부산항에서의 중국 환적화물 물동량 분석

정재헌,강개선 한국국제상학회 2013 國際商學 Vol.28 No.1

This research tries to analyze all Chinese transshipment cargo in Busan port on the basis of grouping Chinese transshipment cargo by origin/destination ports and by import/export types. We found out the trend of the throughput and important ports and regions from which they efficiently attract transshipment cargo for the Busan port. Analysis implies that transshipment cargo from the north Chinese ports will continue to increase even though Chinese government invests in large scale for the development of the port and container cargo continues to increase. This is because international shipping companies have not been used the ports as expected by chinese government mainly due to the bad weather. South Chinese port cargo will grow much from the vast hinterland with high potential of economic growth. Busan port has been had small throughput of transshipment for the ports because of long distance from them but has been had notable transshipment cargo from the ports in the view of growth rate and stability. We selected important 14 ports on the basis of the transshipment cargo volume and trend characteristics so that we suggested different marketing strategies for each port on the same basis. Finally, we used regressions to forecast future 5 year Chinese transshipment cargo in Busan port and estimated the throughput will be around 3 million TEU in 2015.

폐페인트 재활용공정 및 장치개발 연구

정재헌,한대상,조창제,이종무,장상목 동아대학교 공과대학부설 생산기술연구소 1998 生産技術硏究所硏究論文集 Vol.3 No.2

In this study, the process and equipment to recycle wastepaint were designed and development. The characteristic of this recycling process is to improve the recycling efficiency by dividing the previous recycling process into two processes, liquid-phase process and powder-phase process, with the hardness of wastepaint. As the result of this study, we confirm that this process may be helpful to recycle wastepaint.

III. 총의치 인공치아의 배열

정재헌,송미령 대한치과의사협회 1993 대한치과의사협회지 Vol.31 No.1

사회적 네트워크 분석을 이용한 전자산업 클러스터 연구

정재헌 한국콘텐츠학회 2019 한국콘텐츠학회논문지 Vol.19 No.5

본 연구는 한국기업정보(주)에서 제공받은 2015년도의 5만 여개의 최신 기업정보를 활용하여 전자업체를 중심으로 거래 네트워크를 생성하여, 사회네트워크 분석을 포함한 새로운 분석을 시도하였다. 그 결과 97개의 10개 이상 기업으로 이루어진 클러스터들이 발견되었고, 전자산업 매출의 90% 이상을 차지하는 13개의 클러스터들을 주목하게 되었다. 사회네트워크 분석에서의 클러스터들은 소속 기업들이 해당 클러스터 안에서 거래를 완결하는 특성을 가지고 있다. 13개 클러스터들을 보면, 매출액이 많은 상위 5개 클러스터에 전자매출의 83%가 집중되어 있으며, 일부 예외를 제외하고는 각각의 클러스터들은 특정업체가 매출의 대부분을 차지한다. 그렇지만 이들 이외에도 후방생산연관효과가 특별히 높은 업체들도 발견하였으며, 중소기업에 미치는 영향력이 특히 큰 전자 업체들도 눈에 뜨인다. 후방생산연관효과가 높은 업체들은 성장 정책적인 측면에서, 그리고 중소기업에 영향력을 많이 미치는 전자업체들은 중소기업 육성 정책적인 측면에서 중시되어야 할 것이다. 그리고 작은 클러스터들의 합인 마지막 기업군은 매출 대비 고용이 매우 높은 특성을 지닌다는 사실도 발견하였다. 이 기업군에 높은 생산연관효과를 보이는 기업군과 전자업체들이 발견되었으며, 이들은 고용정책적 측면에서 중시될 필요가 있다. 거래를 중계하는 네트워크 특성인 사이중심성이 매출과 비례하지 않게 특별히 높은 클러스터들도 발견하였다. 사이 중심성이 높은 이들 클러스터들은 기술 발전의 가능성이 큰 기업 그룹들이기에 주목할 필요가 있다. We tried new analysis including social network analysis(SNA) on the transaction network centered on electronic companies using more than 50 thousand company transaction data obtained from Korean enterprise data (KED) for the year of 2015. We found 97 clusters having more than 10 firms and remarkable 13 clusters having more than 90% sales of the electronic industry in Korea. Clusters are the groups of companies having most of their transactions in the clusters they belong to. We found 5 clusters have 83% of sales in the electronic industry. Most of clusters have main single firms having most of the sales in each clusters except a few clusters. However, we found a few firms to have high rear production linkage effect and found the firms with high linkage effect specially for the small and medium size enterprise (SME). The companies with high production linkage (specially on SMEs) should be managed in terms of (SME) growth policy. The last firm group consisting of the small clusters with less than 10 firms has high employment coefficients. The clusters or company having high production linkage effect on this last firm group should be noted in the terms of employment policy. We also note that there exist the firms with the high value of betweenness coefficients meaning high potential of technology development. They should be managed carefully in terms of technology development policy.

