• Kyungpook Mathematical Journal
• /
• 제64권2호
• /
• pp.303-309
• /
• 2024

An imaginary bicyclic biquadratic number field K is a field of the form ${\mathbb{Q}}({\sqrt{-m}},{\sqrt{-n}})$ where m and n are squarefree positive integers. The ideal class number h_K of K is the order of the abelian group I_K/P_K, where I_K and P_K are the groups of fractional and principal fractional ideals in the ring of integers 𝒪_K of K, respectively. This provides a measure on how far is 𝒪_K from being a PID. We determine all imaginary bicyclic biquadratic number fields with class number 5. We show there are exactly 243 such fields.

• 한국실내디자인학회논문집
• /
• 제13권1호
• /
• pp.3-10
• /
• 2004

The subject on presentation technique is the class which helps to develop the capability of sensual and creative acts to the students who major in interior design. It helps to understand plasticity and space through the theory of the light and the object, and to develop the capability which realizes one's idea to the actual and visual formations. It also enable the students to explain their designs to the customers by studying the technique which transfers 2D diagram to 3D presentation. Because of these objectives of the class, the departments which major in interior design in Korea consider the class on presentation technique as one of the mun subjects in basic curriculum. However, most of the textbooks related to the presentation technique published in Korea are in the lack of original characteristics for the field of domestic interior design since they refer to or employ the contents of architectural field by directly translating foreign articles. In addition, most of the classes on the presentation technique are taught not by professors but by lecturers so that the class objectives may be varied by their standards for the class. Therefore, it is not easy for each department to set up the one's own characteristics in the field of presentation technique. This study is to analyze the problems in the subjects of presentation technique by investigating the current situations for the subjects on presentation technique in domestic colleges and by surveying the personnels engaged in the field of domestic interior design. Also, the study has the objective to propose the development plan of educational program for the presentation technique in order to enable the student to effectively work in real business.

• 환경위생공학
• /
• 제9권2호
• /
• pp.41-49
• /
• 1994

Water- borne infectious diseases can be acquired by contact with contaminated water or by ingestion of contaminated water. There are many water- borne infectious agents such as bacteria, virus, and parasite. Among many of water- borne infectious diseases, health authorities of Korean government has particularly intensified to prevent and control typhoid fever(class I ), shigellosis(class I ), cholera(class I ), paratyphoid fever(class I), amebiasis(class II ) and leptospirosis(euivalent to class II ) under the communicable disease control law. Water- borne disease Prevention and control guideline itself has been also well provided by the health authorities. However, in practical public health point of view, there are still many problems remained to be solved out; no prospective investigation project to survey water borne infectious diseases under the national disease prevention and control programmes, incredible statistic data of annual notifiable disease report frequent appearance and varieties of drug resistance water- borne infectious agents, little cooperation and information- exchange system in between the related government authorities( the health authorities, the environment sanitation authorities and the food hygiene authorities) which should be closely collaborated, lack of health consciousness of the people, necessity of evaluation and Hndification on to the outcomes of performed health activities and programmes, neglect activities for water quality investigation, shortage of expertise and human resources in the related field, and poor investment of the government budget to develope and improve public health and sanitation field. In order to prevent and control water- borne infectious diseases effectively, it is emphasized that all the above indicated should be considered and performed to improve under the national health and sanitation development programmes.

• 한국초전도ㆍ저온공학회논문지
• /
• 제14권3호
• /
• pp.18-22
• /
• 2012

This paper presents the magnetic field analysis of the racetrack double pancake field coil for the 10 MW class superconducting wind turbine which is considered to be the next generation of wind turbines using the 3 Dimensional FEM(Finite Elements Method). Generally, the racetrack-shaped field coil which is wound by the second generation(2G) superconducting wire in the longer axial direction is used, because the racetrack-shaped field coil generates the higher magnetic field density at the minimum size and reduces the synchronous reactance. To analysis the performance of the wind turbines, It is important to calculate the distribution of magnetic flux density at the straight parts and both end sections of the racetrack-shaped high temperature superconductivity(HTS) field coil. In addition, Lorentz force acting on the superconducting wire is calculated by the analysis of the magnetic field and it is important that through this way Lorentz force can be used as a parameter in the mechanical analysis which analyzes the mechanical stress on the racetrack-shaped field coil.

• 호남수학학술지
• /
• 제30권1호
• /
• pp.53-64
• /
• 2008

Lower dimensional cases of Einstein's connection were already investigated by many authors for n = 2, 3, 4, 5, 6. In the following series of two papers, we present a surveyable tensorial representation of 8-dimensional Einstein's connection in terms of the unified field tensor: I. The recurrence relations in 8-g-UFT II. The Einstein 's connection in 8-g-UFT In our previous paper [1], we investigated some algebraic structure in Einstein's 8-dimensional unified field theory (i.e., 8-g-UFT), with emphasis on the derivation of the recurrence relations of the third kind which hold in 8-g-UFT. This paper is a direct continuation of [1]. The purpose of the present paper is to prove a necessary and sufficient condition for a unique Einstein's connection to exist in 8-g-UFT and to display a surveyable tensorial representation of 8-dimensional Einstein's connection in terms of the unified field tensor, employing the powerful recurrence relations of the third kind obtained in the first paper [1]. All considerations in this paper are restricted to the first class only of the generalized 8-dimensional Riemannian manifold $X_8$, since the cases of the second class are done in [2], [3] and the case of the third class, the simplest case, was already studied by many authors.

