수학사적 관점에서 오일러 및 베르누이 수와 리만 제타함수에 관한 탐구

김태균,장이채,Kim, Tae-Kyun,Jang, Lee-Chae 한국수학사학회 2007 Journal for history of mathematics Vol.20 No.4

베르누이가 처음으로 자연수 k에 대하여 합 $S_n(k)=\sum_{{\iota}=1}^n\;{\iota}^k$에 관한 공식들을 유도하는 방법을 발견하였다([4]). 그 이후, 리만 제타함수와 관련된 베르누이 수와 오일러 수에 관한 성질들이 연구되어왔다. 최근에 김태균은 $\mathbb{Z}_p$상에서 p-진 q-적분과 관련된 확장된 q-베르누이 수와 q-오일러 수, 연속된 q-정수의 멱수의 합에 관한 성질들을 밝혔다. 본 논문에서는 연속된 q-정수의 멱수의 합에 관한 역사적 배경과 발달과정을 고찰하고, 오일러 및 베르누이 수와 관련된 리만 제타함수가 해석적 함수로써 값을 가지는 문제를 q-확장된 부분의 이론으로 연구되어온 q-오일러 제타함수에 대해 체계적으로 논의한다. J. Bernoulli first discovered the method which one can produce those formulae for the sum $S_n(k)=\sum_{{\iota}=1}^n\;{\iota}^k$ for any natural numbers k. After then, there has been increasing interest in Bernoulli and Euler numbers associated with Riemann zeta functions. Recently, Kim have been studied extended q-Bernoulli numbers and q-Euler numbers associated with p-adic q-integral on $\mathbb{Z}_p$, and sums of powers of consecutive q-integers, etc. In this paper, we investigate for the historical background and evolution process of the sums of powers of consecutive q-integers and discuss for Euler zeta functions subjects which are studying related to these areas in the recent.

기계적 자극에 대한 백서 치주인대 섬유아세포의 변화

김태균,김창성,조규성,채중규,김종관,최성호,Kim, Tae-Gyun,Kim, Chang-Sung,Cho, Kyoo-Sung,Chai, Jung-Kiu,Kim, Chong-Kwan,Choi, Seong-Ho 대한치주과학회 2001 Journal of Periodontal & Implant Science Vol.31 No.2

Periodontal disease is characterized by inflammation and subsequent loss and/or damage to tooth-supporting tissues such as bone, cementum,and periodontal ligament. Periodontal ligament and cementum are the key tissues in the initial process of regeneration following periodontal disease. Therefore, studies on cementoblasts, which form cementum are emphasized. It is still unclear which cells cementoblast differentiate from. This study was conducted under the hypothesis that PDL fibroblast can differentiate into either cementoblast or osteoblast depending on the conditions of surrounding tissue. Clinically, with excessive traction force of orthodontic appliances or excessive occlusion hypercementosis is observed, and this has been confirmed histologically. Consequently, activation of cementoblast can be expected in rats when mechanical stimuli are given to PDL fibroblast. Therefore, the purpose of this article is to prove that PDL fibroblast differentiates into cementoblast in rats under mechanical stimuli using histologic and molecular methods. In this study, twenty rats were given hard diet. Ten of them were sacrificed after 1 week, and the others were sacrificed after two weeks. Slides were made from tooth specimen, and they were studied under the microscope. In addition, PDL fibroblast and cementum from the extracted teeth were analyzed with Northern blotting. In histologic examination, as time passed, PDL fibroblast migrated to the dentin side, differentiated into cementoblast, and formed new cementum. In Northern blotting, it was found that mRNA expression of cementoblast-specific proteins such as BSP, OC, OPN, and type I collagen were more prominent in rats sacrificed after 2 weeks of hard-diet than rats sacrificed after 1 week. From these findings we can conclude that PDL fibroblast can differentiate into cementoblast under mechanical stimuli. We think that 'Rat Models' used in this study will be beneficial to future studies regarding cementoblast.

택지조성원가와 발생원가의 오차에 관한 실증연구 : 택지개발사업지구를 중심으로

김태균,장인석,이덕복,김옥연,Kim, Tae-Gyun,Chang, In-Seok,Lee, Duck-Bok,Kim, Ok-Yon 한국토지주택공사 토지주택연구원 2012 LHI journal of land, housing, and urban affairs Vol.3 No.1

