생태계 기반 재난위험저감 (Ecosystem-based Disaster Risk Reduction; Eco-DRR)의 역할과 연구방안

김정욱,김형수,김수전,Kim, Jeong-Uk,Kim, Hyeong-Su,Kim, Su-Jeon 한국수자원학회 2020 물과 미래(한국수자원학회지) Vol.53 No.9

공공투자사업의 입·낙찰 분석

김정욱,Kim, Jungwook 한국개발연구원 2010 韓國 開發 硏究 Vol.32 No.2

공공투자사업에서는 최저가낙찰제, 턴키 제도, 대안입찰제 등 다양한 방식이 사용되고 있다. 최근 가격경쟁을 통한 효율성 제고를 주목적으로 하는 최저가낙찰제가 확대되어 시행되고 있다. 본 논문은 우리나라 입 낙찰 제도의 현황과 특징을 파악하고, 대형 공공투자사업에 주로 적용되는 최저가 낙찰제, 턴키 대안 입찰제도하에서의 가격 경쟁효과가 직접적으로 드러나는 낙찰률을 비교 분석하는 것에 의미가 있다. 각 입찰제도의 성과는 경쟁의 행태에 달려 있음을 고려하여 경쟁률과 낙찰률을 중심으로 여러 입찰제도의 입 낙찰 현황을 분석하였다. 1,000억원 이상 사업의 경우 최저가낙찰제하에서 평균 입찰참여자 수는 33.75명, 평균 낙찰률은 61.18%로 나타나, 턴키 대안 입찰제의 평균 입찰참여자 수 2.94명, 평균 낙찰률 90.20%와 큰 차이를 보였다. 최저가낙찰제의 경우 규모의 차이를 고려한다 하더라도 낙찰률이 현저히 낮으며, 경쟁의 정도가 심한 것을 확인할 수 있다. 이러한 낙찰률의 차이는 근본적으로 제도의 차이로 해석할 수 있으며, 경쟁의 차이로도 일부 해석할 수 있다. 민간투자사업의 경우, 평균 입찰참여자 수는 1.88명이며, 평균 낙찰률은 90%에 이르고 있어 경쟁 활성화를 통해 효율성을 제고할 여지가 있음을 제시하였다. This paper considers the effect of various types of procurement auction system on competition focusing on the rate of successful bidding. We analyze the number of bidders and the rate of successful bids using online procurement data of the Public Procurement Service. The average number of bidders is 301 and the average rate of successful bids is 87.42% while the weighted average rate is 75.13%. These numbers show that there is quite strong competition among bidders and the rate is lower as the expected price is higher. When we analyze the data of price procurement auction, the rate is also shown to be lower as the expected price is higher. Furthermore, the rate decreases as the number of bidders increases which naturally makes the competition stronger. Meanwhile, the analysis finds that the inclusion of the onsite bidding, the PQ(Pre-Qualification) result, or major-10 winning companies cannot explain the rate much in our data. In case of turnkey-alternative, the average rate of successful bidding for 484 cases record 90.20%. The average is 84.89% with 120 alternatives and 91.97% with 364 cases of turnkey. The reason why the rate of turnkey-alternative is lower than that of price procurement auction is the lack of competition as well as the systematic difference. By setting up a model, we are able to explain the difference in rate caused by the respective reason. When we suppose there are 3 bidders in case of price procurement auction for a project that exceeds 100 billion won, the rate is expected to be around 64%. This implies that difference of 26% is caused by the systemic difference and 3% by the lack of competition. Therefore, we conclude that the difference in rate between turnkey-alternative and price procurement auction is caused mainly by the systemic difference. In case of PPP(Public Private Partnership) projects, among 154 projects in total, only 40% has more than 2 bidders that compete. The average number of bidders is 1.88 which is less than 2, and the average rate of successful bids is 90%. In sum, under the price procurement auction, there is strong competition which is reflected by the rate of successful bids. However, there is room to decrease the rate by strengthening the competition under the turnkey-alternative. Also with PPP projects, we expect the rate can be steadily reduced with revived competition among bidders.

