• Korean Journal of Mathematics
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• 제20권4호
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• pp.423-431
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• 2012

There have been some study characterizing monoids by homological classification using the properties around projectivity, injectivity, or regularity of acts. In particular Kilp and Knauer([4]) have analyzed monoids over which all acts with one of the properties around projectivity or injectivity are regular. However Kilp and Knauer left over problems of characterization of monoids over which all regular right S-acts are (weakly) at, (weakly) injective or faithful. Among these open problems, Liu([3]) proved that all regular right S-acts are (weakly) at if and only if es is a von Neumann regular element of S for all $s{\in}S$ and $e^2=e{\in}T$, and that all regular right S-acts are faithful if and only if all right ideals eS, $e^2=e{\in}T$, are faithful. But it still remains an open question to characterize over which all regular right S-acts are weakly injective or injective. Hence the purpose of this study is to investigate the relations between regular right S-acts and weakly injective right S-acts, and then characterize the monoid over which all regular right S-acts are weakly injective.

• 대한수학회논문집
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• 제37권2호
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• pp.347-358
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• 2022

In this paper, we first introduce the notions of superfluous and coessential subacts. Then hollow and co-uniform S-acts are defined as the acts that all proper subacts are superfluous and coessential, respectively. Also it is indicated that the class of hollow S-acts is properly between two classes of indecomposable and locally cyclic S-acts. Moreover, using the notion of radical of an S-act as the intersection of all maximal subacts, the relations between hollow and local S-acts are investigated. Ultimately, the notion of a supplement of a subact is defined to characterize the union of hollow S-acts.

• Journal of applied mathematics & informatics
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• 제26권1_2호
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• pp.395-400
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• 2008

Although the properties of flatness and condition (E) for Sacts over a monoid S are incomparable, Liu([10]) showed that necessary and sufficient condition for a monoid S over which all left S-acts that satisfy condition (E) are flat is the regularity of S. But the problem of describing a monoid over which all cyclic flat left S-acts satisfy condition (E) is still open. Thus the purpose of this paper is to characterize monoids over which all cyclic flat right S-acts satisfy condition (E).

• 교육시설
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• 제13권4호
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• pp.31-42
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• 2006

This study is about an analysis of the relation between the degree of cognition of student's acts within limits when coping with several types of disaster and the degree of cognition of damage by disasters in the method of multiple regression analysis. The dependent variable is the degree of cognition of student's acts within limits and the independent variable is the degree of cognition of damage by disasters such as heavy snow, typhoon, heavy rain, heat, and yellow sand. A survey of graduates of metropolitan area high-schools has found that there are no difference between girls and boys of the degree of cognition of student's acts within limits when coping with disasters. This study finds that the independent variable, which are playgrounds, animals and plants, streets and roads, altitude and incline, gives positive effect to the degree of cognition of student's acts within limits when coping with typhoon or heavy rain in order. The study also finds that the degree of cognition of student's acts within limits when coping with heavy snow is affected positively by streets and roads, playgrounds, altitude and incline in order. It also shows that there are factors that has an effect to the degree of cognition of student's acts within limits when coping with yellow sand and heat. This study proposes suggestions to facility plans based on these facts discovered.

• Asian Journal of Innovation and Policy
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• 제10권3호
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• pp.355-379
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• 2021

This study examined the evolution of S&T Basic Acts in Korea from the Science and Technology Promotion Act (1967) through the Special Act on STI (1997) to the Framework Act on Science and Technology (2001) in the following aspects: 1) comprehensive plans, 2) coordination mechanisms for S&T policies, 3) enforcement of R&D programs and performance diffusion, 4) promotion of human resources, 5) and S&T investment and budgeting. Before the Framework Act on S&T was enacted in 2001, critical issues were found in establishing S&T master plans, promotion of R&D programs, comprehensive coordination mechanisms, and R&D budgeting. The three Basic Acts have expanded the scope of regulation over time to cover the entire cycle of the S&T process. They concern a wide range of issues, including creating a basis for scientific and technological development, S&T promotion, disseminating and commercializing research outcomes, and preventing adverse effects from science and technology. The content of the Basic Acts has evolved in response to changes in the political, economic, and social environment of Korean industry during the past five decades.

