• Proceedings of the KSR Conference
• /
• 2010.06a
• /
• pp.344-351
• /
• 2010

On last year's KSR conference, the general of systems engineering technology was introduced on the focus that the SEMP(Systems Engineering Management Plan) being applied for a national project of 'Urban Maglev Program'. Since this SEMP covers very wide work scopes of 'plan, application, control of the program', 'design, analysis, test & evaluation of the system', and 'special engineering activities', it is very important that the tasks and responsibilities of all participants of the project, involving the tasks to collaborate between them, are clearly defined and described. By the point, the updating of SEMP should be done continuously. In this paper, the updating points and typically the management plan of TPM (Technical Performance Measurement), which is more concretely defined, will be explained.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2012.05a
• /
• pp.211-212
• /
• 2012

Over the years, the recovery of the domestic construction market, which does not appear on the reverse, but rather due to a surge of construction materials cost of the construction sector is experiencing greater difficulties. Cement raw materials in the manufacturing process, if some of the waste recycling, cites quality control for products and measures for the thorough management is needed. In this study, three companies of the past four years in the production of cement against doejin physical performance test results conducted yearly and seasonal trends by analyzing changes in the years to review the cement for cement to utilize as a basis for management points is.

• Proceedings of the Korea Contents Association Conference
• /
• 2008.05a
• /
• pp.784-787
• /
• 2008

Growing needs for efficient management of water resources urge the joint operation of dams and integrated management of whole basin. As one of the tools for supporting above tasks, this study aims to constitute a hydrologic model that can simulate the streamflow discharges at some control points located both upper and down stream of dams. One of the currently available models is being studied to be applied with a least effort in order to support the ongoing project of KWATER (Korea Water Resources Corporation), "Establishment of integrated operation scheme for the dams in Han River Basin".

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.10 no.4
• /
• pp.133-142
• /
• 2014

The least mean square(LMS) algorithm has been popular owing to its simplicity, stability, and availability to implement. But it inherently has a problem of slow convergence speed, and the presence of a transfer function in the secondary path following the adaptive controller and the error path has been shown to generally degrade the stability and the performance of the LMS algorithm in applications of acoustical noise control. In general, in order to solve these problems, the filtered-x LMS (FX-LMS) type algorithms can be used and the bi-directional Filtered-x LMS(BFXLMS) algorithm is very attractive among them, which increase the convergence speed and the performance of the controller with nearly equivalent computation complexity. In this paper, a mathematical analysis for the BFXLMS algorithm is presented. In terms of view points of time domain, frequency domain, and stochastic domain, the characteristics and stabilities of algorithm is accurately analyzed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.29 no.6
• /
• pp.613-620
• /
• 2011

In order to perform scientific evaluation of dredge results, it is needed to construct the system which is able to manage and evaluate the work process by monitoring in real-time the dredge process such as dredge ship position, dredge depth and dredge volume. This research aims to develop the hydrographic dredge surveying system adding water depth measurement method to both precise positioning and navigation methods using GPS, which allows a high rate of measurement and long distances between the control point and dredging points, operate in all weather conditions, and does not require line of sight to points. We constructed Beacon DGPS-based hydrographic dredger guidance and position management system and developed the operation program which makes the dredge operation perform as monitoring work situation in real-time. It is expected that this developed system will be able to contributes to reducing ultimately the cost in hydrographic dredging or hydrographic construction industries.

• Journal of Food Hygiene and Safety
• /
• v.11 no.3
• /
• pp.177-187
• /
• 1996

Time-temperature relationship and microbiological quality were assessed and critical control points were identified through hazard analysis during the phases of production in two different packaged meals (Dosirak) manufacturing establishments (A, B:Kim Pab). Microbiological tests on foods, equipments and utensils were done according to standard procedures and included total plate count, coliforms and fecal coliforms. The results of the study are summarized as follows : time-temperature control management was needed because time-temperature abuse more than 8 hours at dangerous temperature zone (5-6$0^{\circ}C$) was observed from pre-preperation to distribution phase; Poor sanitary practices of employees were observed in hand washing and using disposable gloves; Microbiological analysis results of equirpments and utensils showed possible cross-contamination risks when foods were contacted with them; Kim Pab needed thorough quality control because it included various mixed ingredients of cooked and uncooked and had many apportunities of cross-contamination either by equipments or hands through whole production processes.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.23 no.3
• /
• pp.19-30
• /
• 1978

