• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.673-697
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• 2018

BACKGROUND: Cartilage tissue engineering (CTE) aims to obtain a structure mimicking native cartilage tissue through the combination of relevant cells, three-dimensional scaffolds, and extraneous signals. Implantation of 'matured' constructs is thus expected to provide solution for treating large injury of articular cartilage. Type I collagen is widely used as scaffolds for CTE products undergoing clinical trial, owing to its ubiquitous biocompatibility and vast clinical approval. However, the long-term performance of pure type I collagen scaffolds would suffer from its limited chondrogenic capacity and inferior mechanical properties. This paper aims to provide insights necessary for advancing type I collagen scaffolds in the CTE applications. METHODS: Initially, the interactions of type I/II collagen with CTE-relevant cells [i.e., articular chondrocytes (ACs) and mesenchymal stem cells (MSCs)] are discussed. Next, the physical features and chemical composition of the scaffolds crucial to support chondrogenic activities of AC and MSC are highlighted. Attempts to optimize the collagen scaffolds by blending with natural/synthetic polymers are described. Hybrid strategy in which collagen and structural polymers are combined in non-blending manner is detailed. RESULTS: Type I collagen is sufficient to support cellular activities of ACs and MSCs; however it shows limited chondrogenic performance than type II collagen. Nonetheless, type I collagen is the clinically feasible option since type II collagen shows arthritogenic potency. Physical features of scaffolds such as internal structure, pore size, stiffness, etc. are shown to be crucial in influencing the differentiation fate and secreting extracellular matrixes from ACs and MSCs. Collagen can be blended with native or synthetic polymer to improve the mechanical and bioactivities of final composites. However, the versatility of blending strategy is limited due to denaturation of type I collagen at harsh processing condition. Hybrid strategy is successful in maximizing bioactivity of collagen scaffolds and mechanical robustness of structural polymer. CONCLUSION: Considering the previous improvements of physical and compositional properties of collagen scaffolds and recent manufacturing developments of structural polymer, it is concluded that hybrid strategy is a promising approach to advance further collagen-based scaffolds in CTE.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.9
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• pp.647-655
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• 2022

The Russian government is expanding strategic cooperation with foreign countries, including production partnerships, in order to secure civil aircraft manufacturing technology and advanced materials, with the aim of becoming the world's third-largest civil aircraft producer. In addition, the Russian government supports the development of the aircraft manufacturing industry and reorganizes the aircraft certification organization to pursue systematic aviation safety and make great efforts in international cooperation and certification activities for the export of aviation products. Establishing a cooperative system for safety and certification of civil aircraft between countries requires a process of mutual understanding and trust in the overall certification system. Therefore in this study, we wanted to analyze Russia's aircraft certification organization, law system, certification procedures to help Russia understand its aircraft certification system.

• Journal of dental hygiene science
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• v.23 no.3
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• pp.193-198
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• 2023

Background: The nose is located at the center of the face, and it is possible to determine race, sex, and the like. Research using the nasal index (NI) classification method to classify the shape of the nose is currently in progress. However, domestic research is required as most research is being conducted abroad. In this study, we used a 3D program to confirm the ratio of the nose shape of Koreans. Methods: One hundred patients (50 males and 50 females) in their 20s were evaluated (IRB approval no. DKUDH IRB 2020-01-007). Cone beam computed tomography was performed using the Mimics ver.22 (Materialise Co., Leuven, Belgium) 3D program to model the patient's skull and soft tissues into three views: coronal, sagittal, and frontal. To confirm the ratio of measurement metrics, analysis was performed using the SPSS ver. 23.0 (IBM Co., Armonk, NY, USA) program. Results: Ten leptorrhine (long and narrow) type, 76 mesorrhine (moderate shape) type, and 14 platyrrhine (broad and short) type noses were observed. In addition, as a result of sex comparison, five males had the leptorrhine (long and narrow) type, 40 mesorrhine (moderate shape), and five platyrrhine (broad and short) types. For females, five patients had the leptorrhine (long and narrow) type, 36 patients had the mesorrhine (moderate shape) type, and nine patients had the platyrrhine (broad and short) type. Conclusion: This study will be helpful when performing nose-related surgeries and procedures in clinical practice and for similar studies in the future.

