• 제목/요약/키워드: class action

검색결과 305건 처리시간 0.032초

온수 보일러용 열구동 펌프에 관한 연구 (A Study on the Thermal Pump of the Hot Water Boiler)

  • 염한길;김욱중;김창주
    • 연구논문집
    • /
    • 통권30호
    • /
    • pp.15-23
    • /
    • 2000
  • In this study, develop the thermal pump using water evaporation and condensation. Vapor from heating room moves up to pumping room and press the water of pumping room. Consequently water is pumped out to water tank. Then hot vapor direct contact with cold water in condensing room after pumping process. At this time, pressure of condensing room is down to-5kPa and suck in water of tank. This pump executes self ping and good durability because of no mechanical moving parts. Thermal pump is pumped cyclic so that, this pump is not used single. Therefore thermal pump of hot water boiler used to multi-stage for stable pumping rate. As the result of performance test, the developed thermal pump proves pumping action of water evaporation/condensation. And total volume flow rate is 500liter during one hour. If three thermal pump is installed parallel, this pump can use to the hot water boiler in the 300,000kcal/h class.

  • PDF

Developing Geometry Software for Exploration-Geometry Player

  • Yuan, Yuan;Lee, Chun-Yi;Huang, Jiung-Rong
    • 한국수학교육학회지시리즈D:수학교육연구
    • /
    • 제11권3호
    • /
    • pp.209-218
    • /
    • 2007
  • The purpose of this study is to create an interactive tool Geometry Player for geometric explorations. In designing this software, we referred to van Hiele's geometric learning theory of and Duval's cognitive comprehension theory of geometric figures. With Geometry Player, it is easy to construct and manipulate dynamic geometric figures. Teachers can easily present the dynamic process of geometric figures in class, and students can use it as a leaning tool to construct geometric concepts by themselves. It is hoped that Geometry Player can be a useful assistant for teachers and a nice partner for students. A brief introduction to Geometry Player and some application examples are included in this paper.

  • PDF

Lantibiotics, Class I Bacteriocins from the Genus Bacillus

  • Lee, Hyung-Jae;Kim, Hae-Yeong
    • Journal of Microbiology and Biotechnology
    • /
    • 제21권3호
    • /
    • pp.229-235
    • /
    • 2011
  • Antimicrobial peptides exhibit high levels of antimicrobial activity against a broad range of spoilage and pathogenic microorganisms. Compared with bacteriocins produced by lactic acid bacteria, antimicrobial peptides from the genus Bacillus have been relatively less recognized despite their broad antimicrobial spectra. These peptides can be classified into two different groups based on whether they are ribosomally (bacteriocins) or nonribosomally (polymyxins and iturins) synthesized. Because of their broad spectra and high activity, antimicrobial peptides from Bacillus spp. may have great potential for applications in the food, agricultural, and pharmaceutical industries to prevent or control spoilage and pathogenic microorganisms. In this review, we introduce ribosomally synthesized antimicrobial peptides, the lantibiotic bacteriocins produced by members of Bacillus. In addition, the biosynthesis, genetic organization, mode of action, and regulation of subtilin, a well-investigated lantibiotic from Bacillus subtilis, are discussed.

고효율 유도가열형 전기온풍기에 관한 연구 (A Study on the Electrical Fan Heater using High Efficiency Induction Heating)

  • 신대철;우형균
    • 조명전기설비학회논문지
    • /
    • 제26권3호
    • /
    • pp.24-30
    • /
    • 2012
  • A proposed the electrical fan heater using induction heating is innovative system which applied IH(Induction Heating) magnetic induction heating generated from induction-heated metallic package and high-frequency power circuit technique for thermal converse technique. In this occurs not burning, so that the working environment and deterioration of products can be improved. The existing heater that low efficiency by heated resistance or using fossil fuel of coal, diesel, kerosene has problems about burden for high cost price. In this paper are compared efficiency the existing heaters and designed electrical fan heaters using 3[kW]-Class full-bridge resonant inverter. In addition, action analysis and application of system are discussed.

Charge Balance Control Methods for a Class of Fundamental Frequency Modulated Asymmetric Cascaded Multilevel Inverters

  • Babaei, Ebrahim
    • Journal of Power Electronics
    • /
    • 제11권6호
    • /
    • pp.811-818
    • /
    • 2011
  • Modulation strategies for multilevel inverters have typically focused on synthesizing a desired set of sinusoidal voltage waveforms using a fixed number of dc voltage sources. This makes the average power drawn from different dc voltage sources unequal and time varying. Therefore, the dc voltage sources are unregulated and require that corrective control action be incorporated. In this paper, first two new selections are proposed for determining the dc voltage sources values for asymmetric cascaded multilevel inverters. Then two modulation strategies are proposed for the dc power balancing of these types of multilevel inverters. Using the charge balance control methods, the power drawn from all of the dc sources are balanced except for the dc source used in the first H-bridge. The proposed control methods are validated by simulation and experimental results on a single-phase 21-level inverter.

