• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.347-352
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• 2006

Narrowband interference can severely degrade the performance of GPS receivers. Detecting the presence of interference and then characterizing it can lead to its removal. Receivers can be reconfigured to focus on other signals or satellites that are less vulnerable to that interference at that moment. Using hardware reconfigurability of FPGA receivers and characterizing the effect of narrowband interference on the GNSS signal quality lead us to a new RFI mitigation technique in which the highest quality and less vulnerable signal can be chosen at each moment. In the previous work [1], the post processing capability of a software GPS receiver, has been used to detect and characterize the CW interference. This is achieved by passing the GPS signal and the interference through the correlator. Then, using the conventional definition of C/No as the squared mean of the correlator output divided by its variance, the actual C/No for each satellite is calculated. In this work, first the 'Exclusion zone' for each satellite signal has been defined and then by using some experiments the effects of different parameters like signal power, jamming power and the environmental noise power on the Exclusion zone have been analyzed. By monitoring the Doppler frequency of each satellite and using the actual C/No of each satellite using the traditional definition of C/No and actual data from a software GPS receiver, the decision to reconfigure the receiver to other signal can be made.

• 한국가구학회지
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• 제20권5호
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• pp.467-479
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• 2009

The high-tech computer technology developments have greatly affected the area of design education. Starting from the mid 80s, innovations in visual presentation methods have heightened with 2D computer graphic programs, CAD & 3D modeling, and Rapid Prototype that allows dimensional generation. The specialty and quality in design studio education have advanced due to the development in presentation methods such as Power Point and Keynote. But there are many problems with the current method of presenting the visual outcome in a data format using beam projectors, which is a vertical presenting method compared to the old studio study method of conducting discussions and reviews based on the substantial outcome. The essence of studio study that allows for comparisons and analysis by horizontally opening up the various work outcomes is being offset. Also the requirement for manual idea sketching work that plays an important role in the initial design phase continuing to decrease due to the digital working process dependence and cumbersome procedures in the presentation. In order to resolve this problem, the CALM system (Class Applied LCD Modular System) has been developed that replaces the method of attaching the sketches or renderings on the wall with a digital multi-display system. In a nutshell, individuals will upload the outcomes online and display them on the CALM system studio that is composed of 32 LCD (Columns: 4 $\times$ Rows: 8) monitors that are 19 inches in size so that various personnel can openly study the design outcomes. Also the central 42 inch PDP monitor that offers touch pad capability allows each design outcome to be described and examined by expanding. The concept phase of this development process has elevated to the production of an operating prototype that is being reviewed of its practicality. It is considered that the development of this system will decrease the extreme tendency of depending on digital operation but achieve revitalization of a more realistic and opened studio study environment compared to the individual consulting method of the old study approach.

• Ocean and Polar Research
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• 제40권4호
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• pp.259-270
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• 2018

The purpose of this study is to provide information to understand the context of the Antarctic Treaty System by looking back on its development process. It also aims to review the roles and activities of the CEP in the System in order to support the improvement of our Antarctic science policy. This study considered the developmental histories of independent conventions for Antarctic conservation and Protocol on Environmental Protection to the Antarctic Treaty under the system. CEP, established in accordance with the Protocol, has expanded its roles in the ATCM under the circumstances of climate change and increasing human activities in the treaty area. I examined CEP's functions, relationships with formal observers, and its activities along with CCRWP. In addition, I have estimated the contribution of the Parties to the CEP based on the documents submitted by the Parties. The leading Parties of the System have strengthened their initiatives to expand contributions to CEP with their output based on national Antarctic Program. However, Korea has not been able to take initiatives in the System even though Korea has invested considerable resources in its Antarctic program. To strengthen Korea's capability to instigate initiatives in the system, I suggest the following approaches: Firstly, Korea should improve its Antarctic science policy based on the newly established CEP five-year work plan; Secondly, Korea should organize a long-standing expert group to focus on Antarctic environmental policy and related scientific information; finally, Korea should intensify its collaboration with other Parties in developing Antarctic environmental priority issues.

