• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.5
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• pp.1011-1019
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• 2015

CAPTCHA(Completely Automated Public Turing test to tell Computers and Humans Apart) is a test used in computing to distinguish whether or not the user is computer or human. Many web sites mostly use the character-based CAPTCHA consisting of digits and characters. Recently, with the development of OCR technology, simple character-based CAPTCHA are broken quite easily. As an alternative, many web sites add noise to make it harder for recognition. In this paper, we analyzed the most recent CAPTCHA, which incorporates the addition of the natural images to obfuscate the characters. We proposed an efficient method using support vector machine to separate the characters from the background image and use convolutional neural network to recognize each characters. As a result, 368 out of 1000 CAPTCHAs were correctly identified, it was demonstrated that the current CAPTCHA is not safe.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8195-8209
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• 2015

The purpose of this paper is to propose a method for recommendation and personalization of important news articles based on evaluating news value. Evaluation of news is the approach by which editors select news articles for cover-story in traditional offline news papers area. For this, my study proposes a suite of methods to select and personalize a set of news based on evaluating news articles, not just on the personal preference for them. The aforementioned the value of news articles including social impact, novelty, relevance to each audience, and human interest, all of which have been factorized in many previous studies, is a main concept for a procedural and structural application methodology deduced in this study. After a comparative case study with other online news services, it was shown that my research provides more effective way to select important news articles in terms of user satisfaction than others.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.1
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• pp.109-115
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• 2010

This paper deals with trajectory control of computer simulated mobile robot via fuzzy control. Mobile robot is controlled by Mamdani type fuzzy controller. Inputs of the fuzzy controller are angle between mobil robot and target, changed angle and output is the steering angle, which is control input. Fuzzy rules have seven rules and are selected by human experiential knowledge. Also we propose a scaling factors tuning scheme which is the another focus in designing fuzzy controller. In this paper, we adapt the RCGA which is well known in parameter optimization to adjust scaling factors. The simulation results show that the fuzzy control effectively realize trajectory stabilization of the mobile robot along a given reference target from various initial steering angles.

• Archives of design research
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• v.20 no.3 s.71
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• pp.345-354
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• 2007

Sometimes characterized graphic map rather than realistic graphic map can help users to understand information more easily. This paper tried to reveal the relation between the methodology to create outline on the map using caricature automatic algorism and level of human cognition. Caricature algorism such as exaggeration transformation algorism, joint transformation algorism and simplification algorism were used to create outline on the map. In order to apply exaggeration transformation algorism and joint transformation algorism, the method to create average form of the object were developed. We survey how users recognize the similarity of the characterized map with the real map when realistic map is simplified by certain value of simplification rate and transformed into certain value of exaggeration rate or joint transformation rate. We also survey how users recognize the similarity differently according to the scale of the map. As a result of this study, the method to calculate the optimal data is developed for users to recognize caricatured map effectively by shifting scale. This data can be used as basic data, when map developers create outline of map with programming code on computer

• Journal of Korean Library and Information Science Society
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• v.12
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• pp.35-59
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• 1985

User fees have been employed by libraries as far back as the mid-1800s in both United States and England. By the late 1800s and early : 1900s, the charging of user fees for some library products and services had become a reality in many public and academic libraries. Yet the practice has created controversy when computer-aided reference service began to charge especially in the publicly funded libraries. There are two extream arguments on library reference service fees : one is for and the other is against. most fee o n.0, pponents base their stand on morality. They argue that charging fees for any service is wrong because it violates the user's right of access to information and regard it as an act of decrease human life chances as well as an act of censor. But those who favour fees argue that it is necessary to separate the rhetoric from the reality and to distinguish what libraries are from what they do. The study revealed that library has two options. One is strict free of charge and the other is charging for selected library services. Whatever options the library may take, library had to decide an overall reference service policy. The level and scope of service, audience, necessary fund (who and how) and many other physical and metaphysical things must be considered. However, the first option will necessary be to limit services while there is no loss of traditional philosophical service element. Yet, if to provide a wide range of choices and to create conditions more hospitable to competition from the private information sector and for better evolutional selection, the second option(fee-based service) gives more benefit to the users while there is a loss of fundamental service philosophy.

