• Title/Summary/Keyword: Practical block

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Estimation In-Situ Rockfall Block Weight Distribution Using Scan-Line Survey Results and Examination its applicability in Practical Rockfall Analysis (선조사 결과에 의한 실제낙석무게분포의 추정과 설계적용성 검토)

  • Kim, Su-Chul;Kim, Dong-Hee;Jung, Hyuk-Il;Kim, Seok-Ki
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.10a
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    • pp.639-648
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    • 2005
  • Up to now, practical engineers applying simplicity value of rockfall block weight suggested in design manual without considering in-situ rockfall block weight which reflect joint characteristics. However, the size of rockfall block varies with joint spacing of discontinuities and influences over rockfall analysis results. In this paper, we estimate realistic rockfall block weight distribution using statistical invariances of joint spacing derived from scan-line survey result. And, we study whether this distribution is applicable in practical rockfall analysis directly. As the results of this study, rockfall analysis results that using rockfall block weight distribution estimated from scan-line survey show resonable and realistic outcomes.

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Directed Assembly of Block Copolymers for Defect-Free Nanofabrication (블록공중합체 자기조립제어를 통한 무결함 나노구조제작)

  • Shin, Dong-Ok;Jeong, Seong-Jun;Kim, Bong-Hoon;Lee, Hyung-Min;Park, Seung-Hak;Xia, Guodong;Nghiem, Quoc Dat;Kim, Sang-Ouk
    • Korean Chemical Engineering Research
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    • v.46 no.1
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    • pp.1-6
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    • 2008
  • Block copolymers spontaneously assemble into various nanoscale structures such as spheres, cylinders, and lamellar structures according to the relative volumn ratio of each macromolecular block and their overall molecular weights. The self-assembled structures of block copolymer have been extensively investigated for the applications such as nanocomposites, photonic crystals, nanowires, magnetic-storage media, flash memory devices. However, the naturally formed nanostructures of block copolymers contain a high density of defects such that the practical applications for nanoscale devices have been limited. For the practical application of block copolymer nanostructures, a robust process to direct the assembly of block copolymers in thin film geometry is required to be established. To exploit self-assembly of block copolymer for the nanotechnology, it is indispensible to fabricate defect-free self-assembled nanostructure over an arbitrarily large area.

Epitaxial Self-Assembly of Block Copolymer Thin Film for Nanofabrication

  • Kim, Sang-Ouk
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.293-293
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    • 2006
  • Self-assembled nanostructures of block copolymer thin films have gathered significant attention due to their potential applications as templates for nanofabrication. However the lack of a robust strategy to control the structure formation in thin film geometries has been considered a major obstacle for the practical application. In this presentation 'epitaxial self-assembly' will be introduced as a successful strategy to control the self-assembled nanostructure of block copolymer. Chemically patterned surfaces prepared by advanced lithographic techniques successfully registered nanodomains in block copolymer thin film without any single defect over an arbitrarily large area.

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DEVELOPMENT OF UREA MOLASSES BLOCK AND ITS FIELD APPLICATION IN INDIA (A REVIEW)

  • Kunju, P.J. George
    • Asian-Australasian Journal of Animal Sciences
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    • v.1 no.4
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    • pp.233-239
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    • 1988
  • The base of Indian milk production is the millions of nondescript cows and buffaloes in rural areas, fed mainly on crop residues and agro-industrial wastes. The mainstay of the feeding system is straws and stovers. Therefore the approach to increase the fibrous residues utilisation for animal production was ideal and useful. The methods available for the above purpose were not found acceptable in rural areas owing to certain practical problems. The development of urea molasses block was, therefore aimed at solving the practical field problems. Urea Molasses Block has been developed as a feed supplement that can bring forth an effect of rumen manipulation thereby increase the conversion rate of feeds. The formula and process technology were thus developed. Before starting the mass production and popularisation the product was tested in controlled condition in farms and also in villages. Encouraged with the results the feed is now commercially manufactured under Indian Patent No. 156047.

Study on Analysis Method for Welding Deformation of curved Block - Development of Analysis and Application of real Block (곡 블록 용접변형 해석법에 관한 연구 - 해석법 정립 및 실 블록 적용)

  • Lee Myeong-Su;Jang Gyeong-Bok;Yang Jin-Hyeok;Gang Seong-Su
    • Proceedings of the KWS Conference
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    • 2006.05a
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    • pp.77-79
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    • 2006
  • To achieve high productivity of assembly hull blocks, it is important to predict welding deformations accurately and to apply these data to the production planning. In the deformation analysis of hull block, simplified methods (elastic analysis) such as inherent method, equivalent loading method and local & global approach are usually used instead of thermal-elastic-plastic analysis because of calculating time and cost. To be much more practical, these simplified methods should consider gravity effect of plate and contact condition between the plate and the positioning jig. In this research, using finite element method, practical predicting method for the welding deformation of the curved hull blocks with considering welding sequence, gravity effect and contact condition is proposed.

