• Title/Summary/Keyword: speaking

Search Result 1,200, Processing Time 0.024 seconds

The Early Wittgenstein on the Theory of Types (전기 비트겐슈타인과 유형 이론)

  • Park, Jeong-il
    • Korean Journal of Logic
    • /
    • v.21 no.1
    • /
    • pp.1-37
    • /
    • 2018
  • As is well known, Wittgenstein criticizes Russell's theory of types explicitly in the Tractatus. What, then, is the point of Wittgenstein's criticism of Russell's theory of types? In order to answer this question I will consider the theory of types on its philosophical aspect and its logical aspect. Roughly speaking, in the Tractatus Wittgenstein's logical syntax is the alternative of Russell's theory of types. Logical syntax is the sign rules, in particular, formation rules of notation of the Tractatus. Wittgenstein's distinction of saying-showing is the most fundamental ground of logical syntax. Wittgenstein makes a step forward with his criticism of Russell's theory of types to the view that logical grammar is arbitrary and a priori. His criticism of Russell's theory of types is after all the challenge against Frege-Russell's conception of logic. Logic is not concerned with general truth or features of the world. Tautologies which consist of logic say nothing.

Simulated Study on the Effects of Substrate Thickness and Minority-Carrier Lifetime in Back Contact and Back Junction Si Solar Cells

  • Choe, Kwang Su
    • Korean Journal of Materials Research
    • /
    • v.27 no.2
    • /
    • pp.107-112
    • /
    • 2017
  • The BCBJ (Back Contact and Back Junction) or back-lit solar cell design eliminates shading loss by placing the pn junction and metal electrode contacts all on one side that faces away from the sun. However, as the electron-hole generation sites now are located very far from the pn junction, loss by minority-carrier recombination can be a significant issue. Utilizing Medici, a 2-dimensional semiconductor device simulation tool, the interdependency between the substrate thickness and the minority-carrier recombination lifetime was studied in terms of how these factors affect the solar cell power output. Qualitatively speaking, the results indicate that a very high quality substrate with a long recombination lifetime is needed to maintain the maximum power generation. The quantitative value of the recombination lifetime of minority-carriers, i.e., electrons in p-type substrates, required in the BCBJ cell is about one order of magnitude longer than that in the front-lit cell, i.e., $5{\times}10^{-4}sec$ vs. $5{\times}10^{-5}sec$. Regardless of substrate thickness up to $150{\mu}m$, the power output in the BCBJ cell stays at nearly the maximum value of about $1.8{\times}10^{-2}W{\cdot}cm^{-2}$, or $18mW{\cdot}cm^{-2}$, as long as the recombination lifetime is $5{\times}10^{-4}s$ or longer. The output power, however, declines steeply to as low as $10mW{\cdot}cm^{-2}$ when the recombination lifetime becomes significantly shorter than $5{\times}10^{-4}sec$. Substrate thinning is found to be not as effective as in the front-lit case in stemming the decline in the output power. In view of these results, for BCBJ applications, the substrate needs to be only mono-crystalline Si of very high quality. This bars the use of poly-crystalline Si, which is gaining wider acceptance in standard front-lit solar cells.

A Study on the Failure Factors of Popular Use of International Domain Names (IDNs): Focusing on the International Standardization Process (다국어도메인의 대중화 실패 요인 탐색: 국제표준화 과정 분석을 통하여)

  • Lee, Jin-Rang
    • Informatization Policy
    • /
    • v.23 no.3
    • /
    • pp.43-63
    • /
    • 2016
  • This research analyzes the international standardization process by observing the international communication sources in order to understand the reason of its current poor use. Using the 'organizing theory' frame, we observe the initial discourse on the need of internationalized domain names in ICANN and the process of negotiation for technical choice of layers. Lastly, we take Korean domain names as a case study in order to understand the conflict and the cooperation of different stakeholders. We summarize the factors of failure of IDN as follows. First, the need of IDN in the beginning was raised around non-English speaking countries, in Asia and Middle East, with the discourse on 'digital divide solution and cultural value' ICANN rather pursues the 'technical stability of Internet Infrastructure', which made its standardization take as long as 10 years. As a result, a variety of standards and services are proposed in the marketplace, which engendered inefficient competition and domain name-related disputes such as cybersquatting, technical instability and confusion of users. In addition, the government agencies fail to present the appropriate policies adjusting multiple interests of different stakeholders.

