특수공작기계에서 쇼트피닝기의 특성 및 투사속도에 관한 연구

노승남,이승호,서유원 서울산업대학교 산업대학원 2000 大學院論文集 Vol.7 No.-

As developing the technology in industry, the materials with superior grade of stiffness and lightness are required, and hence the higher fatigue strength characteristics are necessary. Thus, the non-traditional machining to increasing fatigue strength is becoming influence as very important technology. Shot peening process is essential to ensure repeatability and uniformity on a part to part and lot to lot basis, while conforming to the applicable specifications. The shot material, size, shape and hardness as well as velocity and impact angle must be rigidity controlled to provide consistency in peening results. High velocity of the shot ball increases the impact energy, the shot peening intensity increase. Comparing with the are height for the velocity 42m/sec, the are height for 56m/sec and 70m/sec increase 33% and 48% respectively.

수술후 경막외강에 주입한 ketamine의 진통효과에 관한 연구

정기호,조남수,임경준,유병식,정종달,김용일 朝鮮大學校 附設 醫學硏究所 1993 The Medical Journal of Chosun University Vol.18 No.1

Author divided 60 patients who got lower abdomen or lower extremity surgical operation into three groups. Each group consisted of 20 patients. We injected ketamine 10㎎, 20㎎, and 30㎎ respectively into the epidural space when the patient complained of pain postoperatively and observed the postoperative analgesic effect of ketamine. Finally, we concluded the following : 1) The onset time of analgesic effect. : The analgesic effect appeared within 10 minutes in 3 groups and the significant difference among them was not seen. 2) The duration of analgesic effect : The duration of analgesia was relatively short with less than 1 hour on an average in all 3 groups and was not constant. 3) Cardiopulmonary system. : The significant change of blood pressure, pulse and respiratory rate was not seen in all three groups and and the difference among them also was not seen. 4) Side effects. : Sedative action(16%), nausea(10%), dizziness(5%), headache(3.3%) From above results, the epidural administration of ketamine is not suitable for postoperative pain management because of a lot of side effects as well as short and inconstant duration of analgesic effeet.

유해화학물질의 계통분석

박성우,박유신,이진훈,김남이,김유나,임미애,이상기,유재훈,진광호,신호상,노동석 內務部 國立科學搜査硏究所 2001 國立 科學 搜査 硏究所 年報 Vol.33 No.-

중증 만성정신질환자 수의 추산 : Through Two Community Surveys 두 지역사회 조사를 중심으로

홍진표,김윤,배재남,정유진,강영호,양병국,김용익,김병후,이철,조맹제 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.2

국내 중증 만성정신질환자 수를 추정하기 위하여 일 농촌 및 대도시 지역의 지역의료보험 및 의료보호 대상자 중 1993년 1년간 의료기관에서 정신증 상병(ICD-9 code 상 290-299) 및 알콜 남용/중독, 성격장애 및 정신박약 진단하에 치료를 받은 적이 있는 사람에 대해 설문조사를 실시하였다. 연구자들이 개발한 진단도구를 이용하여 진단을 평가하고, Strauss-Carpenter scale 등을 이용하여 기능 장애를 평가하고 유병기간 등을 조사하였다. 결과를 요약하면 다음과 같다. 1) 진단평가상 정신분열병군(61.1%)이 가장 많았으며, 정동장애군(23.7%), 알콜장애군(11.2%), 기질성 정신장애군(4.0%)의 순서이었다. 2) 직업활동정도는 진단군별로 차이가 많았다. 지난 1년간 직업활동이 6개월 미만이거나 전혀 없는 환자 비율이 정신분열병군은 67.2%, 알콜장애군 52.0%, 정동장애20.8%의 순으로 정신분열병군이 가장 불량하였다. 3) 사회활동도 진단군별로 차이가 많아서 지난 1년간 의도적, 사회활동이 없는 비율이 정신분열병군이 가장 높았고(72.3%), 알콜장애군(32.0%), 정동장애군(20.7%)의 순이었다. 4) 국내 의료보험 및 사회복지시설 이용 자료 등을 토대로 본 조사 결과를 적용한 결과 국내중증 만성 정신질환자의 수는 약 8만 7천명으로 추산되었다. Objectives: The purpose of this study was to estimate the number of serious and persistent mentally ill patients in Korea. Methods : Study populations were recruited from medical insurance data of two district areas ; one rural and the other urban areas. Subject were all mentally ill who had ever visited any hospital in 1993 and were diagnosed as having psychosis, personality disorder and drug abuse. We conducted a home visiting survey applying semi-structured diagnostic interview, assessing the level of social adjustment with Strauss-Carpenter Scale, and past psychiatric history by the trained researchers, in October and November,1994. Results : According to diagnostic assessment schizophrenic patients constituted the major portion(61.1%) of study subjects. The distribution of occupational functions and social contacts was variable according to diagnosis. Most schizophrenic patients were unemployed or worked less than 6 months in the previous year(67.2%), and showed poor social contact(72.3%). But affective disorder patients were relatively independent in job maintenance and social relationship. Alcoholic patients lay between those of schizophrenic and affective disorder groups. It was estimated that about 87,000 adult Koreans were suffering from chronic mental disorders which seriously interfere with their daily life. Conclusions : Serious and persistent mentally ill patients were common in Korea. Community support program should be provided for them.

