• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1214-1218
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• 2005

As demands for precision parts are increased, existing methods to fabricate them such as MEMS, LIGA technology have the technical limitations like high precision, high functionality and ultra miniaturization. A micro-stereolithography technology based on $DMD^{TM}$(Digital Micromirror Device) can meet these demands. In this technology, STL file is the standard format as the same of conventional rapid prototyping system, and 3D part is fabricated by stacking layers that are sliced as 2D section from STL file. Whereas in conventional method, the resin surface is cured as scanning laser beam spot according to the section shape, but in this research, we use integral process which enables to cure the resin surface at one time. In this paper, we deal with the dynamic pattern generation and $DMD^{TM}$ operation to fabricate micro structures. Firstly, we address effective slicing method of STL file, conversion to bitmap, and dynamic pattern generation. Secondly, we suggest $DMD^{TM}$ operation and optimal support manufacturing for $DMD^{TM}$ mounting. Thirdly, we examine the problems on continuous stacking layers, and their improvements in software aspects.

• 자원리싸이클링
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• 제13권3호
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• pp.50-57
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• 2004

알루미늄 폐드로스는 알루미늄 용해업체에서 발생되는 주요 폐기물 중 하나인데, 주요 성분은 알루미나이며 상당량의 금속 알루미늄이 잔류한다. 알루미늄 폐드로스 내에 잔류하는 금속 알루미늄을 수산화나트륨 용액으로 침출, 분리시켜서 수산화알루미늄으로 제조하는 과정에서 침출잔사가 발생되는데, 침출 후 여과잔사의 주요 성분은 알루미나이다. 본 연구에서는 이 침출잔사를 세척, 건조, 배소하여 알루미나질 캐스타블 내화물과 같은 세라믹 원료로 재활용하는 연구를 수행하였으며, 상용화를 위한 파일롯트 플랜트시험을 수행하였다. 실증 생산라인은 년 간 1,000톤의 폐드로스를 처리하여 약 700톤의 세라믹 원료를 생산할 수 있는 규모이다. 생산라인의 시운전 결과, 개발 기술의 상용화 적용 가능성을 확인하였으며 상용화를 위해서 건조기의 개선과 Na, Fe등 불순 성분들이 시료에 유입되는 것을 줄여야 하는 문제점들을 파악할 수 있었다.

• The Korean Journal of Pain
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• 제30권3호
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• pp.220-228
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• 2017

Background: The transforaminal (TF) epidural steroid injection (ESI) is suggested as more effective than the interlaminar (IL) route due to higher delivery of medication at the anterior epidural space. However, serious complications such as spinal cord injury and permanent neural injury have been reported. The purpose of this study is to evaluate and compare the clinical effectiveness, technical ease, and safety of the TF and parasagittal IL (PIL) ESI. Methods: A total of 72 patients were randomized to either the PIL group (n = 41) or the TF group (n = 31) under fluoroscopic guidance. Patients were evaluated for effective pain relief by the numerical rating scale (NRS) and Oswestry Disability Index (ODI) (%) before and 2 weeks after the ESI. The presence of concordant paresthesia, anterior epidural spread, total procedure time, and exposed radiation dose were also evaluated. Results: Both the PIL and TF approach produced similar clinically significant improvements in pain and level of disability. Among the 72 patients, 27 PIL (66%) and 20 TF (64%) patients showed concordant paresthesia while 14 (34%) and 11 (36%) patients in the same respective order showed disconcordant or no paresthesia. Radiation dose and total procedure time required were compared; the PIL group showed a significantly lower radiation dose ($30.2{\pm}12$ vs. $80.8{\pm}26.8$ [$Cgy/cm^2$]) and shorter procedure time ($96.2{\pm}31$ vs. $141.6{\pm}30$ seconds). Conclusions: ESI under fluoroscopic guidance with PIL or TF approach were effective in reducing the NRS and ODI. PIL ESI was a technically easier and simple method compared to TF ESI.