• Journal of Korean society of Dental Hygiene
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• v.17 no.6
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• pp.1013-1024
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• 2017

Objectives: The study investigated health professionals working in the metropolitan area and Jeolla-bukdo, South Korea, from April 30 to May 17, 2017 to understand their views on the issue of including dental hygienists in the scope of medical personnel of South Korea. Methods:A total of 270 surveys were analyzed in this study. The survey consists of 5 questions on general issues; 10 on the awareness of present work of dental hygienist; and 1 on opposition or approval about including dental hygienist in medical personnel. The collected data were analyzed using SPSS for Windows 18.0, as well as frequency analysis, cross analysis and logistic regression analysis. Statistical significance level (${\alpha}$) is 0.05. Results: 1. Broken down by gender, male subjects showed more oppositions against including dental hygienists in the category of medical personnel while female subjects showed more favorable opinions (p<0.05). In terms of academic background, those who had graduated from graduate school or higher showed a higher propensity for opposition while those who had graduated from a 3-year college showed a higher tendency for approval on the idea (p<0.05), In terms of occupational type, health professionals showed more opposing views whereas medical technologists showed more approvals than others (p<0.001). 2. With respect to the awareness of work specialty and proficiency of dental hygienist according to general characteristics, the higher the age, the higher the awareness level was. In terms of the occupational type, medical technologists were found to have higher awareness level than health professionals (p<0.001). 3. With respect to the relationship between general characteristics and view on including dental hygienists in medical personnel, the occupational type of health professional was found to have 6.33 times more oppositions than medical technologists. When the awareness level on proficiency of dental hygienist was low, opposition was 6.52 times more frequent (p<0.05). Conclusions: Based on the findings above, the inclusion of dental hygienists in medical personnel seems necessary in properly establishing the specialty and role of dental hygienist in the dentist medical environment of the country in order to enhance national oral health related preventive dental service and expand the demand. To this end, it is necessary to provide nationwide promotion, work to change the awareness of health professionals in other occupational types, and facilitate public promotion for legal ground establishment.

• The Journal of KAIRB
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• v.5 no.1
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• pp.14-20
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• 2023

Purpose: To obtain fundamental data on selection tools for an internal audit and develop a new guideline. We scored the indicated points from the internal audit, identified the research progress and problems that occurred, and confirmed the validity of the risk factors involved. Methods: Of the 63 internal audits conducted by Keimyung University Dongsan Hospital from 2014 to 2021, we analyzed 55 clinical trials with an inspection checklist. We excluded 8 that failed to transfer data and refused to comply with the internal audit. The statistical summary of the collected data was verified and interpreted by using frequency analysis and a chi-square test. Result: Of total 55 cases included in the internal audit, sponsor-initiated trial (SIT) was 63.6% (vs. investigator-initiated trial [IIT]), clinical trial for investigational drug was 71.0% (vs. nonclinical or clinical trial for investigational device), domestic multicenter trial was 60.0% (vs. single center or multinational multicenter trial), and trial requisition for MFDS approval was 69.1% (vs. exception for MFDS approval). The 10 areas of the clinical trial inspection checklist (reports, protection of subjects, compliance with protocols, records, management of investigational drug and/or device, delegation of duties, qualification of investigators, management of specimen, contract-agreement and approval of protocols, and preservation of recorded documents) were weighted between 2 to 5 points. The average of the total points was 16.09±13.2 and 20 clinical trials were above the average. As a result of comparing the average of the total points weighted by year, the highest score was in 2020. The 4 factors that play significant roles in determining the internal quality were (1) principal subjects that initiated the clinical trials (p=0.049), (2) type (p=0.003), (3) phase of clinical trials (p=0.024), and (4) number of registered subjects reported at the time of continuing deliberation (p=0.019). Of the 10 areas of the clinical trial inspection checklist, 'record' was the most inappropriate and insufficient. We found more indicated points; the quality of performance declined in IIT, nonclinical trials, and other clinical trials that were not in phase I1-IV4, and the study of more than 30 registered subjects at the time of continuing review. Conclusion: If an institution has an internal audit selection tool that reflects the aforementioned risk factors, it will be possible to effectively manage high-risk studies; thereby, contributing to an efficient internal audit and improving the quality of clinical trials.

