• Journal of Internet Computing and Services
• /
• v.21 no.1
• /
• pp.231-236
• /
• 2020

This paper addresses the analysis method about optimal performance and required quantity for Mission-Based drones. In the case of drones, although scientific verification of operational performance and quantity of demanded, such as total flight time, total operation time, and appropriate required quantity, is required depending on the operation concept, there is no methodology for analyzing them systematically. That is the reason this research was carried out. Through the suggestion and study about Mission-Based six step analysis method and, this study can present the optimal ROC (Required Operational Capability) and the required quantity based on the operational concept of drones, and technical and economic effects were suggested.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2015.05a
• /
• pp.105-106
• /
• 2015

As the Long-life certification system is recently introduced in the Housing Law in Korea, it is expected that an application of the lightweight wall panel will be increased in apartment construction as the main wall system. However, the performance criteria for lightweight wall is in the early phase of its action. Therefore, it is necessary to establish the performance criteria properly by investigating performance requirement in the user's perspective. The purpose of this study is to identify of the weight of the required performance items for the lightweight wall in apartment house. To analyze the priority in the performance, an interview survey is performed; after monitering the test-bed of the lightweight walls, user and experts evaluate the performance requirements. The weight of the performance requirement is developed by AHP method.

• International conference on construction engineering and project management
• /
• 2009.05a
• /
• pp.1528-1533
• /
• 2009

Infrastructure is provided to the user through long-term project period and large-scale working expenses. Existing facilities are getting old as time goes by. Accordingly, proper maintenance is required and generally more maintenance cost than initial invested cost is needed during life cycle. Therefore, a specific plan that just increases the value of facilities is required by evaluating performance of facilities and inputting minimum maintenance cost. Value engineering that increases the value of object by systemically analyzing Life Cycle Costs and function is actively promoted at the design phase of construction. These efforts can increase the performance of facilities at the maintenance phase of infrastructure. This study is to search how to evaluate the performance of Roadway by utilizing function analysis, as a core part of VE in the maintenance phase. In order to this a new evaluation criteria were proposed by adding an evaluation items to the existing criteria through the research of old documents, status of roadway maintenance and function analysis of VE. The results of this study may promote the effective performance evaluation to determine a resolution of roadway congestion in future. A succeeding study using the proposed evaluation criteria will be required.

• Proceedings of the Korea Society for Industrial Systems Conference
• /
• 2003.05a
• /
• pp.3-7
• /
• 2003

For high performance Grid environments, an efficient GIS(Grid Information Service is required In the Metacomputing Directory Service(MDS) of the Glogus middleware, the Lightweight Directory Access Protocol(LDAP), which is a distributed directory service protocol, is used. The LDAP GIS differs from general purpose LDAP directories in that most of the LDAP operations are write in Grid environments. To get an efficient design of the GIS, it is thus required to analyze the performance of the LDAP system in the context of Grid environments. This paper presents the result of a performance analysis of LDAP systems. The main objective of the evaluation is to see the performance scalability of the LDAP system in the Grid environment where the write operations prevails. Based on these results, we suggest directions of an efficient LDAP-based GIS for a high performance Grid.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.22 no.1
• /
• pp.1-11
• /
• 1997

We examine the DS/SSMA system which is employing coherent BPSK with RAKE receiver. We adop Nakagami m-distribution as a multipath fading model. First, we analyze the performances of the system in the single cell environment and obtain the other-cell interference according to power control error. And considering the other-cell interference into the analysis of single cell system, we examine the cellular CDMA network. The average BER and outage probability are the figures of merit that characterize the system performance. The required BER, 1E-3, and required outage probability are the figures of merit that characterize the system performance. The requeired BER, 1E-3, and required outage probability, 1% for the voice transmission is considered to acquire the capacity of system.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
• /
• v.11 no.4
• /
• pp.6-18
• /
• 1982

The performance of two typical types of solar hot water heating system was tested in Seoul. Types of systems studied are single-tank internal external heat exchanger system and single-tank internal heat exchanger system. Comparing to experimental results, a transient system simulation program was made to analyze the performance of the selected system. The climate data, Standard Weather Year for Seoul, required for the simulation was provided. Computer simulations were used to estimate the effect of significant parameters upon system performance. The followings are obtained. 1. In the domestic solar water Heating system, the value $20-40kg/m^2\;h$ for flow rate through the collector is much better than the recommended value $72kg/m^2\;h$ in the solar heating system. 2. The effectiveness of collector heat exchanger and storage tank size are found to have only a small effect upon system performance. 3. The hot water draw pattern has a significant effect on system performance. A higher system efficiency achieved when draw-off occurred around noon than when it occurred around early morning. Using the above results, the reference solar hot water system which provides $300\ell$ of hot water per day, was selected as a guide for designer. And simplified graphical method was developed based on the modified f-chart method to determine required collector area. When the system design parameters of the proposed system differs from the reference system, required collector area can be calculated from area adjustment factors.

