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Construction Delay Risk and its Prevention Measures

  • Acharya, Nirmal Kumar;Lee, Young-Dai;Im, Hae-Man
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2006년도 정기학술발표대회 논문집
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    • pp.268-270
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    • 2006
  • The purpose of this paper was to explore delay avoiding measures and strategies. The paper was based on previous work of authors on finding delay causes. Firstly, the paper has discussed about delay avoidance measures prescribed by the previous work. As the previous study identified five main causes of construction delays, various measures and strategies to overcome those delay problems have been discussed in sequence in the last sections. Major delay prevention strategies are: involving stakeholders in the project decisions, outreach program, realistic time and resource estimation, try to adjust the triple constraints of time, cost and scope, ensure fair and complete disclosure of information at an early stage of the construction project, contractor, itself should inquire about patent design errors prior to submitting its bid, owner should include in its contract with the consultant an indemnity (protection) clause etc.

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Improved Power Capability with Pyrolyzed Carbon Electrodes in Micro Direct Photosynthetic/Metabolic Bio-fuel Cell

  • Moriuchi, Takeyuki;Morishima, Keisuke;Furukawa, Yuji
    • International Journal of Precision Engineering and Manufacturing
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    • 제9권2호
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    • pp.23-27
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    • 2008
  • As a biofuel source, direct photosynthetic/metabolic biofuel cells (DPBFC) use cyanobacteria whose photosynthesis and metabolization reactions can convert light energy to electricity, In our previous work, we fabricated a prototype micro-DPBFC that could generate a peak current density of $36{\mu}A/cm^{2}$ and a maximum power density of $270nW/cm^{2}$. In this study, we improve on the previous results by using carbon micro electromechanical systems (C-MEMS), formed from the pyrolysis of patterned photoresist, to fabricate carbon electrodes of an arbitrary shape and controlled porosity to increase the surface area. With these new C-MEMS electrodes, the maximum power density of the micro-DPBFC was $516nW/cm^{2}$, a performance twice as good as the results of our previous work.

Thermal Performance of a Finned-tube Heat Exchanger used in Condensing Gas Boiler

  • Kang, Hie-Chan;Lim, Bok-Bin;Lee, Jung-Man;Kim, Moo-Han
    • International Journal of Air-Conditioning and Refrigeration
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    • 제17권2호
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    • pp.61-67
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    • 2009
  • In the present study, an experiment was conducted to investigate the heat and mass transfer performance of heat exchangers used in the condensing gas boiler. Two types of spiral circular fin-tube heat exchangers and a plain tube were tested in the flue gas of propane and dry air. Heat and mass transfer coefficients were measured and compared with the previous correlations. The experimental data for the sensible heat transfer of the plain tube reasonably agreed with the previous correlations for dry air and flue gas. However, the mass transfer coefficient of the plain tube was greater than the previous correlations. The pH, $NO_x$, and $SO_x$ data of condensate were provided.

잡음음성 음향모델 적응에 기반한 잡음에 강인한 음성인식 (Noise Robust Speech Recognition Based on Noisy Speech Acoustic Model Adaptation)

  • 정용주
    • 말소리와 음성과학
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    • 제6권2호
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    • pp.29-34
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    • 2014
  • In the Vector Taylor Series (VTS)-based noisy speech recognition methods, Hidden Markov Models (HMM) are usually trained with clean speech. However, better performance is expected by training the HMM with noisy speech. In a previous study, we could find that Minimum Mean Square Error (MMSE) estimation of the training noisy speech in the log-spectrum domain produce improved recognition results, but since the proposed algorithm was done in the log-spectrum domain, it could not be used for the HMM adaptation. In this paper, we modify the previous algorithm to derive a novel mathematical relation between test and training noisy speech in the cepstrum domain and the mean and covariance of the Multi-condition TRaining (MTR) trained noisy speech HMM are adapted. In the noisy speech recognition experiments on the Aurora 2 database, the proposed method produced 10.6% of relative improvement in Word Error Rates (WERs) over the MTR method while the previous MMSE estimation of the training noisy speech produced 4.3% of relative improvement, which shows the superiority of the proposed method.

