• Title/Summary/Keyword: dynamic modification

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Insect Adaptations to Changing Environments - Temperature and Humidity

  • Singh, Tribhuwan;Bhat, Madan Mohan;Khan, Mohammad Ashraf
    • International Journal of Industrial Entomology and Biomaterials
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    • v.19 no.1
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    • pp.155-164
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    • 2009
  • The most important factors in environment that influence the physiology of insects are temperature and humidity. Insects display a remarkable range of adaptations to changing environments and maintain their internal temperature (thermoregulation) and water content within tolerable limits, despite wide fluctuations in their surroundings. Adaptation is a complex and dynamic state that widely differs in species. Surviving under changing environment in insects depends on dispersal, habitat selection, habitat modification, relationship with ice and water, resistance to cold, diapause and developmental rate, sensitivity to environmental signals and syntheses of variety of cryoprotectant molecules. The mulberry silkworm (Bombyx mori) is very delicate and sensitive to environmental fluctuations and unable to survive naturally because of their domestication since ancient times. Thus, the adaptability to environmental conditions in the silkworm is quite different from those of wild insects. Temperature, humidity, air circulation, gases and photoperiod etc. shows a significant interaction in their effect on the physiology of silkworm depending upon the combination of factors and developmental stage affecting growth, development, productivity and quality of silk. An attempt has been made in this article to briefly discuss adaptation in insects with special emphasis on the role of environmental factors and their fluctuations and its significance in the physiology of mulberry silkworm, B. mori.

Korean Innovation Model: Toward a New Horizon (한국의 기술혁신모형: 새로운 지평을 향하여)

  • Choe Yeong Rak;Lee Dae Hui;Song Yong Il;Jeong Yun Cheol
    • Journal of Technology Innovation
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    • v.13 no.1
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    • pp.247-263
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    • 2005
  • Prior research in R8ED innovation in Korea has been centered around the 'three-stage development model,' which hypothesizes that the Korean innovation process goes from the introduction (of foreign technology) stage, through assimilation stage to the final modification stage. As Korean economy shifts from traditional industry-led development to innovation-centric development, such an approach loses sight of the whole picture. The current study argues that a new framework is required for adequate analysis on newly arising innovative patterns in Korea, emphasizing source technology development and technology leader strategy. For this purpose, we propose the 'Jigsaw Puzzle Model' of technology development, which is then verified by an in-depth analysis on the innovation processes of 3 representative IT products of Korea, DRAM, TH LCD, and CDMA. The model suggests that Korean innovation model is a dynamic, efficient amalgamation of foreign-acquired and dependent technologies, based on internally accumulated technological resources. The model explains better how Korean firms are achieving a rapid catch-up of technological gaps with advanced nations and are able to transfer from the technology follower to the leader position.

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A Study on the Modification of Frequency Detection Position for Frequency Source in HVDC System Using of AC Voltage (AC전압을 이용한 HVDC 시스템의 주파수 신호원 검출위치 변경에 관한 연구)

  • Park, Jong-Kwang;Kim, Chan-Ki;Yang, Byeong-Mo;Jung, Gil-Jo;Han, Byoung-Sung
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.19 no.6
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    • pp.100-108
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    • 2005
  • In this paper deals with the frequency control of the HVDC scheme linking Haenam to Cheju Island. The primary aim of the study is to develop and evaluate a new frequency control that can be employed without having to utilise the existing Synchronous Compensators(Gas Turbines). Transient condition studies are performed utilising the detailed control strategies for the HVDC link, implemented in PSCAD/EMTDC. Study cases are completed involving synchronous compensators trip and load ripping events and study plots presented. It is demonstrated that the existing frequency measurement can be replaced by one derived from the AC network alone, incorporated into a new frequency control algorithm and gives effective frequency control and dynamic performance.