• 기록학연구
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• 제47호
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• pp.227-254
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• 2016

이 연구는 공공기록물법 개정안의 주요 내용인 '외부전자기록물저장시설'의 전자기록 보존 업무에 대해 살펴보았다. 외부시설로서 공인전자문서센터가 공공기록물 법제가 요구하는 수준으로 기록의 보존업무를 위탁관리 할 수 있는지를 검토하는 것을 목적으로 한다. 이를 위해 유력한 외부시설로 거론되는 공전센터 제도의 현황에 대해 알아보았다. 그리고 기록의 보존 업무가 의미하는 바가 무엇인지를 이해하기 위해 주요 기록학 개념들을 정리하고, 법개정 과정에서 관련 공동체의 이해에 따라 주요 개념이 혼용되고 있음을 지적하였다. 마지막으로 공전센터가 현재의 관련 규정을 기반으로 기록관리 업무를 수행할 능력이 있는지를 검토하기위해, 공공기록물법 및 표준과 공전센터 업무 준칙의 규정, 그리고 공전센터 관련 국내표준의 내용을 비교하여 분석하였다. 그 결과 기록관리 법제가 요구하는 대부분의 규정이 마련되어 있지 않아 공전센터가 기록관리 업무 수행 역량을 갖추지 못한 상태임을 확인하였다. 기록관리 법제를 준수하는 업무 프로세스의 정립과 인증기준 마련이 선행되어야 함을 논의하였다.

• Current Photovoltaic Research
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• 제9권2호
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• pp.51-58
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• 2021

Solar water pumping system (SWPS) is reliable and beneficial for Indian farmers in irrigation and crop production without accessing utility. The capability of easy installation and deployment, makes it an attractive option in remote areas without grid access. The selection of portable solar based pumps is pertaining to its longer life and economic viability due to lower running cost. The work presented in this manuscript intends to demonstrate performance analysis of portable systems. Consequent investigation reveals PSWS as the emerging option for rural household and marginal farmers. This can be attributed to the fact that, a considerable portion (around 45.7%) of the country's land is farmland and irrigation options are yet to reach farmers who entirely rely on rain water at present for harvesting of the crops. According to census 2010-2011 tube wells are the main source for irrigation amongst all other sources followed by canals. Out of the total 64.57-million-hectare net irrigation area, 48.16% is accounted by small and marginal holdings, 43.77% by semi-medium and medium holdings, and 8.07% by large holdings. As per 2015-16 census data, nearly 100 million farming households would struggle to make ends meet. The work included in this manuscript, presents the performance of different commercial brands and different technologies of DC surface solar water micro pumping systems have been studied (specifically, the centrifugal and reciprocating type pumps have been considered for analysis). The performance of the pumping systems has been analyzed and data is evaluated in terms of quantity of water impelled for specific head. The reciprocating pump has been observed to deliver the best system efficiency.

• Advances in environmental research
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• 제10권1호
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• pp.87-103
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• 2021

Anaerobic digestion (AD) refers to the biological process which can convert organic substrates to biogas in the absence of oxygen. The aim of this study was to determine the capability of feedstock to produce biogas and to quantify the biogas yield from different feedstocks. A co-digestion approach was carried out in a continuous stirred tank reactor operated under mesophilic conditions and at a constant organic loading rate of 0.0756 g COD/ L.day, with a hydraulic retention time of 25 days. For comparison, mono-digestion was also included in the experimental work. 2 L working volumes were used throughout the experimental work. The seed culture was obtained from composting as substrate digestion. When the feedstock was added to seeding, the biogas started to emit after three days of retention time. The highest volume of biogas was observed when the seeding volume used for 1000mL. However, the lowest volume of biogas yield was obtained from both co-digestion reactors, with a value of 340 mL. For methane yield, the highest methane production rate was 0.16 L CH4/mg. The COD with yield was at 8.6% and the lowest was at 0.5%. The highest quantity of methane was obtained from a reactor of Euphorbiaceae peel with added seeding, while the lowest methane yield came from a reactor of Euphorbiaceae stems with added seeding. In this study, sodium bicarbonate (NaHCO3) was used as a buffering solution to correct the pH in the reactor if the reactor condition was found to be in a souring or acidic condition.