• 호남수학학술지
• /
• 제27권1호
• /
• pp.131-140
• /
• 2005

Lower dimensional cases of Einstein's connection were already investigated by many authors for n = 2, 3, 4, 5, 6, 7. In the following series of two papers, we present a surveyable tensorial representation of 8-dimensional Einstein's connection in terms of the unified field tensor: I. The recurrence relations in 8-g-UFT II. The Einstein's connection in 8-g-UFT In our previous paper [1], we investigated some algebraic structure in Einstein's 8-dimensional unified field theory (i.e., 8-g-UFT), with emphasis on the derivation of the recurrence relations of the third kind which hold in 8-g-UFT. This paper is a direct continuation of [1]. The purpose of the present paper is to prove a necessary and sufficient condition for a unique Einstein's connection to exist in 8-g-UFT and to display a surveyable tensorial representation of 8-dimensional Einstein's connection in terms of the unified field tensor, employing the powerful recurrence relations of the third kind obtained in the first paper [1]. All considerations in this paper are restricted to the second class only of the generalized 8-dimensional Riemannian manifold $X_8$, since the case of the first class are done in [2], [3] and the case of the third class, the simplest case, was already studied by many authors.

• 대한수학회논문집
• /
• 제12권3호
• /
• pp.553-560
• /
• 1997

A class number formula over global function field, extending the formula obtained by Shu, is proved.

• 정보처리학회논문지A
• /
• 제11A권5호
• /
• pp.319-324
• /
• 2004

자바 언어는 빠른 속도로 인터넷 및 분산 응용 분야 등에서 활용되고 있으며 단순히 응용 소프트웨어를 개발할 수 있는 프로그래밍 언어이상으로 활용 범위가 확대되고 있다. 특히, 실행 환경인 자바 가상 기계에 연관되어 다양한 연구가 진행되고 있으며 자바 클래스 파일에 대한 분석 및 응용 분야에 적합한 형태로 정보를 활용할 수 있는 다양한 시도가 진행되고 있다. 자바 언어에 대한 클래스 파일은 소스 프로그램의 의미를 자바 가상 기계에서 실행 가능한 형식으로 변환된 형태이다. 이러한 클래스 파일의 구조 및 실질적인 실행 과정에 대한 분석은 디컴파일러 구성, 소스 프로그램의 디버깅 등에 편리성을 지원할 수 있다. 본 논문에서는 이러한 클래스 파일에 대한 분석을 비롯하여 실제로 실행되는 과정을 보다 시각적으로 표현하기 위한 실행 분석기 개발에 관한 연구이다 이를 위해 클래스 파일의 내용을 GUI 환경에서와 같이 접근 및 표현이 용이하도록 구현하였다. 클래스 파일이 포함하고 있는 정보들을 Constant_Pool 부분, Class_file 부분, Interface 부분, Field 부분, Method 부분, Attribute 부분으로 나뉘어서 나타내도록 해주었다. 또한 클래스 파일의 실행 과정에서 핵심 정보를 저장하고 있는 메소드 영역 정보, 오퍼란드 스택 정보, 지역 변수의 정보를 시각적으로 표현하였다.

• 한국초전도ㆍ저온공학회논문지
• /
• 제4권1호
• /
• pp.55-60
• /
• 2002

$100 A/mm^2$ class Bi-2223 tapes have recently become commercially available. Some important characteristics of the tapes, e .g. critical current, ac loss, characteristics at joint, fault current characteristics, are required for an application such as a power cable or a power transformer. In this paper they have been investigated experimentally. The results indicate that the self-field loss of the high current density tapes is not negligible, compared to resistive loss in a copper wire for the same currents. In a cable, the self-field loss for relatively large currents is much larger than the magnetization loss due to an external field. But in a transformer, the magnetization loss is dominant, compared to the self-field loss. Finally the fault current characteristics show that the high current density tapes are never safe from burn-out even for fault currents with a few cycles.

• 대한수학회지
• /
• 제50권4호
• /
• pp.847-864
• /
• 2013

By a change of variables we obtain new $y$-coordinates of elliptic curves. Utilizing these $y$-coordinates as meromorphic modular functions, together with the elliptic modular function, we generate the fields of meromorphic modular functions. Furthermore, by means of the special values of the $y$-coordinates, we construct the ray class fields over imaginary quadratic fields as well as normal bases of these ray class fields.