• Title/Summary/Keyword: Time-variant

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Stacked Autoencoder Based Malware Feature Refinement Technology Research (Stacked Autoencoder 기반 악성코드 Feature 정제 기술 연구)

  • Kim, Hong-bi;Lee, Tae-jin
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.4
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    • pp.593-603
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    • 2020
  • The advent of malicious code has increased exponentially due to the spread of malicious code generation tools in accordance with the development of the network, but there is a limit to the response through existing malicious code detection methods. According to this situation, a machine learning-based malicious code detection method is evolving, and in this paper, the feature of data is extracted from the PE header for machine-learning-based malicious code detection, and then it is used to automate the malware through autoencoder. Research on how to extract the indicated features and feature importance. In this paper, 549 features composed of information such as DLL/API that can be identified from PE files that are commonly used in malware analysis are extracted, and autoencoder is used through the extracted features to improve the performance of malware detection in machine learning. It was proved to be successful in providing excellent accuracy and reducing the processing time by 2 times by effectively extracting the features of the data by compressively storing the data. The test results have been shown to be useful for classifying malware groups, and in the future, a classifier such as SVM will be introduced to continue research for more accurate malware detection.

The Type Classification on Modifiable Styling Methods in Western Costumes - From Ancient to Middle Ages - (서양복식의 가변성 스타일링 유형분류 - 고대부터 중세까지를 중심으로 -)

  • Kim, Hye-Ree;Chun, Hei-Jung
    • Journal of the Korean Society of Costume
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    • v.62 no.2
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    • pp.1-12
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    • 2012
  • Cloths wrapped around the body have been the basis of the dress of people all over the world for centuries. This study is to research detailed modifiable fashion styling methods in history and to give ideas to people such as fashion professionals who are interested in fashion styling so that they can create modifiable fashion styling easily in fashion fields. The characteristics of modifiable fashion styling methods from ancient to middle ages are as follows. The first modifiable styling method is to expose the knots on the surface of the garments, and the knots were mainly located on the upper part of the body. The second method is a wrapping type of the modifiable styling method, which shows a lot of variant simple shapes of cloths. This method helped develop many wrapping methods over time. The third way is the fixed type of the modifiable styling method, and it uses accessories such as fibulae, belts to fix cloths, to create many different styles. The accessories are located on around either the neck or waist. The fourth method is the composite type of the modifiable styling methods mentioned above. This styling method is adapted in robe type clothes which makes the clothes look full of beautiful drapery. This study suggests that simple shapes of cloths can create enormous amount of styling which can be easily adapted and created nowadays.

Conformance-Based Dynamic Performance Optimization of an Actuator (순응도 기반의 구동기 동적 성능 최적화)

  • Son, Young-Kap
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.36 no.11
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    • pp.1327-1334
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    • 2012
  • This study shows the conformance-based design results of a fourth-order dynamic actuator showing a performance variation caused by variation in the components as well as aero-induced disturbances. The actuator comprises a BLDC motor, spur gear and worm gear assembly, and canard. The actuator performance was evaluated by using time-variant angle information of the canard. Based on the response surface models, critical system variables were screened using F-tests, and then, the performance was approximated as a function of the variables because it is difficult to determine the performance of a high-order dynamic system as a function of system variables through analytical approaches. In this study, the conformance of uncertain performance to the specification was defined as a probability measure. The design variables obtained by optimizing the measure can provide actuator performance conforming to the specifications considered, even though there is a variation in both the components and the aero-induced disturbances.

