• Korean Journal of Anesthesiology
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• 제71권6호
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• pp.430-439
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• 2018

In infants and small children, ultrasound (US) guidance provides ample anatomical information to perform neuraxial blocks. We can measure the distance from the skin to the epidural space in the US image and can refer to it during needle insertion. We may also visualize the needle or a catheter during real-time US-guided epidural catheterization. In cases where direct needle or catheter visualization is difficult, US allows predicting successful puncture and catheterization using surrogate markers, such as dura mater displacement, epidural space widening due to drug injection, or mass movement of the drug within the caudal space. Although many experienced anesthesiologists still prefer to use conventional techniques, prospective randomized controlled trials using US guidance are providing increasing evidence of its advantages. The use of US-guided regional block will gradually become widespread in infants and children.

• 한국표면공학회지
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• 제55권6호
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• pp.417-424
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• 2022

This research develops an easy-to-use, environmentally friendly method for fabricating functional 1050 aluminum alloy surfaces with excellent corrosion resistance. Functional aluminum surfaces with various nanostructures are fabricated by controlling the experimental conditions of anodizing process. The experiment used a multi-step anodizing process that alternates between two different anodizing modes, mild anodizing (MA) and hard anodizing (HA), together with a pore-widening (PW) process. Among them, the nanostructured surface with a small solid fraction shows superhydrophobicity with a contact angle of more than 170° after water-repellent coating. In addition, the surface with superhydrophobicity is difficult for corrosive substances to penetrate, so the corrosion resistance is greatly improved.

• 대한후두음성언어의학회지
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• 제31권2호
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• pp.56-60
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• 2020

Vocal fold injections are usually performed with a patient wake in an office under local anesthesia. For comfortable and safe office-based procedures, thorough anesthesia and premedication should be provided to the following three regions; nasal cavity, oropharynx, and larynx. Topical lidocaine is most widely used anesthetics on office based procedure. Lidocaine has a low to intermediate potency, 45 minutes to 60 minutes' duration of action, and onset of sufficient anesthesia within 90 seconds of topical administration. Tetracaine, prilocaine, ropivacaine, and bupivacaine also have been used in the office-based procedures. Nasal decongestant, oxymetazoline, is also used for widening nasal cavity by constriction of nasal mucosa. The amount of topical and local anesthetics used in vocal fold injection rarely exceeds toxic doses. The physician should know proper anesthesia techniques and must be familiar with the safe dose and complication of all anesthetics used.

• 항공우주시스템공학회지
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• 제16권5호
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• pp.57-61
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• 2022

항공기 및 우주 구조물에 갈륨비소 기판은 다양하게 적용된다. 본 연구에서 온도 제어기술을 활용하여 수치해석을 통해 4인치 이상의 대구경 갈륨비소 잉곳의 성장에 관한 기술을 제시하였다. 본 연구를 통해 온도 시뮬레이션 기술을 기반으로 다양한 온도 변화와 주위 환경의 변화에 따른 제작 기술을 확보하였다. 잉곳 기술 개발을 통하여 편차가 작은 특성 결과를 도출하여 향후 적용 가능성을 최대화 하였다.

• KDI Journal of Economic Policy
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• 제45권1호
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• pp.1-32
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• 2023

Growth of the Korean economy has been sluggish, and this situation is more pronounced in the service sector. We argue that capital misallocation, especially in the service sector, could contribute to this slowdown. Utilizing firm and sectoral level data, first we assess the rising dispersion of the marginal revenue product of capital (MRPK) driven by the service sector. This could represent a widening misallocation of capital. Furthermore, a panel regression shows that within-sector misallocations at the sectoral level are closely correlated with the lower growth rate of sectoral real value added. Again, this is mainly observed in the service sector, but not in the manufacturing sector. Misallocations of other resources, labor and the intermediate inputs do not stand out.

• International Journal of Computer Science & Network Security
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• 제22권12호
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• pp.178-184
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• 2022

Renewable energy sources based on solar radiation, wind energy, geothermal energy, and biomass energy have now reached the level of industrial application. A new way to generate electricity using low-potential heat is to install a hydro-steam turbine. In hydro-steam turbines, hot water is supplied directly to turbine rotor nozzles without prior separation into steam and water in separators, which significantly increases the efficiency of hot water energy use. Such turbines are suggested to be used as autonomous energy sources in geothermal heating systems, heating water boilers and cooling systems of chemical reactors, metallurgical furnaces, etc. The authors conclude that the installation of hydro-steam turbines in heating plants and process boiler plants can also be effective if the used exhaust steam-water mixture at the turbine outlet is used to heat the network water or as return water.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.699-704
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• 2005

Normally, monetary penalties for breach of agreement will be stipulated in the contract. The contractor parties, who fail to fulfill the agreement, are required to pay the other parties a certain amount or proportion of money as a fine. However, it is worth our study - whether or not the scope of monetary penalty implementation and bases for determination of a fine will cover the losses of social and administrative costs incurred by the interruption of the contract. This research is about the best timing for government to cancel the freeway repair work contracts. Under the goal of the maximum social welfare, the limitation of government spending for the social and administrative costs invoked by interruption of contracts will have to be considered to attain the best timing of contracts' suspension or deferment. According to the factors of social and administrative costs, the best time point is calculated to reduce the loss of the aforesaid costs, which can also be used as theoretical basis for the future road-widening construction at home.

