• Title/Summary/Keyword: Experimental designs

Search Result 742, Processing Time 0.028 seconds

Flow Characteristics of a Primary Cooling System in 5 MW Research Reactor (5MW 연구용 원자로의 1차 냉각 계통 유동 특성)

  • Park, Young-Chul;Lee, Young-Sub
    • The KSFM Journal of Fluid Machinery
    • /
    • v.13 no.5
    • /
    • pp.5-10
    • /
    • 2010
  • 5MW, open pool type research reactor, is commonly used to education and experimental purpose. It is necessary to prepare a standardization of system designs for considering a demand. HANARO has prepared the standardization of 5MW research reactor system designs based on the design, installation, commissioning and operating experiences of HANARO. For maintaining an open pool type reactor safety, a primary cooling system (after below, PCS) should remove the heat generated by the reactor under a reactor normal operation condition and a reactor shutdown condition. For removing the heat generated by the reactor, the PCS should maintain a required coolant flow rate. For a verification of the required flow rate, a flow network analysis of the PCS was carried under a normal operating condition. Based on the flow network analysis result, this paper describes the PCS flow characteristics of a 5MW open pool type research reactor. Through the result, it was confirmed that the PCS met design requirements including design flow rate without cavitation.

Comparison of Efficiency between Two Auction Designs for CO2 Emission Allowances : Uniform Pricing vs. Multiple Pricing (탄소배출권 경매할당의 방법론에 대한 효율성 비교: 단일가격 결정방식 vs. 복수가격 결정방식)

  • Kim, Hyo-Sun;Yoo, Sang Hee
    • Environmental and Resource Economics Review
    • /
    • v.19 no.1
    • /
    • pp.23-43
    • /
    • 2010
  • This article compares two different auction designs for $CO_2$ emission allowances, namely uniform pricing and multiple pricing, in view of market efficiency. Experimental economic method of Buckley et al. (2004) is applied in this analysis. As a result of this analysis as expected, multiple pricing method brings out Winner's curse. It means that uniform pricing method is more efficient than multiple pricing method.

  • PDF

Experimental Study on Characteristics of Granular Materials Containing Recycled Aggregates (순환골재를 포함한 입상재료의 특성에 관한 실험적 연구)

  • Hong, Seok-Woo;Gwon, Gi-Cheol;Han, Yeong-Seong
    • International Journal of Highway Engineering
    • /
    • v.15 no.2
    • /
    • pp.83-94
    • /
    • 2013
  • PURPOSES : In Korea, most designs of pavement had been mainly performed by considering CBR of granular materials before KPRP(Korea Pavement Research Program) and 86 AASHTO design method were introduced. Since then, the trend of the pavement designs gradually have moved to using mechanical characteristics throughout the resilient modulus based on the test results up to recently. In this study, we should like to research the mechanical characteristics of paving materials containing Recycled aggregates through the cyclic loading triaxial compression tests. METHODS : The kinds of materials were tested; coarse grained subbase materials, refining aggregates base materials and recycled aggregates. RESULTS : The present study aims to figure out the resilient modulus of paving materials containing Recycled aggregates through the cyclic loading triaxial compression tests. CONCLUSIONS : The test results revealed that the engineering properties of the recycled aggregates were more excellent than the those of others.

SAMPLING ERROR ANALYSIS FOR SOIL MOISTURE ESTIMATION

  • Kim, Gwang-Seob;Yoo, Chul-sang
    • Water Engineering Research
    • /
    • v.1 no.3
    • /
    • pp.209-222
    • /
    • 2000
  • A spectral formalism was applied to quantify the sampling errors due to spatial and/or temporal gaps in soil moisture measurements. The lack of temporal measurements of the two-dimensional soil moisture field makes it difficult to compute the spectra directly from observed records. Therefore, the space-time soil moisture spectra derived by stochastic models of rainfall and soil moisture was used in their record. Parameters for both models were tuned with Southern Great Plains Hydrology Experiment(SGP'97) data and the Oklahoma Mesonet data. The structure of soil moisture data is discrete in space and time. A design filter was developed to compute the sampling errors for discrete measurements in space and time. This filter has the advantage in its general form applicable for all kinds of sampling designs. Sampling errors of the soil moisture estimation during the SGP'97 Hydrology Experiment period were estimated. The sampling errors for various sampling designs such as satedlite over pass and point measurement ground probe were estimated under the climate condition between June and August 1997 and soil properties of the SGP'97 experimental area. The ground truth design was evaluated to 25km and 50km spatial gap and the temporal gap from zero to 5 days.

