• IE interfaces
• /
• v.22 no.1
• /
• pp.95-103
• /
• 2009

During the past few years, design of experiments (DOE) has been gaining acceptance in the telecommunications research community as a mean for designing and analyzing experiments economically and efficiently. In addition, the need for introducing a systematic robust design methodology (i.e., one of the most popular DOE methodologies) to network simulations has been increasing. In this paper, we present an architecture of voice over IP (VoIP) application and the E-Model for calculating the perceived quality of service (QoS). Then, we apply the Taguchi robust design methodology to optimize the perceived QoS of VoIP application, and describe the detailed step-by-step procedures. We have used ns-2 simulator to collect experimental data in which the SN ratio, a robustness measure, is analyzed to determine an optimal design condition. The analysis shows that "initial delay time in playout buffer" is a major control factor for ensuring robust behaviors of the perceived QoS of VoIP. Finally, we verify the proposed optimal design condition using a confirmation experiment.

• Korean Institute of Interior Design Journal
• /
• v.14 no.2 s.49
• /
• pp.83-94
• /
• 2005

20th century was the age of Modernism which was based on rational side of human mind. However, with the fall of Modernism, also came the fall of rationalism's dictatorship. Now, we see the pursuit and quest of irrational thinking as a new possibility of human expression which actually was already begun by Dada and Surrealism in early 20th century. It was facilitated by re-evaluation of Freud's psychoanalytic theory at the end of 20th century. This paper researches psychoanalytic approach applied to the analyses of unconscious human desires in art and design, especially its application to contemporary space design. These designs represent, without making any ethical evaluation, the fact that those unconscious desires are part of inborn human nature and the fact that 21st century is heading toward open society which embraces diverse values and possibilities. By analyzing irrational tendencies in contemporary space designs, this paper aims at proving the meaning and value for one of new directions in 21st century space design. First chapter is an introduction. Second chapter studies Freud's psychoanalytic theory. Third chapter examines the psychoanalytic methodologies with which unconscious desires are expressed in art and design. Fourth chapter classifies the types of subconscious desires expressed in contemporary space designs and analyzes their case studies. Fifth chapter is the conclusion.

• IE interfaces
• /
• v.24 no.3
• /
• pp.210-219
• /
• 2011

The traditional AHP(Analytic Hierarchy Process) is to evaluate subjectively the alternatives in the view point of each of criteria and has been widely used at the fields of real world application. The AHP has some drawbacks that makes it difficult to keep the consistency of decision makers' input and take too long to get accurate results because of requiring lots of pairwise comparison between criteria and alternatives. This research is to propose and develop a Hybrid-AHP system for complementing the critical points of traditional AHP methodologies. This system gets the quantitative information as well as qualitative inputs as the comparative ones between criteria and alternatives. We use the input as various type of information such as quantitative values, 9-scale ratings, and fuzzy-based inputs. Finally, we applied the system to the case of choosing strategic industries. The case study have shown the use of various input methods saves processing time, and reduces the input burden of users.

• Wind and Structures
• /
• v.26 no.6
• /
• pp.383-395
• /
• 2018

An accurate determination of wind speed distribution is the basis for an evaluation of the wind energy potential required to design a wind turbine, so it is important to estimate unknown parameters of wind speed distribution. In this paper, Gumbel distribution is used in modelling wind speed data, and alternative robust estimation methods to estimate its parameters are considered. The methodologies used to obtain the estimators of the parameters are least absolute deviation, weighted least absolute deviation, median/MAD and least median of squares. The performances of the estimators are compared with traditional estimation methods (i.e., maximum likelihood and least squares) according to bias, mean square deviation and total mean square deviation criteria using a Monte-Carlo simulation study for the data with and without outliers. The simulation results show that least median of squares and median/MAD estimators are more efficient than others for data with outliers in many cases. However, median/MAD estimator is not consistent for location parameter of Gumbel distribution in all cases. In real data application, it is firstly demonstrated that Gumbel distribution fits the daily mean wind speed data well and is also better one to model the data than Weibull distribution with respect to the root mean square error and coefficient of determination criteria. Next, the wind data modified by outliers is analysed to show the performance of the proposed estimators by using numerical and graphical methods.

• Journal of Applied Reliability
• /
• v.11 no.4
• /
• pp.433-445
• /
• 2011

Duty cycle is determined as the ratio of operating time to total time. Duty cycle in reliability prediction is one of the significant factors to be considered. In duty cycle application, non-operating time failure rate has been easily ignored even though the failure rate in non-operating period has not been proved to be small enough. Ignorance of non-operating time failure rate can result in over-estimated system reliability calculation. Furthermore, utilization of duty cycle in reliability prediction has not been evaluated in its effectiveness. In order to address these problems, two reliability models, such as MIL-HDBK-217F and RIAC-HDBK-217Plus, were used to analyze non-operating time failure rate. This research has proved that applying duty cycle in 217F model is not reasonable by the quantitative comparison and analysis.

