• 전자통신동향분석
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• 제35권4호
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• pp.1-10
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• 2020

Since the 1960s, semiconductor packaging technology has developed into electrical joining techniques using lead frames or C4 bumps using tin-lead solder compositions based on traditional reflow processes. To meet the demands of a highly integrated semiconductor device, high reliability, high productivity, and an eco-friendly simplified process, packaging technology was required to use new materials and processes such as lead-free solder, epoxy-based non cleaning interconnection material, and laser based high-speed processes. For next generation semiconductor packaging, the study status of two epoxy-based interconnection materials such as fluxing and hybrid underfills along with a laser-assisted bonding process were introduced for fine pitch semiconductor applications. The fluxing underfill is a solvent-free and non-washing epoxy-based material, which combines the underfill role and fluxing function of the Surface Mounting Technology (SMT) process. The hybrid underfill is a mixture of the above fluxing underfill and lead-free solder powder. For low-heat-resistant substrate applications such as polyethylene terephthalate (PET) and high productivity, laser-assisted bonding technology is introduced with two epoxy-based underfill materials. Fluxing and hybrid underfills as next-generation semiconductor packaging materials along with laser-assisted bonding as a new process are expected to play an active role in next-generation large displays and Augmented Reality (AR) and Virtual Reality (VR) markets.

• 한국전문물리치료학회지
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• 제27권4호
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• pp.250-256
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• 2020

Background: Unstable surface-based core training can significantly enhance core strength, but no studies have compared the effects of balance pad- and sling-assisted exercises. Objects: To study the effects of unstable surface-based balance pad- and sling-assisted core strength exercises on muscle activity. Methods: Twenty male students aged 20-25 years participated in this study. The effects of three types of core strength exercises, performed with a sling or balance pad, on the activities of three muscles, i.e., the right musculus obliquus externus abdominis (EO), right erector spinae (ES), and right gluteus maximus (GM), were examined. Results: 1) In the glute bridge exercise, the percentage of maximum voluntary contraction of the EO, ES, and GM were significantly different between the balance pad- and sling-assisted exercises. The relative contribution of the ES and GM activities to all muscle activity were not significantly different between the two training types, whereas that for EO showed a significant difference. 2) There was no significant difference in the percentage value of maximum voluntary contraction (%MVC) among the EO, ES, and GM during the "leg-lifting with flat support" exercise, and there were no significant difference in the relative contributions between the two training types. 3) In the "side bridge leg separation exercise", the %MVC of the ES, EO, and GM were significantly different between the two training types. Conclusion: Sling training for core muscles was generally better than balance pad assist training. The majority of physiotherapy patients require core training. Our results could guide physiotherapists in the choice of targeted exercises for these patients.

• Archives of Plastic Surgery
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• 제38권1호
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• pp.121-126
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• 2011

Purpose: Vaccum-assisted closure (VAC) has rapidly evolved into a widely accepted treatment of contaminated wounds, envenomations, infiltrations, and wound complications. This results in a sealed, moist environment where tissue is given the opportunity to survive as edema is removed and perfusion is increased. Many plastic surgeons now place a VAC device directly over the fasciotomy site at the time of the initial procedure. Large amounts of the fluid are withdrawn, and fasciotomies can be closed primarily sooner. This study was designed to observe the effect of VAC in preventing complications in snake bitten hands. Methods: In our study of three cases of snake bite, three of them underwent the VAC treatment & fasciotomy of the wound in the hand. This cases, the posterior compartment of the hand was bitten for a few days, releasing incisions were made of the posterior hand and 125 mmHg of continuous vacuum was applied to fasciomy incision site and the biting wound. The dressings were changed three times per week. Results: Our study examining the effects of applied vacuum in preventing snake bite wounds showed that the incidence of tissue necrosis and compartment syndrome was significantly lower for vacuum-treated wounds than for conservative wounds. Serum myoglobin, CK-MB, and CPK levels measured after fasciotomy incision were significantly decreased. We obtained satisfactory results from early dorsal fasciotomy, drainage of the edema with the VAC system, and then primary closure. The postoperative course was uneventful. Conclusion: Envenomation is a term implying that sufficient venom has been introduced into the body to cause either local signs at the site of the bite and/or systemic signs. Use of the vacuum-assisted closure device in snake bite can result in a decreased rate of tissue necrosis, lymphatic fluid collection, hemolytic fluid collection, and edema. Early fasciotomy of the dorsal hand and VAC apply is the alternative treatment of the snake bite.

