• 웰빙융합연구
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• 제4권3호
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• pp.1-9
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• 2021

Purpose: This study was conducted to develop a module with higher removal efficiency and effectiveness by adapting two or more deodorization techniques for main cause of odor pollution exposed citizen living near water treatment facilities. Research design, data and methodology: To consider the standard, unity, electrical wire, compatibility of detachable device by installing two types of dry deodorization device within one module for easy replacement. Complex odor, H₂S, NH₃ were collected from sewage treatment facilities for evaluation of deodorization device. Results: Using the developed application in this study, removal efficiency of complex odor, H₂S, NH₃ were 93%, 100%, 82%, respectively. Conclusions: The H₂S removal efficiency of deodorization device was higher than bio-filter system, which were currently used by sewage treatment. Further, the device should be considered for use in efficient odor removal system.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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• pp.195-208
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• 1990

Flexible Manufacturing System(FMS) is an integrated, computer controlled complex of automated material handling devices and numerically controlled machine tools that can simultaneously process medium-sized volumes of a variety of part types. This paper discusses planning problems that can be solved for efficient use of an FMS and present an integrated decision support system for FMS production planning and scheduling problems. FMSDS(Flexible Manufacturing Systems Decision Support System) consists of data handling modules, part selection module, loading module, load adjusting module, scheduling module and simulation module etc. This paper presents the solution methodology of each subproblems and integrated interfaces between subproblems using hierarchical approaches and loop controls considering the relationships between subproblems. A case study by this model is presented.

• 웰빙융합연구
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• 제5권4호
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• pp.51-56
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• 2022

Purpose: By applying an ultrasonic mechanical device to the liquid fertilizer storage in the pig dropping treatment plant, the initial odor of the odor source is reduced, and the air dilution drainage of the complex odor is fundamentally recognized to facilitate odor treatment on the mechanical and chemical biological treatment devices at the rear. Research design, data and methodology: The odor concentration on the site boundary was measured to confirm the state of reduction. In order to prevent the spread of odor from the collection of the pig dropping treatment plant, it was measured by installing an ultrasonic generator inside the installation wall after installing the sealing wall. Results: The average value of the March and April measurement data remained close to neutral at 8.2 after 8.6 treatment before pH treatment, decreased 97.3% from 462 mg/L before SS treatment to 10.5 mg/L after treatment, and the composite odor was reduced by 85% from 20 to 3 before treatment. It was confirmed that ammonia (NH3) was reduced by 99% from 5.8 ppm to 0.09 ppm, and general bacteria were also reduced by 99% from 3,200 CFU/mL to 57 CFU/mL Conclusion: Applying the ultrasonic air ejector hybrid system and zigzag air complex module development product to resource circulation centers or sewage treatment facilities is thought to reduce inconvenience to residents due to odors caused.

• 전력전자학회논문지
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• 제21권4호
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• pp.335-342
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• 2016

This paper proposes an energy storage-assisted, series-connected module-integrated power conversion system that integrates a photovoltaic power conditioner and a charge balancing circuit. In conventional methods, a photovoltaic power conditioner and a cell-balancing circuit are needed for photovoltaic systems with energy storage devices, but they cause a complex configuration and high cost. Moreover, an imbalanced output voltage of the module-integrated converter for PV panels can be a result of partial shading. Partial shading can lead to the fault condition of the boost converter in shaded modules and high voltage stresses on the devices in other modules. To overcome these problems, a bidirectional buck-boost converter with an integrated magnetic device operating for a charge-balancing circuit is proposed. The proposed circuit has multiple secondary rectifiers with inductors sharing a single magnetic core, which works as an inductor for the main bidirectional charger/discharger of the energy storage. The secondary rectifiers operate as a cell-balancing circuit for both energy storage and the series-connected multiple outputs of the module-integrated converter. The operating principle of the cell-balancing power conversion circuit and the power stage design are presented and validated by PSIM simulation for analysis. A hardware prototype with equivalent photovoltaic modules is implemented for verification. The results verify that the modularized photovoltaic power conversion system in the output series with an energy storage successfully works with the proposed low-cost bidirectional buck-boost converter comprising a single magnetic device.