A Study on the Verification Way to Solve Troubles of GOOSE Communication in the Digital Substation

Nam-Ho Lee,Nam-Dae Kim,Yu-Yeong Park 한국조명·전기설비학회 2020 조명·전기설비학회논문지 Vol.34 No.7

The conventional analog type substation is replaced to digital substation using computer based operation system and IEDs (Intelligent Electronic Device) based on IEC 61850. IEC 61850, international standard of substation automation system, describes MMS and GOOSE as the communication services of the digital substation, and most of utilities want to verify the new digital interfaces of the substation automation system and they think that IEC 61850 conformance test from UCA IUG does not assure completed system operation at real site because this test is only the functional test. KEPCO Research institute has been performing technical support as a home doctor on the digital substations. A GOOSE trouble was found at “GOZAN” S/S one of the KEPCO digital substations. This paper presents the specific way to find the reason of the GOOSE trouble found in the substation and introduces how to solve the issue.

Thermomechanical and optical properties of molecularly controlled polyimides derived from ester derivatives

Nam, Ki-Ho,Kim, Hyeonil,Choi, Hoi Kil,Yeo, Hyeonuk,Goh, Munju,Yu, Jaesang,Hahn, Jae Ryang,Han, Haksoo,Ku, Bon-Cheol,You, Nam-Ho Elsevier 2017 Polymer Vol.108 No.-

<P><B>Abstract</B></P> <P>New diamines for high-performance poly(ester imide)s (PEsIs) containing dimethyl groups at the <I>ortho</I>-position of amino groups and ester derivatives have been developed to improve optical transparency and glass transition temperature (T<SUB>g</SUB>) while maintaining a low coefficient of thermal expansion (CTE). Four kinds of PEsIs derived from bis(4-amino-3,5-dimethylphenyl) terephthalate (BADMT) and aromatic dianhydrides such as 1,2,4,5-benzenetetracarboxylic dianhydride (PMDA), 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), 4,4’-oxydiphthalic anhydride (ODPA), and 4,4'-(hexafluoroisopropylidene)diphthalic (6FDA) were synthesized via a two-step polycondensation. All PEsIs exhibited outstanding properties, such as light color, a good transmittance of >90% at 550 nm, high T<SUB>g</SUB> above 289 °C and 5% weight loss temperature (483–511 °C), and low CTE (11–68 ppm/°C). The effect of the substituent on molecular packing and properties, including optical and thermomechanical properties for the resulting PEsIs were examined in detail. The temperature-dependent CTE of the PEsIs was determined using molecular dynamics (MD) simulation. The molecular orbital (MO) calculation models support the discussions on the electronic substituent effect of the PEsI main chains. Our molecular architecture and systematic property studies with MD and MO promote a better understanding of the polyimides.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New diamines for high-performance poly(ester imide)s (PEsIs) have been developed. </LI> <LI> The polymer films exhibited a good transmittance of >90% at 550 nm, high T<SUB>g</SUB> above 289 °C and 5% weight loss temperature (483–511 °C), and low CTE (11–68 ppm/°C). </LI> <LI> Molecular dynamics (MD) simulation was performed to study the CTE of PEsIs and the agreement between measured and simulated results was acceptable. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Low CTE and transparent poly(ester imide)s (PEsIs) containing dimethyl groups at the <I>ortho</I>-position of amino groups was newly synthesized.</P> <P>[DISPLAY OMISSION]</P>

Input sequencing and scheduling for a reconfigurable manufacturing system with a limited number of fixtures

Yu, Jae-Min,Doh, Hyoung-Ho,Kim, Ji-Su,Kwon, Yong-Ju,Lee, Dong-Ho,Nam, Sung-Ho Springer-Verlag 2013 INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TE Vol.67 No.1

Laparoscopy Assisted versus Open Distal Gastrectomy with D2 Lymph Node Dissection for Advanced Gastric Cancer: Design and Rationale of a Phase II Randomized Controlled Multicenter Trial (COACT 1001)

