• Title/Summary/Keyword: embedding conditions

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A study on the hydro-embedding technology in the tube hydroforming process (하이드로포밍 공정을 이용한 무용접 부품체결 기술개발에 관한 연구)

  • 김동규;박광수;안익태;한수식;문영훈
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2003.10a
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    • pp.241-244
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    • 2003
  • The productivity of hydroforming process can be increased by combining pre-forming process and post-forming process such as the bending, piercing and the embedding process. Therefore in this study, integrated studies on the hydro-embedding technology have been performed by analyzing the deformed mode of the tubes and the optimal process parameters. In the case of the embedding test the characteristics of the embedded parts, such as the shape of the screw tip, screw thread and shape of thread were investigated at various process conditions. To measure the clamping force between the embedded part and the tube, special measuring device was used.

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Virtual Network Embedding through Security Risk Awareness and Optimization

  • Gong, Shuiqing;Chen, Jing;Huang, Conghui;Zhu, Qingchao;Zhao, Siyi
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.7
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    • pp.2892-2913
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    • 2016
  • Network virtualization promises to play a dominant role in shaping the future Internet by overcoming the Internet ossification problem. However, due to the injecting of additional virtualization layers into the network architecture, several new security risks are introduced by the network virtualization. Although traditional protection mechanisms can help in virtualized environment, they are not guaranteed to be successful and may incur high security overheads. By performing the virtual network (VN) embedding in a security-aware way, the risks exposed to both the virtual and substrate networks can be minimized, and the additional techniques adopted to enhance the security of the networks can be reduced. Unfortunately, existing embedding algorithms largely ignore the widespread security risks, making their applicability in a realistic environment rather doubtful. In this paper, we attempt to address the security risks by integrating the security factors into the VN embedding. We first abstract the security requirements and the protection mechanisms as numerical concept of security demands and security levels, and the corresponding security constraints are introduced into the VN embedding. Based on the abstraction, we develop three security-risky modes to model various levels of risky conditions in the virtualized environment, aiming at enabling a more flexible VN embedding. Then, we present a mixed integer linear programming formulation for the VN embedding problem in different security-risky modes. Moreover, we design three heuristic embedding algorithms to solve this problem, which are all based on the same proposed node-ranking approach to quantify the embedding potential of each substrate node and adopt the k-shortest path algorithm to map virtual links. Simulation results demonstrate the effectiveness and efficiency of our algorithms.

Large-eddy simulation of channel flow using a spectral domain-decomposition grid-embedding technique (스펙트럴 영역분할 격자 삽입법을 이용한 채널유동의 큰 에디 모사)

  • Gang, Sang-Mo;Byeon, Do-Yeong;Baek, Seung-Uk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.7
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    • pp.1030-1040
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    • 1998
  • One of the main unresolved issues in large-eddy simulation(LES) of wall-bounded turbulent flows is the requirement of high spatial resolution in the near-wall region, especially in the spanwise direction. Such high resolution required in the near-wall region is generally used throughout the computational domain, making simulations of high Reynolds number, complex-geometry flows prohibitive. A grid-embedding strategy using a nonconforming spectral domain-decomposition method is proposed to address this limitation. This method provides an efficient way of clustering grid points in the near-wall region with spectral accuracy. LES of transitional and turbulent channel flow has been performed to evaluate the proposed grid-embedding technique. The computational domain is divided into three subdomains to resolve the near-wall regions in the spanwise direction. Spectral patching collocation methods are used for the grid-embedding and appropriate conditions are suggested for the interface matching. Results of LES using the grid-embedding strategy are promising compared to LES of global spectral method and direct numerical simulation. Overall, the results show that the spectral domain-decomposition grid-embedding technique provides an efficient method for resolving the near-wall region in LES of complex flows of engineering interest, allowing significant savings in the computational CPU and memory.

Finite element study on the hydro-embedding process (유한요소 해석법을 이용한 하이드로 임베딩 공정연구)

  • Kim D. K.;Park K. S.;Kim D. H.;Moon Y. S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2004.05a
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    • pp.206-209
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    • 2004
  • In the hydroforming process the number of process can be reduced by combining pre-forming process and post-forming process such as the bending, piercing and the embedding process. Integrated studies on the embedding manufacturing technology have been performed by analyzing the deformed mode of the tubes and the optimal process parameters. In this study, a simulation model that can prove clamping force between the clamping element and tube has been investigated by FEM. The characteristics of the embedded parts, such as the shape of the screw tip, screw thread and shape of thread were investigated at various clamping element conditions.

