• 펄프종이기술
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• 제39권2호
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• pp.1-8
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• 2007

To examine the feasibility of dry forming technology for papermaking, a dry forming mold (DFM) was developed and evaluated. Main fanning section of DFM was a cylindrical tube, and at the top of the mold a stirring equipment was placed to disperse dry fibers. These fibers were screened using a hole type screen plate placed just under the stirring equipment and dropped freely on the fanning wire located 0.9 m below of the screen plate to form a dry fiber pad. The vertical and horizontal velocity of air flow in the forming cylinder were evaluated and analyzed to find the most effective method of air flow control in the cylinder. Humidification and pressing conditions to obtain a decent dry fanned papers were examined. Results showed dry fanned papers can be prepared with this dry forming mold. And this mold can be used to examine the effect of the papermaking process factors including pressing pressure, drying temperature, humidification on sheet quality of dry formed papers.

• ETRI Journal
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• 제44권5호
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• pp.715-732
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• 2022

Despite the successful launch of Advanced Television Systems Committee (ATSC) 3.0 broadcasting worldwide, broadcasters are facing obstacles in constructing void-less large-scale single-frequency networks (SFNs). The bottleneck is the absence of decent on-channel repeater (OCR) solutions necessary for SFNs. In the real world, OCRs suffer from the maleficent feedback interference (FI) problem, which overwhelms the desired input signal. Moreover, the undesired multipaths between studio-linked transmitters and the OCR deteriorate the forward signals' quality as well. These problems crucially restrict the feasibility of conventional OCR systems, arousing the strong need for cost-worthy advanced OCR solutions. This paper presents an ATSC 3.0-specific solution of advanced OCR that solves the FI problem and refines the input signal. To this end, the FI canceler and channel equalizer functionalities are carefully implemented into the OCR system. The presented OCR system is designed to be fully compliant with the ATSC 3.0 specifications and performs a fast and efficient signal processing by exploiting the specific frame structure. The real product of ATSC 3.0 OCR is fabricated as well, and its feasibility is verified via field and laboratory experiments. The implemented solution is installed at a commercial on-air site and shown to provide substantial coverage gain in practice.

• 디자인학연구
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• 제6권1호
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• pp.73-86
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• 1993

The development of Korean textile industry has continued for the early industrialization. But a change in situation of circumstances, textile industry undergoes hard times. To overcome the barrier, therefore, technical development and design innovation are needed to make high value added product. This paper try to put to practical use of the silk weighting process technique(WPT). First, we investigate the technical trend of WPT to summarize the theory, and examine the feasibility of technical development. Second, the application of Graft process to silk textile is examined to know whether it is possible as an practical use. Next, we present the practical way of WPT using MAA monomer through experiment. The results are as follow. 1) Considering the lack of silk yarn. Graft process is appropriate new technique to make the value added product, and fine quality. 2) Studing textile goods, it need inter-displlinary co-work not only fiber engineering scope because textile goods is closely related with fashion industry. 3) MAA monomer used in this paper is more excellent then other monomer because it has good weighting effect and does not harm to the nature of textile. 4) MAA WPT is good for silk textiles of ladies jacket and neck-tie.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 학술대회 논문집 전문대학교육위원
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• pp.118-121
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• 2005

In this paper, it has been proposed the simultaneous controller of electronic ballast and PFC(power factor corrector) for fluorescent lamp by one chip micro-controller. Boost DC-DC converter is adopted for PFC, and half bridge inverter for electronic ballast. It controls, simultaneously and independently, the boost DC-DC converter and the half bridge inverter. As electronic ballast and PFC are controlled by one chip micro-controller, it is possible to achieve the cheaper controller for fluorescent lamp. Experimental result has shown the feasibility of the proposed simultaneous controller of PFC and electronic ballast.

• KIEE International Transactions on Power Engineering
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• 제5A권3호
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• pp.221-227
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• 2005

This paper evaluates minimum and maximum power exchange considering economic and technical characteristics between Russia and ROK. First, we evaluate minimum power exchange to assure the economic feasibility by comparison with the total cost and benefit of the interconnected line. For evaluating maximum exchange power, system constraints are considered, which are examined through load flow and dynamic analysis by using the PSS/E program. As a result of these evaluations, we suggest the reasonable range of power exchange between ROK and Russia considering economic and technical constraints with the interconnection scenario that power system interconnection between ROK and Russia will be realized in the year 2010.

• Clinical Endoscopy
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• 제57권2호
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• pp.263-267
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• 2024

Technical failure of endoscopic ultrasound-guided gallbladder drainage (EUS-GBD) is often attributed to device failure. To rectify this problem, we developed a single-pigtail plastic stent (SPPS) for EUS-GBD. We retrospectively reviewed the cases of four patients who underwent EUS-GBD for acute cholecystitis. To prepare the SPPS, a 7.5-Fr endoscopic nasobiliary drainage tube was cut to an appropriate length. The use of SPPS during EUS-GBD was successful from both technical and clinical standpoints. The SPPS spontaneously detached 57 days after the procedure in patient 4 and 412 days after the procedure in patient 1. Patient 1 developed cholecystitis after 426 days and was managed with antibiotics. The other three patients did not develop any complications after surgery. In conclusion, we designed a new SPPS dedicated to EUS-GBD and established its technical feasibility and clinical effectiveness.

