• ETRI Journal
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• v.19 no.3
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• pp.141-168
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• 1997

The base station (BS) in the CDMA Mobile System (CMS) connects calls through the radio interface and is designed to provide mobile subscribers with high quality service in spite of mobile subscribers motions. The BS consists of multiple base station transceiver subsystems (BTSs), a base station controller (BSC) and a base station manager (BSM). This paper is concerned with the BSC and the BSM. The BSC is located between the BTSs and the mobile switching center (MSC) connected with the public network, and to mobile subscribers via the BTSs. The BSM provides operator-interfaces per the BS and takes responsibility of operation and maintenance (OAM) of the BS. Design of the BSC is based on two module types: functional module and unit module. The functional module is used to support new services easily and the unit module to increase the system capacity economically. Both modular types are easily achieved by inserting the corresponding modules to the system. Particularly, in order to efficiently support the soft handover which is one of CDMA superior advantages, the BSC adopts a large high-speed Packet switch connecting up to 512 BTSs, and thus mobile subscribers can be provided with soft handover in high probability. The BSM is based on a commercial workstation to support OAM functions efficiently and guarantee high reliability of the functions. The BSM uses graphical user interface (GUI) for efficient OAM functions of the BS.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.15 no.3
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• pp.197-212
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• 1990

This paper present a new design concept of a single chip 16-bit data path using the concept of modular design, the whole system is divided into several blocks which can be operated as an independent system itself. Making the internal blocks can act as a subsystem, it is possible to shorten design turn-around time, to be redesigned effectively, and to optimize the system performance. The designed system is data path. The data path is to manipulate 16-bit integer data. It is composed of aritmetic logic unit, register file, barrel shifter and bus circuit. The widths and lengths of gate in the circuit were determined using SPICE2. The results of circuit simulation were in good agreement with expected circuit characteristics.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.1
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• pp.120-128
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• 2000

One of the major limitations of productivity and quality in metal cutting is the machining accuracy of machine tools. The machining accuracy is affected by geometric errors, thermally-induced errors, and the deterioration of the machine tools. Geometric and thermal errors of machine tools should be measured and compensated to manufacture high quality products. In metal cutting, the machining accuracy is more affected by thermal errors than by geometric errors. This paper models of the thermal errors for error analysis and develops on-the-machine measurement system by which the volumetric error are measured and compensated. The thermal error is modeled by means of angularity errors of a column and thermal drift error of the spindle unit which are measured by the touch probe unit with a star type styluses and a designed spherical ball artifact (SBA). Experiments, performed with the developed measurement system, show that the system provides a high measuring accuracy, with repeatability of $\pm$2${\mu}{\textrm}{m}$ in X, Y and Z directions. It is believed that the developed measurement system can be also applied to the machine tools with CNC controller. In addition, machining accuracy and product quality can be improved by using the developed measurement system when the spherical ball artifact is mounted on the modular fixture.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.38 no.1
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• pp.27-34
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• 2001

The multiplication algorithm using the primitive irreducible trinomial $x^m+x+1$ over $GF(2^m)$ was proposed by Mastrovito. The multiplier proposed in this paper consisted of the multiplicative operation unit, the primitive irreducible operation unit and mod operation unit. Among three units mentioned above, the Primitive irreducible operation was modified to primitive irreducible trinomial $x^m+x+1$ that satisfies the range of 1$x^m,{\cdots},x^{2m-2}\;to\;x^{m-1},{\cdots},x^0$ is reduced. In this paper, the primitive irreducible polynomial was reduced to the primitive irreducible trinomial proposed. As a result of this reduction, the primitive irreducible trinomial reduced the size of circuit. In addition, the proposed design of multiplier was suitable for VLSI implementation because the circuit became regular and modular in structure, and required simple control signal.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.188-194
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• 2011

The purpose of this paper is to explain the implementation method in order to enhance stability and reliability of embedded system. In this research, Texas Instrument (TI)'s TMS570 MCU(Micro Controller Unit) is used to satisfy the standard of stability that is IEC 61508. IEC 61508 suggest SIL(Safety Integrity Level) from 1 to 4 and TMS570 is satisfied SIL3. Also, TMS570 can provide several stability functions can be used in realtime system. To use such functions, this paper suggest the solution about the defect that can be used in realtime system. In basic way TMR(Triple Modular Redundancy) suggested in addition to explain about the way to improve safety and reliability. Also this paper will suggest the method that reinforce the stability of calculation by using multiplex voter and memory.

