• Title/Summary/Keyword: SET*

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Performance Improvement of Triangular-type V-belt Clutch (삼각벨트 클러치의 성능 향상에 관한 연구)

  • 신범수;김상헌;박희찬
    • Journal of Biosystems Engineering
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    • v.24 no.2
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    • pp.99-106
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    • 1999
  • This study was conducted to provide a direction for improving the performance of triangular-type belt clutch. The power transmission characteristics and the wear of belt were investigated for two types of pulley set theoretically and experimentally. The results of research were summarized as follows: 1) Based on the theoretical analysis for the life time of belt, the wear of belt could be reduced by increasing the sizes of driving V-pulley and tension pulley, and by decreasing the tension on V-belt. 2) The pulley set # 2 could transmit more power than the pulley set # 1 could at the same slop rate. While the slip rate was 2.36% on the pulley set # 2 at the maximum power transmission, the slip rate on the pulley set # 1 was increased up to 12.2% at the same condition. 3) From the 16 hours' fatigue test, the wear of belt used n the pulley set # 1 was observed severer than that in the pulley set#2. Also, it was found that the tensile strength of belt used in the pulley set # 2 was greater than that of belt used in the pulley set # 1.

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An Application of the Rough Set Approach to credit Rating

  • Kim, Jae-Kyeong;Cho, Sung-Sik
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 1999.10a
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    • pp.347-354
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    • 1999
  • The credit rating represents an assessment of the relative level of risk associated with the timely payments required by the debt obligation. In this paper, we present a new approach to credit rating of customers based on the rough set theory. The concept of a rough set appeared to be an effective tool for the analysis of customer information systems representing knowledge gained by experience. The customer information system describes a set of customers by a set of multi-valued attributes, called condition attributes. The customers are classified into groups of risk subject to an expert's opinion, called decision attribute. A natural problem of knowledge analysis consists then in discovering relationships, in terms of decision rules, between description of customers by condition attributes and particular decisions. The rough set approach enables one to discover minimal subsets of condition attributes ensuring an acceptable quality of classification of the customers analyzed and to derive decision rules from the customer information system which can be used to support decisions about rating new customers. Using the rough set approach one analyses only facts hidden in data, it does not need any additional information about data and does not correct inconsistencies manifested in data; instead, rules produced are categorized into certain and possible. A real problem of the evaluation of the evaluation of credit rating by a department store is studied using the rough set approach.

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Low Temperature Characteristics of Schottky Barrier Single Electron and Single Hole Transistors

  • Jang, Moongyu;Jun, Myungsim;Zyung, Taehyoung
    • ETRI Journal
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    • v.34 no.6
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    • pp.950-953
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    • 2012
  • Schottky barrier single electron transistors (SB-SETs) and Schottky barrier single hole transistors (SB-SHTs) are fabricated on a 20-nm thin silicon-on-insulator substrate incorporating e-beam lithography and a conventional CMOS process technique. Erbium- and platinum-silicide are used as the source and drain material for the SB-SET and SB-SHT, respectively. The manufactured SB-SET and SB-SHT show typical transistor behavior at room temperature with a high drive current of $550{\mu}A/{\mu}m$ and $-376{\mu}A/{\mu}m$, respectively. At 7 K, these devices show SET and SHT characteristics. For the SB-SHT case, the oscillation period is 0.22 V, and the estimated quantum dot size is 16.8 nm. The transconductance is $0.05{\mu}S$ and $1.2{\mu}S$ for the SB-SET and SB-SHT, respectively. In the SB-SET and SB-SHT, a high transconductance can be easily achieved as the silicided electrode eliminates a parasitic resistance. Moreover, the SB-SET and SB-SHT can be operated as a conventional field-effect transistor (FET) and SET/SHT depending on the bias conditions, which is very promising for SET/FET hybrid applications. This work is the first report on the successful operations of SET/SHT in Schottky barrier devices.