• 농업과학연구
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• 제48권4호
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• pp.855-863
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• 2021

The purpose of this study is to suggest an improvement plan for the National Technical Qualification Practical Evaluation focusing on National Competency Standards. First, in order to strengthen practical techniques such as field abilities and expertise, practical evaluation methods were applied to the National Competency Standards, referring to a learning module focused on field performance. Second, an expert advisory committee in the field of organic agriculture was utilized to compare, analyze, and match the competency unit and competency unit elements of the National Competency Standards with the national technical qualification examination standards in field of organic agriculture. In addition, in order to identify work in progress in the industrial field, share professional practice skills, and analyze facilities and equipment, we visited an organic agriculture industry site. Through this, a practical evaluation exam was developed. Subsequently, in order to confirm the adequacy of the developed exam, the pilot test assessment was conducted for those majoring in organic agriculture. Finally, as a feasibility study, a survey was conducted. Based on the results, greater technical job competency in the field of organic agriculture will contribute to strengthening knowledge in this field by suggesting an improvement plan for the national technical qualifications practical evaluation method in the field of organic agriculture.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.347-352
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• 2001

도심재개발 사업은 도시의 쇠퇴해진 기능을 회복하고 토지이용을 높이기 위하여 시행되는 사업이나 다양한 참여주체와 이 주체들간의 상이한 기대목표, 도심지라는 지리적 위치로 인한 고지가, 고 밀도 개발요구, 장기간의 사업기간, 막대한 자금의 소요 등은 타당성 분석을 어렵고 복잡하게 만든다. 이러한 도심재개발사업의 특수성 때문에 타당성 분석에서 다루어야 한 요인들이 다양해지고 신뢰 있는 분석이 요구되나, 타당성분석의 어려움으로 인하여 도심재개발 사업의 미 착수, 사업중단, 사업지연의 상황을 발생시키고 있다. 따라서 본 연구에서는 도심재개발 사업의 타당성 분석에서 반드시 다루어야 할 경제/재무 관련요인, 법적/제도적 관련요인, 시장관련요인, 기술적 관련요인, 갈등관계 관련요인 등5개 범주로 분류되는 총45개의 요인을 문헌고찰, 사례연구, 실무전문가 면담 등을 동하여 정립한 후 관련전문가의 설문조사 분석을 통하여 주요요인을 제시함으로써 도심재개발 사업의 타당성 분석에 도움을 주고자 한다.

• Clinical Endoscopy
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• 제55권6호
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• pp.793-800
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• 2022

Background/Aims: Fully covered self-expanding metal stents (FCSEMSs) are a relatively novel option for treating painful main pancreatic duct refractory strictures in patients with chronic pancreatitis. Herein, we aimed to assess the efficacy, feasibility, and safety of FCSEMSs in this patient group. Methods: This prospective single-center study included patients who underwent endoscopic retrograde pancreatography with FCSEMS placement. The primary endpoints were the technical and clinical success rates. A reduction in visual analog scale pain score of >50% compared with that before stent placement was defined as clinical success. Secondary endpoints were resolution of pancreatic strictures on fluoroscopy during endoscopic retrograde pancreatography and the development of stent-related adverse events. Results: Thirty-six patients were included in the analysis. The technical success rate was 100% (n=36) and the clinical success rate was 86.1% (n=31). There was a significant increase in stricture diameter from 1.7 mm to 3.5 mm (p<0.001) after stent removal. The mean visual analog scale pain score showed statistically significant improvement. At 19 months of follow-up, 55.6% of the patients were asymptomatic. Stent migration (16.7%), intolerable abdominal pain (8.3%), development of de novo strictures (8.3%), and mild pancreatitis (2.8%) were the most common adverse events. Conclusions: FCSEMS placement showed good technical and clinical success rates for achieving pain relief in patients with refractory main pancreatic duct strictures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.632-634
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• 2005

Korea takes part in overseas business by use of accumulated advanced technology through construction of the worlds first 765kV double circuit transmission system designed with pure local technology. 'Development Study on the Power System Network Analysis in Myanmar' was received in the year 2001 and was completed in the year 2002. The following project,'Feasibility Study and Basic Designs for the 500kV Transmission System in Myanmar' has been in progress since January, 2004. With regards to this project the master plan for the Myanmar long term power system was submitted in January 2005, and now the basic designs for the 500kV transmission system construction are in progress. Technical data for the design of the transmission line is calculated using a very complex numerical formula that is almost impossible to be completed by hand. So the transmission technical calculation system was developed to calculate and support Myanmar technical data for the design of transmission line with respect to factors such as wind prossure load, tower design data conductor design data and insulator design data on the basis of weather conditions for the Myamar transmission line design area of the Myanmar 500kV trans- mission line construction basic design.