• Smart Structures and Systems
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• 제6권3호
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• pp.183-196
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• 2010

Monitoring and economical design of alternative energy generators such as wind turbines is becoming increasingly critical; however acquisition of the dynamic output data can be a time-consuming and costly process. In recent years, low-cost wireless sensors have emerged as an enabling technology for structural monitoring applications. In this study, wireless sensor networks are installed in three operational turbines in order to demonstrate their efficacy in this unique operational environment. The objectives of the first installation are to verify that vibrational (acceleration) data can be collected and transmitted within a turbine tower and that it is comparable to data collected using a traditional tethered system. In the second instrumentation, the wireless network includes strain gauges at the base of the structure. Also, data is collected regarding the performance of the wireless communication channels within the tower. In both turbines, collected wireless sensor data is used for off-line, output-only modal analysis of the ambiently (wind) excited turbine towers. The final installation is on a turbine with embedded braking capabilities within the nacelle to generate an "impulse-like" load at the top of the tower. This ability to apply such a load improves the modal analysis results obtained in cases where ambient excitation fails to be sufficiently broad-band or white. The improved loading allows for computation of true mode shapes, a necessary precursor to many conditional monitoring techniques.

• 대한안전경영과학회지
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• 제16권4호
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• pp.123-131
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• 2014

Modern weapon systems are getting more complex in terms of the functionality and also the conditions on the environment and range in which they are deployed and used. Therefore, many development programs can easily be exposed to a variety of risks, resulting in delayed schedules and cost overrun. As such, effective means are necessary to keep the defence budget at an affordable level while competitive edges on technological aspects are retained. As one way to meet those need, modeling and simulation (M&S) methods have widely been used, particularly in the test and evaluation (T&E) process for weapon systems development. The result of M&S-based systems development should be evaluated by the verification, validation & accreditation (VV&A) process to assure keeping reliability at a desired level. On the other hand, due to the explosiveness, the weapons systems development naturally requires to consider safety issues in both the T&E and operational periods. The purpose of this paper is to improve the VV&A process by reflecting the safety requirements therein. To do so, the VV&A process has been analyzed and graphically modeled first and then safety elements have been incorporated effectively. The use of the improved process in the war ships development has also been discussed. Based on the process proposed and the consequent database constructed, the target system can be expected to benefit from reducing development risks while assuring systems safety.

• 한국철도학회논문집
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• 제20권2호
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• pp.288-298
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• 2017

고속 및 일반철도 차량의 시스템이 다양화되고 성능 측면에서 상당한 기술발전에 이르고 있다. 통행자가 현재 인지하고 있는 철도 수단에 대한 시간 및 비용 개선에 따른 수단전환 특성을 분석하고 통행자들의 시간가치를 분석하고자 한다. 본 연구에서는 통행자의 수단선택 모형을 구축하고 개인의 선호다양성을 반영한 혼합로짓모형과의 비교를 수행한다. 또한, 도출된 모형에 의한 통행시간가치 추정을 통해서 분석의 타당성을 제시한다. 이에 본 연구에서는 대중교통 이용객 510여명을 대상으로 SP 조사를 통해 철도 차량 개선에 따른 철도의 통행비용 및 통행시간 변화에 따른 통행시간가치를 다양한 모형을 이용하여 제시하였다. 또한, 개인의 선호다양성을 반영한 다양한 모형 간 비교분석하였다. 본 연구를 통해 개인의 선호에 의한 한계대체율법을 통하여 철도의 통행시간가치를 추정함으로써 철도 사업에서의 통행시간 절감편익을 보다 정확하게 산정할 수 있다.

• 디지털융복합연구
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• 제14권8호
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• pp.47-56
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• 2016

본 연구는 산림분야 기후변화대응 R&D 사업을 통해 발생된 성과를 효율성 관점에서 분석하였다. 이를 위해 DEA(자료포락분석)를 활용하여 R&D 투자효과를 실증적으로 분석하였으며, 연구개발비와 인력 등의 투입(input)에 따라서 발생하는 과학적, 기술적, 사회적 성과의 산출(output) 및 결과(outcome)의 효율적 메카니즘을 규명하고, 세부 사업에서 어떠한 성과가 더 효율적으로 산출되는지를 심층적으로 분석하였다. Post-2012 온실가스 의무 감축 대응 산림정책 및 전략에 관한 연구과제가 과학적, 기술적, 사회적 성과에서 가장 참조 횟수가 많은 과제로 분석되어 가장 효율적인 것을 확인하였다. 이를 토대로 향후 R&D사업 추진의 핵심적 고려요소를 파악하고, 투자효과를 높일 수 있는 정책적인 시사점을 모색하였다.

