• 대한수학회보
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• 제40권2호
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• pp.223-234
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• 2003

This note contains the following results for a ring A : (1) A is simple Artinian if and only if A is a prime right YJ-injective, right and left V-ring with a maximal right annihilator ; (2) if A is a left quasi-duo ring with Jacobson radical J such that $_{A}$A/J is p-injective, then the ring A/J is strongly regular ; (3) A is von Neumann regular with non-zero socle if and only if A is a left p.p.ring containing a finitely generated p-injective maximal left ideal satisfying the following condition : if e is an idempotent in A, then eA is a minimal right ideal if and only if Ae is a minimal left ideal ; (4) If A is left non-singular, left YJ-injective such that each maximal left ideal of A is either injective or a two-sided ideal of A, then A is either left self-injective regular or strongly regular : (5) A is left continuous regular if and only if A is right p-injective such that for every cyclic left A-module M, $_{A}$M/Z(M) is projective. ((5) remains valid if 《continuous》 is replaced by 《self-injective》 and 《cyclic》 is replaced by 《finitely generated》. Finally, we have the following two equivalent properties for A to be von Neumann regula. : (a) A is left non-singular such that every finitely generated left ideal is the left annihilator of an element of A and every principal right ideal of A is the right annihilator of an element of A ; (b) Change 《left non-singular》 into 《right non-singular》in (a).(a).

• 대한기계학회논문집
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• 제18권3호
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• pp.768-776
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• 1994

This paper describes computer-aided forging design for rib/web shaped parts. In manufacturing a part by means of forging process, the first step is to design the forging. This is done by modifying the given machined part geometry according to the requirements of the forging process. Traditionally, this is done by experienced forging designers using empirical forging design guidelines. Generally, it would be neither possible nor practical to develop a system which encompasses the design of all types of forgings. Accordingly, forging design can be simplified by considering critical two dimensional cross sections of the machined part geometry. This system is composed of three modules(process variable decision module, forging design module and redesign module) and each module is carried out in regular sequence. In the process variable decision module, first of all, the undercut is checked and modified, and then deep recesses and holes difficult to forge are eliminated. Also parting line, forging plane, forging plan view area, forging weight and maximum size(maximum height or width)are determined. In the forging design module, the magnitude of various allowances, draft angle, minimum web thickness, corner and fillet radius are determined and then geometry modification is performed. Finally, since the design rules and databases used in this system are based on parameters of the forging geometry, such as the trimmed forging plan area, forging weight, forging maxmum size, plausible estimates need to be made for these parameters. Therefore, in the re-design module, the design process is iterated until a satisfactory forging is obtained.

• 한국전자파학회논문지
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• 제18권4호
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• pp.423-429
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• 2007

위성 DMB용 중계기는 위성으로부터 수신된 2.304 MHz의 기준 신호를 이용하여 10 MHz의 클럭 신호를 재생하여 시스템 동기 신호로 사용한다. 본 논문에서는 기준 신호가 잡음에 의해 흔들리거나 끊기더라도 안정된 신호를 재생할 수 있는 클럭 재생 모듈을 제안하였다. 제안된 모듈은 기존 방식에 비해 저가로 구현이 가능하며, 정기적인 주파수 조정이 필요 없는 장점이 있다. 본 논문에서는 클럭 재생용 IC를 CPLD를 이용하여 구현하였고, lock time을 짧게 하면서 동시에 출력 주파수의 hold over 시간을 늘리기 위해 새로운 루프 필터를 적용하였다. 제작된 모듈은 출력 주파수의 안정도가 0.01 ppm 이내일 경우 hold over 시간이 11초, 출력 전력은 -0.66 dBm, 위상잡음은 100 Hz 오프셋에서 -113 dBc/Hz로 측정되었다.

• 대한수학회논문집
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• 제19권2호
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• pp.233-242
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• 2004

The aim of this note is to study properties of the generalized centroid of the semi-prime gamma rings. Main results are the following theorems: (1) Let M be a semi-prime $\Gamma$-ring and Q a quotient $\Gamma$-ring of M. If W is a non-zero submodule of the right (left) M-module Q, then $W\Gamma$W $\neq 0. Furthermore Q is a semi-prime $\Gamma$-ring. (2) Let M be a semi-prime $\Gamma$-ring and $C_{{Gamma}$ the generalized centroid of M. Then $C_{\Gamma}$ is a regular $\Gamma$-ring. (3) Let M be a semi-prime $\Gamma$-ring and $C_{\gamma}$ the extended centroid of M. If $C_{\gamma}$ is a $\Gamma$-field, then the $\Gamma$-ring M is a prime $\Gamma$-ring.