아스팔트 혼합물의 인공노화 방안 연구

정재헌,조병진,박남원,김광우 한국도로학회 2007 한국도로학회논문집 Vol.9 No.4

This study was carried out for developing artificial short-term aging (SA) and long-term aging (LA) methods of asphalt mixtures in which the aging level is properly matched with those of RTFO and PAV aged binders, respectively. The specimens were made of the short-term aged loose asphalt mixture which was kept in a convection oven at 154℃ for 2 hours and were aged at 110oC for 24, 48, 72 and 96 hours for SA. Large molecular size (LMS) were measured using GPC after SA and LA to evaluate aging extents of each mixture with aging time. It is shown that the LMS was increased with aging time increment, and that from the LMS(%) change ratio, it was possible to suggest an appropriate artificial aging time which is corresponding level of aging with RTFO and PAV. It was found that SA was somewhat strong and LA for 48 hours at 110oC would be appropriate if sort-term aging is properly controlled.

RF 마그네트론 스퍼터링을 이용하여 온도별로 증착한 CIGS 박막의 미세구조 및 화학 조성 분석

정재헌,조상현,송풍근 한국진공학회 2012 한국진공학회 학술발표회초록집 Vol.2012 No.8

Feedforward compensation of back electromotive force for suppressing rotational motion errors in a magnetically levitated system

정재헌,안다훈,김기현,최영만,김명현,이학준,박재현,김현준,류지흔,김효영,권대갑 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.10

The magnetically levitated system, so called maglev system, has been researched and developed with the purpose of vacuum compatibility in the semiconductor industry. In the maglev system, the back electromotive force is inevitably generated when the system moves. The back electromotive force causes force/moment disturbances. Especially, the moment disturbances have negative effect on controlling the rotational motions (θ x , θ y , θ z ) whose control bandwidth is low. Therefore, the back electromotive force causes rotational motion errors. The rotational motion errors should be suppressed since they prevent high speed motion of the maglev system due to the rotational motion allowance of sensors. The rotational motion errors are suppressed by compensating the back electromotive force. In this paper, the back electromotive force, the cause of the rotational motion errors, is mathematically found in terms of the mover velocity and element of force-current matrix. A maglev system without the compensation was simulated and the rotational motion errors due to back electromotive force were found. Then, a feedforward compensated system using a mathematically modeled back electromotive force was simulated. It was verified that the feedforward compensation method with the modeled equation could be useful for suppressing rotational motion errors.

