• Korean Journal of Logic
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• v.16 no.1
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• pp.45-59
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• 2013

In his book Worlds and Individuals: Possible and Otherwise, Takashi Yagisawa Yagisawa argues that his own theory is better than Lewis's theory by showing that his own theory can deal with important objections to modal realism more successfully than Lewis's. In particular, Yagisawa claims that by adopting modal tenses, he can respond to many important objections to modal realism in a uniform way. In this paper, I argue that Lewis can also successfully respond to Peacocke's objection in an exactly parallel way to Yagisawa's by distinguishing existence at the actual world from existence at other possible worlds and that Yagisawa's response to van Inwagen's objection does not succeed. I conclude that Yagisawa fails to show that his own theory is better than Lewis's.

• Korean Journal of Logic
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• v.20 no.1
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• pp.113-141
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• 2017

The standard definition of an instantaneous temporal part cannot properly deal with cases involving time travel. This paper provides a new definition of an instantaneous temporal part by appealing to David Lewis's distinction between external time and personal time. The new definition avoids the problems because it does not allow more than one instantaneous temporal part of an object at each moment of its personal time. We argue that this new definition, combined with our new perdurantist semantic thesis, deals with cases of time travel successfully.

• Lingua Humanitatis
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• v.2 no.2
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• pp.301-319
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• 2002

In a recent paper, I have proposed an analysis concerning propositions and 'that'-clauses as a solution to Kripke's puzzle and other similar puzzles, which I now call 'the Indefinite Description Analysis of Belief Ascription Sentences.' I have listed some of the major advantages of this analysis besides its merit as a solution to the puzzles: it is amenable to the direct-reference theory of proper names; it does not nevertheless need to introduce Russellian (singular) propositions or any other new entities. David Lewis has constructed an interesting argument to refute this analysis. His argument seems to show that my analysis has an unwelcome consequence: if someone believes any proposition, then he or she should, ipso facto, believe any necessary (mathematical or logical) proposition (such as the proposition that 1 succeeds 0). In this paper, I argue that Lewis's argument does not pose a real threat to my analysis. All his argument shows is that we should not accept the assumption called 'the equivalence thesis': if two sentences are equivalent, then they express the same proposition. I argue that this thesis is already in trouble for independent reasons. Especially, I argue that if we accept the equivalence thesis then, even without my analysis, we can derive a sentence like 'Fred believes that 1 succeeds 0 and snow is white' from a sentence like 'Fred believes that snow is white.' The consequence mentioned above is not worse than this consequence.

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.60-64
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• 2006

Propagation rates ($U_{edge}$) of various premixed, twin edge-flames were measured as a function of global strain rate ($\sigma$), mixture strength, and Lewis number (Le). Using a counterflow slot-jet burner with electrical heaters at each end, both advancing (positive $U_{edge}$) and retreating (negative $U_{edge}$) edge-flames can be studied as they propagate along the long dimension of the burner. Experimental results are presented for premixed methane/air twin flames in terms of the effects of $\sigma$ on $U_{edge}$. Both low-$\sigma$ and high-$\sigma$ extinction limits were discovered for all mixtures tested. As a result, the domain of edge-flame stability was obtained in terms of heat loss factor and normalized flame thickness, and comparison with the numerical result of other researchers was also made. For low ($CH_4/O_2/CO_2$) and high ($C_3H_8$/air) Lewis number cases, propagation rates clearly show a strong dependence on Le.

• Journal of the Korean Society of Combustion
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• v.14 no.1
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• pp.25-30
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• 2009

Propagation rates ($U_{edge}$) of various premixed, twin edge-flames were measured as a function of global strain rate ($\sigma$), mixture strength, and Lewis number (Le). Using a counterflow slot-jet burner with electrical heaters at each end, both advancing (positive $U_{edge}$) and retreating (negative $U_{edge}$) edge-flames can be studied as they propagate along the long dimension of the burner. Experimental results are presented for premixed methane/air twin flames in terms of the effects of $\sigma$ on $U_{edge}$. Both low-$\sigma$ and high-$\sigma$ extinction limits were discovered for all mixtures tested. As a result, the domain of edge-flame stability was obtained in terms of heat loss factor and normalized flame thickness, and comparison with the numerical result of other researchers was also made. For low ($CH_4/O_2/CO_2$) and high ($C_{3}H_{8}$/air) Lewis number cases, propagation rates clearly show a strong dependence on Le.

• Journal of Trauma and Injury
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• v.30 no.2
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• pp.25-32
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• 2017

Purpose: The use of computed tomography (CT) to evaluate acute abdominal complaints has increased over the past two decades. We investigated how the clinical practice of patients with intestinal perforation has changed with the increasing use of abdominal CT in the emergency department (ED). Methods: We compared ED arrival to CT time, ED arrival to surgical consultation time, and ED arrival to operation time according to the method of diagnosis from 2003-2004 and 2013-2014. Results: In patients with gastrointestinal perforation, time from ED arrival to CT was shorter ($111.4{\pm}66.2min$ vs. $199.0{\pm}97.5min$, p=0.001) but time to surgical consultation was longer ($135.1{\pm}78.8$ vs. $77.9{\pm}123.7$, p=0.006) in 2013-2014 than in 2003-2004. There was no statistically significant difference in time to operation for perforation confirmed either by plain film or CT between the two time periods. There was no statistically significant difference in length of hospital or ICU stay or mortality between the two groups. Conclusion: With the increasing use of abdominal CT in ED, ED arrival to CT time has decreased and ED arrival to surgical consultation time has increased in gastrointestinal perforation. These changes of clinical performance do not delay ED arrival to operation time or adversely influence patient outcome.