• The Journal of Asian Finance, Economics and Business
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• 제7권11호
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• pp.1041-1047
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• 2020

The intention of this paper is to give a better understanding about the implementation of sustainable manufacturing practice in the textile companies in Indonesia as one of the promising sectors in the manufacturing industry. The data was collected by taking a case study approach in one of the leading textile companies in Indonesia. Questionnaire and interview techniques were used to gather in-depth information about the implementation of a sustainable concept in the company. The result reveals that the extent of the implementation of Sustainable Manufacturing Practices (SMP) in the companies are at a level of moderate to high. From the three dimensions measured which are environment, economy, and social dimensions, the evaluation result shows good performance in terms of the implementation of sustainable concepts, like low level of gas emission, high percentage of renewable energy usage, cost reduction rate, high quality of life, etc. From this result, the authors then develop a sustainable manufacturing model in the wider coverage to be implemented not only in the textile industry but is expected to be implemented in manufacturing sectors as well. This model consists of at least seven basic archetypes which are divided into three dominant areas: technological innovation, economical, and social areas which aim to bring better performance in the manufacturing industry of Indonesia.

• Journal of information and communication convergence engineering
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• 제8권4호
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• pp.437-442
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• 2010

Ubiquitous mobile computing is becoming easier and more attractive in this ambient technological Internet world. However, some portable devices such as Personal Digital Assistant (PDAs) and smart phones are still encountering inherent constraints of limited storages and computing resources. To alleviate this problem, we develop a cost-effective protocol, iATA to transfer ATA commands and data over TCP/IP network between mobile appliances and stationary servers. It provides mobile users a virtual storage platform which is physically resided at remote home or office. As communications are made through insecure Internet connections, security risks of adopting this service become a concern. There are many reported cases in the history where attackers masquerade as legitimate users, illegally access to network-based applications or systems by breaking through the poor authentication gates. In this paper, we propose a mutual authentication and secure session termination scheme as the first and last defense steps to combat identity thief and fraud threat in particular for iATA services. Random validation factors, large prime numbers, current timestamps, one-way hash functions and one-time session key are deployed accordingly in the scheme. Moreover, we employ the concept of hard factorization problem (HFP) in the termination phase to against fraud termination requests. Theoretical security analysis discussed in later section indicates the scheme supports mutual authentication and is robust against several attacks such as verifiers' impersonation, replay attack, denial-of-services (DoS) attack and so on.

• 한국항해학회지
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• 제18권2호
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• pp.91-109
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• 1994

Technological and organisational changes in transport system have introduced new dimension into port system development and inter-port competition. The quality of service now required by the customer is costly and not easily provided by small shipping companies and small ports. It has been suggested that in the future container shipping may be concentrated by space-sharing arrangements or actual mergers into the hands of a few mega-operators with the investment potential to provide total logistics networks. In order to compete effectively, high load factors will be essential and port concentration inevitable. A fa-voured few ports will become the load centres and other ports will assume a secondary feeder role. In this study, three questions are raised and attempts are made to answer them : (a) what is the new role of ports today ; (b) why should ports be engaged in this new role ; and (c) how can ports play this new role. In short, a modern port should be a service centre and a logistic platform for international trade and transport-a third generation port. Ports, in particular, have to make every effort to be competitive in the cost and quality of services and to make the port a transport and distribution service centre. For most ports, this is not an option but a must ; an essential requirement for survival in this win or lose situation. The best way to win is to maintain a close contact with port users, listen to them, discuss with them, help them and satisfy them. That is port marketing. Starting from the findings of port marketing, it is es-sential to work out appropriate development plans and marketing targets and to improve port competitive-ness. As an alternative method, a port competitiveness model is suggested, which may help port managers to make appropriate improvements.