• Nuclear Engineering and Technology
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• 제53권12호
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• pp.3879-3891
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• 2021

A heat pipe residual heat removal system is proposed to be incorporated into the reactor driven subcritical (RDS) facility, which has been proposed by MIT Nuclear Reactor Laboratory for testing and demonstrating the Fluoride-salt-cooled High-temperature Reactor (FHR). It aims to reduce the risk of the system operation after the shutdown of the facility. One of the main components of the system is an air-cooled heat pipe heat exchanger. The alkali-metal high-temperature heat pipe was designed to meet the operation temperature and residual heat removal requirement of the facility. The heat pipe model developed in the previous work was adopted to simulate the designed heat pipe and assess the heat transport capability. 3D numerical simulation of the subcritical facility active zone was performed by the commercial CFD software STAR CCM + to investigate the operation characteristics of this proposed system. The thermal resistance network of the heat pipe was built and incorporated into the CFD model. The nominal condition, partial loss of air flow accident and partial heat pipe failure accident were simulated and analyzed. The results show that the residual heat removal system can provide sufficient cooling of the subcritical facility with a remarkable safety margin. The heat pipe can work under the recommended operation temperature range and the heat flux is below all thermal limits. The facility peak temperature is also lower than the safety limits.

• 한국정보전자통신기술학회논문지
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• 제17권4호
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• pp.275-287
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• 2024

과거부터 꾸준히 지식 그래프(Knowledge Graph)와 언어 모델(LM, Language Model)의 통합에 대한 많은 연구가 다뤄지고 있다. 그 중, 지식 그래프의 구조화된 지식을 이용해 자동 텍스트 생성을 다루는 연구는 그리 활성화되지 않았다. 본 연구에서는 기존 논문들과 비슷한 수준의 특정 도메인 관련 연구 항목(Related Work)을 자동 생성하기 위한 방법론, 즉, '1) 최적의 Prompt 선정, 2) 4단계 정제기법을 통해 Triple 추출, 3) 지식 그래프 구축, 4) 관련 연구 자동 생성'을 제안한다. 제안된 방법론은 대규모 언어 모델(LLM) 중, GPT-4를 활용하고, 4단계 정제 기법을 적용하여 관련 연구를 자동으로 생성하도록 설계했다. 그렇게 설계된 모델은 Triple 추출에서 #Supp, #Cont, Fluency에서 17.3, 14.1, 4.2의 성능과 GPT-4 자동 평가 기준, 100점 기준 정제 전, 88.5점에서 정제 후, 96.5점으로 기존 논문과 비슷한 수준의 유의미한 관련 연구 자동 생성 능력을 보였다.

• 한국건축시공학회지
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• 제14권6호
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• pp.561-569
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• 2014

본 연구는 시공단계 BIM 도입과 관련된 문헌고찰을 통해 문제점을 파악하고, 전문가 면담 및 현장실무자 대상으로 설문조사를 통해 실질적인 BIM 활성화 방안을 제시하는 것을 목표로 한다. 현행 BIM을 통한 시공성 분석 및 검토 관련 연구는 개념 정립과 업무 프로세스 등의 규명과 적용에 관한 연구가 대부분이며, 실질적인 건설프로젝트 현장실무자를 위한 연구는 진행된 바가 없음에 본 연구는 기 연구방식과의 차별화된 점이라 할 수 있다. 이를 위해 본 연구에서는 현재 국내 건설 기술자들의 BIM 도입 시공성 분석에 대한 필요성 및 BIM을 도입해 수행했으면 하는 시공성 분석 업무 분야의 세부적 내용, 그리고 기존의 시공성 분석 업무에 대한 문제점을 개선하고 효율적인 업무수행을 위한 대안으로 BIM을 적용한 시공성 분석방안을 이론적으로 조사하고, 도출된 사항을 현장 실무자 대상 설문조사를 통해 실질적인 현장적용 우선순위인 공종간 간섭체크 및 시각화에 대한 내용을 도출하였다. 또한 도출된 내용을 적용한 개선된 시공성 검토 프로세스를 제시하였다. 본 연구는 건설현장 BIM 도입을 위한 현장실무자 관점 BIM 기능 요소 도출, 프로세스 개선 및 협업도구에 초점을 맞추어 진행하였으므로, 향후 현장실무자 관점 BIM 기반 시공성 분석 협업체계에 대한 프로세스 정립 및 공사 관리를 위한 견적 공정 시뮬레이션 업무 프로세스 정립과 BIM 저작도구를 전면적 개선이 아닌 부분적 개선을 통한 BIM 도입 현장적용 방안에 대한 추가 연구가 필요한 것으로 파악되어진다.