• Korean Journal of Logic
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• v.13 no.1
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• pp.21-52
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• 2010

What van Fraassen calls 'Reflection Principle' is claimed to meet several counterexamples, one of which stands out in the form of the Sleeping Beauty problem. Adam Elga argues that what he believes is the correct answer to the Sleeping Beauty problem shows that Reflection is subject to counterexamples. David Lewis proposes a different answer which preserves Reflection intact. Recently, Nick Bostrom presents a hybrid view which is supposed to allow us to keep Reflection. In proposing his hybrid view Bostrom criticizes both Elga and Lewis while taking some 'good' parts from each. He claims that Elga's view is not entirely acceptable because it presupposes the 'Self-Indication Assumption'. I shall claim, however, that Elga could avoid Bostrom's criticisms by introducing Bostrom's notion of agent-part. I believe that several probability-related puzzles including the Sleeping Beauty problem indicate a promising view concerning the way we should regard our future selves' opinions. According to this view, whether one takes the outsider stance or insider stance makes a difference in an important way that one and the same proposition is associated with different degrees of belief by one agent.

• Korean Journal of Logic
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• v.8 no.2
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• pp.109-141
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• 2005

In this paper, I raise an objection to "sensitivism" about "know", according to which knowledge ascription is sensitive to contexts of utterance or subjects. While Peter Unger once proposed insensitivism about "know" in terms of insensitivism with respect to absolute terms, David Lewis provided sensitivism about "know" in terms of sensitivism with respect to absolute terms, on the common ground that "know" belongs to a class of absolute terms. On the one hand, I object to Unger-style insensitivism about 'know,' for, I claim, we have reason to opt for sensitivism rather than insensitivism with respect to absolute terms in virtue of the maxim that I call "semantic razor." On the other hand, I also object to sensitivist approaches to "know," for, on reflection, there is such a deep difference between "know" and absolute terms (or, sensitive terms altogether) that "know" cannot be taken to sensitive to contexts as opposed to absolute terms (or, sensitive terms altogether). These claims jointly indicate that "know" should be thought of as an insensitive term even though sensitivism has enjoyed wide acceptance in many other cases.

• 한국연소학회:학술대회논문집
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• 2006.04a
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• pp.7-12
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• 2006

The propagation rates ($U_{edge}$) of various premixed edge-flames were measured as a function of global strain rate (${ \sigma}$), mixture strength, and Lewis number (Le). Using a counterflow slot-jet burner with electrical heaters at each end, both advancing (positive $U_{edge}$) and retreating (negative $U_{edge}$) edges can be studied as they propagate along the long dimension of the burner. Preliminary results are presented for single and twin premixed hydrocarbon edge-flames in terms of the effects on $U_{edge}$. A low-${\sigma}$ extinction limit has been discovered for all mixtures tested but further analysis is necessary for full characterization since sufficiently $high-{\sigma}$ leads to an apparent stability limit. Propagation rates clearly show a strong dependence on Le. Future work will focus on completing the premixed hydrocarbon edge-flame analysis and include investigations into non-premixed edge-flames and edge-flames composed of fuels such as hydrogen ($H_2$) with significantly lower Le.

• Journal of Microbiology and Biotechnology
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• v.21 no.4
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• pp.359-365
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• 2011

Cyanobacterial strains of the genus Spirulina have recently been identified as an excellent source of sulfolipids, some of which possess anti-HIV properties. Thus, to investigate the distribution of sufolipid biosynthesis pathways in Spirulina, a genetic screening/phylogentic study was performed. Five different strains of Spirulina [Spirulina (Jiangmen), Spirulina sp., S. platensis, S. maxima, and Spirulina seawater] sourced from different locations were initially classified via 16S rDNA sequencing, and then screened for the presence of the sulfolipid biosynthesis genes sqdB and sqdX via a PCR. To assess the suitability of these strains for human consumption and safe therapeutic use, the strains were also screened for the presence of genes encoding nonribosomal peptide synthases (NRPSs) and polyketide synthases (PKSs), which are often associated with toxin pathways in cyanobacteria. The results of the 16S rDNA analysis and phylogenetic study indicated that Spirulina sp. is closely related to Halospirulina, whereas the other four Spirulina strains are closely related to Arthrospira. Homologs of sqdB and sqdX were identified in Spirulina (Jiangmen), Spirulina sp., S. platensis, and the Spirulina seawater. None of the Spirulina strains screened in this study tested positive for NRPS or PKS genes, suggesting that these strains do not produce NRP or PK toxins.