• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.664-667
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• 2010

Solid rocket propulsion systems are generally used for tactical missiles due to the structural and operational simplicity. Nevertheless, various kinds of design factors including outer diameter, length, weight, loading efficiency of propellant grain effects to thrust performance. Dual thrust is beneficial to range extension and terminal velocity increasement. But loading efficiency becomes low in case to obtain dual thrust performance by burning surface control. So, It is predicted to be reasonable to obtain dual thrust performance with high/low burning rate propellants. This study is on internal ballistic analysis and ground test to confirm dual thrust performance.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.68-76
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• 1984

The study was conducted to investigate an optimum growing condition for various sizes of seedlings of rice for mechanical transplantation under different sowing rates, different levels of fertilizers, different sowing dates and g rowing days. The plant height, leaf number and dry weight of seedlings increased as the sowing rate decreased and amount of fertilizer applied were increased. Also those seedling characters increased as the rice planted late and the total growing periods increased. The factors affected seedling chracters were ordered as following-sowing times>growing days>sowing rate>fertilizer levels. 200 gr. of seeds per box and 4 gr. of fertilizers were optimum for young seedling growth, when sown early. For medium size of seed ling growth, 50 grams and 100 to 125 grams of rice seemed to be adequate for 25 days old and 35 days old seedling, respectively. However, the 45 days old seedling grew too mach and were not suitable for mechanical transplantation. When planted late, similar results were obtained with more differences among treatments. In other words, the suitable plant density was obtained when 100 gr. of seeds were planted per box. Middle class of seedlings were obtained when 100 to 150 gr. of rice were planted per box and grown for 25 days. The seedlings from the box with 100 to 150 gr. of rice per box were over grown and ratio of suitable seedling was also low if they were grown over 35 days.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.481-487
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• 1998

The surgical management of acute type B dissection is controversial. The complexity of the repair usually requires a period of aortic cross-clamping exceeding 30 minutes, which can cause ischemic injury of the spinal cord. Several forms of distal perfusion have been considered for use to prevent this injury. To determine the safety and efficacy of a graft replacement with cardiopulmonary bypass in reparing acute dissection of descending thoracic aorta, we retrospectively reviewed our surgical experience treating 8 patients who had aortic dissection secondary to atherosclerosis, trauma, and carcinoma invasion. Cardiopulmonary bypass was performed with two aortic cannulas for simultaneous perfusion of the upper and lower body and one venous cannula for draining venous blood from the right atrium or inferior vena cava. Although aortic cross-clamp time was relatively long (average, 117.8 minutes; range, 47 to 180 minutes) in all cases, there was no neurologic deficit immediately after graft replacement for the aortic lesion. Two patients(25%) of relatively old age died on the postoperative 31st and 41st days, respectively, because of delayed postoperative complications, such as pulmonary abscess and adult respiratory distress syndrome. Although any of several maneuvers may be appropriate in managing dissection of the descending aorta, graft replacement with cardiopulmonary bypass during aortic cross-clamping may be a safe and effective method for the treatment of acute dissection of the descending thoracic aorta.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.5 s.45
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• pp.1-10
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• 2005

This study proposes a fatigue reliability evaluation procedure for steel-composite high-speed railway bridge based on dynamic analysis and investigates the effectiveness of Tuned Mass Damper(TMD) in terms of the extension of fatigue life of the bridge. For the fatigue reliability evaluation, the limit state is determined using S-N curve and linear fatigue-damage accumulation. Dynamic analyses are peformed repeatedly to consider the uncertainties of train-velocity and damping ratio of the bridge. The distribution of random variables related to fatigue damage for the intended service life is then statistically estimated from analytical results. Finally, the fatigue reliability indices are obtained by means of the Advanced First-Order Second-Moment (AFOSM) method. Through numerical simulation of a steel-composite bridge of 40m span, the effectiveness of TMD on fatigue life of the bridge is examined and the results are presented.

• Journal of the Korea Concrete Institute
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• v.18 no.1 s.91
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• pp.73-82
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• 2006

Nowadays, the general stripping work of form has brought some problems; increase of total constructing cost resulted from the man-dependent form work procedure and environmental issues by wasting the debonded form. In this study, to effectively reduce unnecessary cost and resolve the environmental problems caused by these kinds of reason, a permanent form method using stainless steel fiber was introduced then its material and structural characteristics were evaluated. In the case of material characteristic, the permanent form had a good ductile behavior in the result of flexural test of the permanent form panel and pull-out test of insert bolt which is installed in the permanent form and perfect bonding capacity with a field concrete. In the case of structural characteristic, compressive and tensile behavior of the permanent form was evaluated. It also showed a good structural behavior in the view of load-deflection relationship, crack patterns and additional strengthening effect.