• Proceedings of the IEEK Conference
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• 2003.07d
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• pp.1263-1266
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• 2003

One of the hardest problems in implementation of digital neural network are extension of synapses and programmability for relocating neurons. This paper Proposes a new hardware structure to solve these problems. The proposed structure can reconfigure network connections without alteration of basic design, and extend number of synapses attached to one neuron. Also, it is possible to extend the number of neurons and layers by connecting many MPUs(Modular Processing Unit). Generality and extensibility are verified by composing various kinds of Perceptorn and Kohonen networks using the architecture proposed in this paper and the verification performances compares well with HDL simulation results as well as the results of C modelling.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.390-394
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• 2001

A dynamic simulation model for the brush less dc (BLDC) motor drives using Matlab is presented. In this model, an entire BLDC motor drive, including power conversion unit, BLDC motor, and speed/torque control system, is investigated. Especially, the PWM inverter is modeled using switching function concept, so that the detailed voltage and current waveforms, such as line-to-line voltages, inverter input current, ac line current, and switch/diode currents, can be obtained and average/rms ratings of the components can be easily calculated. Also, the proposed model is made into modular blocks and it can be easily extended to other ac motor applications with a little modification. The detailed modeling method is explained and its actual implementation is described. The validity of the proposed model is verified by various simulation results.

• Journal of Korean Academy of Nursing
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• v.25 no.1
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• pp.80-87
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• 1995

The critical problem of nurse scheduling in the hospital is determining the day-to -day shift assignments for each nurse for the specified period in a way that satisfies the given requirements of the hospital. As nurse scheduling involves many factors and requirements, manual scheduling requires much time and effort to produce an adequate schedule. A PC - based decision support system, developed in Turbo - C/sup ++/, for nurse scheduling was introduced. The system is composed of 4 sub-systems : 1) Entering basic information for each nursing unit : 2) Generation of an appropriate initial schedule and revised schedule for a given period, maximally satisfying each nurse's duty requests : 3) Provision of variety of statistical information, and 4) Help messages for each modular function. Icons and a mouse are used for easier graphic user interface and reducing the need for typing efforts. This system can help nurses develop quick and easy schedule generation and allow more time for the patient care.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1232-1233
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• 2011

본 개발은 에너지 수요관리, 전력품질감시, 전기안전감시 및 설비감시가 가능한 정보통신실 기반설비용 전원분배장치 운용 S/W 개발에 관한 것으로써, 분전반 단위의 전력 및 에너지 관련정보, 전기기기 및 에너지 상태 정보, 장치 상태 정보를 실시간으로 취득 원격에서 감시 및 분석/통계 할 수 있다.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.496-499
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• 1999

This paper describes a medular neural network(MNN) for a vision system which tracks a given object using a sequence of images from a camera unit. The MNN is used to precisely recognize the given robot endeffector and to minize the processing time. Since the robot endeffector can be viewed in many different shapes in 3-D space, a MNN structure, which contains a set of feedforwared neural networks, co be more attractive in recognizing the given object. Each single neural network learns the endeffector with a cluster of training patterns. The training patterns for a neural network share the similar charateristics so that they can be easily trained. The trained MNN is less sensitive to noise and it shows the better performance in recognizing the endeffector. The recognition rate of MNN is enhanced by 14% over the single neural network. A vision system with the MNN can precisely recognize the endeffector and place it at the center of a display for a remote operator.