  • PDF

FRACTURE BEHAVIOR OF CONDENSABLE COMPOSITE RESINS (응축형 복합레진의 파괴거동에 관한 연구)

  • Kim, So-Young;Choi, Ho-Young;Choi, Kyoung-Kyu;Park, Sang-Jin
    • Restorative Dentistry and Endodontics
    • /
    • v.25 no.3
    • /
    • pp.446-458
    • /
    • 2000
  • In this study, compressive strengths of three condensable composite resins(ALERT, SureFil, Solitaire), conventional hybrid composite resin(Z-100) and amalgam(HI-Aristaloy 21) according to the 6 types of cavity design(cylinder, trapezoidal, butt-joint, round bevel, long bevel and short bevel) were measured and appearance of fracture surfaces were observed with SEM, thus evaluated clinical applications of condensable composite resins according to the cavity designs. The results were as follows; 1. Compressive strengths according to experimental materials were the highest in SureFil, and Z-100, ALERT, Solitaire, HI-Aristaloy 21 in order. 2. SureFil showed the highest compressive strength(p<0.05). compressive strengths of ALERT and Solitaire were lower than that of Z-100, hybrid composite(p<0.05). 3. Compressive strengths according to specimen design were the highest in trapezoidal shape(p<0.05) and no significant difference was detected between other specimen designs. 4. The appearance of condensable composite resin under SEM was of a diverse configuration according to component of resin matrix, shapes of filler and surface treatments between resin and filler.

  • PDF

A Study on the Expressional Characteristic of Glass outer Skin in Contemporary Space Design - Focusing on the case after 2000 - (현대 공간디자인에 있어서 유리외피의 표현특성에 관한 연구 - 2000년 이후의 사례를 중심으로 -)

  • Kim, Eun-Jung;Hong, Kwan-Seon
    • Korean Institute of Interior Design Journal
    • /
    • v.17 no.3
    • /
    • pp.123-130
    • /
    • 2008
  • This study is about the Characteristic of glass outer skin expressions in space designs of contemporary society, due to the rapid development of information and digital technology. These days, the glass outer skin show the various images and space expressions which symbolize the informations and the society. The contemporary space designers focus on the glass as the structure materials, and purposely use the glass to achieve the structure concept which satisfies the needs of contemporary society. Therefore, it is a valuable work to analyze the meaning of glass, which has been used for the structure. Throughout the work which has been experienced by glass outer skin, theoretical studies have been achieved and recently the 14 examples were chosen as the glass structures based on the experimental research and frequency featured in magazines after year 2000, which we have analyzed in detail. Glass outer skin reflect the phrases of time in modern society, and throughout the meaning of it, we could see that the glass outer skin serve the roles in informations, interface, imaginary modernization, and as a landmark position. Therefore, in this study, we can make a definition of glass outer skin expression based on the situations of modem times by analyzing the symbolic meaning of glass outer skin in contemporary space designs.

An hygienical study on fomentation wear textile and design

  • Shim, Boo-Ja
    • Journal of Fashion Business
    • /
    • v.9 no.6
    • /
    • pp.101-116
    • /
    • 2005
  • The study with the subjects of the female consumers of the fomentation rooms in their 20s, this research made an investigation of the fomentation wear. Also, dye-fastness experiments of the wear's colors against washing and sweating were held. The following are the conclusions; 1. Survey Results of the Present Situations of Fomentation Wear Designs of the fomentation wear, 88% belonged to a T-shirt (upper clothes) and knee pants. The primary colors of the wear were in the order of gray (37.5%), white (31.3%), orange (25%), indigo (18.8%), and yellowish (18.8%). 43% of the wear companies used the same color for two-piece clothes, and 57% employed different colors for upper and lower clothes. 2. Consumers' Attitude about Fomentation Wear The key problem in the attitude to the wear, 25.9% pointed out the worries about physical exposure (like breasts and legs) owing to the improperness in designs and sizes. 32.8% of the subjects were also worried about physical silhouette exposure following sweating. The need for design improvement was felt as the subjects expressed their intention to use better fomentation wear in design and materials if the fare is higher. 3. Experimental Results of the Dye fastness of the Fomentation Wear Dye-fastness experiments by sweating appeared in the order of gray > white > pink. The results by washing were gray & white > pink. As laundry grew in number, the grade of dye fastness fell a little bit. In the fomentation environment with more laundry and more perspiration, dye fastness of the wear's colors against washing and sweating should be fully considered.