• 반도체디스플레이기술학회지
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• 제3권1호
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• pp.21-26
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• 2004

Recently with the development of power switching device and DSP which has peripheral devices to control AC servo system, the servo technology has met a new development opportunity. Those things make it possible to reduce the time of developing a AC servo system. Fixed point DSP such as TMS320F240x, and TMS320F28x series have a disadvantage in calculating floating number where TMS320C32 or TMS320C31 are floating point DSP. However they usually become a complex hardware system to implement the AC servo system and it increases the cost. In this study, a DSP based AC servo system with a 3-phase PMSM is proposed. The newly produced DSP TMX320F28l2-version C which has the performance of fast speed, 150MIPS, and a rich peripheral interface such as a 12bit high speed AD converter, QEP(Quadrature Encoder Pulse) circuit, PDPINT(Power Drive Protect Interrupt), SVPWM module and dead time module are used. This paper presents a method to overcome fixed point calculating using scaling all parameters. Also space vector pulse width modulation (SVPWM) using off-set voltage and a digital PI control are implemented to the servo system.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 추계종합학술대회
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• pp.284-287
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• 2000

최근 개발되고 있는 의료기기들은 사용자의 상호 복합적인 요구사항을 반영하기 위하여 모듈(Module)화되는 추세이다. 이는 환자의 상태를 관찰, 진단, 처리를 위해 여러 기기들로부터 데이터를 수집하고, 이에 따르는 동작을 제어하기에 가장 효율적인 방법이기 때문이다. 이와 같은 모듈화 경향은 여러 개의 단일 시스템들을 쉽게 통합 관리할 수 있기 때문에 더욱 일반화되고 있다. 본 연구에서는 모듈화된 의료장비들을 하나의 통신 시스템으로 묶어 중앙 집중형 제어를 할 수 있는 통신 프로토콜을 구현하였다. 본 연구에서 구현된 시스템은 모든 기기들을 제어하고 통신을 관장하는 하나의 마스터(Master) 모듈과 각각의 의료기기들에 해당되는 여러 개의 슬레이브(Slave)모듈로 구성된다. 각 모듈간 통신은 데이터의 정확한 송, 수신을 위해 여러 동기 직렬 통신방식 중 SPI(Serial Peripheral Interface)를 사용하였다. 모든 통신은 패킷(Packet)형태로 이루어지고, 통신중 에러를 검출할 수도 있다. 또한, 마스터 모듈은 자동으로 특정 슬레이브 모듈외 연결 및 동작 유무를 알 수 있는 PNP(Plug And Play)기능이 있다. 본 연구에서 구현된 프로토콜온 컴퓨터와 연결하여 데이터 전송 확인을 통해, 1Mbps이상의 빠른 속도에서 정화한 송, 수신이 이루어지며, 인공호흡기와 같은 실시간 데이터의 송, 수신이 이루어져야하는 의료장비에서도 모듈이 수행하는 본래의 일에 방해하지 않고 실시간 통신이 이루어지는 것을 실제 호흡기 시스템에 적용하여 확인하였다. 또한, 중앙 집중형 제어에 의한 다양한 기능을 편리하게 구현할 수 있었다.이다.ure scheme based on KCDSA which is a domestic digital signature scheme and it apply a electronic cash system. In particularly a proposed electronic cash system have an anonymity control ability which trace a user who make use a electronic cash illegally in association with a trusted center.estigation and explain how our tool can be further enhanced.door playground facilities. On the basis of the site investigation the interview and the indoor education program for physically challenged children the author completed an outside play program. Each item in this program was classified as belonging to either a "sense play" program or and "exercise play" program. Finally, the author designed suitable play equipment for physically challenged children corresponding to each item in the exercise