A Study on the Reduction of Maximum Complexity in SOLA Algorithm for Real Time Implementation (실시간 구현을 위한 SOLA 알고리즘의 계산량 감소에 관한 연구)

  • Ham MyungKyu;Jung HyunUk;Bae MyungJin
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.101-104
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    • 2004
  • 음성속도변환(TSM : Time Scaling Modification) 알고리즘은 시간축에서 음성 신호의 속도를 변환할 수 있는 방식이다. 이러한, 방법으로는 OLA(Overlap Add), SOLA (Synchronized Overlap Add) 알고리즘 등이 연구 되어 왔다. 2 가지 방식 중에도 동기화를 시켜 overlap 을 시키는 SOLA 알고리즘이 OLA 방법에 비해 음질이 우수하다. 본 논문에서는 TMS320C5416 DSP 에 계산량이 감소된 SOLA 알고리즘을 실시간 구현하였다. 기존의 SOLA 알고리즘에서 동기화를 위해 사용하고 있는 cross-correlation 함수는 곱셈연산에서 발생하는 bit 의 dynamic range 가 커서 나눗셈 연산에서도 과도한 연산량을 필요로 한다. 따라서 이러한 계산량의 감소를 위해 기존의 cross-correlation 함수가 대신 더하기와 빼기의 연산으로 수행되는 NAMDF 함수를 사용하여 계산량을 줄였다. 제안한 방법을 SOLA 알고리즘에 적용하여 성능 평가를 실시하였다. TMS320C5416 DSP 에 실시간으로 실험한 결과 NAMDF 함수를 사용하였을 경우 음질의 저하가 거의 없었으며, 계산량을 기존의 cross-correlation 방식에 비해 6.22MIPS 가까이 감소시킬 수 있었다.

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Design and Implementation of Security Frame work for Application Server with Components

  • 김행곤;강전근
    • Journal of the Korea Computer Industry Society
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    • v.5 no.4
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    • pp.531-540
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    • 2004
  • Development of Web service application requires the interoperability between various heterogeneous systems, extensibility to allow modification of business environment not of user interface, maintainability, flexibility and reusability As the properties of CBD (Component Based Development) have gradually become clear, attention has started to turn the smooth technology and methodology to solve the existing problems and issues the dynamic responds for the distributed web environments. In this paper, we identify some of the major architectural affecting CBD and describe the Design and Implementation of Security Framework for Application Server with Components. We identify the candidate components, model it using UML and layer it on the architecture. The frameworks will Provide the various security functions, such as incorporating with legacy security systems, supporting of J2EE, JAAS and Kerberos and assisting in increasing the tailorability of component.

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ARP Modification for Prevention of IP Spoofing

  • Kang, Jung-Ha;Lee, Yang Sun;Kim, Jae Young;Kim, Eun-Gi
    • Journal of information and communication convergence engineering
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    • v.12 no.3
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    • pp.154-160
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    • 2014
  • The address resolution protocol (ARP) provides dynamic mapping between two different forms of addresses: the 32-bit Internet protocol (IP) address of the network layer and the 48-bit medium access control (MAC) address of the data link layer. A host computer finds the MAC address of the default gateway or the other hosts on the same subnet by using ARP and can then send IP packets. However, ARP can be used for network attacks, which are one of the most prevalent types of network attacks today. In this study, a new ARP algorithm that can prevent IP spoofing attacks is proposed. The proposed ARP algorithm is a broadcast ARP reply and an ARP notification. The broadcast ARP reply was used for checking whether the ARP information was forged. The broadcast ARP notification was used for preventing a normal host's ARP table from being poisoned. The proposed algorithm is backward compatible with the current ARP protocol and dynamically prevents any ARP spoofing attacks. In this study, the proposed ARP algorithm was implemented on the Linux operating system; here, we present the test results with respect to the prevention of ARP spoofing attacks.