현행 우리나라 택지조성원가 산정체계는 택지조성과정에서 준공이전에 추정한 조성원가와 조성과정에서 돌발적으로 발생하는 변동요인이 고려된 준공시의 발생원가로 구분된다. 따라서 두 원가사이에 발생되는 격차로 인해 분양가격에 영향을 미치는 발생원가는 산정체계에 대한 문제점을 지적 받아오고 있으므로 발생원가의 객관성을 높이기 위해서는 예측가능한 돌발상황에 대해 조성원가 산정시 반영되는 방안이 모색되어야 한다. 이에 본 연구에서는 조성원가와 발생원가 사이에 발생되는 격차율 가운데 예측이 가능한 규모를 유효격차율로 정의하고 각 사업지구의 다양한 특성을 고려한 유효격차율을 추정하고자하였다. 따라서 각 사업지구의 다양한 특성을 유형으로 분류하기 위해 5개의 주제별 카테고리를 설정하고, 카테고리들을 복합화한 복합카테고리를 이용하여 유효격차율을 추정하고자 하였으며 추정모형 검정결과 신뢰성이 매우 높은 것으로 분석되었다. 향후 지속적인 자료축척으로 안정화된 추정모형의 유효격차율이 조성원가에 반영되었을 경우 발생원가와의 격차해소에 기여할 것으로 기대된다. The current land development cost price system is classified as the creating land by construction price and composition changes that occur sporadically in the process of completion at the source of the factors by incurred cost price. Housing for land cost price system is a lack of objectivity which scheme of the such a gap due to the land in accordance construction and incurred cost price system so far. Therefore, in order to increase the objectivity of costing the costing of predictable surprises should be reflected in the process. Under such a background, this study defined the effective differential ratio as the predictable, estimated them for various characteristics of each business district to reflect. For this, set the properties category of five types to attributes and making the complex category and Look-up table. Which result of model validation is showed a high reliability. Therefore, Continuous accumulation of material in the future, when them to reflect the construction cost, will contribute to the bridge the gap the construction cost between incurred them.

몬테카를로 위치추정 알고리즘을 이용한 수중로봇의 위치추정

김태균,고낙용,노성우,이영필,Kim, Tae-Gyun,Ko, Nak-Yong,Noh, Sung-Woo,Lee, Young-Pil 한국전자통신학회 2011 한국전자통신학회 논문지 Vol.6 No.2

본 논문에서는 몬테 카를로 방법을 사용한 수중로봇의 위치추정 방법을 제안한다. 수중로봇의 위치추정은 자율 주행을 위한 기본 기능의 하나이다. 제안된 알고리즘에 의하면 추측항법(데드 레크닝 방법)의 약점인 위치 오차 누적 문제를 해결할 수 있다. 제안된 방법은 확률적인 방법으로 로봇 동작의 불확실성과 센서 정보의 불확실성을 처리한다. 특히 칼만 필터 방법과 달리, 로봇의 비선형 운동 특성과 센서의 비가우시안 출력 분포 특성을 모델링할 수 있다. 본 논문에서는 수중로봇 위치 추정에 몬테카를로 위치추정(Monte Carlo Localization : MCL, 이하 MCL로 표기함) 알고리즘을 적용하기 위하여 오일러각을 이용하여 모션모델을 구하였다. 또한 수중로봇에 모션모델과 센서모델을 적용하여 시뮬레이션을 구현하고, 이를 통해 수중로봇에 MCL 알고리즘의 적용 가능성을 보였다. The paper proposes a localization method of an underwater robot using Monte Carlo Localization(MCL) approach. Localization is one of the fundamental basics for autonomous navigation of an underwater robot. The proposed method resolves the problem of accumulation of position error which is fatal to dead reckoning method. It deals with uncertainty of the robot motion and uncertainty of sensor data in probabilistic approach. Especially, it can model the nonlinear motion transition and non Gaussian probabilistic sensor characteristics. In the paper, motion model is described using Euler angles to utilize the MCL algorithm for position estimation of an underwater robot. Motion model and sensor model are implemented and the performance of the proposed method is verified through simulation.

지역 및 기능적 특성을 고려한 복합환승시설 유형분류

김태균,이삼수,변완희,Kim, Tae-Gyun,Lee, Sam-Su,Byun, Wan-Hee 한국토지주택공사 토지주택연구원 2013 LHI journal of land, housing, and urban affairs Vol.4 No.1