The Computation of the Voronoi Diagram of a Circle Set Using the Voronoi Diagram of a Point Set: I. Topology (점 집합의 보로노이 다이어그램을 이용한 원 집합의 보로노이 다이어그램의 계산: I. 위상학적 측면)

  • ;;;Kokichi Sugihara
    • Korean Journal of Computational Design and Engineering
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    • v.6 no.1
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    • pp.24-30
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    • 2001
  • An efficient and robust algorithm to compute the exact Voronoi diagram of a circle set is presented. The circles are located in a two dimensional Euclidean space, the radii of the circles are non-negative and not necessarily equal, and the circles are allowed to intersect each other. The idea of the algorithm is to use the topology of the point set Voronoi diagram as a seed so that the correct topology of the circle set Voronoi diagram can be obtained through a number of edge flipping operations. Then, the geometries of the Voronoi edges of the circle set Voronoi diagram are computed. In particular, this paper discusses the topological aspect of the algorithm, and the following paper discusses the geometrical aspect. The main advantages of the proposed algorithm are in its robustness, speed, and the simplicity in its concept as well as implementation. Since the algorithm is based on the result of the point set Voronoi diagram and the flipping operation is the only topological operation, the algorithm is always as stable as the Voronoi diagram construction algorithm of a point set.

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Analysis Using Petri Nets for SKP-based SET Protocol (SKP기반 SET프로토콜의 Petri Nets를 이용한 분석)

  • Song, Yu-Jin;Seo, Mi-Gyeong;Lee, Jong-Geun
    • The KIPS Transactions:PartC
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    • v.8C no.5
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    • pp.621-628
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    • 2001
  • SET is one of the useful protocol for credit payment in the Electronic market. Since, the delivery problem is conformed to delivery cooperation not payment problem, the classic SET protocol didn\`t consider about the certification of delivery. But the environment of electronic market be changed to manage the sold, delivery and payment etc.. In this paper, based on this consider, we propose a new SET protocol which has an function to verify the delivery based on SKP and verify it after analyzed by Petri nets. Specially, we consider SKP between Customer, Merchant, and Acquirer for improve the verify function.

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Study on the direct approach to reinitialization in using level set method for simulating incompressible two-phase flows (비압축성 2 상유동의 모사를 위한 level set 방법에서의 reinitialization 직접 접근법에 관한 연구)

  • Cho, Myung-H.;Choi, Hyoung-G.;Yoo, Jung-Y.
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.568-571
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    • 2008
  • The computation of moving interface by the level set method typically requires reinitializations of level set function. An inaccurate estimation of level set function ${\phi}$ results in incorrect free-surface capturing and thus errors such as mass gain/loss. Therefore, accurate and robust reinitialization process is essential to the free-surface flows. In the present paper, we pursue further development of the reinitialization process, which evaluates directly level set function ${\phi}$ using a normal vector in the interface without solving the re-distancing equation of hyperbolic type. The Taylor-Galerkin approximation and P1P1splitting FEM are adopted to discretize advection equation of the level set function and the Navier-Stokes equation, respectively. Advection equation of free surface and re-initialization process are validated with benchmark problems, i.e., a broken dam flow and time-reversed single vortex flow. The simulation results are in good agreement with the existing results.

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A Novel Reversible Data Hiding Scheme for VQ-Compressed Images Using Index Set Construction Strategy

  • Qin, Chuan;Chang, Chin-Chen;Chen, Yen-Chang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.8
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    • pp.2027-2041
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    • 2013
  • In this paper, we propose a novel reversible data hiding scheme in the index tables of the vector quantization (VQ) compressed images based on index set construction strategy. On the sender side, three index sets are constructed, in which the first set and the second set include the indices with greater and less occurrence numbers in the given VQ index table, respectively. The index values in the index table belonging to the second set are added with prefixes from the third set to eliminate the collision with the two derived mapping sets of the first set, and this operation of adding prefixes has data hiding capability additionally. The main data embedding procedure can be achieved easily by mapping the index values in the first set to the corresponding values in the two derived mapping sets. The same three index sets reconstructed on the receiver side ensure the correctness of secret data extraction and the lossless recovery of index table. Experimental results demonstrate the effectiveness of the proposed scheme.

