• Title/Summary/Keyword: Multiple Columns

Search Result 87, Processing Time 0.029 seconds

Transaction Processing Method for NoSQL Based Column

  • Kim, Jeong-Joon
    • Journal of Information Processing Systems
    • /
    • v.13 no.6
    • /
    • pp.1575-1584
    • /
    • 2017
  • As interest in big data has increased recently, NoSQL, a solution for storing and processing big data, is getting attention. NoSQL supports high speed, high availability, and high scalability, but is limited in areas where data integrity is important because it does not support multiple row transactions. To overcome these drawbacks, many studies are underway to support multiple row transactions in NoSQL. However, existing studies have a disadvantage that the number of transactions that can be processed per unit of time is low and performance is degraded. Therefore, in this paper, we design and implement a multi-row transaction system for data integrity in big data environment based on HBase, a column-based NoSQL which is widely used recently. The multi-row transaction system efficiently performs multi-row transactions by adding columns to manage transaction information for every user table. In addition, it controls the execution, collision, and recovery of multiple row transactions through the transaction manager, and it communicates with HBase through the communication manager so that it can exchange information necessary for multiple row transactions. Finally, we performed a comparative performance evaluation with HAcid and Haeinsa, and verified the superiority of the multirow transaction system developed in this paper.

A Study on the Design of Multiple Object Movements Using Few Power Units and Machanisms (소수의 동력장치와 메커니즘을 이용한 다수의 객체움직임 디자인에 관한 연구)

  • Kang, Hee-Ra
    • Journal of Digital Convergence
    • /
    • v.18 no.12
    • /
    • pp.543-548
    • /
    • 2020
  • The purpose of this study is to implement various movements of multiple objects using a small number of power devices in producing a kinetic design, achieving an effect similar to a work comprised of multiple objects controlled using multiple power devices. While it is more typical to control various objects using multiple power devices, the use of multiple devices leads to higher costs and heavier overall weight. In addition, more power is required to operate the multiple power devices. This study applied a mechanism that allows multiple objects to perform various movements using a small number of power devices. The mechanism significantly reduces overall weight and power consumption. In addition, various movements could be expressed by increasing the rows and columns of objects through the use of the camshaft structure that changed the position and shape of the cam and the use of bevel gears. The significance of this study lies in presenting a new method of controlling multiple objects for designers involved in kinetic design.

Construction of Multiple-Rate Quasi-Cyclic LDPC Codes via the Hyperplane Decomposing

  • Jiang, Xueqin;Yan, Yier;Lee, Moon-Ho
    • Journal of Communications and Networks
    • /
    • v.13 no.3
    • /
    • pp.205-210
    • /
    • 2011
  • This paper presents an approach to the construction of multiple-rate quasi-cyclic low-density parity-check (LDPC) codes. Parity-check matrices of the proposed codes consist of $q{\times}q$ square submatrices. The block rows and block columns of the parity-check matrix correspond to the hyperplanes (${\mu}$-fiats) and points in Euclidean geometries, respectively. By decomposing the ${\mu}$-fiats, we obtain LDPC codes of different code rates and a constant code length. The code performance is investigated in term of the bit error rate and compared with those of LDPC codes given in IEEE standards. Simulation results show that our codes perform very well and have low error floors over the additive white Gaussian noise channel.

Influence of Heat-Treatment on the Adhesive Strength between a Micro-Sized Bonded Component and a Silicon Substrate under Bend and Shear Loading Conditions

  • Ishiyama, Chiemi
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.32 no.2
    • /
    • pp.122-130
    • /
    • 2012
  • Adhesive bend and shear tests of micro-sized bonded component have been performed to clarify the relationship between effects of heat-treatment on the adhesive strength and the bonded specimen shape using Weibull analysis. Multiple micro-sized SU-8 columns with four different diameters were fabricated on a Si substrate under the same fabrication condition. Heat-treatment can improve both of the adhesive bend and shear strength. The improvement rate of the adhesive shear strength is much larger than that of the adhesive bend strength, because the residual stress, which must change by heat-treatment, should effect more strongly on the shear loading. In case of bend type test, the adhesive bend strength in the smaller diameters (50 and $75\;{\mu}m$) widely vary, because the critical size of the natural defect (micro-crack) should vary more widely in the smaller diameters. In contrast, in case of shear type test, the adhesive shear strengths in each diameter of the columns little vary. This suggests that the size of the natural defects may not strongly influence on the adhesive shear strength. All the result suggests that both of the adhesive bend and shear strengths should be complicatedly affected by heat-treatment and the bonded columnar diameter.

