• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.180-180
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• 2010

Thin film transistors (TFTs) based on oxide semiconductors have emerged as a promising technology, particularly for active-matrix TFT-based backplanes. Currently, an amorphous oxide semiconductor, such as InGaZnO, has been adopted as the channel layer due to its higher electron mobility. However, accurate and repeatable control of this complex material in mass production is not easy. Therefore, simpler polycrystalline materials, such as ZnO and $SnO_2$, remain possible candidates as the channel layer. Inparticular, ZnO-based TFTs have attracted considerable attention, because of their superior properties that include wide bandgap (3.37eV), transparency, and high field effect mobility when compared with conventional amorphous silicon and polycrystalline silicon TFTs. There are some technical challenges to overcome to achieve manufacturability of ZnO-based TFTs. One of the problems, the stability of ZnO-based TFTs, is as yet unsolved since ZnO-based TFTs usually contain defects in the ZnO channel layer and deep level defects in the channel/dielectric interface that cause problems in device operation. The quality of the interface between the channel and dielectric plays a crucial role in transistor performance, and several insulators have been reported that reduce the number of defects in the channel and the interfacial charge trap defects. Additionally, ZnO TFTs using a high quality interface fabricated by a two step atomic layer deposition (ALD) process showed improvement in device performance In this study, we report the fabrication of high performance ZnO TFTs with a $Si_3N_4$ gate insulator treated using plasma. The interface treatment using electron cyclotron resonance (ECR) $O_2$ plasma improves the interface quality by lowering the interface trap density. This process can be easily adapted for industrial applications because the device structure and fabrication process in this paper are compatible with those of a-Si TFTs.

• Nuclear Engineering and Technology
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• 제40권4호
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• pp.255-268
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• 2008

The greater demand for electricity and the available capacity within safety margins in some operating NPPs are prompting nuclear utilities to request license modification to enable operation at a higher power level, beyond their original license provisions. Such plant modifications require an in-depth safety analysis to evaluate the possible safety impact. The analysis must consider the thermo hydraulic, radiological and structural aspects, and the plant behavior, while taking into account the capability of the structures, systems and components, and the reactor protection and safeguard systems set points. The purpose of this paper is to introduce international experiences and approaches for implementation of power uprates related to the reactor thermal power of nuclear power plants. The paper is intended to give the reader a general overview of the major processes, work products, issues, challenges, events, and experiences in the power uprates program. The process of increasing the licensed power level of a nuclear power plants is called a power uprate. One way of increasing the thermal output from a reactor is to increase the amount of fissile material in use. It is also possible to increase the core power by increasing the performance of the high power bundles. Safety margins can be maintained by either using fuels with a higher performance, or through the use of improved methods of analysis to demonstrate that the required margins are retained even at the higher power levels. The paper will review all types of power uprates, from small to large, and across various reactor types, including light and heavy water, pressurized, and boiling water reactors. Generally, however, the content of the report focuses on power uprates of the stretch and extended type. The International Atomic Energy Agency (IAEA) is developing a technical guideline on power uprates and side effects of power uprates in nuclear power plants.

• Advances in aircraft and spacecraft science
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• 제4권3호
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• pp.281-296
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• 2017

The axial-injection end-burning hybrid rocket proposed twenty years ago by the authors recently recaptured the attention of researchers for its virtues such as no ${\zeta}$ (oxidizer to fuel mass ratio) shift during firing and good throttling characteristics. This paper is the first report verifying these virtues using a laboratory scale motor. There are several requirements for realizing this type of hybrid rocket: 1) high fuel filling rate for obtaining an optimal ${\zeta}$; 2) small port intervals for increasing port merging rate; 3) ports arrayed across the entire fuel section. Because these requirements could not be satisfied by common manufacturing methods, no previous researchers have conducted experiments with this kind of hybrid rocket. Recent advances in high accuracy 3D printing now allow for fuel to be produced that meets these three requirements. The fuel grains used in this study were produced by a high precision light polymerized 3D printer. Each grain consisted of an array of 0.3 mm diameter ports for a fuel filling rate of 98% .The authors conducted several firing tests with various oxidizer mass flow rates and chamber pressures, and analysed the results, including ${\zeta}$ history, using a new reconstruction technique. The results show that ${\zeta}$ remains almost constant throughout tests of varying oxidizer mass flow rates, and that regression rate in the axial direction is a nearly linear function of chamber pressure with a pressure exponent of 0.996.

