입력전류 파형 개선형 단상 정류기의 토폴로지

이상현(Sang-Hyun Lee),박진민(Jin-Min Park),문상필(Sang-Pil Mun),서기영(Ki-Young Suh) 한국조명·전기설비학회 2003 한국조명·전기설비학회 학술대회논문집 Vol.2003 No.-

For small capacity rectifier circuits such as these for consumer electronics and appliances, capacitor input type rectifier circuits are generally used. Consequently, various harmonics generated within the power system become a serious problem. Various studies of this effect have been presented previously. However, most of these employ switching devices, such as FETs and the like. The absence of switching devices makes systems more tolerant to over-load, and brings low radio noise benefits. We propose a power factor correction scheme using a LC resonant in commercial frequency without switching devices. In this method, it makes a sinusoidal wave by widening conduction period using the current resonance in commercial frequency, Hence the harmonic characteristics can be significantly improved, where the lower order harmonics, such as the fifth and seventh order are much reduced. The result are confirmed by the theoretical and experiment implementations.

한국철도의 효율적인 경영과 민영화

조한필(Han Pil Cho),이성환(Sung Hwan Lee) 한국물류학회 2012 물류학회지 Vol.22 No.5

우리나라는 100년 이상 건설과 운영을 함께 담당해오던 국유철도시대를 마감하고 2004년 시설과 운영을 분리하는 철도구조개혁 조치를 단행했지만 막대한 규모의 계속적인 누적 부채 발생으로 만성적인 경영적자 구조에서 벗어나지 못하고 있다. 이에 정부는 KTX 운영권의 민간 개방 등 제 2 철도구조개혁을 위한 민영화를 추진하고 있다. 그러나 이명박 정부가 현재 추진하고 있는 KTX 동일노선에 대한 경쟁체제 도입 방안은 세계적으로 사례를 찾기 어렵고 근본적인 방안으로 미흡한 것이 사실이다. 특히 정부의 민영화 방식은 장기적으로 운임상승과 철도공사의 부채해결 대책이 없고 KTX 운영권의 민간 개방에 따른 사업면허 등 법적 근거 미약 등 정치적, 법적 여러 논란을 빚고 있다. 이에 따라 현 단계에서 분명히 고려되어야 할 것은 철도 운영 경영효율화이며 민영화를 위한 사회적 합의와 기대효과에 대한 긍정적 비전을 제시하는 것이 중요한 것으로 인식했다. 본 연구는 영국, 일본 등 외국의 철도민영화 사례의 시사점을 토대로 우리나라 철도경영의 효율적인 민영화를 위한 방안을 분석, 검토했다. 이미 시설과 운영주체가 분리되어 안정적으로 역할을 수행하는 상황에서 3,381km에 불과한 영업거리 등 취약한 인프라와 현실을 감안하여 국가의 철도투자 책임을 명확히 한다는 측면에서도 지역별, 노선별 분할 민영화보다는 철도운영주체의 일괄적인 책임제민영화 방식으로 추진하는 것이 타당한 것으로 사료된다. Korean railroad has come to the end of government construction and operation management era in 2004 and the railroad system reformation measures was carried out the way of separating the infrastructure from the operation management. But operation deficit continues due to a large accumulated debt. This led the government to push ahead privatization of KTX management for ‘the Second Railroad System Reformation’ through partial privatization. However, President Lee’s government’s current proposal for shared KTX lines is unprecedented anywhere around the globe and is still immature to be implemented as the primary solution. Specifically, the government’s privatization plan does not address any issues regarding future increase in fares and Korean railroad’s debt pay-off in the long run. Also, there are many political and legal conflicts rising from lack of legal grounds such as business license for partial privatization of KTX operation management and solutions for management failure of KORAIL and debt-generating lines. It is necessary at this point to consider the ‘management efficiency’ of the railroad and it is also important to suggest positive vision about privatization to satisfy the social expectations and achieve social and political agreements. This study has analyzed and reviewed ways of effectively privatizing Korea’s railroad management based on implications from previous privatization cases in the U.K and Japan. Based on the fact that infrastructure and operation managements are naturally separated following the train-railroad separation and the fact that the infrastructure management is stable and the operation distance is only 3,381km, it seems more effective to privatize the operation management as a whole rather than executing multiple privatizations of operation management system based on the operating areas and lines.

배추의 형질전환용 선발항생제로서 Paromomycin의 이용

조미애,민성란,고석민,유장렬,이준행,최필선,Cho, Mi-Ae,Min, Sung-Ran,Ko, Suck-Min,Liu, Jang-Ryol,Lee, Jun-Haeng,Choi, Pil-Son 한국식물생명공학회 2006 식물생명공학회지 Vol.33 No.4