[Free Paper] Critical limb ischemia 환자에 영향을 미치는 Angiosome effect

정재헌,장정환 대한외과학회 2011 대한외과학회 학술대회 초록집 Vol.2011 No.11

P-92 The Role of PAK1/CREB axis in Carcinogenesis of Squamous Cell Lung Cancer

정재헌,김윤성,윤성훈 대한결핵 및 호흡기학회 2017 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.124 No.-

Background: The p21-activated Ser/Thr kinase 1 (PAK1) kinase has an essential role in tumorigenesis in many cancers, but whether PAK1 expression correlates with NSCLC tumorigenesis and its mechanism is still poorly understood. We hypothesized that PAK1 could modulate the cyclic AMP response element binding (CREB) protein expression and its activity, which have a central role in lung carcinogenesis as a regulatory factor in NSCLC. Methods: Clinical data were retrospectively reviewed in 60 patients with squamous cell lung cancer from the tissue microarray. Western blotting, immunohistochemical analysis, and TUNEL were performed to study for the expression and interaction of PAK1 and CREB. Results: We showed that in squamous lung cancer tissues, PAK1 was upregulated (3-fold to 4-fold, P=0.015), tyrosine phosphorylated (3-fold, P<0.01), and translocated to the nucleus. PAK1 siRNA-transfected downregulation induced apoptosis in squamous carcinoma cells by cleavage and activation of downstream effector caspases. Consistent with the results from Western blotting, apoptotic cell death was detected by TUNEL assay. Overexpression of PAK1 was positively correlated with CREB activity (r=0.69, P<0.05). Notably, PAK1 blockade did not change the level of CREB but modify CREB activity (P<0.005). We performed Western blotting from over-expression plasmid transfected cells and found that PAK1 phosphorylates CREB at Ser133. Conclusion: Our findings offered evidence that PAK1 phosphorylates CREB in lung squamous carcinomas, with implications for regulation of PAK1 as a potential therapeutic target of squamous lung cancer treatment.

지방정부 해안방제능력의 개선방안에 관한 연구 - 중앙정부의 지원방안을 중심으로 -

정재헌,김상구 해양환경안전학회 2017 海洋環境安全學會誌 Vol.23 No.4

The importance of marine pollution prevention is increasing day by day both at home and overseas. Against this context, this study proposes policy directions to forge an improved system of coastal control for local governments. I have analyzed the coastal pollution response capacity of local governments to find out how the central government can better support these efforts to reinforce capacity. For the purposes of this research, I carried out a number of case studies on large-scale marine pollution accidents that occurred at home and abroad. According to the results, I identified the implications of the coastal pollution response capacity of local governments and suggested several alternatives such as construction of step by step response system, strengthening education and training, part of human network activation, establishment of grounds for securing response resources, and establishment of dedicated department to prepare for potential future marine pollution accidents. However, as little research has been done on the coastal pollution response capacity of local governments, this work may be regarded as an experimental study to help facilitate follow-up research in the future. 본 연구는 국내‧외적으로 해양오염사고 예방에 관한 관심과 중요성이 날로 증대되는 가운데, 지방정부 중심의 해안방제체계를 구축하기 위한 정책방향 설계에 그 목적이 있다. 따라서 지방정부의 해안방제능력을 진단하고 해안방제 실행력 강화를 위해 필요한 중앙정부의 정책적 지원방안이 무엇인지를 밝혀보고자 하였다. 이러한 연구목적을 달성하기 위하여 국내외에서 일어났던 대규모 해양오염사고 사례분석을 통해 지방정부가 해안방제를 어떻게 수행했는지를 분석하고, 해안방제에 관한 지방정부의 문제점을 찾아내어, 향후 발생가능한 대형 해양오염사고의 해안방제 대비에 필요한 사항을 중심으로 단계별 대응체제 구축, 교육훈련 강화, 인적 네트워크 활성화, 방제자원 확보근거 마련, 전담부서 신설 등 지방정부의 해안방제능력 개선방안을 제시하였다. 그러나 아직까지 지방정부의 해안방제관리능력에 관한 연구가 일천한 상황에서 본 연구는 시험적 연구라고 판단되며, 따라서 본 연구의 결과는 시험적 연구로서 다음의 후속 연구에 큰 도움이 되었으면 한다.