• Journal of Korean Society of Transportation
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• v.17 no.1
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• pp.173-185
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• 1999

The purpose of this study is to develope a forecasting model to implement short-term Congestion Management Program (CMP) based on TDM strategies in Seoul. The CMP is composed of three elements: 1) setting a goal of short-term traffic management. 2) developing a model to forecast the impacts of TDM alternatives, and 3) finding TDM measures to achieve the goal To Predict the impacts of TDM alternatives, a model called SECOMM (SEoul COngestion Management Model) is developed. The model assumes that trip generation and distribution are not changing in a short term, and that only mode split and traffic assignment are affected by TDM. The model includes the parameter values calibrated by a discrete mode choice model, and roadway and transit networks with 1,020 zones. As a TDM measure implement, it affects mode choice behavior first and then the speeds of roadway network. The chanced speed again affects the mode choice behavior and the roadway speeds. These steps continue until the network is equilibrated. The study recommends that CMP be introduced in Seoul, and that road way conditions be monitored regularly to secure the prediction accuracy of SECOMM. Also, TDM should be the major Policy tools in removing short-term congestion problems in a big city.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2000.04a
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• pp.457-460
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• 2000

주가를 예측하는 것은 이미 오래 전부터 여러 가지 방법으로 시도되어 왔었다. 기업의 본질가치를 보는 기본적 분석부터 과거의 자료를 가지고 미래를 예측하는 기술적 분석까지 많은 연구가 있었으나 실제로 모든 예측이 그렇듯이 많이 적중을 했다는 것을 일부의 정형화된 분석방법을 제외하고는 찾지 못하였다. 그럼에도 불구하고 이번 연구에서는 기술적 분석에서 많은 요인들 중에서 기존에 많이 연구해 보지 못한 시계열적인 인자를 가지고 단기간의 주가를 예측하고자 한다. 주식이 상한가에 도달하였을 경우 그 상한가격의 잔량과 그 주식의 일일거래량을 비교하여 그 서로 두 관계가 다음날 주가에 어느 정도의 영향을 미치는지 회귀분석을 통하여 상관성을 분석하고 통계적 자료를 토대로 단기간의 주가를 상한 잔량 대비 일일거래량에 비추어 의사결정 지표를 제시하려고 한다. 적절한 예측결과가 나오게 되면 주식에 대해 매수를 희망하는 사람 뿐 아니라 주식을 보유하고 있는 사람에게 어느 정도 정보효과가 미치게 될 것이라 기대한다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.534-541
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• 2002

The use of triorganotins as insecticides, bacteriocides, and antifouling agents has increased dramatically over the past 30 years, In this paper, to evaluate the acute and chronic toxicity effects of various triorganotins (TBTO, TBTE, CTPT, TBTCI) on the growth of microalgae, Skeletonema costatum, we carried out the short term and long term experiments, respectively. In the short-term experiments, the growth of S. costatum was inhibited by the various triorganotins in the dose dependent manners, but recovered by the time laps. The growth inhibition of triorganotins were decreased in the groups with higher initial cell density. These data were resulted from the dilution effect and the biodegradation of triorganotins by the microalgae. In the long-term experiments, S. costatum died completely at the 1 $\mu$g/L of TBTP and CTPT, but didn't in short-term experiments. The facts suggest that the toxicity of the chronic exposure of triorganotins should be increased in the natural sea water with low phytoplankton density.

• Information Systems Review
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• v.21 no.2
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• pp.51-67
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• 2019

This study examines IPO underpricing and its interaction with investor attention as one of key factors that can affect post-IPO performance in the short- and long-run. With higher investor attention measured as Google searches around IPO dates, our empirical results show that IT firms are underpriced more severely than non-IT firms. We also demonstrate that investor attention is positively associated with IPO performance in the short-run for both IT and non-IT firms. However, the impact of investor attention is more sustained for IT firms over a longer time horizon when coupled with a high level of underpricing while its impact is neutralized for non-IT firms. Given the unique attributes such as network effects embedded in the IT industry, our findings suggest that IPO underpricing and its interplay with investor attention for IT firms play an important role in shaping long-run performance and ultimately affecting fundamental value.

• Journal of Technology Innovation
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• v.22 no.2
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• pp.77-104
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• 2014

Government R&D support for SMEs is very important and the R&D budget is also increasing. This study suggests a new method for analyzing a performance of R&D programs and analyzes the performance of R&D programs funded by small & medium business administration using the method. We discuss new measures "efficiency" that means short-term performance and "effectiveness" that means long-term performance. Weights based on the R&D programs' characteristics among the various sub-indicators of two measures were derived, and then the final scores were calculated by combining the weights with the responses on the indicators. Finally, this study tests the mean differences between R&D programs statistically. As a results, efficiency of R&D programs shows a significant difference between the R&D programs, while effectiveness does not. Most of the efficiency scores are low, whereas the effectiveness scores are high. The results explain that the R&D programs are managed inefficiently. However, most SMEs predict a positive impact of government R&D supports on effectiveness in the long term. Government needs to try to improve the efficiency of R&D supports because SMEs cannot expect sustainable performance with no improvement in efficiency.

• 한국경영정보학회:학술대회논문집
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• 2008.06a
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• pp.827-832
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• 2008

IT성과는 정보시스템 구축 가동 후 상당기간이 경과되어야 제대로 나타나는 경우가 일반적이며, 아무리 근거리의 성과지표에 의한다 하더라도 단기적으로는 여전히 조직 내외의 다른 영향요인들에 의해 상쇄 효과(Smooting Effect)가 나타날 수 있다. 특히 IT 성과를 사후적으로 평가하고자 하는 방법론에서 시차를 고려하지 않고서는 정확한 IT 성과를 측정하기 어렵다. 본 연구에서는 정보화 성과평가에 있어 시차적 특성을 어떻게 효과적으로 분석할 수 있는지에 대해 알아보고자 한다. 이를 위해 시차의 개념이 도입된 정보화 성과평가 방법론을 토대로 성과평가를 실시한 공공 기관의 정보시스템 6개를 대상으로 시차분석에 대한 사례연구를 실시하였다.