• 가정∙방문간호학회지
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• 제28권3호
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• pp.317-328
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• 2021

Purpose: The purpose of this study is to provide patient-centered nursing by comparing the patient needs, patient satisfaction, and communication type of nurses for patients admitted to integrated nursing care service ward and general ward. Methods: Data were collected by self-report questionnaires between September 7 and October 9, 2021. Patients were patients recruited from a hospital in D city, 100 each from comprehensive nursing care service ward and general ward. The data were analyzed using descriptive statistics, 𝜒²-test, t-test, ANOVA, and Pearson's correlation. Results: There was no significant difference in patient needs between the patients of integrated nursing care service ward and the general ward (t=-1.12, p=.263). However, patient satisfaction was higher among the patients in integrated nursing care service ward than in the general ward (t=-3.55, p<.001). Pertaining to the communication type of nurses, the informational communication type (t=-4.02, p<.001) and the friendly communication type (t=-3.92, p<.001) were stronger in the integrated nursing care service ward than the general ward. It was, hence, confirmed that the educational requirements were positively correlated with patient satisfaction in the reliability domain and technical-professional domain, and that the nurse informational communication type and friendly communication type had a significantly positive correlation with patient satisfaction. Conclusion: The expansion of the integrated nursing care service ward may be considered in the future, with an informational and friendly communication method as an effective response that can be adapted in practice as a reflection the type of communication among nurses.

• 도시과학
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• 제8권1호
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• pp.33-44
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• 2019

The purpose of this study is to investigate the cause of repeated accidents through the investigation and analysis of the collapse cases of domestic earthquakes in order to prevent the earthquake disaster in the urban redevelopment and reconstruction. It is designed and constructed to draw out various problem factors and to find solutions to these problems. And the contents related to various laws and systems of the construction project management stage. Especially. In the management of the construction management centered on the safety management and quality control of the technical aspect design, supervision, construction phase through the cause of the accident and improvement measures based on the investigation report of the collapse of the construction site near Sangdo Kindergarten in Seoul. Supervisor. And constructors should be settled on the responsibility and responsibility of God. In order to achieve the purpose of the project, a system is established to link worker-centered occupational safety and health management with technology-based safety construction management, and analysis of how the quality control of the earthquake prevention affects safety construction management The purpose of this study is to prepare the optimum management plan of construction business.As a result of this study, it is aimed to accomplish the purpose of small scale redevelopment and reconstruction construction project by providing optimization method in the stage of construction project management in order to prevent collapse caused by differences in design,Is expected.

• 산업경영시스템학회지
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• 제42권3호
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• pp.193-205
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• 2019

Looking at recent safety accidents in buildings, most of them due to lack of FM expertise, and this is due to human resources. In each all industry areas, some companies are competitive, representational, and leading in the market through long-term expertise and research in their respective fields. In the field of FM industry, some companies offer core-competencies in internal and external innovative building management through competition with others. However, old custom and old management form still exist in the FM field. However, an old custom and old management system still exist in the FM field; it forces cost-cutting and caused by carelessness in technical development competitiveness and safety measures. The government control by safety inspection and facility inspection through legislation of building management, but the management is still weak as a side of in the facility management section due to inspect sth as a mere formality and submit a paper report. These facts exist different kind of usage of the building have a three-party encounter between a building owner, user, and FM enterprises. In this research identify survey, especially building owner (manager)'s choice perception priority for optional factors to choose FM enterprises. Based on this, FM enterprises will be forced to seek a new dimension for better building management. In this light, the purpose of the research is to shape changes in the FM market culture safely and providing better service in building management and understanding building owner's insight through this research's information.

• 지적과 국토정보
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• 제49권1호
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• pp.113-121
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• 2019

본 연구에서는 국내 외 4차 산업혁명 관련 기술 분야의 연구 동향을 분석하기 위해서 웹 기반의 텍스트 마이닝 및 소셜 네트워크 분석 기법을 이용하였다. 이를 위해 2014년 1월 1일부터 2018년 12월 31일까지 국내 외 4차 산업혁명 관련 기술에 대한 연구 논문 및 보고서의 제목 텍스트와 날짜를 대상으로 하여 텍스트 마이닝을 수행하였다. 이후 개념적인 차원에서의 키워드 간 연관성을 분석하기 위해서 형태소 분석을 통한 대표 키워드를 도출하였다. 이후 사회 연결망 분석을 활용하여 핵심 키워드 및 연관 키워드 등을 도출하였다. 그 결과, 우리나라에서는 4차 산업혁명 기술 관련 연구 개발 및 법 제도적 완화 등에 대한 초점을 두고 있다고 유추할 수 있다. 반면, 국외는 단위 서비스 형태로의 접근을 통해 도시에 대한 실질적 적용 기술에 초점을 두고 있음을 파악할 수 있었다.

