• Title/Summary/Keyword: block state analysis

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The Tuning of Oscillation Frequency by the Analysis of Characteristics of each Block in Ceramic VCO (세라믹 VCO의 Block 특성 분석을 통한 주파수 튜닝)

  • Yoo Chan-Sei;Lee Woo-Sung
    • Journal of the Microelectronics and Packaging Society
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    • v.11 no.2 s.31
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    • pp.49-52
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    • 2004
  • Ceramic components and modules using LTCC passives are being performed and on the passives included in modules have been studied nowadays. However the characteristics changes of passives in ceramic module due to the coupling between patterns, so each block in module, must be analyzed in the state of module including coupling factors. In our research, characteristics of each block of VCO, resonator part, oscillator part, output part were measured and analyzed to allow the prediction of behavior of VCO.

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Analysis of heat conduction of cylinder block of turbocharged gasoline engine by boundary element method (경계요소법에 의한 터보과급 가솔린기관 실린더블럭의 열전도 해석)

  • 김은태;최영돈;홍진관
    • Journal of the korean Society of Automotive Engineers
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    • v.11 no.2
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    • pp.41-54
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    • 1989
  • In this study, steady state heat conduction problems of the cylinder block of turbocharged gasoline engine were solved by the boundary element method. Surface of the cylinder block was divided by the triangular cells with constant potential. Temperature distribution, effective heat transfer coefficient of the cylinder block were investigated with variation of equivalence ratio, engine speed and boost pressure. The results show that maximum temperature of cylinder block increase rapidly with increasing engine speed and boost pressure. The monolithic structure of cylinder block results in sever inhomogeneity of inner wall temperature at the high engine speed and boost pressure.

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Block Deformation Analysis Using Three-dimensional Discontinuous Deformation Analysis(DDA) (삼차원 불연속 변형 해석(DDA)을 이용한 블록거동해석)

  • 장현익;이정인
    • Tunnel and Underground Space
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    • v.12 no.3
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    • pp.158-170
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    • 2002
  • Since the development of Discontinuous Deformation Analysis (DDA) by Shi (1984), there has been much improvement in the theory and programs. These, however, are all based on the assumption of a two-dimensional plane strain or plane stress state; and because a rock block system is a three-dimensional problem, a two-dimensional analysis has limited application. So a three-dimensional analysis is required in the design of rock slopes and underground spaces where three-dimensional discontinuities dominate stability. In this study three-dimensional DDA program is developed using the Shi's two-dimensional theory and program, and the two cases of three-dimensional block are analysed. The program is applied to one sliding-face blocks and wedge sliding and it gives the good results comparing to the exact solution. Multi-block cases will be analysed for many other application soon.

Performance Analysis of Block Turbo Coded OFDM System Using Channel State Information (채널상태정보를 이용하는 블록터보 부호화된 OFDM 시스템의 성능 분석)

  • Kim, Han-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.2
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    • pp.872-877
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    • 2011
  • In this paper, the new decoding algorithm of Block Turbo Codes using Channel State Information(CSI), which is estimated to compensate for the distorted signal caused by multi-path fading, is proposed in order to improve error correction capacity during decoding procedure in OFDM system. The performance of the new decoding algorithm is compared to that of the conventional decoding algorithm without using channel state information under the Rayleigh fading channel. Experimental results showed that in case of only one iteration coding gains of up to 5.0dB~9.0dB can be obtained by applying the channel state information to the conventional decoding algorithm according to the modulation methods. In addition to that, the new decoding algorithm using channel state information at only one iteration shows a performance improvement of 3.5dB to 5.0dB when compared to the conventional decoding algorithm after four iterations. This leads to reduce the considerable amount of computation.

Dynamic mechanism of rock mass sliding and identification of key blocks in multi-fracture rock mass

  • Jinhai Zhao;Qi Liu;Changbao Jiang;Zhang Shupeng;Zhu Weilong;Ma Hailong
    • Geomechanics and Engineering
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    • v.32 no.4
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    • pp.375-385
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    • 2023
  • There are many joint fissures distributed in the engineering rock mass. In the process of geological history, the underground rock mass undergoes strong geological processes, and undergoes complex geological processes such as fracture breeding, expansion, recementation, and re-expansion. In this paper, the damage-stick-slip process (DSSP), an analysis model used for rock mass failure slip, was established to examine the master control and time-dependent mechanical properties of the new and primary fractures of a multi-fractured rock mass under the action of stress loading. The experimental system for the recemented multi-fractured rock mass was developed to validate the above theory. First, a rock mass failure test was conducted. Then, the failure stress state was kept constant, and the fractured rock mass was grouted and cemented. A secondary loading was applied until the grouted mass reached the intended strength to investigate the bearing capacity of the recemented multi-fractured rock mass, and an acoustic emission (AE) system was used to monitor AE events and the update of damage energy. The results show that the initial fracture angle and direction had a significant effect on the re-failure process of the cement rock mass; Compared with the monitoring results of the acoustic emission (AE) measurements, the master control surface, key blocks and other control factors in the multi-fractured rock mass were obtained; The triangular shaped block in rock mass plays an important role in the stress and displacement change of multi-fracture rock mass and the long fissure and the fractures with close fracture tip are easier to activate, and the position where the longer fractures intersect with the smaller fractures is easier to generate new fractures. The results are of great significance to a multi-block structure, which affects the safety of underground coal mining.

