• Title/Summary/Keyword: Base practice

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The Wireless Network Optimization of Power Amplification via User Volume in the Microcell Terrain

  • Guo, Shengnan;Jiang, Xueqin;Zhang, Kesheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.6
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    • pp.2581-2594
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    • 2018
  • The microcell terrain is the most common wireless network terrain in our life. In order to solve wireless network optimization of weak coverage in the microcell terrain, improve call quality and reduce the cost of the premise, power amplifiers in base stations should be adjusted according to user volume. In this paper, characteristics of microcell topography are obtained after analysis. According to the topography characteristics of different microcells, changes in the number of users at different times have been estimated, meanwhile, the number of scatter users are also obtained by monitoring the PCCPCH RSCP and other parameters. Then B-Spline interpolation method has been applied to scatter users to obtain the continuous relationship between the number of users and time. On this basis, power amplification can be chosen according to changes in the number of users. The methods adopted by this paper are also applied in the engineering practice, sampling and interpolation are used to obtain the number of users at all times, so that the power amplification can be adjusted by the number of users in a microcell. Such a method is able to optimize wireless network and achieve a goal of expanding the area of base stations, reduce call drop rate and increase capacity.

A Comparative Studies on the Korean Brick Pagoda (한국전탑(韓國塼塔)에 관한 비교론적(比較論的) 연구(硏究))

  • Cheon, Deuk-Youm;Kim, Eun-Yang
    • Journal of architectural history
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    • v.4 no.2 s.8
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    • pp.25-44
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    • 1995
  • Bricks are the earliest man-made building materials. Small-size bar bricks were found in use in the Warring States Period(戰國時代) in China. During the Qin(秦) and the Han(漢) Dynasties, brick constructions were built on a larger scale, but most of them were tombs. In case of Korea, bricks were found in use in the Three Kingdoms Period, but also most of them were tombs. Starting from the Unified Silla Period(統一新羅時代), brick gradually became a universal practice to built Buddhist Pagodas with bar bricks. Brick pagodas emergence marked a stage where technological progress made it possible for man to built high-rise brick work, and their dvelopment further perfected masonry technique and enabled building technology to attain new heights. Though from the very start brick pagodas existed side by side with stone pagodas, at the enitial stage they were overshadowed by their wooden counterparts and stone counterparts, because masonry thechiques were then still rather primitive, while woodwork and stonework had already reached a fairly advaced stage. The pagodas in ancient Korea were closely related to the Chinese stupa, which consisted of three parts, namely, the base, the body and the spire. The fact was, soon after the stupas were introduced into Korea, the Korean stupas began to develop features of their own. Korean brick pagodas were made up of a single-storeyed square base, multi-storeyed square body with a small gate, and a steel post with several layers of lotus flower superimposed one on the other.

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Quality Design Support System based on Data Mining Approach (데이터 마이닝 기반의 품질설계지원시스템)

  • 지원철
    • Journal of the Korean Operations Research and Management Science Society
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    • v.28 no.3
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    • pp.31-47
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    • 2003
  • Quality design in practice highly depends on human designer's intuition and past experiences due to lack of formal knowledge about the relationship among 10 variables. This paper represents an data mining approach for developing quality design support system that integrates Case Based Reasoning (CBR) and Artificial Neural Networks (ANN) to effectively support all the steps in quality design process. CBR stores design cases in a systematic way and retrieve them quickly and accurately. ANN predicts the resulting quality attributes of design alternatives that are generated from CBR's adaptation process. When the predicted attributes fail to meet the target values, quality design simulation starts to further adapt the alternatives to the customer's new orders. To implement the quality design simulation, this paper suggests (1) the data screening method based on ξ-$\delta$ Ball to obtain the robust ANN models from the large production data bases, (2) the procedure of quality design simulation using ANN and (3) model management system that helps users find the appropriate one from the ANN model base. The integration of CBR and ANN provides quality design engineers the way that produces consistent and reliable design solutions in the remarkably reduced time.