In recent years, it was recognized that aurban policy paradigm of sustainable urban growth management and transportation policies have been shifted : from the era of automobile-oriented policy to the era of public transport policy. Against this backdrop, the introduction of the multi-modal transfer center is very consequential. Therefore, it is necessary for the introduction of wide-area and local-centric transfer facilities, as well as the center of the country-led national backbone transfer center. This study was applicable at the multi-modal transfer center plans to introduce guidelines to provide transit facilities, considering the regional and functional characteristics to classify the types of multi-modal transfer center. The final types of multi-modal transfer center were classified into six, and by considering the combination of the criteria to be classified. The multi-modal transfer center type classification based on the case analysis of the types of facilities at domestic and abroad. If the data of multi-modal transfer are accumulated continuously, can expect a more reliable type classification. 최근 도시의 정책적 패러다임이 지속가능한 도시성장관리 중심으로 전환됨에 따라 교통정책도 승용차중심에서 대중교통중심으로 정책변화가 요구되고 있다. 이러한 배경 하에 복합환승센터의 도입은 매우 필연적이라고 볼 수 있다. 따라서 국가에서 주도하는 국가기간망중심의 환승센터 뿐 만 아니라 광역 및 지역중심의 환승시설에 대한 도입도 필요한 실정이다. 이에 본 연구에서는 효과적인 복합환승시설 도입을 위해 다양한 지역적 특성(영향권, 입지위치, 도시규모, 도시기능)과 환승시설기능(환승공간 이용방법, 연계교통수단)을 고려하여 66개의 사례를 유형화하였다. 또한 통계적인 유의성 검정을 통해 영향권-연계교통수단-도시기능조합과 도시규모-입지위치조합의 2가지 복합화된 유형을 제시하였다. 유형분류를 이용한 기존의 66개 사례지역을 정리해 본 결과 국내외 모두 비교적 규모가 큰 대도시를 중심으로 지역간 연계를 기반으로 하는 복합환승시설이 주류를 이루고 있음을 알 수 있다. 본 연구의 결과를 통해 향후 복합환승시설에 대한 자료가 지속적으로 축적되어질 경우 좀 더 신뢰성이 높은 유형분류의 결과를 기대해 본다.

팔라디움-은합금의 반복주조시 도재와 금속간의 화학적 결합에 관한 실험적 연구

김태균,이선형,양재호,정헌영,Kim, Tae-Kyun,Lee, Sun-Hyung,Yang, Jae-Ho,Chong, Hun-Young 대한치과보철학회 1989 대한치과보철학회지 Vol.27 No.1

The purpose of this study was to evaluate the chemical bond strength of successively recast Pd-Ag ceramic alloys with porcelain and to investigate changes of quantity of trace elements at the metal-porcelain interface. Porcelain was fired as usual manner on the each successively recast specimen. Rectangular planar shear test was performed and bond strength was measured by Instron universal testing machine. Diffusion of trace elements at the each interface was observed by ESCA (Electron Spectroscopy for Chemical Analysis). The obtained results were as follows : 1. Chemical bond strength was significantly decreased after second recasting. But in case of first recasting, there was no significant decrease of bond strength statistically (p<0.05). 2. Bond strength was not significantly decreased in each generation, when fifty percents new alloy was added (p<0.05). 3. Ag, Sn and In were observed at the porcelain interface. But Pd was not observed. 4. The quantity of Ag, In ions were progressively increased at the metal-porcelain interface as the casting was repeated. Silver ion was most significantly increased.

임프란트를 이용한 고정성 계속가공의치의 FRAMEWORK 형태에 관한 연구

김태균,이영수,유광희,Kim, Te-Gyun,Lee, Young-Soo,Yoo, Kwang-Hee 대한치과보철학회 1998 대한치과보철학회지 Vol.36 No.1

The purpose of this study was pertinent design of the framework of the fixed bone anchored bridge using implants in the edentulous mandible through analysis of stress distribution by the three dimensional finite element analysis method. The results were as follows: 1. The L-shaped framework was favorable in restoring the edentulous mandible by implants and fixed bone anchored bridge. 2. The structure of the framework should be designed to endure the occlusal load because of stress concentration at the most distal abutment of the framework. 3. The stress at the distal implant where cantilever starts was twice as much as that of other portions. 4. Compressive stress was generated on the framework of the mesial side of the distal implant and extrusive force was induced to the mesially positioned implants. 5. The height of vertical plate was high as possible as can be to distribute stresses concentrating bucco-lingually and labio-lingually in the framework between abutments, 6. Reinforcement of the horizontal plate thickness was needed because stress was loaded more on the horizontal plate than on the vertical plate of the framework. 7. Lengthening of the vertical plate can compensate for any limitations in horizontal plate width.