An Analysis of the Contents and Make-up of the Page in a News Story of the Internet Newspaper -focusing on Naver, Daum, Nate, Yahoo- (인터넷신문의 뉴스기사 페이지 구성과 콘텐츠에 대한 분석 -네이버, 다음, 네이트, 야후를 중심으로-)

  • Park, Kwang-Soon
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.3
    • /
    • pp.1345-1354
    • /
    • 2014
  • This paper has analyzed how the format of the text page and the contents of space surrounding the text in the news stories of the portal sites are made-up. The result of analysis showed that the formats of the text page in Naver news story were more intricate than those of Daum, Nate and Yahoo. Also, Naver was higher in the number of advertising, the type of advertising, the entertainment contents, and various types of contents than other three portals. Especially, the percentage of new story related to entertainers was the highest. It was the portal site Daum that advertised the news story most of all in its text page. In contrast, it was portal site Yahoo that inserted the advertisements least of all. But from the whole sides, it was found that the formats and contents of the text page of the news story in these three portal sites have similarly been made-up. Consequently speaking, for the serviceability of use in news story, it can be evaluated that the news service method in portal sites is higher than that in press dot coms.

An Empirical Study of Relationship between Object-oriented Metrics and Maintainability (객체지향 메트릭과 유지보수성과의 관계에 대한 실험적 연구)

  • Jung Woo-Seong;Chae Heung-Seok
    • The KIPS Transactions:PartD
    • /
    • v.13D no.2 s.105
    • /
    • pp.241-250
    • /
    • 2006
  • Software maintenance is an important and very expensive activity in software life cycle. To estimate the maintainability cost of software, many software metrics have been proposed. This paper presents the result of an experimental study to explore the relationship between maintainability and some software metrics. LCOM, RFC, DAC, and LOC are employed as metrics and time really spent for maintenance activity has been collected. In the experimental study, we have found that for some systems, the existing metrics may not be an indicator to maintenance effort, which is not consistent with our general knowledge on the relationship between them. Specifically speaking, we recognized that there should be more empirical study on the relationship between metrics and maintainability of softwares which have been developed using recent technologies such as software architecture and design pattern.

A Novel CFR Algorithm using Histogram-based Code Domain Compensation Process for WCDMA Basestation (히스토그램 기반 코드 영역 보상 기법을 적용한 W-CDMA 기지국용 CFR 알고리즘)

  • Chang, Hyung-Min;Lee, Won-Cheol
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.12C
    • /
    • pp.1175-1187
    • /
    • 2007
  • This paper proposes a novel crest factor reduction (CFR) algorithm to be deployed on WCDMA basestation. Generally speaking, it is well described that the reduction of peak-to-average ratio (PAR) yields the possibility of using low cost power amplifier such that the basesation becomes economic However, the simple reduction of PAR could degrade the signal quality measured by either peak code domain error (PCDE) or error vector measurement (EVM), and the level of channel interference constrained by adjacent channel leakage ratio (ACLR). Regarding these imperfections, this paper introduces an effective CFR algorithm in which the function of filter-dependent CFR (FDCFR) incorporated with the histogram-based waterfilling code domain compensation (HBWCDC) carries out. To verify the performance of the proposed CFR technique, substantial simulations including comparative works are conducted with obeying W-CDMA basestation verification specification. To exploit the superiority, the performance of the proposed method is tentatively compared with that associated to the simple memoryless clipping method and the memory-required filter-dependent clipping method.

A Study on the Borided Stsucture of Cast Iron (주철(鑄鐵)의 침붕조직(浸硼組織)에 관(關)한 연구(硏究))