Study on Philosophy and of counselor's Attitude of Solution Focused Counseling Approach (해결중심상담접근의 철학과 상담자태도에 관한 연구)

  • Rho, Myung-Sook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.8
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    • pp.3724-3731
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    • 2013
  • The purpose of this study was to find philosophy and counselor's attitudes of solution focused counseling approach. Research methods was to analyze the target literature on 'solution focus / principle; value; philosophy; attitude' through data retrieval around the books, academic papers, master thesis, Phd thesis. The results of this study are as follows. The philosophy of solution focused counseling approach is to center clients, to focus on 'effect', to base on social constructivism and to base on positive psychology. In addition, the counselor' attitudes of solution focused counseling approach is to have 'not-knowing' stance about Clients, to take the attitude of observation with sincere curiosity, to compliment the clients, to become a partner and a coach to practice solution focused counseling approach in various fields.

The Impact of Balanced Scorecard on Performance: The Case of Vietnamese Commercial Banks

  • TUAN, Tran Trung
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.1
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    • pp.71-79
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    • 2020
  • Balanced Scorecard (BSC) is one of basic contents of managerial accounting. Balanced Scorecard (BSC) will help the manager to measure and evaluate the operating performance in enterprises. Therefore, providing the theory base as well as in fact with regards to apply with Balanced Scorecard, impact of applying with Balanced Scorecard on the performance of company, from then providing for the managers with the base to promote on applying the Balanced Scorecard in Vietnamese Enterprises aimed to improve the operating performance of enterprises meaningfully and neccessary. However, balanced scorecard in general is a very new content in both theoretical and practice in Viet Nam. The study aims to explore the application with Balanced Scorecard in enterprises according to 4 perspective of Balanced Scorecard in Vietnamese commercial banks. In the dimension of this paper, SPSS 22 was used to collect and analysis data, basing on the results of 109 questionnaires of managers and head of department from Vietnamese commercial banks. Research have shown impact of Balanced Scorecard on the performance of Vietnamese commercial banks. This is the scientific basis for enterprises of Vietnam in general and Vietnamese commercial banks firms in particular have a successful application of balanced scorecard to improve the business performance.

Effect of the Welding Methods on the Characteristics of Overlaying Seat-surfaces of Engine Valves (엔진밸브 시트 표면의 오버레이층 특성에 미치는 용접법의 영향)

  • 이병영;최병길
    • Journal of Welding and Joining
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    • v.20 no.4
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    • pp.517-524
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    • 2002
  • An overlaying of the seating surfaces of engine valves by OAW, GTAW or PTA weldings are common practice. The OAW method of a lower torch energy density compared to GTAW and PTA methods produces smoother deposits but the pain size at the vicinity of the interface is increased remarkably up to $30~50{\mu\textrm{m}}$ (that of base metal is about $10\mu\textrm{m}$). It's grain coarsening and the solute dilution are related to the decarburizing during OAW could be minimized by reducing the preheating temperature and by maintaining the carbide precipitates in base metal prior to welding. The formation of columnar structures and carbide precipitation zone in the vicinity of the GTAW welded interface, because of the high heat concentration, causes weakened zone on the valve seat face. The width of the reaction boundary zone is about $50\mu\textrm{m}$ for PTA and GTAW overlaying, and about $150\mu\textrm{m}$ for OAW welding. The smaller width of the reaction boundary zone is the less the solute-dilution rate. Thereby PTA welding may be recommended for overlaying of the seating surfaces.

Conceptual Design of the Scroll Air Compressor for Fuel Cell (연료전지용 스크롤 공기압축기 개념설계)

  • Kwon, Tae-Hun;Ahn, Jong-Min;Kim, Hyun-Jin;Shim, Jae-Hwi
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.20 no.2
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    • pp.113-120
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    • 2008
  • Potential application of the scroll type machine to air compressor for fuel cell has been studied. Among the seven configuration factors which determine scroll wrap profile, the wrap thickness and the orbiting radius were chosen as two independent variables to generate various scroll wrap profiles. A conceptual design practice was conducted for scroll air compressor for SOFC with power output of 2 kW. With larger wrap thickness and orbiting radius, base plate area of the orbiting scroll becomes smaller, so is the axial gas force acting on the base plate, resulting in reduced thrust loss in spite of larger friction velocity. Performance analysis on the designed model showed that its total efficiency was 64.4% with the mass flow rate per unit compressor input of 0.00905 kg/(s kW) for the wrap thickness of 3.5 mm and the orbiting radius of 3.0 mm.