• 대한산업공학회지
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• 제24권4호
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• pp.613-625
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• 1998

This paper addresses a fundamental and theoretical model for the shape of a cucumber and its human-oriented proper definition of length and curvature in order to sort cucumbers electronically. In addition, we design a T-shaped array of sensors to minimize the number of sensors and the processing number of A/D(Analog/Digital) conversions, and we analyze regular patterns of a series of 1's and 0's which are converted from an A/D module. Finally we suggest an algorithm for measuring the length and curvature providing a rule from the regular patterns. The methodology suggested in this paper could be applied to electronical classification of some crops and fruits such as tomatoes, apples, and so on, and can be a basis for developing other sorting machines.

• ETRI Journal
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• 제31권3호
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• pp.327-329
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• 2009

In a network, broadcasting is the dissemination of a message from a source node holding a message to all the remaining nodes through a call. This letter proposes a one-to-all broadcasting algorithm in the Petersen-torus network PT(n, n) for the single-link-available and multiple-link-available models. A PT(n, n) is a regular network whose degree is 4 and number of nodes is $10n^2$, where the Petersen graph is set as a basic module, and the basic module is connected in the form of a torus. A broadcasting algorithm is developed using a divide-and-conquer technique, and the time complexity of the proposed algorithm approximates n+4, the diameter of PT(n, n), which is the lower bound of the time complexity of broadcasting.

• 전자공학회논문지C
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• 제35C권3호
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• pp.69-78
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• 1998

This paper presented a method of extracting algorithm for Edge Multiple-Valued Decision Diagrams(EMVDD), a new data structure, from Binary Decision Diagram(BDD) which is resently using in constructing the digital logic systems based on the graph theory. We discussed the function minimization method of the n-variables multiple-valued functions and showed that the algorithm had the regularity with module by which the same blocks were made concerning about the schematic property of the proposed algorithm. We showed the EMVDD of Full Adder by module construction and verified the proposed algorithm by examples. The proposed method has the visible, schematical and regular properties.

• 대한수학회보
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• 제56권2호
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• pp.471-477
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• 2019

Let (R, m) be a commutative Noetherian ring, I an ideal of R and M a non-zero finitely generated R-module. We show that if M and $H_0(I,M)$ are aCM R-modules and $I=(x_1,{\cdots},x_{n+1})$ such that $x_1,{\cdots},x_n$ is an M-regular sequence, then $H_i(I,M)$ is an aCM R-module for all i. Moreover, we prove that if R and $H_i(I,R)$ are aCM for all i, then R/(0 : I) is aCM. In addition, we prove that if R is aCM and $x_1,{\cdots},x_n$ is an aCM d-sequence, then depth $H_i(x_1,{\cdots},x_n;R){\geq}i-1$ for all i.

• Kyungpook Mathematical Journal
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• 제61권2호
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• pp.239-248
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• 2021

In this paper we study modules with the W F I⁺-extending property. We prove that if M satisfies the W F I⁺-extending, pseudo duo properties and M/(Soc M) has finite uniform dimension then M decompose into a direct sum of a semisimple submodule and a submodule of finite uniform dimension. In particular, if M satisfies the W F I⁺-extending, pseudo duo properties and ascending chain (respectively, descending chain) condition on essential submodules then M = M₁ ⊕ M₂ for some semisimple submodule M₁ and Noetherian (respectively, Artinian) submodule M₂. Moreover, we show that if M is a W F I-extending module with pseudo duo, C₂ and essential socle then the quotient ring of its endomorphism ring with Jacobson radical is a (von Neumann) regular ring. We provide several examples which illustrate our results.

• 전기학회논문지P
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• 제65권4호
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• pp.309-315
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• 2016

NCS is the nation-wide standard designed to standardize and systematize the capability(knowledge, technology and attitude) required for personnel to undertake their task in industrial site according to industry field and level of the task. In order to cope with rapidly changing labor market, individual has to be equipped with ability required for each relevant duty field. And company also requires worker to have basic working ability, professional knowledge or technical capability for relevant duty. Especially, the core competency, a fundamental element for all tasks, has been recognized as critical part not just in social level but also in company level. In that sense, the necessity of adding the core competence into regular education program has been vastly demanded. This study mainly deals with development of NCS-based learning module for information capability that most of industrial field want their employee to be equipped as basic skill. And, in particular, education achievement analysis for computer application capability, a subordinate capabilities of information capability, and its application method are mainly described.