• Environmental and Resource Economics Review
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• v.6 no.1
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• pp.59-86
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• 1996

본(本) 연구에서는 에너지절약을 위한 주요 정책수단(政策手段)인 저리융자나 세제감면 또는 특별감가상각 인정 등 에너지절약 비용측면의 금융 세제지원이라는 과인성(課引性)정책과, 에너지수요조절를 위한 에너지가격 규제해제(energy price deregulation)나 에너지세(稅)의 추가부과 등 가격관리(조세) 정책의 경제적 효과를 비교 분석하였다. 그리고 에너지세(稅)부과의 경우 과세단계별 효과분석을 통하여 바람직한 과세포인트를 선택하고, 이를 통하여 현행 에너지절약 지원(支援)정책이나 에너지가격 및 조세체계에 대한 개선방향을 모색하였다. 분석결과, 약간의 물가상승 압박효과를 감수하더라도 에너지가격통제 해제나 에너지세 부과가 금융 세제지원제도에 비하여 에너지절약에 있어 그 효과가 크게 나타났다. 또한 에너지과세의 경우 그 대상과 실행시기에 대해서도 신축성을 기하는 것이 바람직한 것으로 나타나 에너지의 소비감소라는 효율성 측면과 함께 수반되는 물가압박요인을 고려하여 신중히 결정되어야 할 것으로 보인다. 그렇지만 단기적으로 에너지가격의 상승을 감수하더라도 DSM 프로그램비용을 자본화해 나감으로써 점진적으로 가격상승요인을 흡수하고 효과적인 에너지소비의 절약을 통하여 국민경제의 에너지비용을 줄여나갈 수 있는 종합적인 에너지대책이 마련되어야 할 것이다.

• Tuberculosis and Respiratory Diseases
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• v.43 no.6
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• pp.852-861
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• 1996

Background : Many clinicians have experienced the difficulty of decision on termination of antituberculosis chemotherapy after the 6th month due to relapse of disease. There is still controversy in the effect of 2S(K)HRZ/4HRZ 6-month short course chemotherapy including pyrazinamide for 6 months in patiems with pulmonary tuberculosis. And there is no long term follow-up study of 6-month short course chemotherapy for pulmonary tuberculosis in korea. So we had performed the study to find the result of 6-month antituberculosis chemotherapy for 4 years. Method : We studied prospectively the effect of 2S(K)HRZ/4HRZ in one hundred-fifty patients with pulmonary tuberculosis and followed up fifty-nine patients for more than 1 year to 4 years after the completion of 6-month short course therapy. Results : 1) Out of one hundred-fifty patients, seventy-two patients(48%) completed the prescribed 6-month chemotherapy. Sixty-eight patients(45.3%) have experienced premature discontinuation and the most common cause of premature discontinuation was drop-out against advice(thirty-six patients, 24%). Ten patients(6.7%) were treated beyond the 6 months mainly due to irregular treatment. 2) Fifty-nine patients(81.9%) among seventy-two patients with completed treatment have been followed up for more than 1 year and 32 patients(44.4%) for more than 4 years. There was three relapse patients of whom two patients have experienced relapse of pulmonary tuberculosis within 1 year after the termination of chemotherapy. 3) Among one hundred-thirty-four patients who have been assessible for more than two months of chemotherapy, including the patients who experienced within 2 months, there were eighty-two patients(61.2%) who have experienced adverse reactions and the treatment regimen was changed only in thirteen patients(9.7%). The most frequent cause of adverse reactions was arthralgia and/or hyperuricemia, which had occurred in 33 patients(24.6%). Conclusion : In a university hospital in Korea, 6-month shot course chemotherapy of 2S(K)HRZ/4HRZ had unnegligible relapses and premature discontinuation. Therefore, change of the regimen might be carefully considered by drug susceptibility results. Close monitoring of patients, retrial of sputum exam and radiologic evaluation during treatment might be required in the endemic area of drug resistant strains like in Korea. Further study about the effect of 6-month short course chemotherapy including pyrazinamide for 6-month might be needed.

• Korean Journal of Childcare and Education
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• v.11 no.1
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• pp.289-303
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• 2015

The aim of this study was to examine the short-term longitudinal effect of creativity-fostering programs for pre-early childhood teachers on their problem solving ability and self-efficacy. The participants of this study were 67 pre-early childhood teachers (36 from the experimental group and 31 from the control group) in Seoul, Kyunggi-do, and Chungcheong-do, Korea. Pre-early childhood teachers' problem solving ability and self-efficacy was measured three times. Data were analyzed with a $2{\times}3$ ($group{\times}test$) two-way analysis of variance for repeated measures. The change in problem solving and self-efficacy appeared to be dependent on the group and test. Further statistical analysis of the data indicated that the participation of creativity-fostering programs for pre-early childhood teachers was longitudinally effective on their problem solving ability and self-efficacy.

• 보일러설비
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• s.80
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• pp.62-64
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• 2000

정부는 연말까지 대체에너지 보급목표 1.1${\%}$를 달성키 위해 중점기술분야에의 집중투자와 확보된 기술의 보급 확대를 적극 추진하고, 에너지 기술개발 10개년 계획의 실효성있는 수정보완을 통해 기술분류체계 개선 등 전략적 지원 방안을 모색하며, 기술의 중요성과 파급효과가 큰 중심기술 분야와 단기실용화가 가능한 일반 추진분야로 분류할 계획이다.