Determination of an Optimum Orbiting Radius for an Oil-Less Scroll Air Compressor

  • Kim, Hyun-Jin;Lee, Yong-Ho;Kwon, Tae-Hun
    • International Journal of Air-Conditioning and Refrigeration
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    • v.16 no.4
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    • pp.124-129
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    • 2008
  • Design practice has been made on an oil-less scroll air compressor as an air supply device for a 2 kW fuel cell system where air pressure of 2 bar and flow rate of 120 liter/min are required. Basic structure of the scroll compressor includes double-sided scroll wrap for the orbiting scroll driven by two crankshafts connected to each other by a timing belt. These features can eliminate thrust surface which otherwise would produce frictional heat and jeopardize reliable operation of the orbiting scroll and the scroll element's deformation as well. This study focuses on optimum scroll wrap design; orbiting radius has been chosen as an independent design parameter. As the orbiting radius changes, scroll sizes such as scroll base plate and discharge port diameters change accordingly. Gas compression-related losses and mechanical loss also change with the orbiting radius. With a scroll base plate diameter of 120mm at most and discharge port of at least 10mm, the orbiting radius should be within the range of 2.5-4.0mm. With this range of the orbiting radius, it was estimated by performance analysis that the compressor efficiency reached to a maximum of ${\eta}_c$=96% at the orbiting radius of $r_s$=3.5mm for the scroll wrap height-to-thickness ratio of h/t=5.

Power Control of Femto Base Station for Protecting Macrocell Users (매크로셀 사용자 보호를 위한 펨토셀 기지국의 전송전력 제어)

  • Jeong, Dong Geun;Kim, Yu Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.10
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    • pp.865-873
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    • 2013
  • In the cellular networks adopting femtocells, the macrocell users can suffer from severe interference by the femtocells. In this paper, we propose a distributed transmission power control scheme for femtocells to protect macrocell users. With the proposed scheme, when a macrocell user experiences outage due to severe interference, it informs the interfering femtocell base station (BS) of the outage occurrence, via the macrocell BS. Then, the femtocell BS reduces the transmission power to protect the macrocell user. The proposed scheme does not require too much control information among the macrocell BS, the macrocell users, and the femtocell BS. Moreover, the computational complexity in femtocell BS is very low. By using simulation, we show that the performance of the proposed scheme is good enough to use in practice, in spite of its simplicity.

A Development on the CAD/CAM System for High Efficiency Deep Drawing Transfer Die (고능률 디프 드로잉 트랜스퍼 금형 설계 및 제작을 위한 CAD/CAM 시스템)

  • 박상봉
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1998.06a
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    • pp.57-64
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    • 1998
  • The purpose of this research is to develop a CAD/CAM system for generation all kind of information such as, total drawing, sub assembly drawing, part drawing, detail drawing, part list, and NC data for machining by CNC lathe, Wire CUT, machining center. Through this study the CAD/CAM System for deep drawing transfer die in mechanical press process has been developed. The developed CAD system can generate the drawing of transfer die in mechanical press. Using these results from CAD system, it can generate the NC data to machine die's elements on the CAD system. This system can reduce design man-hours and human errors. In order to construct the system, it is used to automate the design process using knowledge base system. The developed system is based on the knowledge base system which is involved a lot of expert's technology in the practice field. Using AutoLISP language under the AutoCAD system, CTK customer language of SmartCAM is used as the overall CAD/CAM environment. Results of this system will be provide effective aids to the designer and manufacturer in this field.