Isolation of Chemical Compounds from xBrassicoraphanus (배무채(xBrassicoraphanus)의 화학성분 분리)

  • Rhee, Yun-Hee;Ahn, Kyoo-Seok;Lee, Soo-Seong;Park, Young-Doo;Ryu, Shi-Yong;Kim, Sung-Hoon
    • Korean Journal of Pharmacognosy
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    • v.38 no.4
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    • pp.403-408
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    • 2007
  • xBrassicoraphanus is an intergenic breed crossed between Brassica campetris L. ssp. pekinensis and Raphanus sativus L. that have been daily consumed. xBrassicoraphanus was known to have good tastes and biological activities. Nevertheless, its constituetnts were not elucidated yet. Thus, in the present study, to indirectly evaluate the biological activity of xBrassicoraphanus, 12 compounds were isolated from leaves and roots of xBrassicoraphanus. On the basis of spectroscopic evidences, the structures of these compounds isolated from leaves of xBrassicoraphanus. were identified as ${\beta}-sitosterol$, indole-3-acetonitrile, ferulic acid, methyl ferulate, linolenic acid methyl ester, linolenic acid and coniferyl alcohol, while the chemical structures of compounds isolated from the roots of were xBrassicoraphanus were characterized as ${\beta}-sitosterol$, indole-3-acetonitrile, ferulic acid, methyl ferulate, linolenic acid methyl ester, 1-methoxyindole-3-acetonitrile, goitrin, 4-hydroxycinnamyl alcohol, coniferyl alcohol, palmitic acid and daucosterol. These can be classified as three steroids, two indole cyanides, two cinnamic acid derivatives, one cinnamyl alcohol derivative, three fatty acid derivatives one isothiocyanate. These results suggest that the compounds isolated from xBrassicoraphanus were almost identical with known components of Brassica campetris L. ssp pekinensis or Raphanus sativus L. However, it is necessary to investigate more about the difference of amounts of constituents according to harvest time and variant species amounts.

Performance Analysis of Multicast Relay Transmissions in WiMedia D-MAC for OSMU N-Screen Services (OSMU N-스크린 서비스를 위한 WiMedia D-MAC에서 멀티캐스트 릴레이 전송 기술의 성능 분석)

  • Hur, Kyeong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.12
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    • pp.2267-2273
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    • 2016
  • In this paper, WiMedia Distributed-MAC protocol is adopted for development of an OSMU (One Source Multi Use) N-screen wireless multicast service. But, when considering wireless communication environment where channel error rate is time-variant, N-screen high-speed data is vulnerable to be lost. For this problem, a multicast relay scheme is proposed by analyzing Distributed-MAC protocol. In proposed multicast relay scheme, Multicast-free DRP Availability IE is combined and the relay node suitable for N-screen multicast transmissions is selected. Through this operation, it can avoid wireless channel with high errors and can transmit N-screen high-speed data. In simulation results, the proposed multicast relay scheme is compared with conventional Distributed-MAC multicast scheme in view points of throughput and energy consumption according to various numbers of multicast nodes and BER (Bit Error Rate) values in wireless channel. Through simulation results, it is explained that proposed multicast relay scheme should be adopted in WiMedia Distributed-MAC protocol to realize OSMU N-screen wireless multicast services.

A study of Self-Tuning PI Speed Controller Based on Fuzzy for Permanent Magnet Linear Synchronous Motor (선형 영구자석형 동기 전동기의 Fuzzy 기반 Self-Tuning PI 속도 제어기에 관한 연구)

  • Lee Chin-Ha;Choi Cheol;Kim Cheul-U
    • The Transactions of the Korean Institute of Power Electronics
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    • v.9 no.6
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    • pp.602-611
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    • 2004
  • Servo system has commonly adapted PI controller with fixed gains, because of its simplicity and determinative relationship among the parameters. The fixed gains PI system may be applied well to some operation conditions, but not non-linearities, complex and time variant operation conditions. For solving these problems, another conventional method, 'variable gun schedule according to speed', is published. The value of gain is determined according to the absolute value of the mover real speed. In this paper, FSTPIC(Fuzzy Self-Tuning PI Controller) is proposed based on various experiences to rapidly reduce speed error and to secure a good speed response characteristics. The effectiveness of proposed algorithms is demonstrated by comparing to two conventional gain systems via 4-quadrant operation.