• 공업화학
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• 제24권5호
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• pp.507-512
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• 2013

페롭스카이트형 산화물을 마이크로파 공정으로 합성하여 XRD, XPS, BET 및 $H_2-TPR$ 등에 의해 특성분석을 하였고, 벤젠의 연소반응에서의 활성을 조사하였다. 대부분의 촉매들은 페롭스카이트 결정구조를 잘 가지고 있었으며 21 nm 에서 35 nm의 크기를 나타내었다. $LaMnO_3$ 촉매가 가장 높은 활성을 보여주었고 $250^{\circ}C$에서 거의 100%의 전환율을 나타내었으며, 마이크로파 공정으로 제조한 촉매가 기존의 졸-겔법으로 제조한 촉매에 비해 높은 활성을 보여주었다. 또한 소성온도가 증가함에 따라 연소반응의 활성이 증가하였다. 모든 촉매들의 산화환원 성질을 측정한 수소 승온환원 실험 결과는 벤젠의 연소반응의 순서와 잘 일치하였다.

• 대한관절경학회지
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• 제11권2호
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• pp.134-138
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• 2007

Brodie 농양은 빈도가 흔하지 않고, 독성이 적은 원인균에 의해 발생하는 아급성 혹은 만성 골수염의 국소형으로 소아나 청소년의 하지 장골 특히 경골의 골간단과 골단 부위에 호발하나 성인에서도 발생할 수 있다. 수술적 치료시 병변의 위치가 근위 경골 골간단 후방에 위치한 경우 개방적 소파술로는 병소 접근이 어렵고 신경 혈관 손상 및 주위 조직 오염의 위험성이 있다. 본원 정형외과에서 48세 남자에서 발생한 경골 근위부 골간단 후방부의 Brodie 농양을 전방 십자 인대 재건술시 사용하는 표적 기구(Rigid fix system, Mitek, Johnson & Johnson, Norwood, MA)를 이용하여 병소에 손쉽고 정확하게 삽입구를 만들어 내시경 시야 하에서 염증 및 육아 조직을 제거하여 치료한 경험이 있어 이를 문헌 고찰과 함께 보고하고자 한다.

• 농촌계획
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• 제22권1호
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• pp.57-67
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• 2016

The purpose of this study was to review of animal-assisted therapy. Method: Animal-assisted therapies (AATs) in domestic and international studies (68 cases) were analyzed by searching databases, KERIS & KISS, and the Pub MED(NCBI). Result: In AATs, a few animals were used for the various disease or disorder. Dog centered therapies were most common.. AATs were used in the various disorder and disease. For the psychological effect, majority of the outcome variables were depression and anxiety. For the physical effect, the most outcome variables were blood pressure, heart rate, and stress hormone. However, These results show that AATs were confined to specific areas such as sensation-centered therapies. Conclusion: AATs had positive effects both in physical and psychological factors even if the study areas have not been applied to the various condition. The further research is needed to identify scientific grounds for the effects of the interventions through various therapies.

• Advances in pediatric surgery
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• 제17권1호
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• pp.45-50
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• 2011

Meckel's diverticulum (MD) has various clinical presentations and due to the limitation of imaging studies, pre-operative diagnosis is a challenge in pediatric patients. Recently, laparoscopic exploration has been suggested as a favorable method for the diagnosis and treatment of complicated MD. We investigated the results of laparoscopic-assisted surgery compared with open technique. We retrospectively studied patients who underwent resection of complicated MD at our institute from 1997 to 2010 and compared 11 treated by laparoscopic-assisted diverticulectomy (LD) with 11 treated by open diverticulectomy (OD) for complicated MD. Operation time was not significantly different in the two groups. Hospital stay and time to diet were not significantly different. Two patients were re-admitted due to mechanical ileus in the LD group. None of patients in either group needed re-operation. Considering the possibility of false-positive results with imaging studies and the cosmetic benefit, laparoscopic-assisted surgery is a safe and effective treatment modality to diagnose and treat complicated Meckel's diverticulum.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.3045-3050
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• 2013