정상' 배추와 '서울' 배추의 배축절편을 선발마커로서 hygromycin 저항성유전자를 갖고 있는 pCAMBIA1301와 paromomycin저항성유전자를 갖고 있는 pPTN290으로 각각 형질 전환된 LBA4404 또는 EHA101균주와 공동배양한 후 선발배지에서 배양하면서 형질전환체를 선발하였다. 형질전환빈도는 사용된 항생제와 품종에 따라서 현저하게 차이가 있었으며, 특히 paromomycin은 hygromycin보다 효과적이었고 정상 배추는 서울배추보다 양호하였다. 가장 높은 형질전환빈도는 (0.70%) 100mg/L paromomycin이 첨가된 선발배지에서 정상배추의배축을 배양할 경우 얻어졌다. GUS양성반응으로 확인 한 결과 정상배추에서 9개체와 서울배추에서 3개체를 각각 얻었으며, 온실에서 생장한 후 $T_1$종자를 수확하였다. $T_1$ 종자를 다시 발아시켜 유식물체를 얻은 후 GUS양성반응을 확인함으로서 외래유전자가 안정적으로 발현하고 있음을 확인하였다. Hypocotyl explants of Chinese cabbage (us. 'Jeong Sang' and 'Seoul') produced adventitious shoots on Murashige and Skoog (MS) basal medium supplemented with 4mg/L $AgNO_3$, 5 mg/L acetosyringone, 4 mg/L 6-benzyladenine and 3mg/L alpha-naphthaleneacetic acid (SI) after cocoultivation with strains of Agrobacterium tumefaciens (LBA4404) harboring the pCAMBIA1301 and the $_PPTN290$ containing hygromycin-resistance gene and paromomycin-resistance gene as a selectable marker genes, respectively. There was a significant difference in the frequency of transgenic plants depending on antibiotics and cultivars used. Paromomycin was better than hygromycin, and cultivar 'Jeong-sang' was higher than 'c.v. Seoul' in the frequency of transgenic plants. In particular, the highest frequency (0.70%) of transgenic plants was obtained from selection medium (SI) containing 100mg/L paromomycin in c.v., 'Jeong-sang' GUS positive response were obtained 9 plants and 3 plants from the cultivars, 'Jeong-sang' and 'Seoul', respectively. They were grown to maturity in a greenhouse and normally produced $T_1$ seeds. GUS histochemical assay for progeny $(T_1)$ revealed that the transgenes were expressed in the plant genome.

Long-term clinical study and multiscale analysis of in vivo biodegradation mechanism of Mg alloy

Lee, Jee-Wook,Han, Hyung-Seop,Han, Kyeong-Jin,Park, Jimin,Jeon, Hojeong,Ok, Myoung-Ryul,Seok, Hyun-Kwang,Ahn, Jae-Pyoung,Lee, Kyung Eun,Lee, Dong-Ho,Yang, Seok-Jo,Cho, Sung-Youn,Cha, Pil-Ryung,Kwon, H National Academy of Sciences 2016 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.113 No.3

<P>There has been a tremendous amount of research in the past decade to optimize the mechanical properties and degradation behavior of the biodegradable Mg alloy for orthopedic implant. Despite the feasibility of degrading implant, the lack of fundamental understanding about biocompatibility and underlying bone formation mechanism is currently limiting the use in clinical applications. Herein, we report the result of long-term clinical study and systematic investigation of bone formation mechanism of the biodegradable Mg-5wt% Ca-1wt% Zn alloy implant through simultaneous observation of changes in element composition and crystallinity within degrading interface at hierarchical levels. Controlled degradation of Mg-5wt% Ca-1wt% Zn alloy results in the formation of biomimicking calcification matrix at the degrading interface to initiate the bone formation process. This process facilitates early bone healing and allows the complete replacement of biodegradable Mg implant by the new bone within 1 y of implantation, as demonstrated in 53 cases of successful long-term clinical study.</P>

Postoperative adjuvant chemotherapy is associated with a lower incidence of colorectal adenomas in patients with previous colorectal cancer

Lee, Hee Seung,Kim, Sung Bae,Lee, Hyun Jung,Park, Soo Jung,Hong, Sung Pil,Cheon, Jae Hee,Kim, Won Ho,Kim, Tae Il Elsevier 2018 Gastrointestinal endoscopy Vol.87 No.3

<P><B>Background and Aims</B></P> <P>The effects of chemotherapeutic agents on the development of colorectal adenomas in patients with previous colorectal cancer (CRC) are not defined. Therefore, we evaluated the potential effect of adjuvant chemotherapy on the incidence of colorectal adenomas in patients with previous CRC.</P> <P><B>Methods</B></P> <P>We selected patients with low-risk stage II CRC with or without postoperative 5-fluorouracil–based adjuvant chemotherapy to reduce selection bias. Among 1808 patients with stage II CRC who underwent colonoscopic surveillance after curative resection of CRC between 2006 and 2013, 192 patients were retrospectively enrolled in this study after matching for age and sex. The patients were divided into 96 patients receiving and 96 patients not receiving 5-fluorouracil–based chemotherapy.</P> <P><B>Results</B></P> <P>Forty patients (41.7%) exhibited colorectal adenomas among 96 patients who received adjuvant chemotherapy, compared with 50 patients (52.1%) with colorectal adenomas among 96 patients who received surgery only. The incidence rate of advanced adenoma was significantly lower in the chemotherapy group than in the nonchemotherapy group (3.1% vs 10.4%, <I>P</I> = .044). After adjustment for clinically relevant factors such as body mass index, aspirin use, metformin use, number of follow-up colonoscopies, and operation type, adjuvant chemotherapy was found to be associated with a decreased incidence of advanced adenoma (odds ratio, .151; 95% confidence interval, .035-.653; <I>P</I> = .011) in patients with stage II CRC.</P> <P><B>Conclusions</B></P> <P>The results showed that chemotherapy in patients with CRC may be associated with a lower risk of colorectal advanced adenoma development.</P>