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A study on the Posture control of a two-wheeled mobile robot (양바퀴 이동로봇의 자세제어에 대한 연구)

  • Joo, Jin-Hwa
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.10 no.6
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    • pp.587-593
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    • 2017
  • In this paper, we propose a method to solve the difficulties in constructing an environment capable of practical training on the theoretical contents of robot control field. We make a two-wheeled mobile robot with Segway structure using LEGO block. In order to demonstrate the validity of using the developed robot as a practical application of advanced control theory of robotics education such as dynamic system and nonlinear system, the robot takes a stable posture while balancing the change of gravity during running. The results of the experiment are shown. By presenting the results, the robots made using the LEGO block are used for practical training of advanced control theory of robotics. It can be used as a tool.

On Practical Issue of Non-Orthogonal Multiple Access for 5G Mobile Communication

  • Chung, Kyuhyuk
    • International Journal of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.67-72
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    • 2020
  • The fifth generation (5G) mobile communication has an impact on the human life over the whole world, nowadays, through the artificial intelligence (AI) and the internet of things (IoT). The low latency of the 5G new radio (NR) access is implemented by the state-of-the art technologies, such as non-orthogonal multiple access (NOMA). This paper investigates a practical issue that in NOMA, for the practical channel models, such as fading channel environments, the successive interference cancellation (SIC) should be performed on the stronger channel users with low power allocation. Only if the SIC is performed on the user with the stronger channel gain, NOMA performs better than orthogonal multiple access (OMA). Otherwise, NOMA performs worse than OMA. Such the superiority requirement can be easily implemented for the channel being static or slow varying, compared to the block interval time. However, most mobile channels experience fading. And symbol by symbol channel estimations and in turn each symbol time, selections of the SIC-performing user look infeasible in the practical environments. Then practically the block of symbols uses the single channel estimation, which is obtained by the training sequence at the head of the block. In this case, not all the symbol times the SIC is performed on the stronger channel user. Sometimes, we do perform the SIC on the weaker channel user; such cases, NOMA performs worse than OMA. Thus, we can say that by what percent NOMA is better than OMA. This paper calculates analytically the percentage by which NOMA performs better than OMA in the practical mobile communication systems. We show analytically that the percentage for NOMA being better than OMA is only the function of the ratio of the stronger channel gain variance to weaker. In result, not always, but almost time, NOMA could perform better than OMA.

A New Approximate DCT Computation Based on Subband Decomposition and Its Application (서브밴드 분리에 근거한 새로운 근사 DCT 계산과 응용)

  • Jeong, Seong-Hwan
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.5
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    • pp.1329-1336
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    • 1996
  • In many image compression applications, the discrete cosine transform (DCY) is well known for is highly efficient coding performance. However, it produces undesirable block artifacts in low-bit rate coding. In addition, in many practical applications, faster computation and easier VLST implementation of DCT coefficients are also important issues. The removal of the block artifacts and faster DCT computation are therefor of practical interest. In this paper, a modified DCTcomputation scheme was investigated, which provides a simple efficient solution to the reduction of the block artifacts while achieving faster computation. We have applied the new ap-proach to the low-bit rate coding and decoding of images. Simulation results on real images have verified the improved performance of the proposed method over the standar d method.

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Development of a Program for Analyzing the Characteristics of the Temperature Distribution of the LPG Engine Cylinder Block (LPG 엔진 실린더 블록의 온도 분포 특성 해석을 위한 프로그램 개발)

  • Son, Byung Jin;You, Chin Sok;Kim, Chang Hun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.22 no.12
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    • pp.1746-1754
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    • 1998
  • A computer program has been developed to predict the heat transfer characteristics and the temperature distribution in the cylinder block of a 4-cylinder, 4-stroke engine. The finete element method is employed to handle the complex geometries associated with the practical cylinder block. The hexahedron finite element is used for a mesh generation of three-dimensional domain. The present numerical procedure has been validated with the measured temperature at several locations of cylinder block. The heat transfer characteristics of engine cylinder block is systematically analyzed for various engine speeds and loading conditions.

A Study on the Determination of the Information Block Length of mBIZ Code (mBIZ 부호의 최적 정보장 결정에 관한 연구)

  • Song, J.C.;Yoo, B.S.;Won, D.H.;Park, B.C.
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.461-464
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    • 1988
  • In order to use mBIZ code as the practical transmission code, the information block length have to be determined. If the information block length is short, timing information disapperance is reduced, but transmission speed is increased as the result of inserted redundancy bit. While, if the information block length is long, timing information disapperance and jitter are caused. So it is very important to determine the optimal timing information block length. Therefore, in this paper, we determined the optimal information block length using S/X endurance method.

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