Nam, Byung Ho,Kim, Young-Woo,Reim, Daniel,Eom, Bang Wool,Yu, Wan Sik,Park, Young Kyu,Ryu, Keun Won,Lee, Young Joon,Yoon, Hong Man,Lee, Jun Ho,Jeong, Oh,Jeong, Sang Ho,Lee, Sang Eok,Lee, Sang Ho,Yoon, The Korean Gastric Cancer Association 2013 Journal of gastric cancer Vol.13 No.3

Purpose: Laparoscopy-assisted distal gastrectomy for early gastric cancer has gained acceptance and popularity worldwide. However, laparoscopy-assisted distal gastrectomy for advanced gastric cancer is still controversial. Therefore, we propose this prospective randomized controlled multi-center trial in order to evaluate the safety and feasibility of laparoscopy assisted D2-gastrectomy for advanced stage gastric cancer. Materials and Methods: Patients undergoing distal gastrectomy for advanced gastric cancer staged cT2/3/4 cN0/1/2/3a cM0 by endoscopy and computed tomography are eligible for enrollment after giving their informed consent. Patients will be randomized either to laparoscopyassisted distal gastrectomy or open distal gastrectomy. Sample size calculation revealed that 102 patients are to be included per treatment arm. The primary endpoint is the non-compliance rate of D2 dissection; relevant secondary endpoints are three-year disease free survival, surgical and postoperative complications, hospital stay and unanimity rate of D2 dissection evaluated by reviewing the intraoperative video documentation. Discussion: Oncologic safety is the major concern regarding laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Therefore, the non-compliance rate of clearing the N2 area was chosen as the most important parameter for the technical feasibility of the laparoscopic procedure. Furthermore, surgical quality will be carefully reviewed, that is, three independent experts will review the video records and score with a check list. For a long-term result, disease free survival is considered a secondary endpoint for this trial. This study will offer promising evidence of the feasibility and safety of Laparoscopy-assisted distal gastrectomy for advanced gastric cancer. Trial Registration: NCT01088204 (international), NCCCTS-09-448 (Korea).

Planar n-Si/PEDOT:PSS hybrid heterojunction solar cells utilizing functionalized carbon nanoparticles synthesized via simple pyrolysis route

Nam, Yoon-Ho,Kim, Dong-Hyung,Shinde, Sambhaji S,Song, Jae-Won,Park, Min-Joon,Yu, Jin-Young,Lee, Jung-Ho IOP 2017 Nanotechnology Vol.28 No.47

<P>Herein, we present a facile and simple strategy for <I>in situ</I> synthesis of functionalized carbon nanoparticles (CNPs) via direct pyrolysis of ethylenediaminetetraacetic acid (EDTA) on silicon surface. The CNPs were incorporated in hybrid planar n-Si and poly(3,4-etyhlenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) solar cells to improve device performance. We demonstrate that the CNPs-incorporated devices showed increased electrical conductivity (reduced series resistance) and minority carrier lifetime (better charge carrier collection) than those of the cells without CNPs due to the existence of electrically conductive <I>sp</I> <SUP>2</SUP>-hybridized carbon at the heterojunction interfaces. With an optimal concentration of CNPs, the hybrid solar cells exhibited power conversion efficiency up to 11.95%, with an open-circuit voltage of 614 mV, short-circuit current density of 26.34 mA cm<SUP>−2</SUP>, and fill factor of 73.93%. These results indicate that our approach is promising for the development of highly efficient organic–inorganic hybrid solar cells.</P>

Synergistic toughening of polymer nanocomposites by hydrogen-bond assisted three-dimensional network of functionalized graphene oxide and carbon nanotubes

Nam, Ki-Ho,Yu, Jaesang,You, Nam-Ho,Han, Haksoo,Ku, Bon-Cheol Elsevier 2017 Composites science and technology Vol.149 No.-

<P><B>Abstract</B></P> <P>We report a facile method to enhance mechanical properties of polymer nanocomposites using three-dimensional (3D) network structures of functionalized graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs) in a polymer matrix. The GO and MWCNTs were functionalized using Fisher indole and diazonium-salt reactions to produce pyridine (Py) moiety on the GO and MWCNTs. The functionalized GO (Py-RGO) and MWCNT (Py-MWCNT) nanocomposites exhibited hydrogen-bond assisted 3D network structures in a polyimide (PI) matrix. By incorporating 1 wt% of carbon materials (0.9 wt% Py-RGO and 0.1 wt% Py-MWCNTs) in a PI, the tensile strength and modulus of the ternary nanocomposites reached 581 MPa and 31 GPa, respectively, which was an enhancement of 221% and 312% compared with pristine PI. The fracture energy of the PI/Py-RGO/Py-MWCNT nanocomposites improved 200% and approached 29.7 MJ m<SUP>−3</SUP>. The formation of the 3D network structure of the functionalized carbon nanomaterials is considered to significantly affect load transfer of nanofillers in the polymer matrix, and produce high performance polymer nanocomposites.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>