• Title/Summary/Keyword: Design comparison

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An Experimental Study and Value Analysis for Performance Assessment of the Embo-thane Membrane Waterproofing Method (엘보탄도막방수공법의 성능평가를 위한실험적 연구 및 VE분석)

  • Yoon, Cha-Woong;Lee, Seung-Soo;Kim, Sang-Rok;Seo, Jong-Won
    • Korean Journal of Construction Engineering and Management
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    • v.10 no.5
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    • pp.123-134
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    • 2009
  • Since 1970s, urethane waterproofing method is broadly used in rooftops, underground spaces, and sports stadium for its outstanding ultraviolet blockage, watertightness, and elasticity. However, development of slippage-resistance and endurance, improvement of function considering convenience and visually pleasing of users, urethane waterproofing method is necessary, since rooftops and underground spaces have slippage and external force risks. Therefore, many improved waterproofing methods are being developed and, recently, embo-thane waterproofing method, which applies embo-spray coating system, has been developed. This paper explains exposure, nonexposure, and floor-material of embo-thane waterproofing method, and then perform experimental study for comparison with urethane waterproofing method about tensile strength, coefficient of expansion, performance of bond, anti-abrasion, and slippage-resistance. In addition, the performance index was presented for the superiority of embo-thane waterproofing method compared to urethane by setting up evaluation criteria considering not only physical performance but also design side of embo-thane waterproofing method, and Value Analysis applying AHP. Also for an assessment considering uncertain result, Monte Carlo Simulation Method was used to operate reliability analysis through statistic approach method.

Design of an Optimal Adaptive Filter for the Cancellation of M-wave in the EMG Controlled Functional Electrical Stimulation for Paralyzed Individuals (마비환자의 근전도제에기능적전기자극을 위한 M-wave 제거용 최적적응필터 설계)

  • Yeom Hojoon;Park Youngcheol;Lee Younghee;Yoon Youngro;Shin Taemin;Yoon Hyoungro
    • Journal of Biomedical Engineering Research
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    • v.25 no.6
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    • pp.479-487
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    • 2004
  • Biopotential signals have been used as command in systems using electrical stimulation of motor nerves to restore movement after an injury to the central nervous system (CNS). In order to use the voluntary EMG (electromyography) among the biopotentials as a control signal for the electrical stimulation of the same muscle for CNS injury patients, it is necessary to remove M-wave of having high magnitude from raw data. We designed an optimal filter for removing the M-wave and preserving the voluntary EMG and showed that the optimal filter is eigen filter. We also proved that the previous method using the prediction error filter(PEF) is a suboptimal filtering in the sense of preserving the voluntary EMG. On basis of the data obtained from a model for M-wave and voluntary EMG and from actual CNS injury patients, with false-positive rate analysis, the proposed adaptive filter showed a very promising performance in comparison with previous method.

A Study on Efficacy of Preemptive Analgesia - A Comparison on Efficacy of Preoperative and Postoperative Analgesic Administration - (선행적 진통 요법의 효과성에 대한 연구 -발치 전과 후 진통 요법의 효과 비교-)

  • Jung, Young-Soo;Kim, Moon-Key;Park, Hyung-Sik;Lee, Eui-Wung;Kang, Jeong-Wan
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.3 no.1 s.4
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    • pp.10-18
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    • 2003
  • Background: Studies on the pain have been dealing with many different ways for last several centuries. Especially, preemptive analgesia is being used as a method to control the postoperative pain. Many studies on its efficacy have been processed in different ways about various drugs, administration methods and times for various operations. And the value of preemptive analgesia are still controversial regarding the results of other clinical studies. The authors performed a clinical study on efficacy of preemptive analgesia using an non-steroidal anti-inflammatory drug (NSAID) for the surgical extraction of impacted third molar teeth and present the more effective pain treatment after oral surgery with literature review. Methods: Using a randomized double blind test design, this study compared the analgesic efficacies of an NSAID, Talniflumate 370 mg. This drug administrated first either 1 hour preoperatively (experimental group) or when the pain developed moderately to severely over 5 scale of verbal rating scales (0-10) to respective 30 patients undergoing the removal of impacted third molars. Pain intensity and the time from the end of surgery were assessed postoperatively whenever the patients demanded additional drug over 5 scale for forty eight hours using same verbal rating scales. Results: The sex distribution, the age of the patients. and the time required for surgery in two groups were similar. The average first time for demanding additional drug after surgery was 163.9 minutes in experimental group and 191.5 minutes in control group. At this time, the average pain intensity was 5.8 in experimental group and 6.1 in control group. And the average second time for demanding additional drug was 365.5 minutes in experimental group and 351.8 minutes in control group. At this time. the average pain intensities were 6.6 in experimental group and 6.2 in control group. No statistically significant difference was found between the average first times and second times, and the average pain intensities at first and second times in two groups. Conclusions: From these results the efficacy of preemptive analgesia used in this study was not appeared. This clinical study indicates that many NSAIDs administrated preoperatively in present practices have weak efficacy of preemptive analgesia for postoperative pain, thus the authors recommend that only postoperative analgesics are adequate without preoperative use of analgesics.

