• 제목/요약/키워드: Dynamic alteration

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DVR 모니터의 동특성 향상을 위한 구조 개선에 관한 연구 (Design Alteration of a Security DVR Monitor Structure for the Improved Dynamic Stabilty)

  • 김건형;이원규;이태훈;노승훈;정평수
    • 한국산업융합학회 논문집
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    • 제13권2호
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    • pp.63-68
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    • 2010
  • Structural vibrations are among the biggest concerns in developing high resolution DVR(Digital Video Recorder) monitors. The vibrations in DVR monitors are mostly originated from the excitation sources such as the HDD and the cooling fan. In this study, the vibrations generated from the excitation sources were investigated in order to analyze the individual effect on the structural vibrations of the monitors and further to establish the design alteration to suppress the vibrations for the stability of the structure and for the better quality of the screen. The result shows that relatively simple design alterations can improve the stability of the structure substantially.

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DNP 제어기에 의한 비선형 동적 매니퓰레이터 제어 (Nonlinear Dynamic Manipulator Control Using DNP Controller)

  • 조현섭;김희숙;유인호;장성환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 B
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    • pp.764-767
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    • 1999
  • In this paper, to bring under robust and accurate control of auto-equipment systems which disturbance, parameter alteration of system, uncertainty and so forth exist, neural network controller called dynamic neural processor(DNP) is designed. Also, the architecture and learning algorithm of the proposed dynamic neural network, the DNP, are described and computer simulations are provided to demonstrate the effectiveness of the proposed learning method using the DNP.

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Spatio-temporal Dynamic Alteration of Forest Canopy Density based on Site Associated Factor: View from Tropical Forest of Nepal

  • Panta, Menaka;Kim, Kye-Hyun
    • 대한원격탐사학회지
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    • 제22권5호
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    • pp.313-323
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    • 2006
  • Forest Canopy Density is a dynamic process mediated by various natural and anthropogenic factors. It can be changed over time and locations in the same forest type and landscape. However, human dimensions are considered as the primary force of landscape change and subsequent forest canopy loss in tropical regions of the world. Many studies have been indicated that roads have a far greater impact on forests than simply allowing access for human use. Similarly, rivers have been used as means of transportation, hence illegal logging and felling further deplete forest canopy density. The main objective of this study was to investigate the spatio-temporal dynamic alterations of Forest Canopy Density (FCD) across with site associated factors such as biophysical, physical and human interferences in tropical region of Nepal from 1988 to 2001. Landsat TM and ETM+ of 1988 and 2001 were used to assess the spatial and temporal dynamic alterations of FCD. This analysis revealed that distance to human settlements at P=<0.01, rivers, human interferences (path and fire) and species composition had a statistically significance at P=<0.05 level. However, other factors did not show any significant relation. So, we concluded that understanding of dynamic alterations of FCD with respect to factors was quite complex phenomena. Other surrounding environment could also playa significant role. A comprehensive analysis could be required to understand such complexities. Therefore, additional factors such as climatic, biophysical, social, and institutional with respect to spatio-temporal variability should be considered for the better understanding of canopy dynamic.

Dynamic behavior of clayey sand over a wide range using dynamic triaxial and resonant column tests

  • Guler, Ersin;Afacan, Kamil B.
    • Geomechanics and Engineering
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    • 제24권2호
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    • pp.105-113
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    • 2021
  • Deformations in soils induced by dynamic loads cause damage to the structures above the soil layers. It is important for geotechnical engineering practice that how the soil behaves due to repeated loads and the necessary precautions to be taken accordingly. Turkey is one of the most important seismic regions in Europe and earthquake studies to be conducted in this area are intended to reduce the damage as a result of taking the necessary measures. To determine the properties of soils under dynamic loads, stress-controlled dynamic triaxial and resonant column tests can be performed. In this study, these experiments were implemented in the laboratory on the clayey sand soil samples obtained from Bilecik Söğüt. To evaluate the effects of the confining pressure and rate of loading on the dynamic behavior of soils, samples were dynamically loaded by different rates at varying confining pressures. As a result, the changes in stress-strain properties of soils under dynamic loads were investigated. The alteration in behavior in terms of modulus reduction and damping ratios was obtained to vary a lot with the change of the lateral pressure on soil along with the frequency of the load.

Why Dynamic Security for the Internet of Things?

  • Hashemi, Seyyed Yasser;Aliee, Fereidoon Shams
    • Journal of Computing Science and Engineering
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    • 제12권1호
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    • pp.12-23
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    • 2018
  • The Internet of Things (IoT) ecosystem potentially includes heterogeneous devices with different processing mechanisms as well as very complicated network and communication models. Thus, analysis of data associated with adverse conditions is much more complicated. Moreover, mobile things in the IoT lead to dynamic alteration of environments and developments of a dynamic and ultra-large-scale (ULS) environment. Also, IoT and the services provided by that are mostly based on devices with limited resources or things that may not be capable of hosting conventional controls. Finally, the dynamic and heterogeneous and ULS environment of the IoT will lead to the emergence of new security requirements. The conventional preventive and diagnostic security controls cannot sufficiently protect it against increasing complication of threats. The counteractions provided by these methods are mostly dependent on insufficient static data that cannot sufficiently protect systems against sophisticated and dynamically evolved attacks. Accordingly, this paper investigates the current security approaches employed in the IoT architectures. Moreover, we define the dynamic security based on dynamic event analysis, dynamic engineering of new security requirements, context awareness and adaptability, clarify the need for employment of new security mechanism, and delineate further works that need to be conducted to achieve a secure IoT.