Modified Scheme for Tsunami Propagation with Variable Water Depths

  • Ha, Tae-Min;Seo, Kyu-Hak;Kim, Ji-Hun;Cho, Yong-Sik
    • 한국수자원학회논문집
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    • 제44권6호
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    • pp.471-476
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    • 2011
  • In this study, a modified dispersion-correction scheme describing tsunami propagation on variable water depths is proposed by introducing additional terms to the previous numerical scheme. The governing equations used in previous tsunami propagation models are slightly modified to consider the effects of a bottom slope. The numerical dispersion of the proposed model replaces the physical dispersion of the governing equations. Then, the modified scheme is employed to simulate tsunami propagation on variable water depths and numerical results are compared with those of the previous tsunami propagation model.

A Study of a Simple PDP Driver Architecture using the Transformer Network

  • Kim, Woo-Sup;Shin, Jong-Won;Chae, Su-Yong;Hyun, Byung-Chul;Cho, Bo-Hyung
    • Journal of Power Electronics
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    • 제8권2호
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    • pp.148-155
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    • 2008
  • In this paper, a cost-effective PDP driving circuit using the transformer network is proposed. Compared with the previous works, the half-bridge type energy recovery circuit recovers the reactive energy not to the capacitor but to the source. A single sustain board architecture removes the blocking switches which are placed on the discharge path in parallel, thus reducing the number of devices. A simple reset circuit generates the same waveforms as the previous approaches. The circuit configuration and modified driving waveforms are compared with the previous works. The validity of the proposed simplified driver is verified through tests using a 6-inch panel.

The Impact of Housing Prices and Private Education Costs on Fertility Rates

  • Clara Jungwon Choi;Jaehee Lee;Jinbaek Park
    • International Journal of Advanced Culture Technology
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    • 제12권2호
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    • pp.62-71
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    • 2024
  • The Study analyzed the effect of private education costs and housing prices on the total fertility rates in 16 metropolitan cities in Korea from 2009 to 2021, and estimated the contribution rates of each variable on the decrease in the total fertility rate. Using a dynamic panel data model considering the time series correlation of the total fertility rates, the total fertility rates for the year was positively (+) affected by the total fertility rates of the previous year, and the increase in apartment sales and Jeonse prices in the previous year reduced the total fertility rates. In addition, the increase in private education costs per capita in the previous year was analyzed to consistently reduce the total fertility rates.

Visitors Satisfaction With Entrance In Soraksan National Park

  • Jo, Tae-Dong
    • 한국환경과학회지
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    • 제13권2호
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    • pp.129-134
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    • 2004
  • Understanding aspects of the use of Korean representative Soraksan National Park and investigating the factors affecting visitors' decision-making, this study aims to suggest a positive development plan for the rational use of the national park. The questionnaire is for those who have visited Soraksan National Park more than once. This research shows that most of the visitors wish ‘entrance congestion’ to be solved by introducing a ‘previous reservation’ system and a non-polluting shuttle bus; therefore there is a chance that they could be introduced for the settlement of the existing problems.

국내기업의 지식자산 측정 모델 개발 연구 (A Study on the Knowledge Assets Measurement Model for Korean Companies)

  • 양경식;김현수
    • 정보기술과데이타베이스저널
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    • 제8권2호
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    • pp.115-135
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    • 2001
  • The objective of this paper is to develop a knowledge assets measurement model in Korea. There are relatively many researches on measuring knowledge assets of an organization. These previous researches, however, lack of comprehensive view of knowledge management and view of Korean organizational culture. We surveyed and analyzed previous researches, and found common factors to measure knowledge assets. We developed an updated version of knowledge assets index. The developed model has been validated for its fitness with real data of Korean companies. The result of this research can be used as a measurement tool for knowledge assets of public institutions as well as private companies.

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비진언성 이론에 입각한 부정극어 연구 (An Analysis of NPIs based on Nonveridicality Theory.)

  • 김미자
    • 한국영어학회지:영어학
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    • 제2권4호
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    • pp.495-518
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    • 2002
  • This paper is to analyze various phenomena of NPIs based on Nonveridicality Theory. For this purpose, I present the previous studies concerning NPls and examine their problems: Ladusaw's(1980) Downward Entailment and Zwarts'(1993) Monotonicity Theory. To solve their problems I suggest Giannakidou's(1998, 1999, 2000) Nonveridicality Theory. To conclude, this paper clarifies the reason why NPls are licensed and resolves the problems of previous studies. I explain NPIs' phenomena in questions, modals, intentional verbs, before, perhaps and so on. I analyse the examples of NPls in BNC, S&S, P&P to prove my claim.

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