파의 반사 및 굴절에 의해 발생되므로 본 논문에서는 지면파를 음선이론에 기초하여 모의하였다. 지면파는 일련의 선두파들의 조합으로써 해석될 수 있으므로 [Choi와 Dahl, J. Acoust. Soc. Am. 119, 3660-3668 (2006)], 음선 접근법을 이용하여 시간영역에서 여러 경로로 전파되는 선두파들의 채널 임펄스 응답과 선두파 신호의 컨볼루션을 취하여 지면파를 모의한다. 모의된 지면파는 광대역 시간영역 포물선 방정식 기법을 이용하여 모의된 지면파와 비교, 검증된다. Ground wave is an acoustic wave propagating at a sediment sound speed in the case that sediment sound speed is constant with depth, which is explained by modal dispersion effects. In this paper, the ground wave in time domain is simulated using the ray-based approach, which is possible because the modal dispersion can be explained by the guiding of energy caused by reflection and refraction in the waveguide geometry. For a Pekeris waveguide, the ground wave can be interpreted as a sequence of head waves, called a head wave sequence [Choi and Dahl, J. Acoust. Soc. Am. 119, 3660-3668 (2006)]. The ground wave is simulated by convolution of the source signal with a channel impulse response of the head wave sequence, which is compared with simulated signals obtained via a Fourier synthesis of a complex parabolic equation (PE) field.

1910년대 조선에서 자유주의의 두 가지 유형과 성격

최선웅(Choi, Sun?woong) 호서사학회 2015 역사와 담론 Vol.0 No.75

응급실내에서 발생한 폭력의 실태

최웅지,조남수,조수형,김성중,박광철,박진실 朝鮮大學校 附設 醫學硏究所 2004 The Medical Journal of Chosun University Vol.29 No.1

Background and Objectives: The objective of this study was to obtain circumstances about violence providers and cause of the violence in emergency room. Materials and Methods: Reports were provided to emergency department doctors, nurses and emergency medical technicians working in Chosun University Hospital Emergency Center during the sixty days from 26 May 2003 to 24 July 2003. Report form consisted of the degree of violence, the reason for the violence, dermographic information about violence providers, outbreak time of violence and response of emergency personnels. Results: SixtyUeight case of violence in the emergency department were reported. Almost all of the violence was due to the male gender and high incidence in third and fourth decade. The violence occured mostly in the night shift. 55.9% of violence was done by patient and 41.2% was done by patient's guardians. The leading cause of violence were alcohol drunken and delay of laboratory test and treatment. Verbal abuse and threats were the most concern form of violence, Conclusion: It is necessary to solve the problems faced in the emergency department not only administrative and financial aid but also regular preventive education and further study.

우수골프 선수들의 부위별 등속성 근력의 요인분석

최웅재 한국학교체육학회 2002 한국학교 체육학회지 Vol.12 No.2

본 연구는 골프에 대한 전문적인 체력이 있다고 판단되는 골프선수 33명을 대상으로 기본체력 요인 중에서의 근력요인을 Cybex-6000등속성 장비를 이용하여 골프선수의 근력요인을 분석하였다. 근력요인 분석시 상지, 몸통, 하지의 3가지의 큰 부분으로 나누어서 총 14개의 항목을 측정하였고 이들 체력요인 측정결과를 토대로 요인분석 방법을 적용하여 요인구조를 분석하였다. 이 결과 얻어진 곁론은 골프 선수들에게 있어서 높은 부하를 보이는 근력요인은 각근져 60˚ /sec Extension Right(8.69%), Extension Left(8.52%), Flexion Right(6.71%), flexion Left(6.43%)로 나타났다. 그 다음으로 비중을 차지하는 요인은 어깨60˚ /sec Adduction Right(4.98%), Adduction Left(4.58%), 트렁크 30˚ /sec Extension(4.04%), 완력 60˚ /sec Flexion Left(3.37%)의 순으로 나타났다. 이러한 여러 가지의 결과로 볼 때에 모든 운동종목의 기본이 되는 근력요인은 골프 경기에서도 클럽의 제어 및 비거리, 방향성 등과 직결되는 중요한 요인이므로 선수들의 운동프로그램 작성시 위에서의 높은 부하요인이 나온 부분을 우선순위로 근력 운동프로그램을 작성하면 보다 효율적인 경기력이 나을 것으로 사료된다. This study analyzed the factors of muscular strength among those of basic fitness, based on the 33 pro golfers considered as having the professional physical strength for the golf utilizing Cybex-6000, the uniform velocity equipment. At the time of analyzing the factors of muscular strength, after dividing a body into the upper limbs, middle body, and the lower limbs as the parts, the 14 items of each part were approximately measured, and the structure of factors was analyzed applying the method of factor analysis based on the result of muscular strength measurement. The result showed that the factor of proving high loading rate with the golfers was leg strength 60˚ /ser Extension Right (8.69%), Extension Left (8.52%), Flexion Right (6.71%), and flexion Left (6.43%). As the second loading rate-factor, the result showed shoulder 60˚ /sec Adduction Right (4,98%), Adduction Left (4.58%), trunk 30˚ /sec Extension (4.04%), arm strength 60˚ /sec Flexion Left (3.37%) in hierarchy. Regarding these results, the muscular strength factors which are the basic elements for every sports entry are the gave factors that affect the control of club, distance, vector. So when making excercise programs for athletes, if the programs make advantage of the result found in this study, more efficient contesting ability.