• Journal of Positioning, Navigation, and Timing
• /
• v.11 no.4
• /
• pp.341-349
• /
• 2022

When designing a new RNSS signal, the performance analysis for the legacy signal providing the same service, is required to determine the performance requirements. However, there are few studies on the secured service (SS) signal performance analysis, and the waveform is the only published information on the signal design component of the SS signal. Therefore, in this paper, we introduce several figures-of-merit (FoMs) that can be used for performance analysis in terms of the waveform. And then, we calculate the FoMs, such as autocorrelation main peak to secondary peak ratio (AMSR), spectral efficiency, Gabor bandwidth, multipath error, and jamming resistance quality factor, for the existing SS signals and discuss the analysis results. Finally, we conclude that the superior waveform for each FoM is different, and that the consideration of the trade-off relationship between the FoMs is required for waveform design.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.29 no.3
• /
• pp.7-15
• /
• 2023

Purpose: This study was conducted with the aim of presenting spatial planning directions for evacuation spaces based on an analysis of the performance of horizontal evacuation during the early stages of fire incidents in a geriatric hospital. Methods: Based on a review of previous studies, the research model was designed by establishing occupancy conditions, evacuation, and fire scenarios. The analysis model was developed by considering vulnerable areas in terms of evacuation movement and analyzing the results of evacuation performance. Furthermore, the study analyzed the improvement in evacuation performance by arranging refuge areas. Results: The results of the study are as follows. Firstly, vulnerability spots were identified in terms of evacuation performance by schematizing Required Safe Egress Time, Available Safe Egress Time, and their differences. Secondly, the Required Safe Egress Time in the adjacent public spaces along the escape routes of occupants was found to be higher compared to the Available Safe Egress Time. Thirdly, the results of the correlation analysis between the difference in Available Safe Egress Time and Required Safe Egress Time during the early stages of a fire, as well as their constituent factors, demonstrated that user congestion is a more significant factor in compromising evacuation safety than the physical changes in the fire condition. Fourthly, the analysis of evacuation time was conducted by designating refuge areas where occupants can evacuate within a sufficient timeframe. This led to a decrease in the Required Safe Egress Time. Implications: This study is expected to be used as data on the direction of evacuation space planning to improve the evacuation performance of Geriatric Hospital.

• Journal of the Korean Society for Precision Engineering
• /
• v.21 no.2
• /
• pp.92-99
• /
• 2004

The errors can cause the serious loss of the performance of a precision machine system. In this paper, we proposed the method of allocating the alignment tolerances of the parts and applied this method to get the optimal tolerances of a Confocal Scanning Microscope. In general, tight tolerances are required to maintain the performance of a system, but a high cost of manufacturing and assembling is required to preserve the tight tolerances. The purpose of allocating the optimal tolerances is minimizing the cost while keeping the high performance of the system. In the optimal problem, we maximized the tolerances while maintaining the performance requirements. The Monte Carlo Method, a statistical simulation method, is used in tolerance analysis. Alignment tolerances of optical components of the confocal scanning microscope are optimized to minimize the cost and to maintain the observation performance of the microscope. We can also apply this method to the other precision machine system.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.14 no.3
• /
• pp.241-245
• /
• 2001

In this paper, we present parameter optimization technique for GaAs/AlGaAs multiple quantum well avalanche photodiodes used for image capture mechanism in high-definition system. Even under flawless environment in semiconductor manufacturing process, random variation in process parameters can bring the fluctuation to device performance. The precise modeling for this variation is thus required for accurate prediction of device performance. The precise modeling for this variation is thus required for accurate prediction of device performance. This paper will first use experimental design and neural networks to model the nonlinear relationship between device process parameters and device performance parameters. The derived model was then put into genetic algorithms to acquire optimized device process parameters. From the optimized technique, we can predict device performance before high-volume manufacturign, and also increase production efficiency.