• ETRI Journal
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• 제44권1호
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• pp.147-154
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• 2022

We demonstrate a new double-layer structure for stretchable interconnects, where the top surface of a serpentine polyimide support is coated with a thin eutectic gallium-indium liquid metal layer. Because the liquid metal layer is constantly fixed on the solid serpentine body in this liquid-on-solid structure, the overall stretching is accomplished by widening the solid frame itself, with little variation in the total length and cross-sectional area of the current path. Therefore, we can achieve both invariant resistance and infinite fatigue life by combining the stretchable configuration of the underlying body with the freely deformable nature of the top liquid conductor. Further, we fabricated various types of double-layer interconnects as narrow as 10 ㎛ using the roll-painting and lift-off patterning technique based on conventional photolithography and quantitatively validated their beneficial properties. The new interconnecting structure is expected to be widely used in applications requiring high-performance and high-density stretchable circuits owing to its superior reliability and capability to be monolithically integrated with thin-film devices.

• Asia pacific journal of information systems
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• 제30권2호
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• pp.353-373
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• 2020

This paper tries to closely look at compliance knowledge relatedness and IT relatedness based on Tanriverdi's 'relatedness' concept. Also, this paper's main focus lies on how knowledge relatedness and IT relatedness influence compliance performance through compliance knowledge exploitation. The present study conducted a full-scale survey and finalized questionnaire was sent to compliance managers of 187 Korean multi-business firms. This study found (1) the impact of compliance knowledge relatedness on compliance performance, (2) the mediating role of knowledge exploitation on the relationship between compliance knowledge relatedness and compliance performance, and (3) the interaction effect of IT relatedness and compliance knowledge relatedness on knowledge exploitation. This paper contributes to both academic and business world by widening applicability of theories and providing guidelines conducive to improved compliance performance of corporations.

• Clinics in Shoulder and Elbow
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• 제14권1호
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• pp.59-66
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• 2011

목적: 견쇄관절의 손상이나 원위 쇄골 골절의 치료에 대해서는 많은 연구가 있으나, 견쇄관절 손상을 동반한 원위 쇄골 골절의 치료에 대해서는 알려진 바가 적다. 저자들은 견쇄관절의 손상을 동반한 원위 쇄골 골절의 수술적 치료 및 결과, 예후를 평가하고자 한다. 대상 및 방법: 견쇄관절의 손상을 동반한 쇄골 외측단에서 2.5 cm 내를 침범한 원위 쇄골 골절로 수술적 치료를 받은 21명 (21예)의 환자를 대상으로 후향적 연구를 시행하였다. 단순 방사선 사진과 CT상 원위 쇄골의 골절선이 견쇄관절로 연장 (5예)되어 있거나, 7 mm 이상의 견쇄관절의 이개 (separation)가 있는 관절내 골절 (9예), 또는 건측과 비교해서 50% 이상 원위 쇄골의 상방전위가 있는 관절내 골절 (7예)을 견쇄관절의 손상이 있는 경우로 분류하였다. Craig 분류상 III형이 16예, V형이 5예였다. 금속판 (9예), 소형나사 (1예), K 강선 및 긴장대 강선 (10예) 및 경 견쇄관절 K 강선 (1예)을 사용하여 골절을 고정하였다. 건측에 비해 100%이상 원위 쇄골의 상방전위가 있었던 1예 및 골편이 작아 고정력이 약하다고 판단된 1예에서 경 견쇄관절(transarticular AC joint) K 강선 고정을 추가적으로 실시하였다. 견봉 쇄골 인대 또는 오구 쇄골 인대의 봉합이나 재건술은 시행하지 않았다. 결과: 21예 중 20예에서 골유합을 얻었으며 골유합까지의 기간은 평균 8.4주이었다. 최종 추시시 5예에서 견쇄관절의 외상성 관절염이 관찰되었고, 4예에서 견쇄관절의 이개가, 2예에서 건측과 비교하여 50% 이하의 상방전위가 남아 있었으나 견쇄관절의 이개 및 상방전위가 술전보다 증가된 예는 없었다. Kona 등의 기준에 따른 기능적 평가상 19예에서 우수, I예에서 양호, 1예에서 보통의 결과를 얻었다. 견쇄관절 손상의 분류에 따른 UCLA 점수는 I형에서 32.6점, II형에서 34점, III형에서 34.1점이었다. 술전 견쇄관절 손상 종류, 술후 잔여 관절의 이개 및 전위, 외상성 관절염의 유무와 임상 결과간에 유의한 연관성은 관찰되지 않았다 (p>0.05). 합병증으로는 K 강선 및 긴장대 강선 고정술로 고정한 1예에서 불유합이 관찰되어 술후 3개월 금속판 고정술 및 골이식술을 시행하여 골유합을 얻었으며, 금속판 고정술을 시행한 1예에서 추시 관찰 중 내고 정물의 이완이 있었으나 추가적인 치료 없이 골절이 유합되었다. 결론: 견쇄관절로 연장된 골절이 있거나 관절내 골절이 있으면서 견쇄관절 간격이 7 mm 이상 벌어진 경우 또는 정상측과 비교하여 50% 이상 원위 쇄골의 상방전위가 있는 견쇄관절의 손상이 동반된 경우라도 원위 쇄골의 정확한 정복과 견고한 내고정을 통해 만족할 만한 결과를 얻었다. 수술 전 견쇄관절의 손상 종류 및 수술 후 경도의 외상성 관절염이나 이개, 상방전위와 임상적 기능 사이에 유의한 연관성은 없었다.