• Korean Journal of Logic
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• v.6 no.1
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• pp.1-18
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• 2003

1989년 네일버프(B. Nalebuff)에 의해서 두 봉투의 역설이 제시된 이래 많은 철학자들이 이 역설에 많은 논의가 있었데 이 역설에 대한 논의를 다시 촉발시킨 글은 1997년의 잭슨(F. Jackson)과 멘지스(P. Menzies)와 오피(G. Oppy)가 발표한 논문이다. 이 글은 잭슨 등의 논문에서 제시된 두 봉투의 역설에 대한 설명을 토대로 두 봉투의 역설이 생긴다고 생각하는 이유는 무엇이고, 구체적으로 어떤 경우에 역설이 생길 수 있는지를 살펴본다. 그리하여 필자는 다음 두 가지를 주장할 것이다 첫째 두 봉투의 역설이라고 불리는 것은 봉투에 들어있는 금액이 무한하고 동시에 그 금액의 평균값이 무한한 경우만 발생할 수 있을 뿐이고, 이는 내가 선택한 봉투 안의 기대값을 실제로 계산할 수 없는 경우이다. 둘째로 기대값이 실제로 계산될 수 있는 그 외의 경우, 역설은 발생하지 않으며 역설이 발생한다고 생각하는 것은 자신의 봉투 안의 금액을 고정적인 것으로 상대방의 금액을 가변적인 것으로 해석하는 잘못으로부터 기인하는 것이다. 요컨대 기대값이 계산될 수 있는 일반적인 경우 두 봉투의 역설이 생긴다고 생각하는 것은 잘못이고 그 경우 역설은 발생하지 않는다는 것을 논증할 것이다.

• Journal of the Korean Society of Systems Engineering
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• v.8 no.1
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• pp.29-39
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• 2012

The conventional systems engineering has been performed mainly based on documentation artifacts. Although the Document-Based Systems Engineering has played a very important role in developing and deploying systems, it is difficult for systems engineers to build, to clarify, and to reuse the operational, functional and physical views of the System of Interest (SOI) efficiently. An information-age approach to this problem is the Model-Based Systems Engineering which has been emerging as a very productive solution for stakeholders to define, and understand the desired systems easily, to communicate and collaborate efficiently among each other, and also to verify and validate the systems solutions effectively. This paper proposes a set of MBSE process, methods, and models for use during the systems analysis and design phase of the naval combat system development. An example application of the proposed approach was exercised and a set of artifacts was generated for an export combat system project to demonstrate its effectiveness.

• Journal of the Korean Society of Systems Engineering
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• v.6 no.2
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• pp.21-27
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• 2010

As system is larger, and technology evolves, the system gets complicated due to its integration and heterogeneity of system components. To address its complexity and to accomplish efficient system development, various methodologies have been developed. MBSE using Models and tools is one of methodologies. MBSE methodologies and its products are differently applied according to the organization and project. It is proper that unique methodology is applied in a development of single system. But what if a variety of methodologies are applied in the same domain or SoS development, it will cause a confusion of communication and waste of engineering efforts. As a way to resolve this, it can be considered that MBSE using architecture framework that clearly define products. In other words, by taking advantage of that an architecture framework provides the type, representation and meta-model of products, the reusability and universality of MBSE products can be improved.

• Korean Journal of Logic
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• v.13 no.2
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• pp.61-82
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• 2010

The argument from ignorance that knowledge conclusion is derived from ignorance premises is claimed to be fallacious by many logicians such as I. Copi. According to them, some arguments from ignorance which seem to be acceptable are not really the arguments from ignorance. They say that such arguments have implicitly conditional knowledge premise. Against them, I argue that every argument from ignorance can be interpreted as having a hidden conditional premise, and that every argument from ignorance is not fallacious. I propose the criterion to judge which argument from ignorance is fallacious and which is persuasive. In particular, I argue that social contexts play a crucial role to judge whether a practical argument is fallacious or not.

• Korean Journal of Logic
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• v.17 no.3
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• pp.373-399
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• 2014

This paper deals with the question whether the metaphysical dialetheism is a persuasive view or not. That is, the purpose of this paper is to criticize the metaphysical dialetheism by answering three questions, whether the dialetheism is compatible with the correspondence theory of truth, whether there is an observable contradiction, finally what the status of LNC is. In conclusion, it is argued that dialetheism is incompatible with the correspondence theory of truth, because it results in trivialism to suppose that two views are compatible. It is also claimed that LNC should be understood as the principle of exclusion which constrains the structure of the world and that the real world is consistent. Therefore, there is no observable contradiction in the world and the metaphysical dialetheism is not persuasive.

• Korean Journal of Logic
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• v.16 no.3
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• pp.381-406
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• 2013

This paper deals with the question whether the para-completeness theory of Kripkian style can avoid the revenge problem. According to the para-completeness theory, there are some sentences that are neither true nor false. And the liar sentence is the exemplar of such sentences. But the para-completeness theory has been criticised to give rise to the revenge problem, since Kripke suggested his theory. Maudlin argues that he can construct the para-completeness theory which avoids the problem by appealing to his foundationalist semantics. The aim of this paper shows that the para-completeness theory, including Maudlin's, cannot avoid the problem. Furthermore, it is argued that Maudlin's view is ad hoc suggestion just to avoid the problem.

