• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.2
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• pp.144-153
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• 2008

A numerical analysis has been carried out to examine the flow characteristics and the collection efficiency for fine particles in a cyclone using Computational Fluid Dynamics (CFD) technique. The cyclone with the cylinder diameter of 60 mm has been considered for the investigation of the particle collection in a relatively smaller cyclone with somewhat higher inlet air velocities. Fundamental air flow patterns for different inlet velocities have been calculated and then the motions of particles of different sizes have been obtained. The calculated collection efficiencies for fine particles are compared with the experimental results, which shows a good agreement. The current result can be used for the design of cyclones with high collection efficiency.

• 보존과학연구
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• s.32
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• pp.185-193
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• 2011

The Wallace Collection in London (one of the national museums in the UK) has a gallery dedicated to conservation related displays. As well as permanent displays on the manufacturing techniques and materials of artifacts, there is a specially designed space for temporary conservation exhibitions. Through the example of the current conservation exhibition at the Wallace Collection and similar exhibitions and displays from other museums in the UK, this paper will study how the relationship and communication between the conservation profession and the general public have changed, from conservation as a behind-the-scenes and little-known activity to a closer interaction with the public and as a direct educational tool. The general function of a museum can be seen to have evolved from providing passive information to its visitors to offering more active and various forms of education. Conservation has developed with this change towards more awareness of the profession and its role in the preservation of cultural heritage through public outreach programs and displays.

• Journal of Practical Agriculture & Fisheries Research
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• v.26 no.2
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• pp.14-24
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• 2024

To enhance the usability of smart agriculture, methods for utilizing smart farm data are required. Therefore, this study proposes a scheme for utilizing regional smart farm data by linking it to services. The current status of domestic and foreign smart farm data collection and linkage services is analyzed. To collect and link regional smart farm data, necessary data collection, data cleaning, data storage structure and schema, and data storage and linkage systems are proposed. Based on the standards currently being implemented for regional smart farm internal data storage, a farm schema, environmental information schema, facility control information schema, and growth information schema are designed by extending the crop schema and crop main environmental factor information database schema. A data collection and management system structure based on the Hadoop Ecosystem is designed for data collection and management at regional smart farm data centers. Strategies are proposed for utilizing regional smart farm data to provide smart farm productivity improvement and revenue optimization services, image-based crop analysis services, and virtual reality-based smart farm simulation services.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.97-103
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• 2001

The effects of the electrohydrodynamic (EHD) flow and turbulent diffusion on the collection efficiency of a model ESP composed of the plates with a cavity were studied through numerical computation. The electric field and ion space charge density were calculated by the Poisson equation of the electrical potential and the current continuity equation. The EHD flow field was solved by the continuity and momentum equations of the gas phase including the electrical body force induced by the movement of ions under the electric field. The RNG $k-{\varepsilon}$ model was used to analyze the turbulent flow. The particle concentration distribution was calculated from the convective diffusion equation of the particle phase. As the ion space charge increased, the particulate collection efficiency increased because the electrical potential increased over the entire domain in the ESP. The collection efficiency decreased and then increased, i.e. had a minimum value, as the EHD circulating flow became stronger when the electrical migration velocity of the charged particle was low. However, the collection efficiency decreased with the stronger EHD flow when the electrical migration of the particle was higher relatively. The collection efficiency of the model ESP increased as the turbulent diffusivity of the particle increased when the electrical migration velocity of the particle was low. However, the collection efficiency decreased for increasing the turbulent diffusivity when the electrical migration of the particle was higher relatively.

• Journal of Korean Library and Information Science Society
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• v.48 no.1
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• pp.21-42
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• 2017

This study reports the result of the survey on collection management from 154 school libraries in Korea. The questionnaire is consisted of three section: state of collection, state of book use, and collection management system. Results reveal that (1) elementary schools and middle schools have many books for each student compared to the KLA's School Library Standards; (2) the component ratio of literature books is the biggest in school library collections; (3) the ratio of library book use is overwhelmingly higher in elementary schools than middle schools and high schools; (4) 64.6 percent of library books in the sample are never used during 2013-2015; (5) 74 percent of libraries have its own collection management document; (6) Almost all schools compose its own committee for library management, the committee plays an important roles in the communication among school members, collection development and promotion.

• Journal of the Korean Society for Library and Information Science
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• v.53 no.4
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• pp.189-211
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• 2019

The purpose of this study was to establish the concept of theme collection in the library, to clarify the reality of the theme collection operation. This study was to set up methodology for constructing and operating the theme collection in the future and to provide implications for future development. For this purpose, this study conducted in-depth interviews with a total of 12 directors and librarians from four public libraries. The results of the analysis revealed that the theme collection can be built and function properly with a solid understanding of its collection, users and community, and sharing its services goals and orientations. In addition, it was found that the task of constructing a theme collection contributes to the establishment of the identity of the librarian, and it is interrelated with the various library works. Finally, a comprehensive model of current theme collections was discussed.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3052-3058
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• 2011

A high-speed train is the system that the electric power is supplied through the overhead contact line and drives motors. In this case that the de-wiring beteen the overhead contact line and the pantograph of a high-speed train, the occasion that smooth power supply is not accomplished occurs sometimes. If the de-wiring occurs, the arc discharge may damage the overhead contact line or the pantograph, and the falling-off in power quality may cause the damage and malfunctioning of motor block. This paper presents the methodology that the arc discharge by de-wring between overhead line and pantograph is discriminated through measuring the PT and CT in the vehicle, and measures the current collection characteristics for a high speed train.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.1
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• pp.160-166
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• 2005

In this paper, the combined system equation of motion, which can analyze the dynamic interaction between pantograph and catenary system, is derived by adopting absolute nodal coordinates and rigid body coordinates. The analysis results are compared with real experiment data from test running of Korean high-speed train (HSR 350x). In addition, a computation method for the dynamic stress of contact wire is presented using the derived system equation of motion. This method might be good example and significant in that the structural and multibody dynamics model can be unified into one numerical system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.5
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• pp.854-859
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• 2007

A wind farm consists of many wind generator(WG)s therefore, it is generally a complex power system. A wind farm as a distributed generation(DG) affects utility power system. If a conventional protection schemes are applied, it is difficult to detect faults correctly and the schemes can't provide proper coordination in some cases. This paper presents a protection algorithm for a wind farm which consists of a looped collection circuit. Because the proposed algorithm can distinguish between an internal fault and an external fault in a wind farm, The proposed algorithm can disconnect the faulted section in a wind farm. This algorithm is based on an overcurrent protection technique with the change of the ratio of the output current of a generator to the current of the looped line connected to each generator to collect the each generator's power. In addition, operating time of the algorithm is shortened by using the voltage drop at a generator collection point. The performance of the proposed algorithm was verified under various fault conditions using PSCAD/EMTDC simulations.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.8
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• pp.63-70
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• 2006

This paper presents design of the linear propulsion system of a high-speed (200km/h) dynamic tester for catenary-current collection. Among various propulsion systems, a permanent magnet linear synchronous motor is chosen for need of high acceleration force. The design is performed by the equivalent magnetic circuit method and verified by the finite element method. In addition, analysis of the main effects of various design variables for performance of the propulsion system has been done by using simulation-based DOE method.