• Journal of the Korean Geographical Society
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• v.1
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• pp.67-82
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• 1963

This paper examined the settlement and evolution of the Namdo Food Festival holding in Nakan folk village since 1994. The Namdo Food Festival is a representative event tourism in Chonnam which beautifully displays Nakan eup-sung's folk landscape and Namdo's traditional food, a prime tourist resource. Since 1994, the Namdo Food Festival has steadily evoloved in the scale aspects of the program budget, and the number of visitors participating in festiva. In addition, the period of the food festival was fixed for a week, early in October. The majority of visitors to the festival was from Kwangju. Moreover, visitors from other provinces have steadily increased, in particular visitors from Yeongnam province such as Pusas and Kyeongnam provinces have increased since 1996. In order to settle down and develop the Namdo Food Festival, the followings should be done change of the ownership from public to private sector, training of professional entertainers, development of programs which can reinforce historical aspects and placeness of Nakan folk village, adoption of management technoques for the local economic activities, and extension of linkage with tourists places around Nakan folk village, reflection of tourists interests and needs through a continuoua tourist's behaviour analysis.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.1
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• pp.108-112
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• 2000

Hypophosphatemic rickets is lack of reponse to physiologic doses of vitamin D, different from the vitamin D-dependent rickets. It is inherited in an X-linked dominant fashion. The prime features of this disorder are lowered serum phosphate levels, elevated serum alkaline phosphatase and normal serum calcium levels. The dental manifestation often include apical radiolucencies, abscess and fistulas of clinically sound teeth. Dental radiographs show ricketic bone trabeculations, abscent or abnormal lamina dura and abnormal cementum. This case which was diagnosed to hypophosphatemic rickets, showed multiple spontaneous periapical abscess and gingival fistula enlarged pulp chambers, extension of the pulp horns into the cusp tips and delayed eruption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.7380-7384
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• 2014

Evacuation fire doors were manufactured by applying phosphorescent paint to the whole fire door whose performance was already recognized, and applying heat sensitive paint around the grip. The facility was improved by the evacuation and safety functions on the fire door, which has been used as only a fire facility, and the fire door is also used as an evacuation facility. The brilliance of the evacuation safety fire door manufactured in this study passed the brilliance test of Korea Fire Institute with a performance more than the brilliance (7mcd after 60 minutes) of the existing inducement sign. During a fire, the visible area is larger than the evacuation door inducement, etc. and light preventive status in the lower part of the fire door was observed during the descent of smoke. Therefore, it is considered to extend the evacuation effective time of evacuators. In heat sensitive paint applied around the grip, a color change is observed on the fire door when approaching a certain temperature ($70^{\circ}C$). Therefore, the first disaster that evacuators can encounter on the grip of a fire door during a fire can be prevented and should be helpful in recognizing the backfiring possibility and preventing safety accidents for firefighters who must enter a fire space.

• The Inventors News
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• no.55
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• pp.1-16
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• 2007

선진국가 선도하는 창의적 여성경제리더 양성하자/발명지도사.시제품제작지원 시행/발행인 칼럼/특허심사처리 세계에서 가장 빠르다/글로벌 기업, 한국 특허청에 심사의뢰 쇄도/국유특허권 온라인 전자계약 시행/특허기술, "기술경매" 로 산다/여성발명인 거유 활동 영역 넓어/감귤와인 특허획득 이어 독일 등 해외 수출 기대/미더덕 냉동 않고도 장기 보관/특허민원서식 대폭 감축/특허청, 개도국 지원사업 대폭 확대/기상청, 날씨예보기술로 특허 받아/우리나라 국제특허출원 수준 세계 6위/건강관련 브랜드 상표출원 증가/친환경수로관 '도룡용 살린다'/고등학교에 첫 발명창작과 개설/욕조, 웰빙 휴식공간으로 자리매김/가습기, 공기정화.탈취.방향 등 다기능화/패치제 특허출원 해마다 증가/일 특허청, 분할출원기간 30일 연장/중 법원, 비아그라 특허군 인정/국내 제약사 유유 "미머크사 특허 침해" 주장/삼성전자, 지난해 미 특허 2천4백53건으로 2위/기업심볼마크는 단순, 상표는 길어져/LG전자 "대우일렉이 드럼세탁기 특허권 침해했다"/유.무선 통합 '원폰 서비스' 기술 개발/암환자 울린 과대광고제품 1백억원대 판매 적발/맥도날드 '해피밀' 광고 퇴출/세원셀론텍, 콜라겐 원천기술 특허/역사 속의 발명품/하루 10분 발명교실/특허Q&A/'S&D Trecap' 황지경 대표/경기도, 여성분야 소상공인창업자금 신설/특허청, 세계지식재산기구(WIPO) 진출확대/아이디어 착상 및 발명 기법/여성발명 활성화만이 국가경쟁력 키우는 첩경/히로자키의 광엽수 진액/해외 네티즌 인기 화제의 발명품들/여성기업 생산제품 MAS시 적격성 평가 면제/특허청, 시작품제작지원 5천만원까지 확대/지난해 짝파라치에게 3억2천3백만원 포상금 지급/입체방송 분야 특허출원 봇물/트랜스지방 퇴출 시민단체 '토트랜스 클럽' 출현/한국여성발명협회 회원사 발명품 가이드/

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.80-86
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• 2011

When a tooth adjacent to implant has coronal damages caused by severe dental caries or fracture, the clinical crown lengthening by forced eruption makes it possible to get esthetic restoration due to the prevention of alveolar crestal bone resorption and loss of interdental papilla. A 54-years-old male patient wanted prosthetic treatment because his anterior 3 unit bridges had fallen out. A right maxillary central incisor showed mild dental caries but a right maxillary canine lost most clinical crowns. Forced eruption combined with a gingival fiberotomy of a right maxillary canine was performed for 1 month after the dental implant had been simultaneously placed with bone grafts on a right maxillary lateral incisor. About 5 months after implant placement, 2nd surgical operation was performed. The provisional restorations were adjusted to make esthetic gingival contour for 8 weeks. The porcelain fused gold restorations were fabricated and set. The patient was satisfied with the final restorations in esthetic and functional aspect.