• Korean Journal of Logic
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• v.17 no.2
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• pp.233-253
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• 2014

The Pinocchio paradox that Eldridge-Smith suggested is a version of the semantic paradox. But it is unique in the sense that this paradox does not contain a semantic predicate. Tarski's solution which appeals to the hierarchy of language and Kripke's para-completeness which accepts the third truth value cannot solve the Pinocchio paradox. This paper argues that Eldridge-Smith's trial to criticize semantical dialetheism is not successful and that the paradox implies the rule of the truth predicate is inconsistent. That is, the proper diagnosis to this paradox is that the Pinocchio principle should be considered to be potentially inconsistent, which suggests that semantic paradoxes such as the liar paradox arise because the rule of the truth-predicate is inconsistent. The Pinocchio paradox teaches us that consistent view of truth cannot be successful to solve the semantic paradoxes and that we should accept the inconsistent view of truth.

• Korean Journal of Logic
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• v.1
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• pp.65-93
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• 1997

거짓말쟁이 역설에 대한 전통적인 설명은 다음 두 가지로 주어진다. 역설을 일으키는 거짓말쟁이 문장이 자기지시적이기 때문에 역설이 발생하므로 자기지시적 문장을 금함으로써 그 역설을 피할 수 있다는 것이 첫 번째이고, 둘째는 모든 문장을 참이나 거짓이라고 주장하는 진리값에 대한 배중률(principle of bivalence)에 집착하기 때문에 그 역설이 발생한다고 생각하고 제3의 진리값을 갖는 문장이 있음을 인정해야 한다는 것이다. 이러한 전통적인 설명과 달리 진리 개념을 비일관적인 개념으로 보고 진리 술어와 그 외의 술어의 용법상의 차이를 설명함으로써 거짓말쟁이 역설에 대한 새로운 설명을 시도하고자 하는 것이 굽타의 "진리 수정론"이다. 굽타의 진리 수정론에 따르면, 진리 술어 외의 술어들은 그 외연이 고정적으로 산출되고 그 과정은 적용 규칙(rule of application)에 의해서 설명되지만 진리 술어는 순환적 정의처럼 고정된 외연을 만들어내지 못하고 단지 가설적 외연만 만들어 낼 뿐이다. 이렇게 진리술어의 가정적 외연을 산출해내는 과정은 수정규칙(rule of revision)에 의해서 설명된다. 요컨대 진리 수정론은 순환적 개념도 의미를 가질 수 있음을 보여주는 의미론적 구조틀이 있다는 것과 진리개념이 바로 그러한 의미구조틀에 의해서 의미를 갖는 순환적 개념이라는 것이다. 그리고 굽타는 그러한 의미구조 틀을 일정한 규칙을 갖는 함수로 설명하려고 시도한다. 즉 진리개념을 일관적인 것으로 보고 거짓말쟁이 역설을 해결해야 할 병리적 현상으로 보는 진리의 일관성론과 달리 굽타의 진리 수정론은 진리술어 자체가 비일관적이기 때문에 거짓말쟁이 역설은 그 술어의 속성상 자연스러운 것이지 피해야 만할 병리적 현상이 아니라고 주장한다. 필자는 의미론적 역설에 대한 여러 가지 설명 중에서 진리 수정론이 가장 설득력 있는 것으로 인정하고 그에 대한 가능한 반론을 검토하고 그에 대한 답변을 시도했다. 또한 진리 수정론을 통해서 거짓말쟁이 역설을 설명하고 -해결하려는 것이 아니라- 나아가서 진리 개념에 대한 이해를 제공해보려고 시도했다.

• Korean Journal of Logic
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• v.12 no.2
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• pp.31-58
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• 2009

This paper defends Stalnaker's theory of indicative conditionals. His theory consists of selection functions and pragmatic constraints. The selection function takes a certain possible world(W) and a proposition(A) to yield a possilble world that is similar to W and in which A is true. And the pragmatic constraints plays role to make selection functions apply just to indicative conditionals. According to Stalnaker, as indicative conditionals has strong truth-value, uncontested principle always holds but passage principle does not always hold. However, his theory can explain why passage principle sometimes holds by means of pragmatic constraints. Also, this paper argues that Stalnaker's theory is the most acceptable one among others, by replying to criticisms suggested by Adamsians and the problem raised by Gibbard and other criticisms.

• Korean journal of applied entomology
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• v.48 no.3
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• pp.377-383
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• 2009

This study was conducted to investigate the total phenol contents, antioxidative activities and antibacterial activities of twenty species of entomopathogenic fungi. The total phenol content was highest in Aspergillus flavus ($553.0{\pm}52.15{\mu}g/g$) and A. parasiticus ($529.9{\pm}60.10{\mu}g/g$). On the other hand those in other strains were within the range of $26.6{\sim}121.9{\mu}g/g$. The antioxdative activity was shown in the most of strains and the highest DPPH (1, 1-diphenyl-2-picrylhydrazyl) radical scavenging activity was observed in A. flavus ($90.9{\pm}2.90%$) and A. parasiticus ($77.9{\pm}4.13%$). This result indicated that the antioxidative activities were very correlated with the total phenol contents. The antibacterial activitiy was found in the every tested pathogenic bacteria. Especially, the antibacterial activity was strongest against Listeria monocytogenes and Escherchia coli.