• 전자공학회논문지A
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• 제28A권10호
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• pp.774-781
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• 1991

A communication network protocol among programable devices built-i manufacturing field, MAP (Manufacturing Automation Protocol), has to provide the job transfer service carrying out a lot of jobs distributively, and the MMS( manufacturing message specification) defines the above application layer protocol. In this paper user software required in job transfer was implemented. So as to provide each service with compatibility and extension, each module was designed according to the functions. A method is selected in double-assigning their domain and program applicable even in complex process, which loads and proceeds several programs sequentially. In order to confirm the logical validity of the designed protocol, local applying test is accomplished for the application layer of response station. Modelling the job flow process, each serice module is verified with the I/O primitives.

• 한국안전학회지
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• 제31권1호
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• pp.48-53
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• 2016

This paper deals with analysis of complex grounding system using electromagnetic simulation method. Electrical devices could be damaged by transient voltage such as a lightning surge. Therefore the measures to protect the equipments from transient, such as a lightning are required. The ground system is important in this respect. The representative parameter of grounding system performance is earth ground resistance. Precise prediction of earth resistance is required, because it is difficult to modify and change after the completion of the grounding system construction. Numerical modeling is often used in numerical analysis to identify the electrical characteristics of the grounding system. However complex systems are difficult to predict grounding characteristics by numerical analysis. If the total electric field of the earth in general is similar to the antenna model, in that the incident electric field and expressed as a sum of the scattering field. In this study, the electromagnetic field simulation tool "ANSYS HFSS" module containing the antenna model was used to analyze performance of ground system. Both the simple and complex grounding system were analyzed by simulation tool and experimental method. As a result simulation method is effective to predict performance of a complex ground system.

• Journal of Electrical Engineering and Technology
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• 제3권2호
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• pp.271-275
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• 2008

The MAM(Megasonic Agitated Module) has been fabricated for improving the characteristics of wet etching. The characteristics of the MAM are investigated during the wet etching with and without megasonic agitation in this paper. The adoption of the MAM has improved the characteristics of wet etching, such as the etch rate, etch uniformity, and surface roughness. Especially, the etching uniformity on the entire wafer was less than ${\pm}1%$ in both cases of Si and glass. Generally, the initial root-mean-square roughness($R_{rms}$) of the single crystal silicon was 0.23nm. Roughnesses of 566nm and 66nm have been achieved with magnetic stirring and ultrasonic agitation, respectively, by some researchers. In this paper, the roughness of the etched Si surface is less than 60 nm. Wet etching of silicon with megasonic agitation can maintain nearly the original surface roughness during etching. The results verified that megasonic agitation is an effective way to improve etching characteristics of the etch rate, etch uniformity, and surface roughness and that the developed micromachining system is suitable for the fabrication of devices with complex structures.

• Journal of Power Electronics
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• 제16권4호
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• pp.1316-1323
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• 2016

Multilevel inverters (MLIs) have been preferred over conventional two-level inverters due to their inherent properties such as reduced harmonic distortion, lower electromagnetic interference, minimal common mode voltage, ability to synthesize medium/high voltage from low voltage sources, etc. On the other hand, they suffer from an increased number of switching devices, complex gate pulse generation, etc. This paper develops an ingenious symmetrical MLI topology, which consumes lesser component count. The proposed level dependent sources concoction multilevel inverter (LDSCMLI) is basically a multilevel dc link MLI (MLDCMLI), which first synthesizes a stepped dc link voltage using a sources concoction module and then realizes the ac waveform through a conventional H-bridge. Seven level and eleven level versions of the proposed topology are simulated in MATLAB r2010b and prototypes are constructed to validate the performance. The proposed topology requires lesser components compared to recent component reduced MLI topologies and the classical topologies. In addition, it requires fewer carrier signals and gate driver circuits.