• 한국대기환경학회지
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• 제33권6호
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• pp.533-543
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• 2017

As the public interest in environmental issues increased, the "Act On The Integrated Control Of Pollutant-Discharging Facility" was enacted. Through the integrated environmental pollution prevention act in which 19 industries with large environmental impacts are sequentially applied, pollutants can be managed in a medium-integrated manner and integrated permission of the business unit is possible and BAT can be applied to enable a scientific and proactive environmental management system. In order to facilitate the implementation of integrated environmental pollution prevention act with these advantages, the BAT BREF should be published, modified and revised every 5 years considering the level of scientific development. This study reviewed the issues to be considered in applying BAT and the types of BAT and focused on presenting improvements and development direction when revising and supplementing the standards in the future based on these contents. For this purpose, when revising the standards, it will be necessary to reflect on the domestic situation, to expand the TWG(Technical Working Group) of small-scale workplace experts, and to exchange opinions with business places that have similar processes for each waste type through a systematic total inspection. In addition to these methods, by establishing a resident participation system through information disclosure, it is expected to be used as a guideline for environmental management of business places not subject to integrated permission of less than 3 types as well as those subject to integrated permission.

• 한국산학기술학회논문지
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• 제11권8호
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• pp.2840-2852
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• 2010

남한에 입국하는 북한이탈주민의 수는 1990년대 중반부터 지속적으로 증가하여 최근에는 그 수가 2만여명에 이르고 있으며, 앞으로도 계속 증가할 것으로 예상된다. 그동안 정부에서는 북한이탈주민들이 우리사회의 일원으로 자립 자활의지를 갖고 안정적으로 정착할 수 있도록 다양한 제도를 발전시켜 왔다. 이 연구에서는 북한이탈주민이 남한사회에서 경제적으로 적응할 수 있는 실제적인 도움이 될 수 있도록 북한에서 취득한 자격을 국가기술자격으로 인정하는 제도를 개선하고자 하였다. 이 연구를 위하여 자격시행 전문가, 교육훈련 전문가, 자격 연구자 및 정부기관 전문가 70명을 대상으로 델파이 조사를 실시하였다. 그 결과에 따라 현행 북한자격 인정 제도를 보완하는 측면에서 자격인정 절차에 소관부서의 역할을 강화하고, 자격인정 방법에 경력을 추가하는 방향으로 개선안을 마련하였다.

• 자원리싸이클링
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• 제27권5호
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• pp.38-48
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• 2018

심층처리혼합공법은 다양한 지반조건에서 개량을 위해 사용되고 있으며 그 기술개발은 개량을 위한 고화재의 성능향상과 고화재와 토사의 혼합효율 향상을 바탕으로 이루어지고 있다. 본 연구에서는 베트남 지역에서 발생하는 순환유동층 발전 플라이애시를 사용한 고화재로 실트질 점토지반을 1내지 3 MPa의 강도를 갖도록 개량하는 것이 가능하였으며, 혼합효율을 향상시킨 개량비트를 사용하여 시험시공을 진행한 결과 기존비트 대비 균질한 구근을 형성하여 강도의 표준편차를 1.0 MPa 이상에서 0.322 MPa로 줄일 수 있었다.

• 대한기관식도과학회지
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• 제8권2호
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• pp.36-42
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• 2002

Aspirated and ingested foreign bodies continue to present challenges to otolaryngologists. The major discussions were the accurate diagnosis and speedy, safe removal of foreign body. Many diagnostic tools have been tried and removal of foreign bodies has been facilitated by technical improvements with rod lens telescope, video endoscope, flexible fiberoendoscope and safer anesthesia. In spite of these advances, more than 3000 children's death occur per year in the world because of foreign bodies and untold number of parients survive with variable sequelae. In these study, 59 consecutive cases of children and adults with tracheobronchial foreign bodies were reviewed from 1992 to 2001. We studied the history, symptoms, ausculatory radiologic, bronchoscopic finding and post operative complications. 71% (42 cases in 59 cases) of patients had foreign body aspiration history or choking crisis. In 64% (38cases) cough was observed. 81% (48cases) had abnormal finding in chest auscultation and 78% in chest X-ray. Computed tomography was done in 12 cases, all were founded foreign body shadow. Main site of foreign body was right main bronchus (41%, 24cases) and most frequent foreign body was peanut (36% , 21cases) . 4 experienced ICU(intensive care unit) care. 2 cases were failed to remove foreign. In these cases 1 cases was improved by steroid therapy and physical therapy and the other was treated with thoracotomy. We concluded the morbidity and motality were much correlated with speedy decision making and experienced skill of operator.

