• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.151-159
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• 2003

This paper presents a new DFA methodology to estimate the standard assembly time and evaluate the assemblablity of a product. The assembly time is estimated with some decision and influencing factors of assembly using motion analysis. The assemblability is evaluated using weights of the decision and influencing factors and assembly difficulty scores, and the tables that include the time and score of assembly are suggested. Finally, a new DFA system supporting the DFA is implemented to help designers to analyze the product during the design process in concurrent engineering.

• IE interfaces
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• v.6 no.2
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• pp.19-35
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• 1993

This paper presents the development of a knowledge-based expert system to assist for designer in the process of designing products for easier assembly. The developed expert system for supporting assembly-oriented product design, which is named as DFA-MASTER, consists of two subsystems such as "Assembly Method Selection System" which provides feasible assembly methods to designer and "DFA-Analysis System" which provides guidelines to improve assemblability of products in the early stage of product design. The developed system is interfaced with AutoCAD system and can be run under PC environments. By using DFA-MASTER, designer can obtain feasible assembly methods which have high assemblability under the given asssembly conditions and also evaluate the assemblability of part feature or product structure.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1075-1080
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• 2009

Recently, the building construction industry has been forced to cope with lack of skilled labor. A robot-based construction automation system should help overcome crucial troubles which may be caused by this phenomenon. In particular, it is vital to propose design for automation (DFA). Quality function deployment (QFD) is applied a systematic aid in determining the design reflecting customer's needs. This study employs the QFD approach to plan the component designs of an effective automation process, and presents the development process of DFA with an illustrative project. As a result, the study identifies the developers' design requirements for automated construction and weights them by their importance indices.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.133-141
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• 2014

An efficient method for reducing power consumption in pipelined deep packet inspection systems is proposed. It is based on the observation that the number of memory accesses is dominant for the power consumption and the number of accesses drops drastically as the input goes through stages of the pipelined AC-DFA. A DPI system is implemented where the operating frequency of the stages that are not frequently used in the pipeline is reduced to eliminate the waste of power consumption. The power consumption of the proposed DPI system is measured upon various input character set and up to 25% of reduction of total power consumption is obtained, compared to those of the recent DPI systems. The method can be easily applied to other pipelined architecture and string searching applications.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.4
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• pp.610-617
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• 1987

This thesis is concerned with fault-tolerance of a B-net (Beta-network) which is a kind of interconnection network in the multicomputer system. In this paper, a method for obtaining Maximal Tolerable Fault Set(MTFS) of link line connecting switching elements in the arbitrary B-net is presented. Using this method, it is seen that testing of DFA capability is possible when s-a-faults of link line occur, and criterion for determining degree of fault- tolerance of a B-net in terms of link line is introduced.

• Journal of Drive and Control
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• v.19 no.4
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• pp.54-61
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• 2022

This is a basic study analyzing emissions of an agricultural tractor during tillage operations. In this study, CO, THC, NOx, and PM considered as emission factor were analyzed during plow and rotary tillage operation by the tractor. Engine torque and rotational speed were measured through ECU. Engine power was calculated using engine torque and rotational speed. The emissions was calculated based on the number of units, rated power, load factor, and operating time. Results showed that the load factor was calculated almost twice, which was higher than 0.48. It was also observed that the emission of the tractor was variable for different agricultural operations because tractor loads were different based on operations. There was a difference in emissions due to differences in plow and rotary working hours. To estimate the emission of agricultural tractor based field operations in detail, it is necessary to consider TAF (Transient Adjustment Factor) and DFA (Deterioration factor). In the future, TAF and DFA will be considered to estimate emissions of the agricultural tractor. Finally, results of this study can contribute to the literature to estimate tractor emissions accurately.

• Journal of KIISE:Databases
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• v.35 no.4
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• pp.307-318
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• 2008

One of the primary issues confronting XML message brokers is the difficulty associated with processing a large set of continuous XPath queries over incoming XML seams. This paper proposes a novel system designed to present an effective solution to this problem. The proposed system transforms multiple XPath queries before their run-time into a new region-based data structure, called an XP-table, by sharing their common constraints. An XP-table is matched with a stream relation (SR) transformed from a target XML stream by a SAX parser. This arrangement is intended to minimize the runtime workload of continuous query processing. Also, system performance is estimated and verified through a variety of experiments, including comparisons with previous approaches such as YFilter and LazyDFA. The proposed system is practically linear- scalable and stable for evaluating a set of XPath queries in a continuous and timely fashion.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.1
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• pp.76-85
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• 2010

In general, anesthetic depth is evaluated by experience of anesthesiologist based on the changes of blood pressure and pulse rate. So it is difficult to guarantee the accuracy in evaluation of anesthetic depth. The efforts to develop the objective index for evaluation of anesthetic depth were continued but there was few progression in this area. Heart rate variability provides much information of autonomic activity of cardiovascular system and almost all anesthetics depress the autonomic activity. Novel monitoring system which can simply and exactly analyze the autonomic activity of cardiovascular system will provide important information for evaluation of anesthetic depth. We investigated the anesthetic depth as following 7 stages. These are pre-anesthesia, induction, skin incision, before extubation, after extubation, Post-anesthesia. In this study, temporal, frequency and chaos analysis method were used to analyze the HRV time series from electrocardiogram signal. There were NN10-NN50, mean, SDNN and RMS parameter in the temporal method. In the frequency method, there are LF and HF and LF/HF ratio, 1/f noise, alphal and alpha2 of DFA analysis parameter. In the chaos analysis, there are CD, entropy and LPE. Chaos analysis method was valuable to estimate the anesthetic depth compared with temporal and frequency method. Because human body was involved the choastic character.

• IE interfaces
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• v.12 no.1
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• pp.32-42
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• 1999

This paper proposes and implementation procedure for an automatic assembly system from a manual assembly and an evaluation method of implemented several automatic system alternatives using an AHP (Analytic Hierarchy Process) in a small-sized motor. First, the current product is redesigned for DFA (Design For Assembly) and assembly automation of motor, and then it is decided mechanisms of moving, magazining, feeding, composing of each part using main joining equipment and auxiliary equipment. Following the decided mechanism, the necessary assembly machines are selected or designed considering objectives and assembly conditions. Finally, the layout alternatives are completed for the automatic assembly system. According to the evaluation criteria which are established in advance, the automatic system alternatives are analyzed using AHP.

• Korean Journal of Applied Biomechanics
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• v.18 no.2
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• pp.49-58
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• 2008

The purpose of this study was to identify effects of walking speed and a cognitive task during treadmill walking on gait variability. Experiments consisted of 5 different walking speeds(80%, 90%, 100%, 110% and 120% of preferred walking speed) with/without a cognitive task. 3D motion analysis system was used to measure subject's kinematic data. Temporal/spatial variables were selected for this study; stride time, stance time, swing time, step time, double support time, stride length, step length and step width. Two parameters were used to compare stride-to-stride variability with/without cognitive task. One is the coefficient of variance which is used to describe the amount of variability. The other is the detrended fluctuation analysis which is used to infer self-similarity from fluctuation of aspects. Results showed that cognitive task may influence stride-to-stride variability during treadmill walking. Further study is necessary to clarify this result.