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A Design of Time-based Anomaly Intrusion Detection Model (시간 기반의 비정상 행위 침입탐지 모델 설계)

  • Shin, Mi-Yea;Jeong, Yoon-Su;Lee, Sang-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.5
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    • pp.1066-1072
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    • 2011
  • In the method to analyze the relationship in the system call orders, the normal system call orders are divided into a certain size of system call orders to generates gene and use them as the detectors. In the method to consider the system call parameters, the mean and standard deviation of the parameter lengths are used as the detectors. The attack of which system call order is normal but the parameter values are changed, such as the format string attack, cannot be detected by the method that considers only the system call orders, whereas the model that considers only the system call parameters has the drawback of high positive defect rate because of the information obtained from the interval where the attack has not been initiated, since the parameters are considered individually. To solve these problems, it is necessary to develop a more efficient learning and detecting method that groups the continuous system call orders and parameters as the approach that considers various characteristics of system call related to attacking simultaneously. In this article, we detected the anomaly of the system call orders and parameters by applying the temporal concept to the system call orders and parameters in order to improve the rate of positive defect, that is, the misjudgment of anomaly as normality. The result of the experiment where the DARPA data set was employed showed that the proposed method improved the positive defect rate by 13% in the system call order model where time was considered in comparison with that of the model where time was not considered.

A Study on Comparison of the Color Characteristics in Traditional Houses between South Korea and China - Focused on the Korean Folk Village Upper-class No.22 and Beijing Si-He-Yuan - (한.중 전통주택의 색채특성에 관한 비교연구 - 민속촌 양반가 22호와 북경 사합원을 중심으로 -)

  • Yeo, Hwa-Sun;Suh, Joo-Hwan;Zhu, Lin
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.28 no.3
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    • pp.53-59
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    • 2010
  • This paper mainly focuses on the Korean Folk Village and Beijing Si-He-Yuan, according to the color theory of hue, value and chroma of Munsell color system to demonstrates the similarities and differences of the traditional upper-class housing between South Korea and China. As the neighboring countries sharing very similar culture and philosophy which owe to the continual communications between China and Korea in the history. The Obangsaek which is derived from the thought of five-elements profoundly and deeply impact on the color selection of traditional housing in both countries. According to the quantitative analysis of photographs, it was found that: 1. The commonly used colors in Korea are Y, YR and neutral color, but in China, people usually used R and GY, especially the high chroma red in Beijing Si-He-Yuan was used as a symbolic color. 2. The chroma preference of traditional housing reveals that people in China used to apply the polychrome and various brightness, on the contrary, the color of low chroma and high lightness were used to be applied in Korea which can give the sense of simplicity and tranquility. 3. Red, one of the Obangsaek affects the color characteristic of Beijing Si-He-Yuan critically but scarcely impact on the color characteristic of Korean Folk Village.

Research on Gas Injection Mold using CAE Analysis of Steering wheel Parts (자동차핸들 제품의 CAE해석을 활용한 가스 사출성형에 관한연구)

  • Kang, Sae-Ho;Woo, Chang-Ki;Kim, Ok-Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.11
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    • pp.7729-7735
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    • 2015
  • As plastic injection mold parts is suitable system mass production making mold. So thick steering wheel parts is desirable to carry out gas injection molding. Gas injection mold is skill to inject nitrogen gas postfilling melting raw material into mold. Gas injection mold have many advantage like retrenchment of material cost, upgrading the guality. etc. It was decided gate position to minimize warpage of parts analysis injection mold process using mold flow software and incase doing gas injection mold using normal p.p material. it occur big warpage. so it is object minimizing warpage of injection parts to change p.p material containing mineral 18% and removing fingering phenomenon trouble as changing gate position. Also in case carrying out gas injection mold, I did comparison and analysis to grasp shape flow in gas setting a standard gate after flowing in raw material. Through this study, I found out changing of thickness by parts shape and it can occur warpage of parts by plastic material even though it carry out gas injection mold and it had a direct influence on trouble of parts by gate position.

Energy Efficient Distributed Intrusion Detection Architecture using mHEED on Sensor Networks (센서 네트워크에서 mHEED를 이용한 에너지 효율적인 분산 침입탐지 구조)

  • Kim, Mi-Hui;Kim, Ji-Sun;Chae, Ki-Joon
    • The KIPS Transactions:PartC
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    • v.16C no.2
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    • pp.151-164
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    • 2009
  • The importance of sensor networks as a base of ubiquitous computing realization is being highlighted, and espicially the security is recognized as an important research isuue, because of their characteristics.Several efforts are underway to provide security services in sensor networks, but most of them are preventive approaches based on cryptography. However, sensor nodes are extremely vulnerable to capture or key compromise. To ensure the security of the network, it is critical to develop security Intrusion Detection System (IDS) that can survive malicious attacks from "insiders" who have access to keying materials or the full control of some nodes, taking their charateristics into consideration. In this perper, we design a distributed and adaptive IDS architecture on sensor networks, respecting both of energy efficiency and IDS efficiency. Utilizing a modified HEED algorithm, a clustering algorithm, distributed IDS nodes (dIDS) are selected according to node's residual energy and degree. Then the monitoring results of dIDSswith detection codes are transferred to dIDSs in next round, in order to perform consecutive and integrated IDS process and urgent report are sent through high priority messages. With the simulation we show that the superiorities of our architecture in the the efficiency, overhead, and detection capability view, in comparison with a recent existent research, adaptive IDS.