  • Kim, H.S.;Ra, H.Y.
    • Journal of Korea Foundry Society
    • /
    • v.2 no.3
    • /
    • pp.2-15
    • /
    • 1982
  • In this study, the influenced of graphite shape on the boriding of cast iron and boride structure was investigated. Gray cast iron, ferritic and pearlitic ductile cast iron were borided at 750,850,900 and $950^{\circ}C$ for 1,3 and 5 hours by powder pack method with the mixture of $B_4C_9\;Na_2B_4O_7$, $KBF_4$ and Shc. The boride layer was consisted of FeB(little), $Fe_2B$ (main) and graphite. Some possibility of the existence of unknown Fe-B-C compound in the boride layer was suggested. And precipitates in the diffusion zone was $Fe_3(B,C)$. The concentration of Si and precipitation of $Fe_3(B,C)$ in the ${\alpha}$ layer raised the hardness of this Zone. The depth and hardness of boride layer increased with the increase of treating temperature and tim. But high temperature (over $950^{\circ}C)$ caused pore at graphite position and long treating time (5hrs) sometimes caused formation of graphite layer beneath the boride layer. So, for the practical application of borided cast iron, treating in short time and at low temperature was recommended. And for ductile cast iron, ferritizing or pearlitizing heat treatment was seemmed to be possible at the same time with boriding. The graphite in the boride layer was deeply concerned with the qualitx and characteristics of the boride layer. And it greatly influenced on the shape of the boride phase, structure of the boride layer. Generally speaking, the existance of graphite restrained the growth of the boride phase. But the boundary between the gsaphite and the matrix acted as the shortcut of boron diffusion. So, for gray cast iron, the graphite layed length-wise led the formation of boride layer.

  • PDF

국내 화력발전산업의 연료의 효율적 배분과 CO2 저검규모 추정

  • Lee, Myeong-Heon
    • Environmental and Resource Economics Review
    • /
    • v.21 no.1
    • /
    • pp.3-25
    • /
    • 2012
  • Generally speaking, firms, faced with a regulatory environment, are likely to use more or less inputs than optimal level due to allocative inefficiency of inputs. This paper, first, tests allocative efficiency of fuel inputs and calculates the divergence between the actual and optimal levels of each fuel input conditional on the optimal level of capital stock in Korean thermal power industry. Then, given that each fuel is efficiently allocated. potential reduction of $CO_2$ is estimated over the period 1987~2008. The null hypothesis of allocative efficiency with respect to all fuels is rejected, indicating that thermal power plants fail to attain cost minimization subject do market prices. Allocative efficiency between each pair of fuels is also tested; efficient uses of fuels relative to each other are all rejected. Empirical results indicate that coal and gas are used more and oil is used less than optimal level. On average, more than 10 million tons of $CO_2$ per year could be reduced by achieving allocative efficiency of fuels.

  • PDF

Perspectives on Learning English of Korean·Chinese·Japanese Students in an English Department in Korea (국내 영어학과 수업 내 한·중·일 학생들의 영어 학습에 관한 인식)

  • Lee, Younghwa;Kim, Seon Jae
    • The Journal of the Korea Contents Association
    • /
    • v.15 no.12
    • /
    • pp.650-659
    • /
    • 2015
  • This study reports on the perspectives of Korean Chinese Japanese students (KS CS JS) on learning English at multi-cultural classrooms in Korea. The participants were 32 KS, 10 CS, and 14 JS in EFL writing classes, and the data comprised open-ended questionnaires and interviews. In analyzing the data, 'Intentional content analysis' and 'Critical discourse analysis' were adopted. The findings show that the learning of English in Korea was supported by 80% of JS, 71.9% of KS, and 50% of CS. The highest satisfaction of JS was caused by rich interactions with others. English speaking was the most difficult area for all the groups. Whereas KS (43.8%) used only Korean, CS and JS used both English and Korean for communication. Most KS (78.1%) hesitated to socialize with foreign students despite their wishes. These findings suggest that a variety of programs should be developed so that students share different cultures and use more English in the multi-cultural Korean context.

Effects of English Programs in the Workplace on Employees' English Learning: A Case Study on In-Company English Programs in Korea (기업 내 영어 교육이 직장인의 영어 학습에 미치는 영향: 국내 대기업의 사내 영어 교육 프로그램 사례 연구)

  • Kim, Na-Young
    • Journal of Digital Convergence
    • /
    • v.15 no.5
    • /
    • pp.71-77
    • /
    • 2017
  • This study examines the effects of in-company English programs on Korean employees' English learning. During the twelve weeks, 68 employees in Korea engaged in an English learning program in the workplace. Before and after the program, pre- and post-tests were conducted to see if their English proficiency improved. Pre- and post-surveys and interviews were also administered to understand how they perceived the program. Results show that the employees improved their English oral proficiency and their attitudes toward English learning positively changed, as a result of participating in the program. Also, the program appeared to be successful, meeting their needs. Given that little research has investigated the effects of in-company English learning, this study provides insights on the effectiveness of English programs in the workplace in Korea.