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Effects of Catgut -Embedding Therapy in Patients with Carpal Tunnel Syndrome: a Retrospective Pilot Study

  • You, Kyung-Gon;Kwon, Young-Dal
    • The Journal of Korean Medicine
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    • v.36 no.2
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    • pp.43-49
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    • 2015
  • Objectives: We evaluated the effect of the traditional Korean medical therapy of catgut-embedding therapy in patients with carpal tunnel syndrome (CTS). Methods: Thirteen patients(20 hands) with CTS underwent catgut-embedding therapy once per week for a total of 1-4 sessions. We measured the time to tingling in the fingers on performing Phalen's test. We also had patients use a visual analog scale (VAS) to indicate the severity of tingling. We also asked about the awakening time at night due to pain and tingling. We controlled the treatment as being limited to four sessions. Even if a patient had not been treated for four sessions, we ended the patient's treatment if symptoms resolved. Results: Patients who received catgut-embedding therapy showed significant improvements in the clinical symptoms of CTS. After treatment, in a total of 19 hands, the status of fourteen was changed from positive to negative in Phalen's test and the average of tingling occurrence time in that test was delayed. Among the 20 hands, the VAS in eight hands changed to zero and the average of VAS score decreased. Furthermore, in nine patients, four could sleep well without the use of a splint. Conclusions: Patients undergoing this traditional Korean medical therapy showed alleviation of finger tingling after even a single treatment. We thus concluded that this traditional Korean catgut-embedding therapy, may be effective for treating CTS. However, to confirm the effects of catgut-embedding therapy on CTS, further tests are required, including under the defined, strict conditions of a randomized controlled trial.

An experimental study on the heat transfer characteristics of a Ondol-heated space by varying pipe embedding depths and hot water supply conditions (보일러 운전조건 및 마감층 두께 변화에 따른 온돌난방공간의 열특성에 관한 실험연구)

  • 박병윤
    • Proceeding of Spring/Autumn Annual Conference of KHA
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    • 1991.09a
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    • pp.41-47
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    • 1991
  • This study reports the results of the transient temperature response of a floor heating panel according to variation of the hot water supply temperature and the pipe embedding depth. Also, this experiment compares the temperature responses of floor heating panels under the continuous and intermittent heating system. Furtthermore, this study presents some details of the thermal response of Ondol-heated buildings to varying loads and patterns of heat input. The analysis of the thermal performance fo Ondol heating system have been presented.

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Copyright Protection of Compression Video(MPEG-2) Using Watermark (워터마크를 이용한 동영상미디어(MPEG-2)의 저작권보호)

  • Shin, Jin-Uk;Kim, In-Taek
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.51 no.1
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    • pp.26-31
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    • 2002
  • In this paper, an MPEG-2 based technique for embedding digital watermarks into MPEG-2 video is proposed. The technique hides watermarking information into the DCT coefficients of each frame from MPEG-2 video. Several experiments have been conducted to show the performance in different conditions: the location of embedding watermarks, the change of Bitrates, and relocation of I-pictures in the MPEG video.

A Study on the Uplift Capacity of Plane and Corrugated Pile Foundations for Pipe Frame Greenhouse (파이프 골조온실의 민말뚝 기초와 주름말뚝 기초의 인발저항력에 대한 실험적 연구)

  • 조재홍;윤용철;윤충섭;서원명
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1998.10a
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    • pp.255-261
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    • 1998
  • The recent greenhouses are extremely light-weight structures and easily damaged by the strong winds due to the lack of uplift capacity of pile foundations. The uplift capacity of pile foundations are subject to the shape of the pile surface, diameter, weight, and embedded depths. etc. So, it is very important to figure out the most appropriate conditions on shape of the pile surface and it's embedding depths. to improve wind proof capability of pipe greenhouses. In this study, plane and corrugated pile surfaces were examined on their uplift capacity with 30 to 50 cm of embedding depths. The diameters of tested piles were 10 cm, 15 cm, and 20 cm, respectively. Compaction ratio of the tested soil was 80%. Each test run was repeated three times for the respective treatment. Obtained results are as follows; In all cases, as the diameter and the embedding depth were increased, the ultimate uplift capacity of the pile was also increased. And it was clear that the ultimate uplift capacity of corrugated pile was approximately two times as big as that of plain piles under same conditions.

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A New Approach for Information Security using an Improved Steganography Technique

  • Juneja, Mamta;Sandhu, Parvinder Singh
    • Journal of Information Processing Systems
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    • v.9 no.3
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    • pp.405-424
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    • 2013
  • This research paper proposes a secured, robust approach of information security using steganography. It presents two component based LSB (Least Significant Bit) steganography methods for embedding secret data in the least significant bits of blue components and partial green components of random pixel locations in the edges of images. An adaptive LSB based steganography is proposed for embedding data based on the data available in MSB's (Most Significant Bits) of red, green, and blue components of randomly selected pixels across smooth areas. A hybrid feature detection filter is also proposed that performs better to predict edge areas even in noisy conditions. AES (Advanced Encryption Standard) and random pixel embedding is incorporated to provide two-tier security. The experimental results of the proposed approach are better in terms of PSNR and capacity. The comparison analysis of output results with other existing techniques is giving the proposed approach an edge over others. It has been thoroughly tested for various steganalysis attacks like visual analysis, histogram analysis, chi-square, and RS analysis and could sustain all these attacks very well.