• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.9 s.339
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• pp.85-96
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• 2005

A ' Virtual Private Network (YPN) over Internet' has the benefits of being cost-effective and flexible. However, given the increasing demands for high bandwidth Internet and for reliable services in a 'VPN over Intemet,' an IP/GMPLS over DWDM backbone network is regarded as a very favorable approach for the future 'Optical VPN (OVPN)' due to the benefits of transparency and high data rate. Nevertheless, OVPN still has survivability issues such that a temporary fault can lose a large amount of data in seconds, moreover unauthorized physical attack can also be made on purpose to eavesdrop the network through physical components. Also, logical attacks can manipulate or stop the operation of GMPLS control messages and menace the network survivability of OVPN. Thus, network survivability in OVPN (i.e. fault/attack tolerant recovery mechanism considering physical structure and optical components, and secured transmission of GMPLS control messages) is rising as a critical issue. In this Paper, we propose a new path establishment scheme under shared risk link group (SRLG) constraint for physical network survivability. And we also suggest a new logical survivability management mechanism by extending resource reservation protocol-traffic engineering extension (RSVP-TE+) and link management protocol (LMP). Finally, according to the results of our simulation, the proposed algorithms are revealed more effective in the view point of survivability.

• Magazine of the Korea Concrete Institute
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• v.5 no.4
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• pp.123-134
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• 1993

A rapid progress has been made over last decade in the state-of-the-art earthquake structura1 engineering towards a better understanding of both the earthqauke ground motion and structural response. These efforts seek to ensure that there will be no serious injury or loss of life in the event of earthquake, and that structures can be built at minimum cost. The design of structures in general, concrete structures in particular, to resist strong ground input motions is not a simple matter, and analytical models for such structures must be developed from a design perspective that accounts for the complexities of the structural responses. The primary obj ective of earthquake structural engineering research is to ensure the safety of structures by understanding and improving a design methodology. Ideally, this would require the development of an analytical model related to a design methodology that ensures a ductile performance. For the accurate assessment of the adequacy of analytically developed model, experiments conducted to study the inplane inelastic cyclic behavior of structures should verify the analytical approach. The fundamental goal of this paper is to present and demonstrate experimentally verified analytical methods that provide the adequate degree of safety and confidience in the behavior of reinforced concrete structural components. This study further attempts to extend the developed modeling techruque for use by practicing structural engineers for both the analysis and design.Plication of the relaxed diaphragm through left thoracotomy was done and result was excellent as seen on Fig. 5. Cause of eventration of the left hemidiaphragm was due to paralysis of the left phrenic nerve which was tested during thoracotomy.

• Journal of the Korea Convergence Society
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• v.8 no.3
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• pp.245-252
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• 2017

The purpose of this study is to analyze the effects of mergers and acquisitions of domestic IT companies on strategic aspects of internal capacity enhancement. Empirical analysis applied to this study analyzed the business performance in the market through the merger of Daum Communications and Kakao Group. After Daum pursued the merger with Kakao, it showed that the platform business of kakao is expanding to the domain of the existing portal site. The merger was completed, and the total value of the stocks went up to the highest level, but soon its value declined. The merger shows that the growth potential of the enterprise is temporarily declining, which seems to be the internal cost of the merger. Even in the case of profitability, the merger did not show positive results. In the case of stability, the expectation due to the merger was reflected and slightly increased. The following two companies were interested in the kakao when they viewed the merger through a chronological analysis. However, after the merger, the interest of the next kakao was similar. This is seen as a result of the expansion of kakao's diverse platform business rather than the following search sites. From the results of this study, it is suggested that domestic IT companies should approach by analyzing the strategic factors that generate synergy when pursuing M & A to strengthen their resources or capabilities.

• Carbon letters
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• v.23
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• pp.38-47
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• 2017

In this study, magnetite ($Fe_3O_4$) nanoparticles were electrochemically synthesized in an aqueous electrolyte at a given potential of -1.3 V for 180 s. Scanning electron microscopy revealed that dendrite-like $Fe_3O_4$ nanoparticles with a mean size of < 80 nm were electrodeposited on a glassy carbon electrode (GCE). The $Fe_3O_4/GCE$ was utilized for sensing chloramphenicol (CAP) by cyclic voltammetry and square wave voltammetry. A reduction peak of CAP at the $Fe_3O_4/GCE$ was observed at 0.62 V, whereas the uncoated GCE exhibited a very small response compared to that of the $Fe_3O_4/GCE$. The electrocatalytic ability of $Fe_3O_4$ was mainly attributed to the formation of Fe(VI) during the anodic scan, and its reduction to Fe(III) on the cathodic scan facilitated the sensing of CAP. The effects of pH and scan rate were measured to determine the optimum conditions at which the $Fe_3O_4/GCE$ exhibited the highest sensitivity with a lower detection limit. The reduction current for CAP was proportional to its concentration under optimized conditions in a range of $0.09-47{\mu}M$ with a correlation coefficient of 0.9919 and a limit of detection of $0.09{\mu}M$ (S/N=3). Moreover, the fabricated sensor exhibited anti-interference ability towards 4-nitrophenol, thiamphenicol, and 4-nitrobenzamide. The developed electrochemical sensor is a cost effective, reliable, and straightforward approach for the electrochemical determination of CAP in real time applications.