Study on the Solution of Reinitialization Equation for Level Set Method in the Simulation of Incompressible Two-Phase Flows (비압축성 2 상유동의 모사를 위한 Level Set 방법의 Reinitialization 방정식의 해법에 관한 연구)

  • Cho, Myung-Hwan;Choi, Hyoung-Gwon;Yoo, Jung-Yul
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.10
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    • pp.754-760
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    • 2008
  • Computation of moving interface by the level set method typically requires the reinitialization of level set function. An inaccurate estimation of level set function $\phi$ results in incorrect free-surface capturing and thus errors such as mass gain/loss. Therefore, an accurate and robust reinitialization process is essential to the simulation of free-surface flows. In the present paper, we pursue further development of the reinitialization process, which evaluates level set function directly using a normal vector on the interface without solving there-distancing equation of hyperbolic type. The Taylor-Galerkin approximation and P1P1 splitting/SUPG (Streamline Upwind Petrov-Galerkin) FEM are adopted to discretize advection equation of the level set function and the incompressible Navier-Stokes equation, respectively. Advection equation and re-initialization process of free surface capturing are validated with benchmark problems, i.e., a broken dam flow and timereversed single vortex flow. The simulation results are in good agreement with the existing results.

Changes in Total Work, Total Work Ratio, Heart Rate, and Blood Lactate during 75% 1-RM Bench Press Exercise

  • Kim, Ki Hong;Kim, Byung Kwan
    • Medical Lasers
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    • v.10 no.3
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    • pp.153-160
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    • 2021
  • Background and Objectives This study was conducted to investigate the change of total work and total work ratio for each set, peak heart rate during exercise, and blood lactate for each set during the 5-set bench press exercise at 75% one repetition maximum test (1-RM). Materials and Methods Seven men in their 20s with more than 6 months of experience doing resistance exercises were selected as subjects, and their 1-RM bench press was measured two weeks before the experiment and 75% 1-RM was measured one week before the experiment. In this study, total work was measured for each set, and heart rate was measured during rest and set-by-set exercise. Blood lactate was measured during rest time after each set. The raw data were analyzed by repeated one-way ANOVA. Results Total work and total work ratio decreased from 1 set to 4 sets (p < .05), p < .001), heart rate increased from stable at the start of exercise (p < .001) and decreased between 3 sets and 4 sets (p < .05). Blood lactate increased continuously up to 2 sets (p < .001, p < .01). Conclusion In conclusion, total work and heart rate decreased with muscle fatigue during exercise, and blood lactate continuously increased. The results of this study are expected to be useful references for constructing resistance exercise programs in the future.

The Effect of Inclusion versus Exclusion on Consideration Set Size: The Moderating Role of Chronic Indecisiveness

  • Lee, Sarah Heeju;Park, Se-Bum
    • Asia Marketing Journal
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    • v.21 no.1
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    • pp.45-64
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    • 2019
  • A great deal of research has explored individuals' attempts to simplify choices by constructing a consideration set. This research aims to investigate which construction strategy, either inclusion or exclusion, is more likely to be adopted and how the adoption of a particular construction strategy can affect consideration set size while identifying the moderating role of chronic indecisiveness in the construction process. The findings of Study 1 indicate that individuals are more likely to adopt an inclusion strategy to reduce a consideration set to a more manageable size, and that an exclusion strategy results in a larger consideration set. In Study 2, the findings reveal that high-indecisiveness individuals are less likely than low-indecisiveness individuals to select an inclusion strategy, but that high-indecisiveness individuals adopting an inclusion strategy are able to reduce the number of alternatives in a consideration set to a manageable size on par with the size of a consideration set formed by low-indecisiveness individuals without elevating the level of perceived difficulty. The current research contributes to the stream of research on consideration set construction and indecisiveness, and offers useful practical implications for overcoming indecisiveness. Limitations and avenues for further research are also discussed.