Cap truss and steel strut to resist progressive collapse in RC frame structures

  • Zahrai, Seyed Mehdi;Ezoddin, Alireza
    • Steel and Composite Structures
    • /
    • v.26 no.5
    • /
    • pp.635-647
    • /
    • 2018
  • In order to improve the efficiency of the Reinforced Concrete, RC, structures against progressive collapse, this paper proposes a procedure using alternate path and specific local resistance method to resist progressive collapse in intermediate RC frame structures. Cap truss consists of multiple trusses above a suddenly removed structural element to restrain excessive collapse and provide an alternate path. Steel strut is used as a brace to resist compressive axial forces. It is similar to knee braces in the geometry, responsible for enhancing ductility and preventing shear force localization around the column. In this paper, column removals in the critical position at the first story of two 5 and 10-story regular buildings strengthened using steel strut or cap truss are studied. Based on nonlinear dynamic analysis results, steel strut can only decrease vertical displacement due to sudden removal of the column at the first story about 23%. Cap truss can reduce the average vertical displacement and column axial force transferred to adjacent columns for the studied buildings about 56% and 61%, respectively due to sudden removal of the column. In other words, using cap truss, the axial force in the removed column transfers through an alternate path to adjacent columns to prevent local or general failure or to delay the progressive collapse occurrence.

An Analytical Evaluation of 2D Mesh-connected SIMD Architecture for Parallel Matrix Multiplication (2D Mesh SIMD 구조에서의 병렬 행렬 곱셈의 수치적 성능 분석)

  • Kim, Cheong-Ghil
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
    • /
    • v.10 no.1
    • /
    • pp.7-13
    • /
    • 2011
  • Matrix multiplication is a fundamental operation of linear algebra and arises in many areas of science and engineering. This paper introduces an efficient parallel matrix multiplication scheme on N ${\times}$ N mesh-connected SIMD array processor, called multiple hierarchical SIMD architecture (HMSA). The architectural characteristic of HMSA is the hierarchically structured control units which consist of a global control unit, N local control units configured diagonally, and $N^2$ processing elements (PEs) arranged in an N ${\times}$ N array. PEs are communicating through local buses connecting four adjacent neighbor PEs in mesh-torus networks and global buses running across the rows and columns called horizontal buses and vertical buses, respectively. This architecture enables HMSA to have the features of diagonally indexed concurrent broadcast and the accessibility to either rows (row control mode) or columns (column control mode) of 2D array PEs alternately. An algorithmic mapping method is used for performance evaluation by mapping matrix multiplication on the proposed architecture. The asymptotic time complexities of them are evaluated and the result shows that paralle matrix multiplication on HMSA can provide significant performance improvement.

  • PDF

A basic study of steel-joint connection method of composite precast concrete members (합성 PC부재의 Steel-joint Connection Method 개발 기초연구)

  • Kim, Geun-Ho;Lee, Dong-Hoon;Kim, Sun-Kuk
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2013.05a
    • /
    • pp.10-11
    • /
    • 2013
  • Green Frame is a column-beam system formed by composite precast concrete column and beam connected with steel buried in both members. During the installation of Green columns, the columns of Green Frame, covering 3 floors per each piece and beams, the eccentricity can be observed due to the construction error and the weight of beam itself. Such eccentricity may have a little influence on a single frame, yet, it can develop critical issues to the installation of subsequent beams or beams on the upper floors in the context of a building as a whole that has multiple frames. These issues lead to delay in frame installation, decrease of productivity and increase of cost, etc. Therefore, this study presents a steel-joint connection method in order to solve the issues. The steel-joint connection method exists on slope plane and reinforcing plate in steel frame buried in composite PC members. Through this method, the issues can be resolved without requiring additional equipment or manpower.