Increasing the storage density of a page-based holographic data storage system by image upscaling using the PSF of the Nyquist aperture

Lee, Sang-Hyuck,Lim, Sung-Yong,Kim, Nakyeong,Park, No-Cheol,Yang, Hyunseok,Park, Kyoung-Su,Park, Young-Pil The Optical Society 2011 Optics express Vol.19 No.13

Evaluation of Electrochemical Treatment of Chloride Contaminated Mortar Containing GGBS

Lee, Ki Hong,Jung, Young Hee,Hwang, Jun Pil,Sim, Jong Sung Hindawi Limited 2017 Advances in materials science and engineering Vol.2017 No.-

<P>The present study concerns the influence of cementitious binder on electrochemical treatment of steel embedded in salt contaminated mortar. As binder, ordinary Portland cement (OPC) and ground granulated blast furnace slag (GGBS) were used and the current density of 250–750 mA/m<SUP>2</SUP> was applied for 4 weeks to complete electrochemical chloride extraction. To evaluate the effect of electrochemical treatment the chloride profile and corrosion behaviour covering chloride concentration, galvanic current density, linear polarization resistance, open circuit potential, and mass loss were measured. An increase in the applied direct current density resulted in a decrease in the chloride concentration at the vicinity of steel, accompanying the mitigated corrosion damage. The performance of electrochemical treatment was more remarkable in mortar containing GGBS presumably due to binding mechanism. However, corrosion damage was more detrimental in GGBS rather than OPC at a given potential, while GGBS had superior corrosion resistance to a corrosive environment and treatment conditions. Therefore, the electrochemical treatment should be conducted prudently to evaluate the corrosion state of embedded steel depending on binder type.</P>

Effects of corn dried distiller's grains with solubles and enzyme premix supplements on growth performance, carcass characteristics and meat quality parameters in finishing pigs

LEE, Sung Dae,JUNG, Hyun Jung,CHO, Kyu Ho,PARK, Jun Cheol,KIM, In Cheul,SEONG, Pil Nam,SONG, Young Min Blackwell Publishing Asia 2011 ANIMAL SCIENCE JOURNAL Vol.82 No.3

<P><B>ABSTRACT</B></P><P>The objective of the present study was to investigate the effects of corn dried distiller's grains with solubles (DDGS) and enzyme premix (mannanase + phytase) supplementation on the growth performance, carcass and meat quality parameters in finishing pigs. Sixty hybrid pigs (L × LW × D) with initial weight of 63.92 ± 1.50 kg were used in a 3 × 2 factorial design with main effects of DDGS levels (0, 10 and 20%) and enzyme premix levels (0% <I>vs</I>. 0.14%). Average daily gain (ADG, <I>P</I> < 0.01) and average daily feed intake (ADFI, <I>P</I> < 0.05) were decreased due to an increased level of DDGS additive while the feed conversion ratio was improved (<I>P</I> < 0.05) by adding enzyme premix. The diet cost/gain (won/kg) was saved (<I>P</I> < 0.01) due to an increased level of DDGS additive. There were no significant differences in carcass characteristics and meat quality parameters of Longissimus dorsi muscle by DDGS level and enzyme premix. Palmitoleic acid, oleic acid and monounsaturated fatty acid (MUFA) decreased (<I>P</I> < 0.05) according to DDGS level. The results indicate that DDGS may be used in feeds for finishing pig as a replacement of corn and soybean meal without affecting their carcass characteristics and meat quality.</P>

Protective effect of Cinnamonum cassia against cell toxicity induced by styrene in GC-2spd(ts) spermatocytes

Sang-Hyun Sohn,Pil-Sang Park,Young-Ock Kim,Seung-Ok Yang,Yu-Su Shin,Hyung-Don Kim,Min-Sol Kim,Seung-Yu Kim,Sang-Won Lee 한국약용작물학회 2013 한국약용작물학회 학술대회논문집 Vol.2013 No.1

Tumebacillus avium sp. nov., isolated from the gut of a cinereous vulture, Aegypius monachus

Sung, Hojun,Kim, Hyun Sik,Lee, June-Young,Kang, Woorim,Kim, Pil Soo,Hyun, Dong-Wook,Tak, Euon Jung,Jung, Mi-Ja,Yun, Ji-Hyun,Kim, Min-Soo,Shin, Na-Ri,Whon, Tae Woong,Rho, Jeong Rae,Park, Sun Duk,Shim, Microbiology Society 2018 International journal of systematic and evolutiona Vol.68 No.5