Use of herbicides in Korean agriculture has increased rapidly in recent years accompanying with ever-increasing pressure of farm labor shortage. Herbicides occupied already the second place in the rank of pesticides consumption in 1977. The agricultural experiment stations have carried out over 50 trials of chemical weed control each year since 1968. These research works and registration trials contributed much to the present wide use of herbicides. The pesticide management act amended in 1977 requires reevaluation of pesticides for their efficacy every 5 year-term. However, the development of sound weed control program and recommendations has been hempered very much by the lack of qualified workers of weed control research in agricultural experiment stations and in the institute for pesticide registration trial. Critical review of the past research works on herbicide evaluation and the present status indicates strong need for 1) the characterization of the nature of local and national weed problem, 2) the improvement of ability of the staffs in charge of weed control research through appropriate training on the basics and experimental techniques, and 3) organization and activities of weed control research committee. Furthermore, the present article attempts to clarify commonly misled points in the establishment of herbicide evaluation plan, in the design and execution of field trials, and in the assessment of trial results of the past works from the viewpoint of the basic principles with some case studies for resolution of specific enigmas.

• Korean Journal of Health Education and Promotion
• /
• v.27 no.1
• /
• pp.49-60
• /
• 2010

Objectives: The purpose was to evaluate the effectiveness of participatory road safety education program for the lower grade in elementary schools. This program was developed based on the Activated Health Education model. Methods: Study design was compromise experimental group pre-post design. 456 students in 8 schools were nonrandomly assigned to study group(n=224) or control(n=232). The students finished self-administered questionnaire before and after education. Collected data was analyzed by using the SPSS. Results: 1. The common relevant factors in road safety knowledge and attitude were 'residential state' and 'experience of traffic accident'. 2. The knowledge showed that the case and control scored at 6.48 and 6.41 points before. After this intervention, the case and control scored at 8.38 and 6.51. The difference of the case was significant(p<0.001). 3. The attitude showed that the case and control scored at 19.67 and 19.63 before. After this, the case and control scored at 19.86 and 19.63. The difference of the case was significant(p<0.05). Conclusion: In order to implement the road safety education, children's socio-demographic characteristics were considered. Because this education was effective in both improving knowledge and attitude and bringing interest, various participatory program will be applied in road safety education for children.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.44 no.3
• /
• pp.86-97
• /
• 2021

As mechatronic systems have various, complex functions and require high performance, automatic fault detection is necessary for secure operation in manufacturing processes. For conducting automatic and real-time fault detection in modern mechatronic systems, multiple sensor signals are collected by internet of things technologies. Since traditional statistical control charts or machine learning approaches show significant results with unified and solid density models under normal operating states but they have limitations with scattered signal models under normal states, many pattern extraction and matching approaches have been paid attention. Signal discretization-based pattern extraction methods are one of popular signal analyses, which reduce the size of the given datasets as much as possible as well as highlight significant and inherent signal behaviors. Since general pattern extraction methods are usually conducted with a fixed size of time segmentation, they can easily cut off significant behaviors, and consequently the performance of the extracted fault patterns will be reduced. In this regard, adjustable time segmentation is proposed to extract much meaningful fault patterns in multiple sensor signals. By considering inflection points of signals, we determine the optimal cut-points of time segments in each sensor signal. In addition, to clarify the inflection points, we apply Savitzky-golay filter to the original datasets. To validate and verify the performance of the proposed segmentation, the dataset collected from an aircraft engine (provided by NASA prognostics center) is used to fault pattern extraction. As a result, the proposed adjustable time segmentation shows better performance in fault pattern extraction.

• Journal of Institute of Control, Robotics and Systems
• /
• v.7 no.11
• /
• pp.962-966
• /
• 2001

The major problem at a branch point for point-to-multipoint available bit rate(ABR) services in asynchronous transfer mode (ATM) networks is how to consolidate backward resource management(BRM) cells from each branch for a multicast connection. In this paper, we propose an efficient feedback consolidation algorithm based on an adaptive dynamic threshold(ADT) to eliminate the consolidation noise and the reduce the consolidation delay. The main idea of the ADT algorithm lies in that each branch point estimates the ABR traffic condition of the network through the virtual queue estimation and the transmission threshold of the queue level in branch points is adaptively controlled according to the estimation. Simulation results show that the proposed ADT algorithm can achieve a faster response in congestion status and a higher link utilization compared with the previous works.