자연발생석면 분포지역의 효율적인 조사와 관리 방안

김정욱,정명채,김동진,전기석,이창환,Kim, Jeong-Wook,Jung, Myung-Chae,Kim, Dong-Jin,Jeon, Gee-Seok,Lee, Chang-Hwan 한국지하수토양환경학회 2011 지하수토양환경 Vol.16 No.6

This study presents a state of the art in evaluation on naturally occurring asbestos (NOA) areas and effective strategies for investigation and management of NOA areas in Korea. First of all, we defined and classified the NOA area as compiling various countries' regulations, then discussed the best methods for evaluation and management of NOA for reducing exposure of asbestos in the vicinity of NOA areas. According to the literature survey, a three-steps management strategy was suggested in this study. The first step is a confirmation stage of asbestos contamination possibility and the second step is an assessment stage of asbestos contamination using investigation, analysis, evaluation and reclamation. The final step is a following-up control stage. These three management steps for NOA area will give the maximum effectiveness of NOA control in Korea.

바닥충격음의 동향과 재료적 특성

김정욱,Kim, Jeong-Uk 한국화재보험협회 2005 방재기술 Vol. No.

건강관리코너 - 대장암의 조기진단과 예방

김정욱,Kim, Jeong-Uk 한국화재보험협회 2004 防災와 保險 Vol.103 No.-

강섬유 및 유기섬유를 혼입한 콘크리트 및 모르타르의 내충격 성능평가

김정욱,김규용,Miyauchi Hiroyuki,남정수,김홍섭 한국구조물진단유지관리학회 2011 한국구조물진단학회 학술발표회논문집 Vol.2011 No.9

In this study, it evaluate impact resistance performance of steel fiber and organic fiber reinforced concrete and mortar. The type of organic is polypropylene and polyvinyl alcohol. Percentage of fiber is 0.1, 0.5, 1.0%. It evaluate impact resistance performance to projectile 7, 10㎜ size and 350㎧ by high speed impact testing device.

다양한 전해액을 적용한 전기이중층 커패시터의 고전압 특성 연구

김정욱,최승현,김점수,Kim, Jung Wook,Choi, Seung-Hyun,Kim, Jeom-Soo 한국전기화학회 2017 한국전기화학회지 Vol.20 No.2

높은 출력의 장점을 가지는 전기이중층 커패시터 (EDLC: electric double layer capacitors)는 이차 전지와 더불어 차세대 에너지 저장장치로서 각광받고 있으나 낮은 에너지 밀도로 인해 그 사용처가 제한적이다. 본 연구에서는 EDLC의 에너지 밀도 향상 방법 중의 하나인 고전압화 구현 시 적합한 전해액을 연구하기 위해 AN (acetonitrile)용매에 $SBP-BF_4$ (spirobipyrrolidinium tetrafluoroborate), $TEA-BF_4$ (tetraethylammonium tetraflouroborate), $EMI-BF_4$ (1-ethyl-3-methylimidazolium tetrafluoroborate)의 세가지 염을 각각 선정하여 다양한 전해액의 조성에 따른 전기화학 특성을 비교 평가하였다. LSV (linear sweep voltammetry)측정에서 1.5M SBP-BF4/AN 전해액은 넓은 전위영역에서 안정함을 보였고, 고전압의 환경 (3.0 V 이상)에서 다른 조합의 전해액들과 비교하여 가장 우수한 전기화학적 성능을 보였다. 또한, 장기적으로 안정적인 성능을 유지하기 위해 리튬이온전지시스템에서 기능성 첨가제 효과가 입증된 TMSP (tris(trimethylsilyl)phosphite) 첨가제를 적용 했을 때 고전압의 환경 (3.3 V)에서 10,000 cycle 후 93%의 높은 용량 유지율을 얻을 수 있었다. Electric double layer capacitors (EDLC: electric double layer capacitors) have drew attention as an energy storage device for the next generation because of their outstanding power capability and durability. But their usage is somewhat limited due to low energy density over secondary batteries. One of methods to improve the energy of EDLC is expanding the voltage window of cell operation by increasing the charge cut-off voltage. In this study, $SBP-BF_4$ (spirobipyrrolidinium tetrafluoroborate), $TEA-BF_4$ (tetraethylammonium tetraflouroborate) and $EMI-BF_4$ (1-ethyl-3-methylimidazolium tetrafluoroborate) in AN (acetonitrile) were selected to evaluate the possibility of application at high voltage environment. The LSV (linear sweep voltammetry) measurements showed that the 1.5M SBP-BF4/AN electrolyte was stable over a wide potential window and showed the best electrochemical performance compared to other combinations of electrolytes at high voltage environments (over 3.0 V). Furthermore, TMSP (tris(trimethylsilyl) phosphite) was applied to 1.5M SBP-BF4/AN in order to maintain stable performance at high voltage for the long period of time. The electrolyte with TMSP additive showed the capacity retention of 93% after 10,000 cycles at 3.3 V.