• 환경정책연구
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• 제3권2호
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• pp.31-57
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• 2004

Attempts were made to compare and analyze the policies of the United States, the United Kingdom, the Netherlands, Germany and Denmark concerning Korea's major problems associated with legal liability of the contaminated sites. These countries were chosen from a feasible preliminary analysis of 18 countries of the EU and the U. S. The major problems were revealed based on the analysis of Korean legacy and legislation, which are summarized as follows i) lack of clear detailed technical and legal guidance to determine the responsible party or parties of contaminated sites, ii) no distinction between the strict and non strict legal liability of innocent land owners, iii) no clearly set limit on retroactive legal liability. Comparison of the policies of countries chosen suggested improvements regarding these major problems as follows: i) activating national and international research on soil contamination prevention policy, ii) arranging distinct legal regulation between strict and non strict liability criteria, iii) establishing the limits on innocent and non strict liability, iv) establishing methodology and process of legal liability distribution and compensation, and v) establishing a legal process to redeem any benefit derived from remediation of contaminated sites with the public budget. Our policy suggestions above are not yet conclusive due to a lack of policy implementation simulation. Additional research is needed on aspects of social, economic and long term effects of the proposed policy directions. Nevertheless, application of the policy suggestions of this research would increase the efficacy of Korean policy regarding the survey and remediation of the potentially contaminated sites.

• Journal of Radiation Protection and Research
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• 제20권1호
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• pp.37-44
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• 1995

과학기술처의 개인방사선피폭선량평가에 관한 기술기준이 제정된 이후 TLD에 의한 개인피폭선량평가 기술은 많은 발전이 있었으나, 우리나라 대부분의 방사선관련 산업체에서 방사선 피폭관리용으로 사용되고 있는 필름배지의 정확한 선량평가기술을 확보하기 위한 연구는 아직도 미진한 상태이다. 따라서 본 연구에서는 ISO 표준방사선장을 이용하여 i) 실험식에 의한 방법, ii) Degree-of-fit에 의한 방법, 그리고 ) Matrix에 의한 방법으로 필름배지에 의한 선량평가 알고리즘개발방법을 제시하였다. 이러한 방법들에 의한 계산값은 조사량과 ANSI N13.11에서 제시하고 있는 성능지수 이내에서 잘 일치하였으며, 이는 X, ${\gamma}$ 혹은 혼합방사선장에서 선량평가에 유용하게 혼용될 수 있을 것이다.

• 제어로봇시스템학회논문지
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• 제18권5호
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• pp.426-432
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• 2012

The positions of vessels in JTIDS where each vessel broadcasts its position, can be found using the relative navigation method. Besides positioning, the relative navigation could be adopted for identification friend or foe, tracking targets, monitoring battle field and etc. In this paper, we have explained the fundamental operation and technical structure for the relative navigation and implemented the simulation platform to evaluate the basic function and performance of the system in arbitrary environment. Using platform, the availability of relative navigation within the group network and the characteristic of the algorithm for position prediction was verified. Based on the simulation result, it was verified that EKF based navigation algorithm could produce great initial error and need quite convergence time. To improve the performance, we proposed a new navigation algorithm which uses the minimum norm estimation algorithm until the EKF converges. The simulation results reveal the relative navigation can be effectively used in the formation flight and collision avoidance system.