• Asia pacific journal of information systems
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• 제22권2호
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• pp.39-69
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• 2012

With the advent of communication technologies including electronic collaborative tools and conferencing systems provided over the Internet, virtual collaboration is becoming increasingly common in organizations. Virtual collaboration refers to an environment in which the people working together are interdependent in their tasks, share responsibility for outcomes, are geographically dispersed, and rely on mediated rather than face-to face, communication to produce an outcome. Research suggests that new sets of individual skill, knowledge, and ability (SKAs) are required to perform effectively in today's virtualized workplace, which is labeled as individual virtual competence. It is also argued that use of online social networking sites may influence not only individuals' daily lives but also their capability to manage their work-related relationships in organizations, which in turn leads to better performance. The existing research regarding (1) the relationship between virtual competence and task performance and (2) the relationship between online networking and task performance has been conducted based on different theoretical perspectives so that little is known about how online social networking and virtual competence interplay to predict individuals' task performance. To fill this gap, this study raises the following research questions: (1) What is the individual virtual competence required for better adjustment to the virtual collaboration environment? (2) How does online networking via diverse social network service sites influence individuals' task performance in organizations? (3) How do the joint effects of individual virtual competence and online networking influence task performance? To address these research questions, we first draw on the prior literature and derive four dimensions of individual virtual competence that are related with an individual's self-concept, knowledge and ability. Computer self-efficacy is defined as the extent to which an individual beliefs in his or her ability to use computer technology broadly. Remotework self-efficacy is defined as the extent to which an individual beliefs in his or her ability to work and perform joint tasks with others in virtual settings. Virtual media skill is defined as the degree of confidence of individuals to function in their work role without face-to-face interactions. Virtual social skill is an individual's skill level in using technologies to communicate in virtual settings to their full potential. It should be noted that the concept of virtual social skill is different from the self-efficacy and captures an individual's cognition-based ability to build social relationships with others in virtual settings. Next, we discuss how online networking influences both individual virtual competence and task performance based on the social network theory and the social learning theory. We argue that online networking may enhance individuals' capability in expanding their social networks with low costs. We also argue that online networking may enable individuals to learn the necessary skills regarding how they use technological functions, communicate with others, and share information and make social relations using the technical functions provided by electronic media, consequently increasing individual virtual competence. To examine the relationships among online networking, virtual competence, and task performance, we developed research models (the mediation, interaction, and additive models, respectively) by integrating the social network theory and the social learning theory. Using data from 112 employees of a virtualized company, we tested the proposed research models. The results of analysis partly support the mediation model in that online social networking positively influences individuals' computer self-efficacy, virtual social skill, and virtual media skill, which are key predictors of individuals' task performance. Furthermore, the results of the analysis partly support the interaction model in that the level of remotework self-efficacy moderates the relationship between online social networking and task performance. The results paint a picture of people adjusting to virtual collaboration that constrains and enables their task performance. This study contributes to research and practice. First, we suggest a shift of research focus to the individual level when examining virtual phenomena and theorize that online social networking can enhance individual virtual competence in some aspects. Second, we replicate and advance the prior competence literature by linking each component of virtual competence and objective task performance. The results of this study provide useful insights into how human resource responsibilities assess employees' weakness and strength when they organize virtualized groups or projects. Furthermore, it provides managers with insights into the kinds of development or training programs that they can engage in with their employees to advance their ability to undertake virtual work.