• Journal of the Korean Society of Systems Engineering
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• v.10 no.1
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• pp.1-15
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• 2014

Refinery plant producing petroleum products from crude oil has significantly contributed to the creation of the national interests as a leading engineering industries. However, domestic Engineering Procurement Construction (EPC) companies are facing heavy competition for orders. Domestic EPC companies as EPC contractors are faced with some problems such as undertaking responsibility for FEED packages produced by other FEED companies. But domestic EPC contractors are unfamiliar to development and validation of FEED packages. It causes poor profitability and lower competitiveness of domestic companies. It is necessary for domestic companies to have capability to perform FEED activities in order to overcome these limitations instead of focusing on EPC phase after FEED phase. The systematic procedure is needed to perform the FEED activities, however, there are present difficulties on it due to the lack of experience in FEED packages development which require various engineering knowledge of chemical process, mechanics, electrics, instrumentation, civil engineering. This study has applied systems engineering method which is multi-disciplinary approach to derive and verify the solution to meet the customer's needs when the complex system is developed to task execution process development of FEED activities for refinery plant. The problems that may occur in the future were identified in advance by taking into account the various stakeholders and system context through the application of systems engineering. It helps to develop the task execution process systematically. The developed task execution process of FEED activities is planned to make effectiveness verified by engineering professionals experienced in FEED and continually enhance this process by field application.

• Korean Journal of Construction Engineering and Management
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• v.12 no.6
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• pp.22-30
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• 2011

In the construction operation, foundation work should be done in advance for the building structure to be installed. This foundation work include a number of activities such as excavation, ground water prevention, piling, wale installation, etc. Caution should be taken in the operation because the dynamics of earth movement can cause a significant failure in the temporary structure. The temporary structure, therefore, should be constantly monitored to understand its behavior. This paper introduces the USN-based monitoring system to automatically identify the behavior of the temporary structure in addition to visual inspection. The autonomous capability of the monitoring system can increase the safety in the construction operation by providing the detailed structural changes of temporary structures.

• Spatial Information Research
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• v.23 no.4
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• pp.33-46
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• 2015

The fact that the limits of information recency, diversity, and usability are mainly caused by the supply oriented geospatial data and service development is commonly recognized. It is recently tried to overcome the limits by facilitating user experience and VGI(Volunteered Geographic Information) in several geospatial web services. This study suggests conceptual architecture and service scenario for geospatial collaborative platform prototype through review and examination of previous researches. The prototype, composed of 4 unit modules: 3D POI Creation Module, 3D POI Application Module, 3D POI/Event Management Module, 3D POI/Event Monitoring Module, provides the capability of collaboratively dealing with geospatial work. The suggested service scenario is demonstrated by developing prototype for the service modules.

• Earthquakes and Structures
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• v.11 no.6
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• pp.925-942
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• 2016

With ongoing development of earthquake engineering research and the lessons learnt from a series of strong earthquakes, the seismic design concept of "resilience" has received much attention. Resilience describes the capability of a structure or a city to recover rapidly after earthquakes or other disasters. As one of the main features of urban constructions, tall buildings have greater impact on the sustainability and resilience of major cities. Therefore, it is important and timely to quantify their seismic resilience. In this work, a quantitative comparison of the seismic resilience of two tall buildings designed according to the Chinese and US seismic design codes was conducted. The prototype building, originally designed according to the US code as part of the Tall Building Initiative (TBI) Project, was redesigned in this work according to the Chinese codes under the same design conditions. Two refined nonlinear finite element (FE) models were established for both cases and their seismic responses were evaluated at different earthquake intensities, including the service level earthquake (SLE), the design-based earthquake (DBE) and the maximum considered earthquake (MCE). In addition, the collapse fragility functions of these two building models were established through incremental dynamic analysis (IDA). Based on the numerical results, the seismic resilience of both models was quantified and compared using the new-generation seismic performance assessment method proposed by FEMA P-58. The outcomes of this study indicate that the seismic resilience of the building according to the Chinese design is slightly better than that according to the US design. The conclusions drawn from this research are expected to guide further in-depth studies on improving the seismic resilience of tall buildings.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.447-453
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• 2016

Recently, the design and supervision separating system has have been widely adopted in Korea. In this system, the owner should exclude the architect who designed the building from supervisor in the same project. The design and supervision separating system has advantage of less fraudulent construction and weakness of design intention reflection difficulty in construction stage. In this study, the status, problems and solutions of this system are identified from expert survey and interview. The main results of this study are as follows. First, the work scope of designer and supervisor should be clear and the guidelines for this system should be clearly defined. Second, the optimal price for the work scope should be guaranteed. Also, the education program for the improvement of supervisor capability should be provided.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.17-22
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• 2011

There are some degradation factors for amorphous silicon solar cells. Light inducing is one of the factor that explained by Staebler-Wronski effect. Also, hotspot heating could be the reason that makes amorphous silicon solar cell degrade. Hotspot heating is occurred when a solar cell is shaded so this work is investigated into two types of shading condition and how these affect to solar cell differently. Reduced irradiance for whole cell and partially shaded as 0($W/m^2$) while the other part of cell is soaking as 1000($W/m^2$) of irradiance are two conditions that are experimented. The two types of shading show different characteristics of degradations. The result shows that partially shaded cell dropped maximum powerless and slower. Also sudden drop points have shown that should be concerned to decide the number of cells for a string. Otherwise, the current through a shaded cell might flow more than cell's capability. It makes cell and module damaged. This work would help to manufacture modules.

• Journal of the Korea Safety Management & Science
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• v.19 no.1
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• pp.15-25
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• 2017

The findings were summarized as follows. The safety check by manufacturer showed that 6 of 13 companies are over the average occurrence of defects. It was expected that there would be a difference between manufacturing technology capability and production system of each manufacturer. Consequently, manufacturers should institutionally improve and strengthen certification items for the upward standardization of safety certification before factory. Second, the safety check by year showed that the results of this study accord with those of previous studies on defect time. Consequently, manufacturers should classify the 3-year-old equipment for vehicle-mounted MEWP into a special check subject to do a nondestructive test according to proven results, and also reflect the test in a safety test system to do regular preventive activities of equipment defects. Third, the safety check by part showed that the boom and outrigger parts of vehicle-mounted MEWP have the most defects. Stress concentration resulted in defects as the boom part was most frequently operated in the structural parts for a real work. To prevent this, it is suitable to improve the hardness of boom materials. The outrigger part needs improvement in safety devices with materials. As an outrigger supports the overturning moment of equipment, it is most affected by its load based on the operating radius, resulting in fatigue crack.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.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.

• Journal of the Korea Furniture Society
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• v.20 no.5
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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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• v.40 no.4
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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.