Design of digital nuclear power small reactor once-through steam generator control system

  • Qian, Hong;Zou, Mingyao
    • Nuclear Engineering and Technology
    • /
    • v.54 no.7
    • /
    • pp.2435-2443
    • /
    • 2022
  • The once-through steam generator used in the small modular reactor needs to consider the stability of the outlet steam pressure and steam superheat of the secondary circuit to achieve better operating efficiency. For this reason, this paper designs a controllable operation scheme for the steam pressure and superheat of the small reactor once-through steam generator. On this basis, designs a variable universe fuzzy controller, first, design the fuzzy control rules to make the controller adjust the PI controller parameters according to the change of the error; secondly, use the domain adjustment factor to further subdivide the input and output domain of the fuzzy controller according to the change of the error, to improve the system control performance. The simulation results show that the operation scheme proposed in this paper have better system performance than the original scheme of the small reactor system, and controller proposed in this paper have better control performance than traditional PI controller and fuzzy PI controller, what's more, the designed control system also showed better anti-disturbance performance in lifting experiment between 100% and 80% working conditions. Finally, the experimental platform formed by connecting the digital small reactor with Matlab/Simulink through OPC(OLE for Process Control) communication technology also verified the feasibility of the proposed scheme.

Study of Personal Credit Risk Assessment Based on SVM

  • LI, Xin;XIA, Han
    • The Journal of Industrial Distribution & Business
    • /
    • v.13 no.10
    • /
    • pp.1-8
    • /
    • 2022
  • Purpose: Support vector machines (SVMs) ensemble has been proposed to improve classification performance of Credit risk recently. However, currently used fusion strategies do not evaluate the importance degree of the output of individual component SVM classifier when combining the component predictions to the final decision. To deal with this problem, this paper designs a support vector machines (SVMs) ensemble method based on fuzzy integral, which aggregates the outputs of separate component SVMs with importance of each component SVM. Research design, data, and methodology: This paper designs a personal credit risk evaluation index system including 16 indicators and discusses a support vector machines (SVMs) ensemble method based on fuzzy integral for designing a credit risk assessment system to discriminate good creditors from bad ones. This paper randomly selects 1500 sample data of personal loan customers of a commercial bank in China 2015-2020 for simulation experiments. Results: By comparing the experimental result SVMs ensemble with the single SVM, the neural network ensemble, the proposed method outperforms the single SVM, and neural network ensemble in terms of classification accuracy. Conclusions: The results show that the method proposed in this paper has higher classification accuracy than other classification methods, which confirms the feasibility and effectiveness of this method.

Evaluating direct vessel injection accident-event progression of AP1000 and key figures of merit to support the design and development of water-cooled small modular reactors

  • Hossam H. Abdellatif;Palash K. Bhowmik;David Arcilesi;Piyush Sabharwall
    • Nuclear Engineering and Technology
    • /
    • v.56 no.6
    • /
    • pp.2375-2387
    • /
    • 2024
  • The passive safety systems (PSSs) within water-cooled reactors are meticulously engineered to function autonomously, requiring no external power source or manual intervention. They depend exclusively on inherent natural forces and the fundamental principles of reactor physics, such as gravity, natural convection, and phase changes, to manage, alleviate, and avert the release of radioactive materials into the environment during accident scenarios like a loss-of-coolant accident (LOCA). PSSs are already integrated into such operating commercial reactors as the Advanced Pressurized Reactor-1000 MWe (AP1000) and the Water-Water Energetic Reactor-1200 MWe (WWER-1200) are adopted in most of the upcoming small modular reactor (SMR) designs. Examples of water-cooled SMR PSSs are the passive emergency core-cooling system (ECCS), passive containment cooling system (PCCS), and passive decay-heat removal system, the designs of which vary based on reactor system-design requirements. However, understanding the accident-event progression and phases of a LOCA is pivotal for adopting a specific PSS for a new SMR design. This study covers the accident-event progression for direct vessel injection (DVI) small-break loss-of-coolant accident (SB-LOCA), associated physics phenomena, knowledge gaps, and important figures of merit (FOMs) that may need to be evaluated and assessed to validate thermal-hydraulics models with an available experimental dataset to support new SMR design and development.