陶淵明 田園詩의 美的體驗에 대하여

崔雄赫 대구효성 가톨릭대학교 1994 연구논문집 Vol.48 No.1

陶淵明 田園時의 形成背景 : 陶淵明의 田園時 硏究(Ⅲ)

崔雄赫 대구효성가톨릭대학교 외국어문학연구소 1990 語文學硏究 Vol.3 No.-

참당귀(Angelica fifas Nakai)의 캘러스로부터 체세포배 발생에 미치는 계대배양 주기의 영향

최용의,소웅영 全北大學校 基礎科學硏究所 1994 基礎科學 Vol.16 No.-

Embryogenic callus was produced form leaf segments cultured on medium containing 1.0 mg/L 2,4-D. The callus gave rise to somatic embryos after transfer the embryogenic callus to medium without 2,4-D. Also, somatic embryogenesis occured from aged callus on medium containing 2,4-D. To investigate the effects of culture periods on somatic embryogenesis the embryogenic calli were cultured for 2, 4, 6 and 8 weeks on medium containing 1.0 mg/l 2,4-D and then transferred to medium with or without 2,4-D. In prolonged preincubation, somatic embryos were formed early and at high frequency and their development normally occured. When subcultured on medium containing 2,4-D, the callus preincubated for 6 to 8 weeks was capable of producing somatic embryos. Histological observation revealed that 4 weeks-old embryogenic callus on medium containing 2,4-D was composed of mainly typical embryogenic cells, whereas the 8-weeks-old callus was composed of nonembryogeinc cells and that. In the developing state of somatic embryo on medium without 2,4-D, all the cells of callus were in vacuolated and elongated except developing somatic embryos.

합기도 참여와 스포츠 태도의 관계

최웅재 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

This paper studied the relationship between The Relationship Between Participated in Hapgido And Sport Attitudes of Children. To attain the goal of the study described above paragraphs, Children's Hapgido participants in Daejeon 2004. Then, using the stratified random Sampling methods, finally drew out 292 participants. The material collection device was the brochure named <The relationship between The Relationship Between Participated in Hapgido And Sport Attitudes of Children>, To analyze materials, the one-way "ANOVA" was used as statistic analysis techniques. The conclusion based on above study method and the result of material analysis are here blew. First, Children's Hapgido participation frequency is positive Sport Attitudes of Children. Second, Children's Hapgido participation density is positive Sport Attitudes of Children. Third, Children's Hapgido participation interval is positive Sport Attitudes of Children.

