• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.1
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• pp.223-231
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• 1994

When manufacturing mold dies, an operation sheet is required for each part of the mold dies. The consistent estimation of standard operation time in the operation sheet is difficult, because the estimation is mainly based on subjective judgement. In order to resolve it, concept of feature is introduced in this study. For CAD/CAPP integration, feature technology is being implemented to represent geometrical and technological information of part drawings. A feature database has already been designed, and then used to generate data for process and operation planning modules. Related to this former research, standard operation time is calculated using the feature information and tables used in a real factory.

• Explosives and Blasting
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• v.33 no.3
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• pp.14-20
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• 2015

Tunnel blasting that plays the most important role in the construction of a drill & blast tunnel, shows a big difference in operation time according to various factors such as rock mass quality, tunnel dimension, machine performance, and the skill level of tunnel crews. This paper analyzes the differences between the time calculated by the standard of estimate and actual operation time based upon field investigations on blasting operation time in three tunnels of Korea. The result shows that actual blasting time is generally about 8%~16% less than the standard of estimate in cases that normal operations are performed. If the time delayed by unforeseen situations is included, however, it is presumed that the number of cases that actual operation time exceeds the standard of estimate are considerable. This study aims to help make a judgement over the appropriacy of the standard of estimate through continuous investigations on actual operation time, as well as improve the productivity of tunnel excavation.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.3
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• pp.332-341
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• 2013

SCADA RTU is a remote control unit equipped in substations for automatic operation of a power system. The RTU monitors and measures the operation status of remote substations to transmits the signals to upper SCADA system and receives control command signals from dispatch center to actuate corresponding apparatus. The RTU receives the standard time from GPS receiver to synchronize the times for all devices and acquires the status event of power apparatus using DIM. Without the time synchronization between GPS and RTU, stable operation of the power system and accurate analysis of the system fault are impossible due to the time error of SOE. In this paper, a test is performed to identify if the operation time of SCADA RTU DIM coincides with the standard time. And we tried to find the reason of error, to minimize the time discrepancy. Through this study, RTU operation time could be synchronized with the standard time within 10[ms] to improve the reliability of SOE data.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.33
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• pp.11-27
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• 1995

This study sets a goal of establishing work standard and standard time in a machine tool process consisted of high-priced NC machine tools. Firstly, the theories of work standard and standard time in the field of NC machine tools are studies. Secondly, the theories are actually applied to a manufacturing company; work standard sheets are developed and applied to a machining center haying low operation rate, and then the increase in productivity is compared. Finally, problems to be studied later in relation to work standard and standard time are presented.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.4 no.5
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• pp.27-42
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• 1981

The object of this paper is to Study the work measurement which is one of the principal technique in work study for the improvement of Productivity in the foundry industry. Most of domestic mechanical enterprise using the expensive foreign machinerise is inoufficient for the standardization of the operation method and time. Therefore, the improvement of operation and productivity through the introduction of the work measurement is an urgent task. Therefore, this paper is contribute to the improvement of operation and to reduce the loss time through the application of the work measurement based on the case study conducted at W-Foundry Corporation. The summary of this study is follows; 1. The measurement of operation efficiency can be accomplished by the standard time. 2. The detailed causes and counter-proposal of loss time can be established, 3. More than 50% of loss time is attributed to c/p.

• IE interfaces
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• v.6 no.2
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• pp.91-101
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• 1993

Developed in this paper is a standard time data for shirt sewing operations in the apparel-making industry. Since this data is made of formula developed for each unit operation and includes the formula for the machine time calculation, users could use it for obtaining the normal or standard time without any special efforts. In addition, this data handles the variations due to the design changes of a shirt through the parameters in the formula. compared with the MTM-1. The standard time data developed is shown to be easier and faster in determining the standard time with acceptable accuracy.

• Journal of the Institute of Convergence Signal Processing
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• v.10 no.4
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• pp.280-288
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• 2009

In this paper, we developed new time information recording module of VSI (VLBI Standard Interface) format by analyzing the Mark5B recorder control and operation software with 1Gbps speed, which is able to record the weak signal of space radio source, through the Korean VLBI Network (KVN). The control and operation software of high-speed recorder consists of 2 kinds of software, which is that it can operate RAID control board by controlling large capacity HDD drive and the network control and operation. Especially, core software in high-speed recorder is able to output the results after performing and analyzing the input command. Through the analysis of control and operation software, new time information recording module, which is needed to process the observed data for correlation, is developed. New developed time information recording module can record the time information together after checking the interrupt of 1PPS(Pulse Per Second) input signal when the observed data will be recorded. To verify the normal operation of the developed time information recording module, we performed the real observation test and confirmed the effectiveness of developed software through analyzing the recorded observation data.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.595-600
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• 2007

Greater expansion and more frequent operation of the railroad transportation system anticipated due to its characteristics including low cost, safety and mass transportation. Recently, effects on the railway structures due to expansion of newly constructed road, construction of subway, city gas pipeline, communication network, electric power network and construction of other railway underground crossing in accordance with urban planning and organization has influenced safe operation of trains. Accordingly, standard for selection of construction method that will enable construction of more economical and rational subway underground crossing structures by preventing problems occurring at the time of above construction works and accidents in safe operation of trains due to construction in advance is definitively necessary. Although there are numerous construction methods that can be applied at the time of construction of railway underground crossing, there are much difficulties in selection of appropriate construction method that considers characteristics of each construction method on non-excavation type construction method, train operation plan of number of operational routes and on-site circumstances. Therefore, this research aims to present rational standard for selection of construction method for such, and standard for slowdown speed and interception of train when passing the areas of slowdown in sectors under construction.

• IE interfaces
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• v.11 no.3
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• pp.103-114
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• 1998

This paper suggests a computer software system which generates standard times for assembly products. The system called "computer aided logical system for standard times(CALS4ST)" incorporates a modified bill of materials, BOM4ST(BOM for standard time) to deal with auxiliary operations which are not directly related to parts and assemblies listed in the standard BOM. Typical examples of the operations include inspection, adjustment, and repairing works to be done before or after assembly operations. Once standard time data bases for both the part assembly operations and the auxiliary operations are set up, the system relates the BOM4ST to the standard time data bases so as to calculate the standard time for a assembly part concerned. According to the structure of parts and auxiliary operations in the BOM4ST, their standard times stored in the data bases are to be sequentially added up considering the specified assembly-operation characteristics. To illustrate the feasibility of the system, the case study of L company is provided.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.5D
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• pp.649-656
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• 2011

The increase in the traffic demand and behavioral pattern of its use reached the limit for the only means of road construction to bear; thus the multilateral efforts to find a solution to this problem together with the examination and research on this issue, among which the most representative strategy is Ramp Metering System controlling access traffic volume to connection roads. The operation standard and running time was re-established in consideration of geographical conditions and traffic circumstances by considering the standard of operation and running time of the currently operated Jangsu- Jungdong section of the outer ring expressway of Seoul. For this purpose, this research analyzed the operative standard of RMS home and abroad and suggested a new operative standard of ramp metering through the analysis of break points.