• Genomics & Informatics
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• 제14권3호
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• pp.78-84
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• 2016

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (NKTCL), is a malignant disorder of cytotoxic lymphocytes of NK or T cells. It is an aggressive neoplasm with a very poor prognosis. Although extranodal NKTCL reportedly has a strong association with Epstein-Barr virus, the molecular pathogenesis of NKTCL has been unexplored. The recent technological advancements in next-generation sequencing (NGS) have made DNA sequencing cost- and time-effective, with more reliable results. Using the Ion Proton Comprehensive Cancer Panel, we sequenced 409 cancer-related genes to identify somatic mutations in five NKTCL tissue samples. The sequencing analysis detected 25 mutations in 21 genes. Among them, KMT2D, a histone modification-related gene, was the most frequently mutated gene (four of the five cases). This result was consistent with recent NGS studies that have suggested KMT2D as a novel driver gene in NKTCL. Mutations were also found in ARID1A, a chromatin remodeling gene, and TP53, which also recurred in recent NGS studies. We also found mutations in 18 novel candidate genes, with molecular functions that were potentially implicated in cancer development. We suggest that these genes may result in multiple oncogenic events and may be used as potential bio-markers of NKTCL in the future.

• 대한생식의학회:학술대회논문집
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• 대한불임학회 2003년도 제45차 추계학술대회
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• pp.21-30
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• 2003

As a result of the technological advance provided by intracytoplasmic sperm injection (ICSI) in 1992, the evaluation and treatment of the infertile male has changed significantly. Many men who were previously thought to be irreversibly infertile have the potential to initiate their own biologic pregnancy. However, not all men having impaired semen parameter are ideal candidates for ICSI for numerous reasons including a lack of addressing the underlying problem causing the male infertility, unknown genetic consequences, and cost-effectiveness issues. In this era of ICSI, the fundamental approach to the male with suspected subfertility is unchanged and is based on a history, physical examination, and focused laboratory testing. The urologist should approach the patient with an intent to identify remediable causes of subfertility given the specific clinical situation. For instance, should a gentleman have his varicocele repaired or vasectomy reversed, or should he proceed directly with ICSI? If no factors can be improved in a timely manner, then ICSI should be considered using the available sperm. Examples of recent advances include the diagnosis and treatment of ejaculatory duct obstruction, indications and techniques for performing testis biopsy, and technique for sperm harvesting. In addition, potential genetic causes of male subfertility should be diagnosed and discussed with the patient. Cystic fibrosis gene mutation, karyotype abnormallities, and Y-chromosome microdeletions all have recently been identified as causative for male infertility in otherwise phenotypically normal men. With recently evolved diagnostic and therapeutic techniques now available for the infertile couple, even the most severe male factor problems in patients previously considered irreversibly infertile are now potentially treatable. The physician should be aware of the availability and limitations of these new and exciting reproductive technologies because they will allow him to provide timely and more effective therapy for the infertile couple. An understanding of these advances by all physicians is important as we progress into the $21^{st}$ century

• 반도체디스플레이기술학회지
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• 제18권3호
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• pp.77-81
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• 2019

Recently, Korea has been making efforts at the government level to overcome the national crisis that Japan's dependency on technology in the semiconductor and display materials sectors has also escaped due to export regulations on three materials carried out by Japan. Therefore, based on the data of the National Science & Technology Information Service (NTIS) operated by the government, we analyze the trend of R & D investment in the display field, thereby improving R & D to improve material technology competitiveness in the future. Let's examine the implications of investment. A total of 5 years of new research and development investment in the field of display was invested as basic research fund for 25%, 15% for applied research, and 53% for development research. In terms of development cost and development period, the basic research showed that the amount of money and the development period were shorter than that of applied research. In other words, the basic research accounted for 25% of the R & D investment and the average R & D period was only 3.2 years. As we can see from the recent development of H fiber carbon fiber, which was recently developed and entered full-scale production, we were able to succeed because of the benefits of government support for 10 years while giving the same material title differently. In order to escape from Japan's technological dependence on semiconductor and display materials in Korea, As such, basic research in the field of materials is only possible when long-term research is conducted.