• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.591-595
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• 2010

Conventional methods of model evaluation usually rely only on model performance based on a comparison of simulated variables to corresponding observations. However, this type of model evaluation has been criticized because of its insufficient consideration of the various uncertainty sources involved in modeling processes. This study aims to propose an extended model evaluation method using multiple assesment indices (MAIs) that consider not only the model performance but also the model structure and parameter uncertainties in rainfall-runoff modeling. A simple reservoir model (SFM) and distributed kinematic wave models (KWMSS1 and KWMSS2 using topography from 250m, 500m, and 1km digital elevation models) were developed and assessed by three MAIs for model performance, model structural stability, and parameter identifiability. All the models provided acceptable performance in terms of a global response, but the simpler SFM and KWMSS1 could not accurately represent the local behaviors of hydrographs. In addition, SFM and KWMSS1 were structurally unstable; their performance was sensitive to the applied objective functions. On the other hand, the most sophisticated model, KWMSS2, performed well, satisfying both global and local behaviors. KMSS2 also showed good structural stability, reproducing hydrographs regardless of the applied objective functions; however, superior parameter identifiability was not guaranteed. Numerous parameter sets could lead to indistinguishable hydrographs. This result supports that while making a model complex increases its performance accuracy and reduces its structural uncertainty, the model is likely to suffer from parameter uncertainty. The proposed model evaluation process can provide an effective guideline for identifying a reliable hydrologic model.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.17 no.8
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• pp.796-804
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• 1992

This paper presents a design of a backbone network which uses a rigister-Insertion ring structure, The introduction of a high speed register in sertton backbone ring enables high performance inter-network 4ommunicatlons In a simple and modular structure at low cost and Its concurrent communications.. Two or more bridge nodes can be used to construct a register Insertion backbone ring network. The high bandwidth of the backbone ring sup ports heavy traffic for Inter-segment Eornrnunicatlons. The bridge node does both local address filtering to block data entering the ring and remote address filtering to block data entering the local LAN segment . Title local address greatly reduces the rate on the backbone ring and the remote address filterlng greatly reduces the traffic rate on each LAN segment. An feature makes the network the network reconflguratlon simpler and transparent to users. A throughput analysis Is used to deterrune the bandwidth of the backbone rlr)g transmission medium.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.6
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• pp.367-374
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• 2000

This paper presents a method to fabricate freestanding structures by (100) silicon anisotropic etching and nickel electroless plating. The electroless plating process is simpler than the electroplating, and provides good coating uniformity and improved mechanical properties. Furthermore, the (100) silicon anisotropic etching in KOH solution with being aligned to <100> direction provides vertical (100) sidewalls on etched (100) surface. In this paper, the effects of the nickel electroless plating condition on the properties of electroless plated metal structures are investigated to apply fabrication of micro structures and then various micro structures are fabricated by nickel electroless plating. And then, the structures are released by silicon anisotropic etching in KOH solution with a large gap between the structure and the substrate. The fabricated cantilever structures are $210\mum$. wide, $5\mum$. thick and $15\mum$. over the silicon substrate, and the comb structure has the comb electrodes which are $4\mum$. wide and $4.3\mum$. thick separated by$1\mum$. It is released by silicon anisotropic etching in KOH solution. The gap between the structure and the substrate is $2.5\mum$.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.138-147
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• 2018

With the recent series of damage caused by earthquakes in Korea, such as Gyeongju and Pohang, we know that Korea is no longer a safe zone for earthquakes and that we need to be prepared for them. In addition, bridges built prior to the introduction of seismic design concepts remain without adequate seismic reinforcement measures, and earthquake reinforcement should be performed efficiently considering economic and structural safety. Preliminary assessment of seismic performance of existing bridges is divided into four seismic groups, taking into account seismicity, vulnerability and Impact, considering the magnitude of the existing bridge's seismic, and prioritization for further evaluation of seismic performance. In this study, unlike the existing anti-seismic reinforcement priority method, scores are calculated based on the seismic design criteria applied to bridges, importance coefficient of the bridge including the zone coefficient and the Importance, vulnerability index of the bridge including the soil condition and the elapsed years, detail coefficient of the bridge including the superstructure form, the span length, the width, the height, the design load, and the daily traffic volume. The calculated score items will be weighted and grouped according to the results. Using this, a simpler and more efficient algorithm was proposed to determine the priority of seismic reinforcement on a bridge.