• Journal of the Korean Society of Costume
• /
• v.29
• /
• pp.53-70
• /
• 1996

The inspiration and its application in fashion design is considered as one of the important factors in boosting the fashion arena. Many inspirations are adapted in fashion de-sign and they make the fashion design unique and characteristic. In this study many fashion designs are analyzed to find what kind of inspirations were adapted and utilized for the fashion design in reality. The nature historic costumes ethcin costumes arts sciences literature music sports were revealed as the sources of fashion inspiration.l The concerns on the environments movies and dramas could provide inspirations in fashion as well. Several contents or steps were studied to provide the one of the example of appli-cations as follows: 1. The works of Marc Chagall were analized to figure out and several plastic characteristics from his works were revealed such as fantastic strong colors unreal animal pattern or their details his wife and friends various divisions of the surface and so on. These attributes had been favored in depiction of his works to ex-press his home town or nostalgia. 2. '90s fashion designs inspired by the works of Chagall were analized to find out the meth-odology or the process of designs. The same Chagall colors were used in design and similar pattern were expressed through beaded work or printing jobs. The surface designs such as printing were the most prefered method in adapting the inspirations. 3. The plastic characteristics of the work of Chagall were attempted in clothing design and construction. The color combination patterns which remind the animals the surface divisions were used in design ot practive the methodologies.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.8 no.7
• /
• pp.2512-2531
• /
• 2014

We propose a new Distributed Denial of Service (DDoS) defense mechanism that protects http web servers from application-level DDoS attacks based on the two methodologies: whitelist-based admission control and busy period-based attack flow detection. The attack flow detection mechanism detects attach flows based on the symptom or stress at the server, since it is getting more difficult to identify bad flows only based on the incoming traffic patterns. The stress is measured by the time interval during which a given client makes the server busy, referred to as a client-induced server busy period (CSBP). We also need to protect the servers from a sudden surge of attack flows even before the malicious flows are identified by the attack flow detection mechanism. Thus, we use whitelist-based admission control mechanism additionally to control the load on the servers. We evaluate the performance of the proposed scheme via simulation and experiment. The simulation results show that our defense system can mitigate DDoS attacks effectively even under a large number of attack flows, on the order of thousands, and the experiment results show that our defense system deployed on a linux machine is sufficiently lightweight to handle packets arriving at a rate close to the link rate.

• Journal of Korea Multimedia Society
• /
• v.18 no.3
• /
• pp.298-311
• /
• 2015

Vector data represents a map by its coordinate and Raster data represents a map by its pixel. Since these data types have very large data size, data compression procedure is a compulsory process. This paper compare the results from three different methodologies; GIS (Geographic Information System) vector map data compression using DP(Douglas-Peucker) Simplification algorithm, vector data compression based on Bin classification and the combination between two previous methods. The results shows that the combination between the two methods have the best performance among the three tested methods. The proposed method can achieve 4-9% compression ratio while the other methods show a lower performance.

• Journal of Oral Medicine and Pain
• /
• v.24 no.2
• /
• pp.181-187
• /
• 1999

The most important progress in diagnostic sciences is the increased sensitivity and specificity in diagnostic procedures due to the development of newer micromethodologies and increasing availability of immunological and molecular biological reagents. The outcome of researches in this field has already provided DNA probes and antibodies which can be used for diagnosing various kinds of diseases including inherited ones. This development can be also applied to diagnose diseases in oral and maxillofacial regions. Technological advances have yielded highly sensitive test methodologies so that low analyte concentration and small sample volume are no longer limiting factors. Therefore, saliva can be useful test fluid for an array of analytes. Salivary constituents of diagnostic significance include steroid hormones, antibodies, drugs, and tumor markers. Of the proteins present in saliva, viral-specific immunoglobulins are of the greatest diagnostic interest. The development of conjugates and antigens by recombinant DNA technique and peptide synthesis is necessary for clinical application. Several kits developed for the purpose of blood testing should be modified to permit their application to saliva. The final practical outcome of researches in diagnostic sciences will be various diagnostic agents which can be used for detection of bacteria and viruses, screening and diagnosis of diseases, genetic screening for forensic individual identification. For these purposes, collaboration researches and development between institutions and companies are essential.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.10a
• /
• pp.978-981
• /
• 2003

Component-Based Development(CBD) for a system has benefits in terms of improvement of operation and maintenance as well as reduction of development period. But applying the CBD methodology to a system can give rise to difficulties, which are there should be specialists in CBD and domain to apply and there would be a lot of products resulting in the application. To solve the problems, we suggested a suitable methodology in overall process from analysis to implementation after investigating the methodology applicable to small and medium software system by software systems engineering approach. In the application of the suggested methodology to design a ship design process management system, we could confirm the efficiencies of the methodologies.