Pulmonary Giant Cell Carcinoma (폐에 발생한 거세포암종 -1 Case-)

  • 김현구;최영호;황재준;김욱진;김학제
    • Journal of Chest Surgery
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    • v.32 no.2
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    • pp.185-188
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    • 1999
  • The pulmonary giant cell carcinoma is classified as a variant of a large cell carcinoma and is diagnosed by the minimum component of 10% huge, pleomorphic and multinucleated giant tumor cell and emperipolesis of the neutrophils into the tumor cells. This tumor is characterized by local recurrences and early metastasis with extremely short patient survival. However, there are some reports that state that the survival time was extended by the operative resection and postoperative adjuvant chemotherapy and radiotherapy. A 46-year old male was admitted with complaint of hemoptysis for 2 months. Through chest X-ray and chest CT, a 5cm sized mass was found in the apical segment of the right upper lobe. During the preoperative evaluation, stenotic lesion in the left anterior descending coronary artery was found and treated by percutaneous transarterial coronary angioplasty. Four weeks later, right upper lobectomy was performed and the mass was proven to be a giant cell carcinoma. The patient received adjuvant chemotherapy and radiotherapy.

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Multistage Adaptive Partial PIC for CDMA System (CDMA 시스템을 위한 Multistage Adaptive Partial PIC)

  • Jeon Jae-Choon;Lee Bong-Hee;Hwang In-Kwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.1A
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    • pp.37-52
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    • 2004
  • In this paper, Multistage Adaptive Partial PIC eliminating effectively the multiple access and multipath interference for DS-CDMA based W-CDMA uplink system is designed and its performance is evaluated with computer simulation. By adaptively controlling the slope of the soft limiter with received signals, the efficiency of the soft limiter can be maximized and the better performance is obtained by solving error floor problem using further precise generation of interference signal. As a result, The proposed Multistage Adaptive Partial PIC with simple optimizing method for time-variant channel showed optimum performance at fewer stages. Besides fewer stages, the interference cancellation at the output of the rake receiver considerably reduced system complexity. The Multistage Adaptive Partial PIC with precise generation and efficient cancellation of interference signal can solve error eoor problem, resulted from initial false detection and improve system performance of high data rate system.

Active Vibration Control of a Cantilever Beam Using Fuzzy Control Scheme and PID Controller (퍼지 기법과 PID 제어기를 이용한 외팔보의 능동 진동 제어)

  • 최수영;김진태;박기헌
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.40 no.1
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    • pp.1-10
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    • 2003
  • This paper is concerned with the fuzzy control scheme and PID controller for the vibration suppression control of a cantilever beam equipped with a laser sensor and an electromagnetic actuator. The PID controller is being widely used in industrial applications. However, it is difficult to determine the appropriate PID gains in nonlinear systems and systems with time variant characteristic and so on. In this paper, we design the fuzzy based PID controller of which output gains are adjusted automatically and the designed controller is applied to active vibration control of a cantilever beam using electromagnetic actuator with strong nonlinearity. The tuning PID parameters of proposed controller are determined by using Fuzzy algorithm. Effectiveness and performance of the designed controller are verified by both simulation and experiment results. Experimental results demonstrate that better control performance can be achieved in comparison with the PID cotroller.

Development of a Storage-Reliability Estimation Method Using Quantal Response Data for One-Shot Systems with Low Reliability-Decreasing Rates (미소한 신뢰도 감소율을 가지는 원샷 시스템의 가부반응 데이터를 이용한 저장 신뢰도 추정방법 개발)

  • Jang, Hyun-Jeung;Son, Young-Kap
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.10
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    • pp.1291-1298
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    • 2011
  • This paper proposes a new reliability estimation method for one-shot systems using quantal response data, which is based on a parametric estimation method. The proposed method considers the time-variant failure ratio of the quantal response data and it can overcome the problems in parametric estimation methods. Seven reliability estimation methods in the literature were compared with the proposed method in terms of the accuracy of reliability estimation in order to verify the proposed method. To compare the accuracy of reliability estimation, the SSEs (Sum of Squared Error) of the reliability estimation results for the different estimation methods were evaluated according to the various numbers of samples tested. The proposed method provided more accurate reliability estimation results than any of the other methods from the results of the accuracy comparison.