물류운송산업 규제의 경제적 효과

김정욱,위서연,KIM, Jungwook,WI, Suhyeon 대한교통학회 2017 대한교통학회지 Vol.35 No.3

본 논문에서는 국내의 철도 항공 육로를 통한 물류운송산업 규제에 대해 살펴보고 여객 및 화물운송업 규제의 개선이 국민경제에 미칠 수 있는 영향을 계량화하고자 한다. 우리나라의 물류산업은 산출 및 생산규모가 점진적으로 확대되고 있으나 산업구조는 비교적 영세한 편이다. 한편 산업의 규제는 OECD 국가에 비해 높은 수준이며 국내의 여타 산업에 비해서도 그 수준이 높은 것으로 나타났다. 경제적 규제의 수준을 비교 제시한 OECD의 국가별 네트워크산업 규제지수를 살펴보면 우리나라의 물류운송산업 규제지수는 지난 40여 년 동안 점차 감소하였으나 여전히 EU, 일본, 미국 등의 국가보다 높은 수준이며 특히 철도물류에서는 가격규제와 진입규제가 상당한 것으로 파악되었다. 본 논문에서는 네트워크산업 중 하나인 물류산업의 규제 지수가 1인당 국내총생산에 미치는 효과를 고정효과 모형을 통해 분석하였다. 실증분석 결과 교통물류부문의 규제지수가 한 단위 개선될 경우 1인당 실질 GDP를 약 8.1% 증가시키는 효과가 있는 것으로 나타났다. 즉, 우리나라 물류운송산업 규제가 약 10%가량 개선될 경우 1인당 국내총생산을 2.16% 상승시키는 효과가 있을 것으로 추정되었다. 특히 이러한 개선효과는 우리나라와 같은 제조업 중심의 국가에서 경제적 규제의 개선에 대해 더욱 크게 나타날 것으로 기대되며 이를 실현하기 위해서는 물류 및 운송업 부문별로 구체적이고 신중한 규제개선 노력이 요구된다. This research reviews regulations on logistics/transport industry and attempts to quantify the effects of regulation mitigation on GDP per capita. South Korea's transport industry has been gradually expanding, however, the industrial structure is still short rooted. In 2014, average number of hours worked is 5th highest and wage margin 12th smallest out of 18 industries. Furthermore, the regulations for this industry appear to be stricter than those of other industries. OECD's logistics/transport industry regulatory index for South Korea has been decreasing for the last 40 years but still exceeds those of EU, Japan, US, and other countries. This paper provides supporting reasons for regulatory reforms by analyzing the ripple effects on real GDP. Factors such as the ratio of trade among GDP, the enrollment rate to primary school, energy usage per capita, and population are controlled in the fixed-effect model. Estimation results showed that 1 unit decrease in transport/logistics regulatory index is correlated with 8.1% increase of the real GDP per capita, that is, 10% of deregulation is expected to yield 2.16% increase in GDP per capita. Thus, it is expected that mitigating regulations on market entries, price determination, ownership structures of network industry, vertical integrations can improve the economy of South Korea.