• 호남수학학술지
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• 제35권3호
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• pp.381-388
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• 2013

In this article we introduce the notion of fully idempotent acts and by this we give a characterization of commutative monoids over which all cyclic right acts are injective.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제5권4호
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• pp.498-506
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• 1999

본 논문에서는 ATM 통신프로토콜을 위한 자동시험시스템인 ACTS(ATM Conformance Test System)의 개발과 적용을 소개한다. ACTS는 ITU-T 또는 ATM Forum의 ATM 사용자-망 접속표준을 준용하는 ATM 단말과 망장비의 프로토콜적합성을 확인하는데 사용된다. 본 논문에서는 ACTS 개발에 사용된 방법을 소개한 뒤, ACTS를 실제 ATM 단말과 장비에 적용한 사례들을 소개한다. ACTS의 적용을 통하여 시험대상 장비들이 지닌 프로토콜구현상의 문제점을 파악하였고, 문제에 대한 원인분석을 수행하였다. 또한 이러한 문제점들이 상호운용에 미치는 장애를 예측함으로써, ACTS를 상호운용하는 ATM 장비를 확보하기 위한 유용한 도구로 사용할 수 있음을 보인다.Abstract This paper presents development and application of ACTS(ATM Conformance Test System), an automated test system for ATM protocols. ACTS is a test system that checks conformance of ATM terminal and network equipment implementing either ITU-T or ATM Forum user-network interface. This paper, after presenting the methodology and process used for developing ACTS, conducts case studies of its applications to real ATM equipment. By applying ACTS, we were able to detect numerous problems in protocol implementations of ATM equipment and analyse causes of the problems, thereby demonstrating the efficacy of ACTS as an efficient automated testing tool. Furthermore, by predicting the potential effects of the problems on interoperability, we show how ACTS can be used as a useful tool for ensuring interoperable ATM equipment.

• 한국항공운항학회지
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• 제25권4호
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• pp.161-169
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• 2017

The Human Factors Analysis and Classification System (HFACS) is a general human error framework originally developed and tested within the U.S. military as a tool for investigating and analyzing the human causes of aviation accidents. Based upon Reason's (1990) model of latent and active failures, HFACS addresses human error at all levels of the system, including the condition of aircrew and organizational factors. As a result, this study aims to examine the influence between the latent conditions based on HFACS. This study seeks to verify the factors of "Organizational Influence" effecting the "Precondition for Unsafe Acts" of HFACS. The results of empirical analysis demonstrated that the organizational influence had a positive influence on precondition for unsafe act, especially the "Organizational Climate" of organizational influence had even greater influence on precondition for unsafe acts.

• 대한인간공학회지
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• 제25권4호
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• pp.137-144
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• 2006

The goal of this study is to find out correlation between Driver's Unsafe acts(errors and violations) and Personality types. The experiment was performed on 180 subjects, men and women between 20's and 60's having experience in driving for 6 months at least. Personality types of the subjects were classified by MBTI(Myers-Briggs Type Indicator) GS type and Driver's unsafe acts were measured by KDBQ(Korean Driver Behavior Questionnaire) based on Reason's DBQ(Driver Behavior Questionnaire). The result of experiment showed several facts about the relation. The first is that the drivers of P (Perceiving) type commit more violations and slips than drivers of J(Judging) type. The second is that in the comparison among attitude indexes(EP, EJ, IP, IJ) the drivers of EP(Extroversions - Perceiving) commit more violations than other type drivers. Finally, only men of P(Perceiving) type commits more violations than men of J(Judging). Based on these facts, it is possible to use Personality types as a device to prevent unsafe acts in various fields for driver selection and accident prevention training classified by Personality types etc.

• 미국학
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• 제44권2호
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• pp.97-129
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• 2021

In The White Card (2019), Claudia Rankine dramatically interrogates whiteness's persistent, reflexive habit of trying to preserve a state of innocence, expressing her vision of how this tendency blinds white liberal subjectivity to the structural reality of institutionalized racism in America. Rankine's exposure of the invisibility to which people of color are usually consigned by American whiteness is inseparable from her critical interrogation of how the hypervisibility of victims of racial violence provides white liberal subjectivity opportunities to intervene and feel good about itself. What Rankine enacts in the play is a process of repetition and revision, signifyin(g) on racial violence and its history; acts of racial violence continue to accrete, and her act of signifyin(g) on the countless acts of racial violence in America conveys the understanding that this text cannot be rewritten if white America continues to attend solely to individual, ostensibly isolated, acts of racial injustice.