• The Korean Journal of Pain
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• v.20 no.2
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• pp.148-153
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• 2007

Background: Complex regional pain syndrome (CRPS) is not regarded as an impairment in Korea. Guidelines for rating this impairment are under development by the Korean Academy of Medical Science based on that of the American Medical Association (AMA). However, no studies have been done on the validity of these guidelines in Korea. We therefore evaluated the validity of these guidelines using the criteria from the chapter on the central and peripheral nervous system (CNS-PNS class) and the worksheet for calculating total pain-related impairment score (TPRIS class). Methods: TPRIS and CNS-PNS classes were calculated through interviews of 28 CRPS patients. The correlation between the two classes was calculated. Results: TPRIS class and CNS-PNS class were well correlated (r = 0.593, P < 0.05). Conclusions: Both TPRIS or CNS-PNS classes were well correlated and could be used for evaluation of impairment. However, the CNS-PNS class is simpler and quicker to complete.

• The KIPS Transactions:PartD
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• v.15D no.5
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• pp.629-646
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• 2008

Because most metricsin the literatures are described by a natural language, they can be interpreted in an ambigous manner. To cope with this problem, there are some researches to express based on Object Constraint Language(OCL). Because OCL has been proposed to describe structural constraintsfor Unified Modeling Language(UML) diagrams, it is difficult and awkward. In this paper, we propose Metric Description Language(MDL) which is a high level language to describe metrics. MDL supports a modular description of complex metrics, aggregation function, and automatic navigation between entities. Moreover, we develop MetriUs for describing metrics using MDL and supporting an automated computation for UML diagrams. In a case study, we have described a variety of existing metrics using MDL and found that MDL contributes to producing simpler expression of metrics than OCL.

• Journal of Internet Computing and Services
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• v.4 no.4
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• pp.9-14
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• 2003

A GUI (graphical user interface) has been a dominant platform for HCI (human computer interaction). A GUI - based interaction has made computers simpler and easier to use. The GUI - based interaction, however, does not easily support the range of interaction necessary to meet users' needs that are natural. intuitive, and adaptive. In this paper, the modified BMA (block matching algorithm) is proposed to track a hand in a sequence of an image and to recognize it in each video frame in order to replace a mouse with a pointing device for a virtual reality. The HCI system with 30 frames per second is realized in this paper. The modified BMA is proposed to estimate a position of the hand and segmentation with an orientation of motion and a color distribution of the hand region for real - time processing. The experimental result shows that the modified BMA with the YCbCr (luminance Y, component blue, component red) color coordinate guarantees the real - time processing and the recognition rate. The hand tracking by the modified BMA can be applied to a virtual reclity or a game or an HCI system for the disable.

• Korean Journal of Remote Sensing
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• v.18 no.6
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• pp.359-367
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• 2002

In this paper, a new embedded wavelet packet image coder algorithm is proposed for an effective image coder using correlation between partitioned coefficients. This new algorithm presents parent-child relationship for reducing image reconstruction error using relations between individual frequency sub-bands. By parent-child relationship, every coefficient is partitioned and encoded for the zerotree data structure. It is shown that the proposed wavelet packet image coder algorithm achieves low bit rates and rate-distortion. It also demonstrates higher PSNR under the same bit rate and an improvement in image compression time. The perfect rate control is compared with the conventional method. These results show that the encoding and decoding processes of the proposed coder are simpler and more accurate than the conventional ones for texture images that include many mid and high-frequency elements such as aerial and satellite photograph images. The experimental results imply the possibility that the proposed method can be applied to real-time vision system, on-line image processing and image fusion which require smaller file size and better resolution.

• Korean Journal of Construction Engineering and Management
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• v.22 no.3
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• pp.31-39
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• 2021

The modular construction method is an off-site construction method using built-in structures from the manufacturing facilities. Modular construction is commonly applied to buildings which have relatively smaller and simpler structures than other types of buildings. Although modular building has emerged in the domestic construction industry as an alternative building strategy, previous researches on the environmental characteristics of modular building has not been comprehensively studied. Thus, this study empirically analyzed the insulation performance of thermal bridge and condensation parts of the modular buildings by using IR image analysis, Air-Surface Temperature Ratio method, and temperature difference ratio. The insulation performance analysis was conducted by comparing a modular building and a RC building in Seoul. The results shows that there was no significant difference between insulation performances of RC building and modular building. Furthermore

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.5
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• pp.380-388
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• 2019

Jet engine modulation(JEM) signals are widely used for target recognition. These signals coming from a potentially hostile aircraft provide specific information about the jet engine. In order to obtain the number of blades, which is uniquely provided by the JEM signal, one must extract the spool rate, which is the rotation speed of the blades. In this paper, we propose an algorithm to extract the spool rate from a weak JEM signal. A criterion is developed to extract the spool rate from the JEM signal by analyzing the intensity of the JEM signal component. The weak signal is first subjected to a high-pass filtering-based process, which modifies it to facilitate spool rate extraction. We then apply a peak detection process and extract the spool rate. The technique is simpler than the existing CEMD or WD method, is accurate, and greatly reduces the time required.