The Homeobox and Genetic Disease: Structure and Dynamics of Wild Type and Mutant Homeodomain Proteins

  • Ferretti, James A.
    • BMB Reports
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    • v.34 no.1
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    • pp.1-7
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    • 2001
  • Structural and physical properties of type wild type and various selected mutants of the vnd/NK-2 homeodomain, the protein product of the homeobox, and the implication in genetic disease are reviewed. The structure, dynamics and thermodynamics have been Investigated by NMR and by calorimetry. The interactions responsible for the nucleotide sequence-specific binding of the homeodomain to its consensus DNA binding site have been identified. There is a strong correlation between significant structural alterations within the homeodomain or its DNA complex and the appearance of genetic disease. Mutations in positions known to be important in genetic disease have been examined carefully For example, mutation of position 52 of vnd/NK-2 results in a significant structural modification and mutation of position 54 alters the DNA binding specificity and amity The $^{15}N$ relaxation behavior and heteronuclear Overhauser effect data was used to characterize and describe the protein backbone dynamics. These studies were carried out on the wild type and the double mutant proteins both in the free and in the DNA bound states. Finally, the thermodynamic properties associated with DNA binding are described for the vnd/NK-2 homeodomain. These thermodynamic measurements reinforce the hypothesis that water structure around a protein and around DNA significantly contribute to the protein-DNA binding behavior. The results, taken together, demonstrate that structure and dynamic studies of proteins combined with thermodynamic measurements provide a significantly more complete picture of the solution behavior than the individual studies.

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A Study on Structural Design and Evaluation of the High Precision Cam Profile CNC Grinding Machine (고 정밀 캠 프로파일 CNC 연삭기의 구조설계 및 평가에 관한 연구)

  • Lim, Sang-Heon;Shin, Sang-Hun;Lee, Choon-Man
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.10
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    • pp.113-120
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    • 2006
  • A cam profile CNC grinding machine is developed for manufacture of high precision contoured cams. The developed machine is composed of the high precision spindle using boll bearings, the high stiffness box layer type bed and the three axis CNC controller with the high resolution AC servo motor. In this paper, structural and modal analysis for the developed machine is carried out to check the design criteria of the machine. The analysis is carried out by FEM simulation using the commercial software, CATIA V5. The machine is modeled by placing proper shell and solid finite elements. And also, this paper presents the measurement system and experimental investigation on the modal analysis of a grinding machine. The weak part of the machine is found by the experimental evaluation. The results provide structure modification data for good dynamic behaviors. And safety of the machine was confirmed by the modal analysis of modified machine design. Finally, the cam profile grinding machine was successfully developed.

Running Bucket Vibration Test of Steam Turbines (증기 터빈 버킷의 회전 진동 시험)

  • 박종포;신언탁;김호종
    • Journal of KSNVE
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    • v.8 no.2
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    • pp.331-335
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    • 1998
  • A design modification was made on the 9-th stage wheel dovetail of a high-intermediate pressure (HIP) turbine rotor for a fossil power plant that necessitates the use of new long-shank buckets for the row. A bucket vibration test is necessary to verify that the new 9-th stage buckets have adequate frequency margin from a nozzle passing frequency when running at speed. A finite element analysis (FEA) has been performed using a commercial S/W to approximately estimate bucket natural frequencies, and thus to help the vibration test. A row of the new buckets has assembled on the HIP rotor for the vibration tests using dynamic balancing facilities. The tests have been done during deceleration run with air excitation. The test results are compared with the calculation using our empirical formula, and show that the modified design meets the frequency-margin requirements.

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A Study on the Dynamic Characteristics of Composite Deck Plate According to the Modification of Boundary Conditions (경계조건의 조절에 따른 합성 데크플레이트 슬래브의 거동특성에 관한 연구)

  • 김우영;정은호;엄철환;김희철
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1998.04a
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    • pp.371-376
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    • 1998
  • As the requirement of high-rise buildings in big cities increases, steel structural system becomes more popular in spite of the relatively higher material cost compared to that of the concrete structural system. Most of the steel structure adopts metal deck floor system because of the easiness in construction. However, the metal deck floor system has a weakness on vibration which became very important factor in office buildings, hotels and residential buildings as the more sensitive machines being used. Therefore, most, of the building codes in many countries restrict the natural frequency of the each floor should be higher than or equal to 15 Hz. Floor vibration of the KEM deck composite floor system which has been , developed recently from the engineers and scientists in Korea was measured. Also, the simplified analytical derivation of natural frequency for each floor was studied according to the measured natural frequency for each different boundary condition of the floor. As the length of the slab gets bigger, the natural frequency of the slab becomes lower even though the structural designer still considers it as a one-way slab.

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