• Journal of KIISE:Software and Applications
• /
• v.31 no.10
• /
• pp.1364-1373
• /
• 2004

Recently Evolvable Hardware (EHW) is widely studied to design effective hardware circuits that can reconfigure themselves according to the environment. However, it is still difficult to apply for complicated circuits because the search space increases exponentially as the complexity of hardware increases. To remedy this problem, this paper proposes a method to evolve complex hardware with a modular approach. The comparative experiments of some digital circuits with the conventional evolutionary approach indicate that the proposed method yields from 50 times to 1,000 times faster evolution and more optimized hardware.

• Geophysics and Geophysical Exploration
• /
• v.16 no.1
• /
• pp.59-62
• /
• 2013

We formerly reported a new method for the upward continuation of potential field on spherical patch area including Earth's curvature, which has been neglected in most studies on rectangular area with flat Earth assumption. This new method is applicable to downward continuation as well by only assigning corresponding value for the ratio of two radii; $r_2/r_1$, i.e., target radius $r_2$ versus datum radius $r_1$. In addition, the inherent problem of this method due to spherical surface geometry is described, and its one possible remedy is given.

• International Journal of Control, Automation, and Systems
• /
• v.6 no.1
• /
• pp.86-100
• /
• 2008

Most of the previously employed dynamic modeling approaches, including Natural Orthogonal Complement Algorithm, have limitations on their application to the mobile robot, specifically at singular configurations. Also, in their dynamic modeling of mobile robots, wheel dynamics is usually ignored assuming that its dynamic effect is negligibly small. As a remedy for this, a singularity-free operational space dynamic modeling approach based on Lagrange's form of the D' Alembert principle is proposed, and the singularity-free characteristic of the proposed dynamic modeling is discussed in the process of analytical derivation of the proposed dynamic model. Then an accurate dynamic model taking into account the wheel dynamics of the omni-directional mobile robot is derived, and through simulation it is manifested that the effect of the wheel dynamics on the whole dynamic model of the mobile robot may not be negligible, but rather in some cases it is significantly large, possibly affecting the operational performances of dynamic model-based control algorithms. Lastly, the importance of its accurate dynamic model is further illustrated through impulse analysis and its simulation for the mobile robot.

• The Korean Journal of Air & Space Law and Policy
• /
• v.5
• /
• pp.119-169
• /
• 1993

In this article the present writers have surveyed recent cases on Warsaw Convention especially on the cases emerged in the years between 1986 to 1993. The cases before 1986 were discussed already in the book titled "Liability of International Air Carrier," written by Professor Choi, published in Seoul 1986. In this article the writers have reviewed most of the American cases and some cases from the courts of Germany, France and England. Main subjects which were discussed herein were as follows: Liability of air carriers in Warsaw Convention carriage 1. Exclusivity of the Warsaw Convention as a remedy 2. Warsaw Jurisdiction 3. The scope of the Warsaw Convention's definition of "Accident" under Article 17 of the Warsaw Convention (1) Mental anguish (2) Unusual or unexpected events 4. Adequacy of notice of the limitation of liability to passengers for injuries and death 5. Damages recoverable, punitive damages and burden of proof 6. The wilful misconduct exception; definition of wilful misconduct 7. Cargo and passenger baggage 8. Time limitation of actions After examining articles published world-wide, this article compiles and analyses recent cases involving the Warsaw Convention system. As Warsaw System is based on international convention, maintaining uniformity in interpretation is of utmost importance. Therefore, this type of study is essential for resolving air-transportation disputes in Korea. This article examines the current state and recommends the desired course for the Warsaw Convention. The writers hope that this article is helpful to the Korean courts and those in the air-transportation industry in interpreting the Warsaw Convention.

• The Journal of the Korea Contents Association
• /
• v.13 no.3
• /
• pp.141-151
• /
• 2013

With the spread of Personal Computers(PC) in the 1980's, many people started to deal businesses with PC. From late 1990's, the Internet age with PC have started and many people have showed keen interest in cyber-space and now they are utilizing it. Since 2000's the use of cyber-space have skyrocketed and it caused significant changes to humans' life. There was a huge prosperity to us but the new kind of crime, cyber-crime, was raised. Unlike past physical type of crimes, those cyber-crimes take place in the cyber-space and they have special features of non-facing, anonymity, specialty, technologic, repetition, continuation. Those cyber-crimes are continually growing since 2003 and in 2010 it almost doubled compared to 2003. General cyber-crimes like phishing-scam pornography circulation was most of them and notably perpetrators of them are younger generation. Recently cyber-crimes are showing the trend of advancing more and more and cyber-bullying, fraud like phishing scam are on the rise. The police are responding by making 'Cyber Terror Response Center', but it does not work effectively with the problems of breakup of prevention and investigation unit, procedure of investigation and the system itself. So, I suggest practical use of private security to remedy our police's weakness and to prevent cyber-crimes. Preventing solutions of cyber-crime with private security are physical defense of large-scale servers and vital computers, building of Back-up system to prevent vital data loss, and building of cyber-crime preventing system combining software and hardware.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.15 no.6
• /
• pp.2026-2036
• /
• 1991