Experimental study on seismic performance of coupling beams not designed for ductility

  • Lam, S.S.E.;Wu, B.;Liu, Z.Q.;Wong, Y.L.
    • Structural Engineering and Mechanics
    • /
    • 제28권3호
    • /
    • pp.317-334
    • /
    • 2008
  • Seismic performance of coupling beams not designed for ductility is examined. Eight 1:4 scale coupling beam specimens, with seven reinforced concrete sections and one composite section, were tested under cycles of push-pull action. Characteristics of the specimens include moderate shear span ratio in the range of 2.5-3.5, high main reinforcement ratio at 3-4% and small to large stirrup spacing with 90- degree hooks. All the reinforced concrete specimens failed in a brittle manner. Displacement ductility of specimens with large stirrup spacing (${\geq}$140 mm) is in the range of 3 to 5. Seismic performance of the specimens is also examined using the ultimate drift angle and the amount of energy dissipated. Correlating the test data, an empirical relationship is proposed to estimate the ultimate drift angle of a class of coupling beams considered in the study not designed for ductility.

컨테이너 크레인의 흔들림 억제 제어에 관한 연구 (A Study on the Sway Suppression Control of Container Cranes)

  • 백운보
    • 한국생산제조학회지
    • /
    • 제21권1호
    • /
    • pp.109-115
    • /
    • 2012
  • In this paper, we consider the sway suppression control problem for container cranes with load hoisting. The proposed control law improves the positioning accuracy but also the sway suppression through fast stabilization of the under-actuated sway dynamics, which is based on a class of feedback linearizing control incorporated with an additional control including the sway angle and its rate as well as positioning errors and their rates. For the design of the additional control, a variable structure control with the proper sway damping and simple switching action is employed, thus preventing excessive overshoots of the trolley travelljng and effectively suppressing the residual sway of container arrived at the target position. Simulation results are provided to show effectiveness of the proposed controller in the presence of such uncertainties as winds and the variation of payload weights.

사상방(四象方) 가감법(加減法) 및 유형(類型)에 대(對)한 가설(假說) (동의수세보원(東醫壽世保元), 사상신편(四象新編)을 중심으로) (A hypothesis on the form and principle of addition-subtraction of the Sasang prescription)

  • 조황성
    • 사상체질의학회지
    • /
    • 제23권2호
    • /
    • pp.139-152
    • /
    • 2011
  • 1. Objectives: This research was proposed to find out the selection and form of addition and subtraction of the Sasang prescription. 2.Methods: The related contents of the pathology and the medical action of a Sasang disease were selected in "Donguisusebowon- Sasangchobongyun, -Gabobon, -Shinchukbon(東醫壽世保元-四象草本卷, -甲午本, -辛丑本)", "Donguisasangsinfyun(東醫四象新編)". 3.Results and Conclusions: 1) The change and development of the Sasang prescription. 2) The selection of drugs are caused by immunity of the ordinary times and a class of present disease. 3) Addition and subtraction of the Sasang prescription can divide 4-type.

퍼지의사결정을 이용한 RC구조물의 건전성평가 (Integrity Assessment for Reinforced Concrete Structures Using Fuzzy Decision Making)

  • 박철수;손용우;이증빈
    • 한국전산구조공학회:학술대회논문집
    • /
    • 한국전산구조공학회 2002년도 봄 학술발표회 논문집
    • /
    • pp.274-283
    • /
    • 2002
  • This paper presents an efficient models for reinforeced concrete structures using CART-ANFIS(classification and regression tree-adaptive neuro fuzzy inference system). a fuzzy decision tree parttitions the input space of a data set into mutually exclusive regions, each of which is assigned a label, a value, or an action to characterize its data points. Fuzzy decision trees used for classification problems are often called fuzzy classification trees, and each terminal node contains a label that indicates the predicted class of a given feature vector. In the same vein, decision trees used for regression problems are often called fuzzy regression trees, and the terminal node labels may be constants or equations that specify the Predicted output value of a given input vector. Note that CART can select relevant inputs and do tree partitioning of the input space, while ANFIS refines the regression and makes it everywhere continuous and smooth. Thus it can be seen that CART and ANFIS are complementary and their combination constitutes a solid approach to fuzzy modeling.

  • PDF

Developments in Hull Strength Monitoring (Developments in Hull Strength Monitoring)

  • P. A. Thomson;Ph. D BMT SeaTech Ltd.
    • 해양환경안전학회지
    • /
    • 제2권1호
    • /
    • pp.143-143
    • /
    • 1996
  • Recent Class requirements and IMO recommendations concerning Hull Strength Monitoring (HSM) have prompted an increasing number of shipowner to adopt monitoring systems on bulk carriers and tanker. Such systems are designed to give warning when stress levels and the frequency and magnitude of ship motions approach levels which require corrective action. When fitted these systems provide enhanced operational safety and efficiency. This paper describes a development beyond the standard BMT HSM system through the integration of stress, motion and radar-based sea state monitoring with powerful, on-board, artificial intelligence (AI) tools. The latter utilises conceptual clustering techniques as an aid to pattern recognition in stress, fatigue. motion and sea state data clusters. This, in turn, provides additional operational guidance for ship's staff. Feedback from applications of the standard BMT HSM and extended HSM systems on board the British Steel Bulk Shipping fleet is described.