• Journal of IKEEE
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• v.18 no.2
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• pp.272-281
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• 2014

In electrical impedance tomography (EIT), modified Newton Raphson (mNR) method is widely used inverse algorithm for static image reconstruction due to its convergence speed and estimation accuracy. The unknown conductivity distribution is estimated iteratively by minimizing a cost functional such that the residual error namely the difference in measured and calculated voltages is reduced. Although, mNR method has good estimation performance, EIT inverse problem still suffers from ill-conditioned and ill-posedness nature. To mitigate the ill-posedness, generally, regularization methods are adopted. The inverse solution is highly dependent on the choice of regularization parameter. In most cases, the regularization parameter has a constant value and is chosen based on experience or trail and error approach. In situations, when the internal distribution changes or with high measurement noise, the solution does not get converged with the use of constant regularization parameter. Therefore, in this paper, in order to improve the image reconstruction performance, we propose a new scheme to determine the regularization parameter. The regularization parameter is computed based on residual error and updated every iteration. The proposed scheme is tested with numerical simulations and laboratory phantom experiments. The results show an improved reconstruction performance when using the proposed regularization scheme as compared to constant regularization scheme.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 1995.12a
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• pp.9-21
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• 1995

A planning support system enhances our ability to use water capacity expansion as an urban growth management strategy. This paper reports the development of capacity expansion modeling of water supply as part of the continuing development of such a planning support system (PEGASUS: Planning Environment for Generation and Analysis of Spatial Urban Systems) to incorporate water supply, This system is designed from the understanding that land use and development drive the demand for infrastructure and infrastructure can have a significant influence on the ways in which land is developed and used. Capacity expansion Problems of water supply can be solved in two ways: 1) optimal control theory, and 2) mixed integer nonlinear programming (MINLP). Each method has its strengths and weaknesses. In this study the MINLP approach is used because of its strength of determining expansion sizing and timing simultaneously. A dynamic network optimization model and a water-distribution network analysis model can address the dynamic interdependence between water planning and land use planning. While the water-distribution network analysis model evaluates the performance of generated networks over time, the dynamic optimization model chooses alternatives to meet expanding water needs. In addition, the user and capacity expansion modeling-to-generate-alternatives (MGA) can generate alternatives. A cost benefit analysis module using a normalization technique helps in choosing the most economical among those alternatives. GIS provide a tool for estimating the volume of demanded water and showing results of the capacity expansion model.

• World Technopolis Review
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• v.3 no.2
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• pp.89-96
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• 2014

Center for Research of Science and Technology ("PUSPIPTEK") has 460 hectares land area, still maintained as a green area with more than 30% green space. There are 47 centers for research and testing technology, technology-based industries, and as well as public supporting facilities in PUSPIPTEK area. Based on the concepts developed to make this area as an ecological region, PUSPIPTEK can be seen as a model of eco-innovation. The purpose of this research is to develop a model of water, energy and waste management with eco-innovation concept. As a new approach in addressing environmental degradation and maintaining the sustainability of ecosystem, studies related to eco-innovation policy that combines the management of water, energy and waste in the region has not been done. In order to achieve the objectives of the research, a series of techniques for collecting data on PUSPIPTEK existing conditions will be carried out, which includes utilities data (water, electricity, sewage) and master plan of this area. The savings over the implementation of the concept of eco-innovation in water, energy, and waste management were calculated and analyzed using quatitative methods. The amount of cost savings and feasibility were then calculated. Eco innovation in water management among other innovations include the provision of alternative sources of water, overflow of rain water and water environments utilization, and use of gravity to replace the pumping function. Eco-innovation in energy management innovations include the use of LED and solar cell for air conditioning. Eco-innovation in waste management includes methods of composting for organic waste management. The research results: (1) The savings that can be achieved with the implementation of eco innovation in the water management is Rp. 3,032,640 daily, or Rp.1,106,913,600 annually; (2) The savings derived from the implementation of eco innovation through replacement of central AC to AC LiBr Solar Powered will be saved Rp.1,933,992,990 annually and the use of LED lights in the Public street lighting PUSPIPTEK saved Rp.163,454,433 annually; (3) Application of eco innovation in waste management will be able to raise awareness of the environment by sorting organic, inorganic and plastic waste. Composting and plastic waste obtained from the sale revenue of Rp. 44,016,000 per year; (4) Overall, implementation of the eco-innovation system in PUSPIPTEK area can saves Rp. 3,248,377,023 per year, compared to the existing system; and (5)The savings are obtained with implementation of eco-innovation is considered as income. Analysis of the feasibility of the implementation of eco-innovation in water, energy, and waste management in PUSPIPTEK give NPV at a 15% discount factor in Rp. 3,895,228,761; 23.20% of IRR and 4.48 years of PBP. Thus the model of eco-innovation in the area PUSPIPTEK is feasible to implement.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.11
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• pp.1145-1151
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• 2015