Evaluation on the Horizontal Shear Strength of Precast Concrete Slab with the Inverted-Rib-Plus (리브플러스 PC슬래브의 수평전단강도 평가)

  • Park, Keum Sung;Lee, Sang Sup;Choi, Yun Cheul
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.6
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    • pp.156-165
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    • 2011
  • This study investigates the horizontal shear behavior of an interface between precast concrete (PC) and topping concrete(RC), and evaluates the horizontal based on the investigations by the experimental. Horizontal shear strength in connected surface is determined by the roughness an interface and the shear reinforcement or not. In this study, the main experimental parameters are the shear reinforcement types in the shape of loop-type and lattice-type, rebar spacing. A total of four specimens were shear strength tested and manufactured. As a result, the horizontal shear strength of reinforced connected surface was found to be controlled by deformation in vertical direction. Comparison of reinforcement shape, the mean initial crack load loop type specimens, the average maximum load and the junction of the average in terms of initial stiffness, respectively 33.7%, 45.9% and 55.2% were large enough. Evaluation results for shear strength equation of existing standard domestic, the loop-type reinforced 2.32 to 4.23 times, lattice-type reinforced 1.65 to 3.06 times appears to be higher. Behavior of interface or strength of structural design criteria was fairly safe side. It does not have any problems in the applied field is considered.

Soil Water Characteristic Curve of the Weathered Granite Soil through Simulated Rainfall System and SWCC Cell Test (강우재현 모형실험과 SWCC Cell 실험에 의한 화강암질 풍화토의 함수특성곡선)

  • Ki, Wan-Seo;Kim, Sun-Hak
    • The Journal of Engineering Geology
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    • v.18 no.4
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    • pp.523-535
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    • 2008
  • A simulated rainfall system was built, and the unsaturated characteristics were examined by execution of simulated rainfall system test and soil water characteristic curve cell test(SWCC Cell Test) under the various rainfall and slope conditions. With the results, the applicability of infiltration behavior under rainfall and soil water characteristic curve models to the unsaturated weathered granite soil was examined. At the results of comparison the volumetric water content and matric suction measured in the wetting process(under rainfall) with those in the drying process(leaving as it was) of the simulated rainfall system, the volumetric water content showed a difference of $2{\sim}5%$ and matric suction of about $3{\sim}10\;kPa$, indicating the occurrence of hysteresis. In addition, the difference was relatively larger in matric suction than in the volumetric water content, and this tells that the hysteresis behavior is larger in matric suction. When the soil water characteristic curve derived from measurements in simulated rainfall system test were compared with those from the soil water characteristic curve cell test, both methods produced soil water characteristic curves close each other in the wetting process and the drying process, but in both, there was a difference between results obtained from in the wetting process and those from in the drying process. Thus, when soil water characteristic curves are rationally applied to the design and stability analysis considering of the properties of unsaturated soil, it is considered desirable to apply the soil water characteristic curve of the wetting process to the wetting process, and that of the drying process to the drying process.

A Reconstruction of Probability Unit of Elementary Mathematics Textbook Based on Freudenthal's Reinvention Method (Freudenthal의 재발명 방법에 기초한 제7차 초등수학교과서 확률 단원 재구성)

  • Kang, Ho-Jin;Kang, Heung-Kyu
    • Journal of Elementary Mathematics Education in Korea
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    • v.12 no.1
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    • pp.79-100
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    • 2008
  • Freudenthal has advocated the reinvention method. In that method, the pupils start with a meaningful context, not ready-made concepts, and invent informative method through which he could arrive at the formative concepts progressively. In many face the reinvention method is contrary to the traditional method. In traditional method, which was named as 'concretization method' by Freudenthal, the pupils start with ready-made concepts, and applicate this concepts to various instances through which he could arrive at the understanding progressively. Through analysis, it turns out that Korea's seventh elementary mathematics textbook is based on concretization method. In this thesis, first of all, I will reconstruct probability unit of seventh elementary textbook according to Freudenthal's reinvention method. Next, I will perform teaching experiment which is ruled by new lesson design. Lastly, I analysed the effects of teaching experiment. Through this study, I obtained the following results and suggestions. First, the reinvention method is effective on the teaching of probability concept and algorithm. Second, in comparison with current textbook strand, my strand which made probability concept go ahead and combinatorics concept let behind is not deficiency. Third, tree diagram is effective matrix which contribute to formalization of combinatorics calculation. Lastly, except for fraction, diverse representation of probability, for example percentage or informal ratio expression must be introduced in teaching process.

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