설측 슬롯을 부여한 임플란트 고정성 보철물에서 내면 간격이 유지력에 미치는 영향

김태균,이규복,Kim, Tae-Kyun,Lee, Kyu-Bok 대한치과보철학회 2018 대한치과보철학회지 Vol.56 No.3

목적: 최근 임플란트 고정성 보철물 제작 시 나사 유지형 보철물의 교합적, 심미적 단점을 해결하고, 시멘트 유지형 보철물에서 착탈 용이성을 확보하기 위하여 보철물 설측에 슬롯을 형성하는 방법이 소개되었다. 이 연구의 목적은 설측 슬롯을 부여한 시멘트 유지형 임플란트 보철물 제작 시에 내면 간격이 보철의 제거에 어떤 영향을 미치는지 알아보는 것이다. 재료 및 방법: 티타늄 지대주와 상부에 합착할 지르코니아 보철물 내면 간격을 30, 35, $50{\mu}m$의 3종류로 설정하여 종류별로 3개씩 총 15개를 제작하였다. 지르코니아 보철물은 티타늄 지대주의 선반 부위와 만나는 위치에서 1 mm의 공간이 생기도록 하여 탈착을 위한 슬롯(retrievable cement-type slot, RCS)을 형성하였다. 지대주와 지르코니아 보철물의 합착에는 자가 중합 레진 시멘트를 이용하였고, 합착 된 시편을 맞춤 제작된 장비를 이용하여 최대 제거 응력 값을 Ncm단위로 측정하였다. 통계적 분석으로 세 그룹을 비교하기 위해 Kruskal-Wallis 검정을 시행하였고 (${\alpha}=.05$), 사후검정으로 수정된 Mann-Whitney U-test와 Bonferroni correction 방법을 이용하여 차이를 보았다 (${\alpha}=.017$). 결과: 내면 간격이 $30{\mu}m$ 군과 $35{\mu}m$ 군간의 비교에 있어서 제거 응력에 통계학적으로 유의한 차이가 없었고 (P = .032), $30{\mu}m$군과 $50{\mu}m$군, $35{\mu}m$군과 $50{\mu}m$군간을 비교 할 때 유의한 차이가 나타났다 (P < .017). 결론: 그러므로 내면 간격은 지르코니아 보철물과 티타늄 지대주 사이의 유지력에 영향을 미쳤다. Purpose: Recently, a method of forming a slot in the prosthesis lingual has been introduced to solve the occlusal and aesthetic disadvantages of screw-retained prosthesis in the manufacture of implant-fixed prosthesis and to ensure retrievability in cement retained prostheses. The purpose of this study is to investigate the effect of the internal gap on the removal of the prosthesis in the preparation of cement-retained implant prostheses with lingual slots. Materials and methods: Titanium abutment and internal gap of the zirconia prosthesis to be attached to the upper part were set to 30, 35, and $50{\mu}m$, respectively. Three for each type total 15 were produced for each type. The zirconia prosthesis formed a retrievable cement-type slot with a space of 1 mm at the location where the titanium abutment meets the shelf area. Autocatalytic resin cement was used for bonding of abutment and zirconia prosthesis, and the maximum removal stress value was measured in units of Ncm by using the customized equipment of the cemented specimen. The Kruskal-Wallis test was used to compare the three groups by statistical analysis (${\alpha}=.05$), modified by post hoc test the Mann-Whitney U-test and the Bonferroni correction method were used to compare the two methods (${\alpha}=.017$). Results: There was no statistically significant difference in removal stress between the $30{\mu}m$ group and the $35{\mu}m$ group in the internal gap (P = .032), and there was a significant difference between the $30{\mu}m$ group and the $50{\mu}m$ group, between the $35{\mu}m$ group and the $50{\mu}m$ group (P < .017). Conclusion: Thus, the internal gap of computer-aided design affected the retention between the zirconia prosthesis and the titanium abutment.

초소형 압축기용 초고속 전동기 내부의 복합 열전달 해석

김태균,허남건,정시영,전승배,Kim, T. G.,Hur, N.,Jeong, S.,Jeon, S. B. 한국유체기계학회 2001 한국유체기계학회 논문집 Vol.4 No.1

In a small centrifugal compressor system, a high-speed motor needs to be developed to drive impellers directly. Heat is generated by both electrical heating due to copper coil resistance and aerodynamic heating in the gap between the rotor and stator in a high-speed motor. Removal of the heat is essential to the design of such motors since most magnetic materials are brittle and can be easily fractured by the heat. In the present study the cooling flow fields and temperature distributions are analyzed by using computational fluid dynamics simulation for a high-speed motor which has air cooling system as well as water cooling system. In the analysis, a conjugate heat transfer problem is solved by considering both convective heat transfer in the cooling system and conduction heat transfer in solid parts. Based on design drawings of a motor, air cooling system and water cooling system are analyzed to obtain temperature field and thus to check the coiling system performance. Also the cooling performance are studied for various flow rates of cooling air and water at the inlets.

우유의 경제적 감가상각 방법

김태균,최태길 ( Tae Kyun Kim,Tae Kil Choi ) 한국축산경영학회 1994 韓國畜産經營學會誌 Vol.10 No.1