• Electronics and Telecommunications Trends
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• v.10 no.2 s.36
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• pp.125-135
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• 1995

형식승인제도는 몇년 전까지만 해도 전기통신 단말장치에 대한 정부의 고유한 통제와 권한의 영역이라고 생각할 만큼 규제 일변도의 정책 차원으로 다루어졌으나, 최근 통신시장 개방화 및 세계화 등과 같은 국제적인 통신환경을 반영한 단말장치의 통신망 접속 자유화가 실현됨에 따라 새로운 대내.외의 경쟁적 환경 위에서 운영하게 되었다. 특히, 최근에 각국은 다른 국가와의 형식승인 상호인정을 고려하면서 전기통신기술의 급격한 발전에 능동적 및 포괄적으로 대처하기 위한 전기통신 단말장치의 형식승인 적용 분류체계를 재조명하는 흐름을 보이고 있다. 이에, 본 고에서는 선진국의 형식승인 적용 대상 단말장치의 범위와 기능 및 용도별의 분류체계를 분석하여 항목별로 선정되고 있는 국내 형식승인 적용 대상 단말 장치의 분류체계를 선진국 수준의 기능 및 용도별로 개선하기 위한 방향을 모색해 보았다.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.1149-1154
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• 2007

Fluctuation of control rod was experienced when plant was operating in normal operation mode in WH type NPPs. In order to cope with increased control rod fluctuation, the lead-lag controller setpoint for rod control system was optimized and resulted in increasing the margin of operation and minimizing unnecessary control rod movement. By optimization of the time constant, the margin of operation was increased by $1.5^{\circ}F$ and the control rod movement was not occurred due to mitigation of temperature fluctuation in loop. According to the mitigation of time constant, the margin of operation was increased but safety margin can be affected badly, so that the influences to FSAR design reference was evaluated. As the result of this evaluation, it satisfied the design reference of the existing safety analysis and was applied to NPP after obtaining the approval.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.23 no.2
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• pp.57-62
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• 2015

As the issuance of type certificate and production certificate for KC-100 Naraon, Korea is ranked as the State of Design and the State of Manufacture for civil aircraft specified in the Convention on International Civil Aviation. It means that another responsibilities are imposed and new frameworks are required for the airworthiness management including the continuing airworthiness. So far the minimum airworthiness management system was sufficient as the State of Registry for the aircraft operations and safety management. However, we need to establish and maintain the airworthiness management system for the effective certification and oversight of our air operators and approval holders. This paper introduces the new obligations under the Convention on International Civil Aviation, reviews the current aviation regulations and procedures and presents the strategy for the establishment of the regulatory system to ensure the airworthiness of aircraft.

• Journal of Institute of Convergence Technology
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• v.4 no.2
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• pp.67-70
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• 2014

Recently EU has been recognized that there is a difference of emission quantity between emission certification test mode and real-road driving test. Accordingly the European Commission is currently preparing to require real-road testing as part of the passenger car type-approval process in the EU. vehicle manufacturers from 2017 are expected to test new vehicles not only under laboratory conditions but also on the real-road, using PEMS equipment. Therefore the purpose of this study is to analyze the emission and Fuel Economy of CVS-75 mode test using chassis dynamometer and RDE test using PEMS equipment by PHEV passenger car.

• Electronics and Telecommunications Trends
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• v.9 no.4
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• pp.83-98
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• 1994

통신 장비 및 서비스 시장의 개방화에 따른 국가간 경쟁 체제 속에서 통신 정책 입안자의 관심이 단말 장치에 대한 형식 승인 제도의 세부 규정과 절차의 명확성을 위한 각종 제도 장비, 그리고 단말 장치 기술 기준의 효율적 운용 방안 등에 모아지고 있다. 이를 반영하여 호주는 1991년 전기 통신법의 개정, 형식 승인 기관인 AUSTEL의 기능 강화, 국가 및 지역간의 형식 승인 조화를 위한 AUSTEL의 국제적인 각종 활동 등을 통하여 대내 외적으로 형식 승인제도와 형식승인 기술 기준의 미비점을 보완해왔으며, 현재 세계 각국과의 형식승인 상호인정을 위한 효율적인 활동체계를 구축하고 있다. 본 고는 단말 장치 형식 승인 제도 운영 등에 활발한 움직임을 보여주고 있는 호주의 형식 승인 지침(Technical Approvals Guide No.3)과 전화망 접속 기술 기준(TS-002)의 적용 동향을 파악하여, 최근 호주와 형식 승인 상호 인정을 계획하고 있는 우리나라의 통신 협상 대응 방안 설정시 활용하고자 한다.