• 산업융합연구
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• 제15권2호
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• pp.7-16
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• 2017

농업의 6차산업화는 농업의 융 복합을 통해 새로운 부가가치를 창출하며, 지역경제 활성화에 기여하는 등 농촌지역의 선순환 효과를 촉진시키고 있다. 이에 지역별 효율성 분석 및 효율성에 미치는 영향요인을 분석함으로써 국내 6차산업화 활성화를 위한 시사점을 제공하고자 한다. 본 연구의 분석 자료는 "2015년~2016년 농 식품 6차산업화 기초실태조사 연구" 보고서 자료를 활용하였다. 분석방법으로는 DEA 및 Tobit 검증을 통해서 분석을 실시하였다. 분석 결과는 다음과 같다. 첫째, 6차산업화는 소득증대 및 효율성 개선에 기여하고 있다. 두 번째, 연평균 농가 인구증가율, 2차산업 참여 비율은 부(-)의 관계가 있는 것으로 나타났다. 세 번째, 6차산업화 인지여부는 정(+)의 관계가 있는 것으로 나타났다. 본 연구 자료의 한계 및 정성적 요인, 외생변수 및 설명력 등의 한계가 있을 수 있지만, 지역별 6차산업화 효율성 제고를 위한 객관적인 시사점을 도출하였다는 점에서 의미가 있다.

• 건축역사연구
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• 제30권3호
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• pp.45-54
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• 2021

In 2020, Yi Hunwoo was discovered as one of the earliest modern architects in Korea. However, his personal life was yet mostly unknown, including the time of his death. The research team ('the team' hereafter) searched for the records of his personal life and professional career. First, his family genealogical chart revealed that he died in 1937. Having located and contacted Yi's direct descendents, the team was able to clarify his family background with the descendants' testimonies. They possess the photographs of him and his family members, including Yi's picture when he was a freshman at the Nagoya Higher Technical School in Japan. The team also identifies his birthplace and the location of his grave as Hadong, Gyeongsangnamdo, Korea. The team visited his project site in Jinju, Gyeonsangnamdo, Korea and obtained more detailed information about the Ilshin Girls' High School, which he designed in 1928. Gyohoan, the congregation records of Cheondogyo, one of the leading religions in Korea during Yi's times, confirmed that he was one of the congregation members. The field research also discovered the house he designed and built in his hometown of Hadong, probably the only surviving architectural project by him. This paper is to report the result of the research on Yi's life and career with the aim of providing materials for further studies in identifying and positioning him more properly in the early 20th century Korean architectural scene.

• Journal of Korean Neurosurgical Society
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• 제65권1호
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• pp.30-39
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• 2022

Objective : There are different types of cerebral vascular malformations. Pial arteriovenous fistulas (PAVFs) and dural arteriovenous fistulas (DAVFs) are two entities; they consist of one or more arterial connections to a single venous outlet without a true intervening nidus. The high turbulent flow of PAVFs and aggressive DAVFs with cortical venous reflux can result in venous outflow varix and aneurysmal dilatation. They pose a significant challenge to transvenous embolization (TVE), stereotactic radiosurgery, and surgical treatment. We aim to share our centers' experience with the transarterial embolization (TAE) for arteriovenous fistulas (AVFs) with large venous pouches and to report the outcome. Methods : The authors' two institutions' databases were retrospectively reviewed from February 2017 to February 2021. All patients with intracranial high flow PAVFs and aggressive DAVFs with venous outlet ectasia and large venous varix and were treated by TAE were included. Results : Fifteen patients harboring 11 DAVFs and four PAVFs met our inclusion criteria. All patients underwent TAE in 17 sessions. Complete angiographic obliteration was achieved after 14 sessions in 12 patients (80%). Four patients (25%) had residual after one TAE session. Technical failure was documented in one patient (6.7%). Fourteen patients (93.3%) had favorable functional outcome (modified Rankin score 0-2). Conclusions : TAE for high flow or aggressive intracranial AVFs is a safe and considerable treatment option, especially for those associated with large venous pouches that are challenging and relatively high-risk for TVE.