Biomechanical Analysis of Biodegradable Cervical Plates Developed for Anterior Cervical Discectomy and Fusion

  • Cho, Pyung Goo;Ji, Gyu Yeul;Park, Sang Hyuk;Shin, Dong Ah
    • Asian Spine Journal
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    • v.12 no.6
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    • pp.1092-1099
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    • 2018
  • Study Design: In-vitro biomechanical investigation. Purpose: To evaluate the biomechanical effects of the degeneration of the biodegradable cervical plates developed for anterior cervical discectomy and fusion (ACDF) on fusion and adjacent levels. Overview of Literature: Biodegradable implants have been recently introduced for cervical spine surgery. However, their effectiveness and safety remains unclear. Methods: A linear three-dimensional finite element (FE) model of the lower cervical spine, comprising the C4-C6 vertebrae was developed using computed tomography images of a 46-year-old woman. The model was validated by comparison with previous reports. Four models of ACDF were analyzed and compared: (1) a titanium plate and bone block (Tita), (2) strong biodegradable plate and bone block (PLA-4G) that represents the early state of the biodegradable plate with full strength, (3) weak biodegradable plate and bone block (PLA-1G) that represents the late state of the biodegradable plate with decreased strength, and (4) stand-alone bone block (Bloc). FE analysis was performed to investigate the relative motion and intervertebral disc stress at the surgical (C5-C6 segment) and adjacent (C4-C5 segment) levels. Results: The Tita and PLA-4G models were superior to the other models in terms of higher segment stiffness, smaller relative motion, and lower bone stress at the surgical level. However, the maximal von Mises stress at the intervertebral disc at the adjacent level was significantly higher in the Tita and PLA-4G models than in the other models. The relative motion at the adjacent level was significantly lower in the PLA-1G and Bloc models than in the other models. Conclusions: The use of biodegradable plates will enhance spinal fusion in the initial stronger period and prevent adjacent segment degeneration in the later, weaker period.

Evaluating the effects of the inclinations of rock blocks on the stability of bimrock slopes

  • Khorasani, Emad;Amini, Mehdi;Hossaini, Mohammad Farouq;Medley, Edmund
    • Geomechanics and Engineering
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    • v.17 no.3
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    • pp.279-285
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    • 2019
  • The process of slope stability analysis is one of the most important stages in design of some civil and mining projects. Bimslopes are made from bimrocks (block-in-matrix rocks) where rocky blocks are distributed in a bonded matrix of finer texture. These kind of slopes are often seen in weathered and near-surface depths. Previous studies have shown that VBP (Volumetric Block Proportion) is one of the most significant factors affecting bimrocks strength and consequently the stability of bimslopes. In this paper, the influence of block inclinations on bimslope stability have been investigated. For this purpose, 180 theoretical models have been made with various VBPs, all of them have a specified block size distribution. These bimslopes contain blocks with differing dips relative the slope inclination. Also for each kind of block inclination, 10 different blocks arrangements have been modeled. The Finite Element Method (FEM) was used to analysis the stability of these bimslopes models. The results showed the inclination of blocks has a strong impact on the Safety Factor and stability of bimslopes. When the difference in angle of dip of blocks relative to the slope angle is maximum, the Safety Factor of bimslopes tends to be a maximum compared with the matrix-only state. Furthermore, with increasing VBP of bimslopes stability increases. The graphs obtained from this study could be used for preliminary guidance in the projects design with bimslopes.

The Method for Extracting Meaningful Patterns Over the Time of Multi Blocks Stream Data (시간의 흐름과 위치 변화에 따른 멀티 블록 스트림 데이터의 의미 있는 패턴 추출 방법)

  • Cho, Kyeong-Rae;Kim, Ki-Young
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.10
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    • pp.377-382
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    • 2014
  • Analysis techniques of the data over time from the mobile environment and IoT, is mainly used for extracting patterns from the collected data, to find meaningful information. However, analytical methods existing, is based to be analyzed in a state where the data collection is complete, to reflect changes in time series data associated with the passage of time is difficult. In this paper, we introduce a method for analyzing multi-block streaming data(AM-MBSD: Analysis Method for Multi-Block Stream Data) for the analysis of the data stream with multiple properties, such as variability of pattern and large capacitive and continuity of data. The multi-block streaming data, define a plurality of blocks of data to be continuously generated, each block, by using the analysis method of the proposed method of analysis to extract meaningful patterns. The patterns that are extracted, generation time, frequency, were collected and consideration of such errors. Through analysis experiments using time series data.

Study on the Thermal Stress Distribution Characteristivs of the Cylinder Block of a Light Gasoline Engine (경차용 가솔린 기관 실린더 블럭의 열응력 분포 특성에 대한 연구)

  • 김병탁
    • Journal of Advanced Marine Engineering and Technology
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    • v.22 no.6
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    • pp.800-808
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    • 1998
  • In this study the thermal stress distribution and deformantion characteristics resulting from the nonuniform temperature fields of the cylinder block of a light 3-cylinder 4-stroke gasoline engine were analyzed using the 3-dimensional finite element method. The temperature distributions req-uisite for the thermoelastic behavior alalysis were obtained from the steady-state heat conduction analysis performed on the basis of experimental data. in order to examine the effect of a ceramic material the cylinder liner was replaced by the silicon nitride($Si_{3}N_{4}$) and its thermal behaviors were compared with those of the original block.

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