Purpose: Hepatic resection is arguably the preferred treatment for huge hepatocellular carcinoma (H-HCC). Estimating the remnant liver volume is therefore essential. This study aimed to evaluate the feasibility of using computer-assisted volumetric analysis for this purpose. Methods: The study involved 40 patients with H-HCC. Laboratory examinations were conducted, and a contrast CT-scan revealed that 30 cases out of the participating 40 had single-lesion tumors. The remaining 10 had less than three satellite tumors. With the consensus of the team, two physicians conducted computer-assisted 3D segmentation of the liver, tumor, and vessels in each case. Volume was automatically computed from each segmented/labeled anatomical field. To estimate the resection volume, virtual lobectomy was applied to the main tumor. A margin greater than 1 cm was applied to the satellite tumors. Resectability was predicted by computing a ratio of functional liver resection (R) as (Vresected-Vtumor)/(Vtotal-Vtumor) x 100%, applying a threshold of 50% and 60% for cirrhotic and non-cirrhotic cases, respectively. This estimation was then compared with surgical findings. Results: Out of the 22 patients who had undergone hepatectomies, only one had an R that exceeded the threshold. Among the remaining 18 patients with non-resectable H-HCC, 12 had Rs that exceeded the specified ratio and the remaining 6 had Rs that were < 50%. Four of the patients who had Rs less than 50% underwent incomplete surgery due to operative findings of more extensive satellite tumors, vascular invasion, or metastasis. The other two cases did not undergo surgery because of the high risk involved in removing the tumor. Overall, the ratio of functional liver resection for estimating resectability correlated well with the other surgical findings. Conclusion: Efficient pre-operative resectability assessment of H-HCC using computer-assisted volumetric analysis is feasible.

• Current Photovoltaic Research
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• 제1권2호
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• pp.103-108
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• 2013

Epitaxial growth of a high-quality thin Si film is essential for the application to low-cost thin-film Si solar cells. A polycrystalline Si film was grown on a $SiO_2$ substrate at $450^{\circ}C$ by a Al-assisted crystal growth process. For the purpose, a thin Al layer was deposited on the $SiO_2$ substrate for Al-assisted crystal growth. However, the epitaxial growth of Si film resulted in a rough surface with humps. Then, we introduced a thin amorphous Si seed layer on the Al film to minimize the initial roughness of Si film. With the help of the Si seed layer, the surface of the epitaxial Si film was smooth and the crystallinity of the Si film was much improved. The grain size of the $1.5-{\mu}m$-thick Si film was as large as 1 mm. The Al content in the Si film was 3.7% and the hole concentration was estimated to be $3{\times}10^{17}/cm^3$, which was one order of magnitude higher than desirable value for Si base layer. The results suggest that Al-doped Si layer could be use as a seed layer for additional epitaxial growth of intrinsic or boron-doped Si layer because the Al-doped Si layer has large grains.

• 분석과학
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• 제8권1호
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• pp.69-77
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• 1995

원자흡수용 gas-jet assisted RF 글로우 방전시스템을 제작하고 시료손실량과 원자흡광도에 미치는 실험변수들에 관한 연구를 수행하였다. 시료손실량과 흡광도는 방전전력, 압력 및 가스흐름에 큰 영향을 받았다. 원자흡광도와 시료손실량을 가스흐름이 600ml/min로 증가할 때 까지 계속 증가하였으며, 방전 압력은 3mbar에서 최대 흡광도를 나타내었다. 방전전력이 증가할수록 시료손실량과 흡광도는 증가하였으나 시스템의 안정도에 영향을 미치는 관계로 적당한 값의 선택이 필요하였다. 스테인리스 스틸 시료 중의 Ni과 황동시료 중의 Cr의 검량선을 작성한 결과 양호한 직선성이 얻어졌다.