High pressure components of a gas turbine engine must operate for a long life under severe conditions in order to maximize the performance and minimize the maintenance cost. Enhanced cooling design, thermal barrier coating techniques, and nickel-base superalloys have been applied for overcoming them and furthermore, material modeling, finite element analysis, statistical techniques, and etc. in design stage have been utilized widely. This article aims to evaluate the effects on the low cycle fatigue life of the high pressure turbine nozzle caused by different turbine inlet temperature profiles and installation conditions and to investigate the most favorable operating condition to the turbine nozzle. To achieve it, the structural analysis, which utilized the results of conjugate heat transfer analysis as loading boundary conditions, was performed and its results were the input for the assessment of low cycle fatigue life at several critical zones.

• The Journal of Fisheries Business Administration
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• v.51 no.1
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• pp.37-52
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• 2020

The production of abalone seed has grown and been specialized since the 2000s with the growth of the abalone farming industry. Despite the increase in the production of abalone seeds, the sales volume of abalone seeds remained flat and competition among producers increased. This paper will analyze the management efficiency of abalone seed production fishery to diagnose the management status and improve the abalone seed production efficiency. In addition, this study is the result of the basic research on the abalone seed industry and it is meaningful to prepare a platform for further research since the management status survey and the management efficiency survey of abalone seed production fishery have not been conducted until now. The data on the farmed fish prices of abalone seeds were collected from surveys of sample fish as part of the fish seed observation project conducted by the Fisheries Outlook Center (FOC) of Korea Maritime and Fisheries Development Institute (KMI). Management efficiency analysis utilizes DEA (Data Envelopment Analysis) model. The DEA model was analyzed by classifying into CCR (Super-CCR), BCC, and SBM (Super-SBM) models according to the assumptions taking into account the characteristics of the industry. The slack considered in the SBM model was judged as possible decreases in input variables and increase in output variables. The average efficiency from the CCR model was analyzed to be 69%. The BCC model was classified into input and output orientations, and the average efficiency was 79% and 75%, respectively. There were seven production fisheries with an SE value of 1 or more, which remained unchanged in terms of size and could be benchmarked. The average efficiency of the SBM model was 59% for CRS and 66% for VRS. Under the VRS assumptions, the variable increase/decrease efficiency analysis shows that labor costs can be reduced by 37.3%, facility capacity by 18.8%, and operating costs by 8.5%. In order to improve management efficiency, Wando needs to reduce labor and management costs. In Jindo region, sales increase as well as labor cost reduction is urgent. In other regions, reduced facilities and increased sales are recommended.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.187-192
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• 2014

Various researches are performed to extract significant features from continuous images. The FAST algorithm has the simple structure for arithmetic operation and it is easy to extraction the features in real time. For this reason, the FPGA based hardware accelerator is implemented and widely applied for the FAST algorithm. The hardware accelerator needs the threshold to extract the features from images. The threshold is influenced not only the number of extracted features but also the total execution time. Therefore, the way of threshold control is important to stabilize the total execution time and to extract features as much as possible. In order to control the threshold, this paper proposes the PI controller. The function and performance for the proposed PI controller are verified by using test images and the PI control logic is designed based on Xilinx Vertex IV FPGA. The proposed scheme can be implemented by adding 47 Flip Flops, 146 LUTs, and 91 Slices to the FAST hardware accelerator. This proposed approach only occupies 2.1% of Flip Flop, 4.4% of LUTs, and 4.5% of Slices and can be regarded as a small portion of hardware cost.