일체형 컴퓨터의 구조 안정화를 위한 설계 개선 (Design Alteration of a All in One PC for the Improved Stability)

  • 김동욱;노승훈;김건형;양용준
    • 한국기계가공학회지
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    • 제12권6호
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    • pp.109-116
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    • 2013
  • Vibrations are generally recognized as the biggest concern in maintaining part' longevity of an All-in-one PC. The vibrations in PCs originate from excitation sources such as the HDD and the cooling fan. In this study, the vibrations from these sources were investigated in order to analyze the individual effects of the parameters on the structural vibrations of the PC; further, we attempted to establish design alterations that could successfully suppress vibrations, in order to achieve improved stability and part' longevity. The results show that relatively simple design alterations can substantially improve the stability of PCs.

Dynamic Configuration and Operation of District Metered Areas in Water Distribution Networks

  • Bui, Xuan-Khoa;Kang, Doosun
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2021년도 학술발표회
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    • pp.147-147
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    • 2021
  • A partition of water distribution network (WDN) into district metered areas (DMAs) brings the efficiency and efficacy for water network operation and management (O&M), especially in monitoring pressure and leakage. Traditionally, the DMA configurations (i.e., number, shape, and size of DMAs) are permanent and cannot be changed occasionally. This leads to changes in water quality and reduced network redundancy lowering network resilience against abnormal conditions such as water demand variability and mechanical failures. This study proposes a framework to automatically divide a WDN into dynamic DMA configurations, in which the DMA layouts can self-adapt in response to abnormal scenarios. To that aim, a complex graph theory is adopted to sectorize a WDN into multiscale DMA layouts. Then, different failure-based scenarios are investigated on the existing DMA layouts. Here, an optimization-based model is proposed to convert existing DMA layouts into dynamic layouts by considering existing valves and possibly placing new valves. The objective is to minimize the alteration of flow paths (i.e., flow direction and velocity in the pipes) while preserving the hydraulic performance of the network. The proposed method is tested on a real complex WDN for demonstration and validation of the approach.

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Metabolomic Investigation on Fermentation Products of Achyranthes japonica Nakai by Lactobacillus plantarum

  • Lee, Chang-Wan;Lee, Do Yup
    • Journal of Microbiology and Biotechnology
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    • 제30권3호
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    • pp.378-381
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    • 2020
  • Fermentation has recently re-emerged as an approach for improved functionality of food products in addition to the traditional roles such as shelf life, taste, and texture. Here, we report dynamic changes in the metabolite profiles of Achyranthes japonica Nakai by Lactobacillus plantarum fermentation, primarily, the significant increases in representative functional ingredients, 20-hydroxyecdysone and 25S-inokosterone. Additionally, untargeted metabolite profiling showed 58% of metabolites underwent significant alteration. The most dynamic change was observed in cellobiose, which showed a 56-fold increase. Others were sugar alcohols and amino acids, while lyxitol and erythritol that were among the most dynamically down-regulated.

컴퓨터 그래픽스에 의한 이원 분산분석 (Computer graphics approach to two-way ANOVA)

  • 허문열
    • 응용통계연구
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    • 제8권1호
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    • pp.75-87
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    • 1995
  • 데이터 분석 과정에서 일부 데이터를 변화시키거나 또는 적용하고자 하는 통계적 모형의 성격을 변화시킬 때 이러한 변화가 분석 결과에 어떤 영향을 미치는가를 즉시에 알아보기 위해 동적그래픽스의 기법을 이용한다. 본 논문에서는 분산분석 과정을 동적그래픽스로 구현하는 방법과 이를 구현하는데 필요한 여러가지 형태의 플롯을 설명하고 이원 분산분석 모형에서 구현한 동적그래픽스 소프트웨어를 소개한다.

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NEW METHODS OF THE GROWING COMPLICATED SHAPED SAPPHIRE PRODUCTS: VARIABLE SHAPING TECHNIQUE AND LOCAL DYNAMIC SHAPING TECHNIQUE

  • Borodin, V.A.;Sidorov, V.V.;Steriopolo, T.A.
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1999년도 PROCEEDINGS OF 99 INTERNATIONAL CONFERENCE OF THE KACG AND 6TH KOREA·JAPAN EMG SYMPOSIUM (ELECTRONIC MATERIALS GROWTH SYMPOSIUM), HANYANG UNIVERSITY, SEOUL, 06월 09일 JUNE 1999
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    • pp.209-225
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    • 1999
  • Detailed description of the crystal growth methods permitting one to obtain complicated shape crystals from the melt is given. The variable shaping technique provides the growth of crystals with a discrete altering cross-section configuration during crystallization. The dynamic local shaping technique enables one to grow items with a continuous alteration of the side surface profile by a preset program.

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