접착강화제가 치아경조직과의 접척강도 변화에 미치는 영향에 관한 연구

최웅대,박상진 大韓齒科保存學會 1995 Restorative Dentistry & Endodontics Vol.20 No.1

AbstractThe purpose of this study was to investigate the effect of dentin bonding agents on the bond strength of composite resin restorations in case of applying the dentin bonding agents to acid etched enamel surfaces. Freshly extracted 364 bovine anterior teeth were selected as a adherents. 320 enamel specimens were divided into two groups(unetched group (D and etched group ?for testing the shear bond strength, 40 specimens were used for the hardness testing, and 4 specimens of rest were to observe the resin-tag forma- tion into etched enamel surfaces.All surfaces of enamel specimens were polished with 320~1500 SiC paper under conti- nuous running water. In Group (D, 100 enamel specimens were polished and unetched. 220 polished enamel specimens in Group ?were etched with 37% phosphoric acid solution for 60 seconds, washed with water for 20 seconds, and dried with a light air pressure for 60 seconds.Three kinds of dentin bonding agents( Gluma, Prisma, Scotchbond 2) were evaluated the effect on the bond strength to conditioned enamel surfaces. Shear bond strengths were measured on the three cases such as a coating of primer only, a coating of sealer only, and a sequential coating of primer and sealer to acid etched enamel surfaces were compared with the bond strengths measured by the coating of enamel bonding agent followed by the bonding of composite resin (Photo clearfil bright, Kuraray, Japan) to unetched and acid etched enamel surfaces.In addition, the hardness tested on the adhesive fractured surface between composite resin enamel as a mean of evaluation of a factor whether the mechanical bond strengths were affected and the penetration of dentin bonding agents into etched enamel surfaces was also observed. Bond strengths were measured using the method of shear bond strength by a universal testing machine (Instron-4467, USA), statistical test were applied to the results using a one way analysis variance (ANOVA), and hardness was measured by the Vicker's Hardness Tester(MHT-i, Matsuzawa, Japan) and the penetration of the resins were observed by the SEM (Hitachi, S-2300, Japan).The following conclusions were drawn ; 1. Enamel bonding agent showed to affect the improvement of bond strength of composite resin to enamel surface both unetched and etched. 2. Dentin bonding agents could be resulted in increase of bond strength to unetched enamel surface, but there were no statistical significances. 3. Bond strengths to etched enamel surface were significantly decreased with a coating of dentin primer only. 4. Coating of sealer only and coating of primer and sealer noticed the similar bond strengths of composite resin to etched enamel using the enamel bonding agents. 5. The applying method proved to be more effective than the kinds of dentin bonding agents on the bond strength of composite resin to etched enamel than the kind of dentin. 6. Vicker's hardness numbers of dentin bonding agents were lower than that of composite resin, but the degree of penetration of dentin bonding agents into etched enamel surfaces was excellent.

레이저 照射後 臼齒用 복합레진의 結合力에 關한 硏究

최웅진 全北大學校 齒醫學硏究所 1991 전북치대논문집 Vol.9 No.1

The purpose of this sutdy was investigating the bond strength between composite resin and enamel surface of the tooth. The enamels of sound primary molars and permanent premolars were used for experiment. They were extracted for orthodontic therapy or at physiologic exfoliation. They were classified into 10 groups at random ; 1 control group, 4 experimental groups were contained in self-curing resin and light-curing resin each. Laser impacts on each experimental groups were made at energy density of Q-switched Nd : YAG laser with 3.6J/m^2 and 10.8J/cm^2, Giant pulsed Nd : YAG laser 40J/cm^2 and Normal pulsed Nd : YAG laser with 40J/cm^2. Then the decalcified patterns of enamel by 36% phosphoric acid were investigated with scanning electron microscope add adhesive shear strength was measured on the each decalcified enamel surface after adhesion of light-curing and self-curing resin. All the decalcified enamel surfaces were classified into 3 groups and the hardness change after laser irradiation was examined. The obtained results were as follows. 1. There were not significant difference statistically between the light-curing resin groups in adhesive shear strength of primary molar(P>0.05), but significant increase in bonding force of self-curing resin groups as significant level α=0.05 in Q-switched Nd : YAG laser with 3.6J/cm^2, significant level α=0.01 in Normal pulsed Nd : YAG laser with 40J/cm^2. 2. There were not significant difference statistically between the light-curing resin groups in adhesive shear strength of permanent premolar, but significant increase in bonding force of self-curing resin groups as significant level α=0.05 in Q-switched Nd : YAG laser with 10.8J/cm^2 and Normal pulsed Nd : YAG laser with 40J/cm^2. 3. There were significant increase in bonding force of self-curing resin groups(α=0.01) in contrast to light curing resin groups when adhesive shear strength was examined with primary molar and permanent premolar. 4. In the hardness change after laser irradiation. primary molar was decreased significantly only in irradiation of Normal pulsed Nd : YAG laser as significant level α=0.01(P<0.01). In case of permanent premolar, significant decrease was seen statistically as significant level α=0.05 in Giant pulsed Nd : YAG laser irradiation and significant level α=0.01 in normal pulsed Nd : YAG laser irradiation(P<0.01).