19-norandrostenedione이 흰쥐 정소내 스테로이드 대사에 미치는 영향

김정욱,윤용달,Kim, Jeong-Wook,Yoon, Yong-Dal 대한생식의학회 1994 Clinical and Experimental Reproductive Medicine Vol.21 No.3

19-norandrostenedione(19-NORA) is known as an intermediate in the metabolic pathway from androstenedione to estrone. Administration of esterified 19-nortestosterone, anabolic steroid, reduces serum gonadotropin and testosterone concentration, and results in reversible azoospermia in men. 19-NORA have been isolated from testis, but its function in testis is not clear yet. Therefore, this study was designed to determine the effect of 19-NORA on steroidogenesis and on spermatogenesis. 19-NORA was administrated by single intratesticular injection to adult male rats weighing 350-400 g in dose of 1 mg/50${\mu}l$. The serum and testis were collected on 1, 3, 7, 12, 48 hr after injection. The histological differences in testis were observed by routine paraffin method. The concentrations of testosterone and estradiol in serum and in left testis were determined by the conventional radioimmunoassays. One hour after 19-NORA treatment, serum concentrations of testosterone and estradiol increased significantly, compared to those of pre-treated(0 hr) group, and reduced gradually to the control level on 7 hour after injection. The concentration of testosterone in left testis increased slightly 1 hour after injection, and estradiol level increased significantly(p<0.05). Also, testosterone and estradiol level of control group revealed no difference with pre-treated (0 hr) group. Gonad index, structure of seminiferous tubules, and the number of step 7 th spermatid were simillar to control group. The present study suggests that the elevation of testosterone level results from increment of estradiol followed by the rapid metabolism of 19-NORA at 7 hour after injection, and then testosterone concentration may be recovered to control level by feedback mechanism of hypothalamus-hypothysis-testis axis.

동결수정란 이식주기에서 수정란 융해 후 생존율과 임신율에 영향을 미치는 요인

김정욱,변혜경,염혜원,전진현,박용석,송인옥,송지홍,최범채,궁미경,전종영,강인수,Kim, Jeong-Wook,Byun, Hye-Kyung,Youm, Hye-Won,Jun, Jin-Hyun,Park, Yong-Seog,Song, In-Ok,Song, Ji-Hong,Choi, Bum-Chae,Koong, Mi-Kyoung,Jun, Jong-Young,Kang, 대한생식의학회 2000 Clinical and Experimental Reproductive Medicine Vol.27 No.1

Objective: The purpose of this study was to determine the important factors affecting survival and pregnancy rate in frozen-thawed embryo transfer cycles. Methods: we performed retrospective analysis in 738 cycles of frozen-thawed embryo transfers, in relation to the insemination methods, the freezing stage of embryo, patient's age, infertility factors and the origin of injected sperm in ICSI cycles. After conventional IVF or ICSI, the supernumerary PN stage zygotes or multicellular embryos were cryopreserved by slow freezing protocol with 1,2-propanediol (PROH) as a cryoprotectant. Results: The survival rates of thawed embryos were 69.3% (1585/2287) in conventional IVF group and 71.7% (1645/2295) in ICSI group. After frozen-thawed embryo transfers, 27.0% (92/341) and 32.0% (109/341) of pregnancy rates were achieved in conventional IVF and ICSI group, respectively. There were no significant difference in the survival and pregnancy rates according to the insemination methods, the freezing stage and patient's age. However, the pregnancy rate (36.2%) of male factor infertility was significantly higher than the tubal (27.2%) and other female factor infertility (22.9%). In ICSI group, the origin of injected sperm did not affect the outcome of frozen-thawed embryo transfer cycles. Conclusion: The present study demonstrates that acceptable clinical outcomes can be achieved after the transfer of frozen-thawed embryos regardless of the stage of embryos for freezing, the patient's age and the origin of injected sperm.