  • PDF

Analysis of Heterocyclic Amines in Human Urine Using Multiple Solid-Phase Extraction by Liquid Chromatography/Mass Spectrometry

  • Cha, Hyun-Jeong;Kim, Nam-Hee;Jeong, Eun-Kyung;Na, Yun-Cheol
    • Bulletin of the Korean Chemical Society
    • /
    • v.31 no.8
    • /
    • pp.2322-2328
    • /
    • 2010
  • A multiple solid-phase extraction (SPE) method was used with liquid chromatography, coupled with mass spectrometry (LC/MS), for the analysis of heterocyclic amines (HCAs) in human urine. Separation efficiencies based on the pH of the mobile phase and the types of columns were compared. An amide column showed better baseline separation and narrower HCA peak widths at pH 5.0 for the mobile phase than a $C_8$ column. Each SPE step, HLB, MCX, and HybridSPE, was optimized by controlling the pH conditions. The combined method with the three SPEs effectively removed interfering species that cause ion-suppression during HCA detection. Validation of the method, performed with SIM and SRM detection, showed correlation coefficients above 0.991 in the range 0.3 - 16.7 ng/mL. Recovery rates were 45.4 - 97.3% on the $C_8$ column and 71.8 - 101.4% on the amide column, and method detection limits were 0.11 - 0.65 ng/mL on the $C_8$ column and 0.12 - 0.48 ng/mL on the amide column. This method using multiple SPEs offers significant benefits for high-throughput determination of HCAs in urine.

Test of Headed Reinforcement in Pullout

  • Park, Dong-Uk;Hong, Sung-Gul;Lee, Chin-Yong
    • KCI Concrete Journal
    • /
    • v.14 no.3
    • /
    • pp.102-110
    • /
    • 2002
  • Results of an experimental study on the pullout behavior of the headed reinforcement are presented. A total of 48 pullout tests was performed to evaluate pullout strengths and load-displacement behaviors in pullout of the headed bars. The square steel heads had gross area of 4 $A_{b}$ and thickness of $d_{b}$ The test program consisted of three pullout test groups: Simple and Edge pullout tests using plain concrete slabs, comparison of pullout performances between the standard hooks and the headed reinforcement, and pullout tests of headed reinforcement using reinforced concrete columns. Test variables included concrete strengths ( $f_{c}$' = 27.1MPa, 39.1MPa), reinforcing bar diameters (D16~D29), embedment depths (6 $d_{b}$~12 $d_{b}$), edge conditions, column reinforcement, and single-vs.-multiple bar pullout. Test results revealed that the heads effectively provided the pullout resistances of the deformed bars in tension. The load-displacement behaviors were similar between the 90-degree hooks and the headed reinforcement. When a multiple number of headed bars installed with small head-to-head spacings was pulled out, reinforcement designed to run across the concrete failure surface in a direction parallel to the headed bars helped improve the pullout performances of the headed reinforcement.t.ement.t.

  • PDF

Wafer level vertical interconnection method for microcolumn array (마이크로컬럼 어레이에 적용 가능한 웨이퍼단위의 수직 배선 방법)

  • Han, Chang-Ho;Kim, Hyeon-Cheol;Kang, Moon-Koo;Chun, Kuk-Jin
    • Proceedings of the IEEK Conference
    • /
    • 2005.11a
    • /
    • pp.793-796
    • /
    • 2005
  • In this paper, we propose a method which can improve uniformity of a miniaturized electron beam array for inspection of very small pattern with high speed using vertical interconnection. This method enables the individual control of columns so that it can reduce the deviation of beam current, beam size, scan range and so on. The test device that used vertical interconnection method was fabricated by multiple wafer bonding and metal reflow. Two silicon and one glass wafers were bonded and metal interconnection by melting of electroplated AuSn was performed. The contact resistance was under $10{\Omega}$.

  • PDF