An expert system is developed which can diagnose the causes and remedies of the failures of power transmission gears. The basic components of the expert system are knowledge base, inference engine, and working memory. The knowledges in knowledge base are classified into the knowledges for determining the failure types and for diagnosis of causes and remedies of the failures. The former is represented hierarchically into the main category of eleven groups by rules and the sub category of twenty four groups by facts, while the later is represented by facts according to the each group of knowledges. In the inference engine some considerations are implemented, i.e., the backward chaining method and depth first search to determine the category of the failures, the meta-knowledges to shorten the search space, the certainty factor to evaluate the reliability of result, and the unification strategy to diagnose the causes and remedies of the failures. The working memory is established to hold the results during inference temporarily. In addition, knowledge acquisition facility, explanation facility, and user interface are included for the usefulness of user. This expert system is written with the PROLOG programming language on IBM-PC compatible computer operated by MS-DOS and be executed alone.

• Journal of Soil and Groundwater Environment
• /
• v.25 no.3
• /
• pp.43-51
• /
• 2020

About 90% of groundwater wells in Jeju Island are reported to be under the threat of contamination by infiltration of the surface pollutants. Most of those wells have improperly grouted annulus which is an empty space between the well and the inner casing. As a remedy to this problem, some of the wells were re-grouted by filling the annulus with cement without lifting an inner casing. In order to evaluate whether this method is appropriate for the geological structure of Jeju Island, two wells (W1 and W2) were selected and this method was applied. The water holding capacity did not decrease while the nitrate levels decreased from 16.8 and 20.2 to 6.8 and 13.8 mg/L in W1 and W2, respectively. The higher nitrate level in W2 is deemed to be influenced by the livestock farms located in the upper area of the well. In addition, transmissivity of the vedose zone was higher in W2 than W1, potentially facilitating the transport of nitrate to the groundwater. The overall result of this study suggests re-grouting of wells for the purpose of protecting water quality of goundwater should take into account geological structure of vadose zone as well as appropriate source control of the contaminants.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.24 no.4
• /
• pp.282-288
• /
• 2014

Three-dimensional multimedia industry such as 3D TV, movie and broadcast has been developed vividly. For generating 3D contents with high quality, virtual auditory display, so called VAD, is being researched to offer more realistic experience to listeners. When people render VAD using headphones or two speakers, head-related transfer function(HRTF) plays a key role. The best solution is measuring all individuals' HRTFs, but it is hard to measure all listeners' HRTFs. To overcome this difficulty, many research groups have tried to construct their own measurement system and to build HRTF databases. However, some of them have not enough subjects or spatial resolution and they are mainly focused on Caucasian. There exists difference between Korean and Caucasian in a view of physical features. In other words, if Koreans hear three-dimensional sound rendered by HRTF database based on Caucasian, performance might be hindered. To verify this possibility and remedy the drawbacks, construction of new HRTF database aimed at Korean is needed. Therefore, our laboratory built HRTF measurement system which can measure HRTF of three-dimensional space with dense spatial resolution. With this system, 55 Korean males and 45 females' HRTFs were measured and Korean HRTF database was built based on these data.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.30 no.6
• /
• pp.98-108
• /
• 2003

The research purpose of this study, together with the study of Frank Stella's work and his expansion of the formative arts field, is to rediscover "Amabel" and to present a fresh perspective in evaluating and assessing environmental art objects. The results of this study can be summarized as follows. 1. The study investigated the effect how Frank Stella's work affected American modem art trends. 2. The study helped to re-evaluate Stella's work by examining its expansion into the plastic arts. 3. The study analysed the plastic works of Prank Stella and his effect on plastic arts within the modem art trend of America. In conclusion, Frank Stella played a leading role in today's American art style and had a potent influence on the trends of America's modem U. In recent years, his work has had an impacted on the design of parks and art galleries. America's industrial society is led by the growth of economic power and the development of science and technology. In America's architecture and landscape architecture, such new forms as minimalism functionalism, cubism and abstract expressionism, which have been influenced by art movements, emerged in California and the east coast. Influences of Stella such as these are the remedy for a vested stubborn concept of architecture and landscape architecture by introducing a sense of pictorial space in these fields. In landscape architecture, the introduction of art trends appears in several ways. Mainly the trend of Minimalist Art, influenced by Modernism, can be seen in much Landscape Architecture. Frank Stella contributed to the development of such minimalist art.

• Journal of KIISE:Computing Practices and Letters
• /
• v.16 no.6
• /
• pp.648-653
• /
• 2010

The non-metric multidimensional scaling (nMDS) is a method for analyzing the relation among objects by mapping them onto the Euclidean space. The nMDS is useful when it is difficult to use the concept of distance between pairs of objects due to non-metric dissimilarities between objects. The nMDS can be regarded as an optimization problem in which there are many local optima. Since the conventional nMDS algorithm utilizes the steepest descent method, it has a drawback in that the method can hardly find a better solution once it falls into a local optimum. To remedy this problem, in this paper, we applied the simulated annealing to the nMDS and proposed a new optimization algorithm which could search for a global optimum more effectively. We examined the algorithm using benchmarking problems and found that improvement rate of the proposed algorithm against the conventional algorithm ranged from 0.7% to 3.2%. In addition, the statistical hypothesis test also showed that the proposed algorithm outperformed the conventional one.