• Journal of Preventive Medicine and Public Health
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• v.32 no.3
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• pp.374-382
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• 1999

Objectives: Organizational culture has beer important in field of organizational behavior research for the past decade. Although there has been a growing interest in the organizational culture and organizational effectiveness, there is few research in health care field. This study was carried out to investigate the relationship of organizational culture and organizational effectiveness at general hospital. Methods: Data was collected by self-administrated questionares. Organizational cultures were measured by using Likert scale. A general hospital in Kyunggi-Do was selected and survey was conducted to 675 workers. Data was analyzed with computer package, PC-SPSS. Results: There were four types of organizational culture in this hospital consensual culture, developmental culture, hierarchical culture, rational culture. Many workers recognized their culture as rational culture and developmental culture. This finding showed that the hospital had both human related and task related climate. There were some differences in recognition of sub-organizational culture by occupational group, but perceived organizational culture was in accordance with sub-organizational culture in general. Multiple regression analysis and multiple logistic regression analysis were conducted to find the relationship of organizational culture and organizational effectiveness. As a result, developmental culture showed a strong relationship with organizational commitment and job-satisfaction. Conclusions: These results showed that types of organizational culture were significantly related to organizational effectiveness and understanding the existing culture is essential to develope their organizational effectiveness.

• Archives of design research
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• v.18 no.4 s.62
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• pp.45-52
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• 2005

Displays, playing an essential role in HCI, have been developed to deliver more vivid and live pictures. LCD and PDP have the most common usage among various displays to present the dynamic textual information in restricted and open places. Important and unsolicited information is being provided by hundreds of displays while we don't even perceive the information. Watching context, effective color combinations of the text and background, speeds of presentation, contexts, and types of display for leading method, moving words cross the display from right to left, were investigated with readability, comprehensibility, and overall satisfaction were compared. LCD peformed better than PDP on all comparisons u4th typical text (black, white) and background (white, black) color better than other color combinations. Normal and fast text presentation was believed more preferred when only textual information was given while slower presentation was evaluated more efficient if multimedia contents were presented with textual information.

• Archives of design research
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• v.19 no.1 s.63
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• pp.59-68
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• 2006

Scarf has played an important role not only as keeping warm of human body but also as accessory of clothes. These days with taking a growing interest of accessory, scarf had thrown off a subsidiary part and gradually had a leading place which guides the overall mode of fashion. Because scarf design of Korea does not get out of imitation step of foreign countries brands it is necessary to develop the scarf design which can show the cultural identity and originality of Korea in international society. Therefore in this study, I chose lotus flower patterns expressed on Buncheon pottery and Korean traditional patchwork cloth as the subject material of scarves design development, and my intention for this study is to develop scarves designs of Korean images by adding modern scenes. For that, first I researched lotus flower patterns expressed on Buncheon pottery and Korean traditional patchwork cloth. Among those materials, I selected to had been presented modern image. And by using computer design program of adobe illustrator 10.0 I designed the basic patterns of three types and developed the square scarves design and rectangle scarves design with those.

• Journal of Biomedical Engineering Research
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• v.28 no.6
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• pp.811-816
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• 2007

The social activities of the elderly have been increasing as our society progresses toward an aging society. As their activities are increased, the occurrence of falls that could lead to fractures are increased. Falls are serious health hazards to the elderly and we need more thorough understanding of falls including the progress of falls and the impact area in various fall directions. Many of the traditional methods of falls research dealt with voluntary falls by younger subject since older subject can easily get fracture from voluntary falls. So, it has been difficult to get exact data about falls of the elderly. Here, we tried to capture the characteristics of the movements of major joints using three dimensional motion capture system during falls experiments using a moving mattress that can safely induce unexpected falls. Healthy younger subjects participated in the actual falls experiment and the moving mattress was actuated by a pneumatic system. The kinematic parameters such as velocities and accelerations of major segments were imported to a computer simulation environment and falls to hard surfaces were simulated in a computational environment using a realistic human model of aged persons. The simulation was able to give approximations to contact forces which can occur during actual falls.

• Journal of Korea Game Society
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• v.6 no.2
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• pp.13-22
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• 2006

As the development of games continues, the intelligence of NPC is becoming more and more important. Nowadays, the NPCs of MMORPGS are not only capable of simple actions like moving and attacking players, but also utilizing variety of skills and tactics as human-players do. This study suggests a method that grants characters used in RPG(Role-Playing Game) an ability of training and adaptation using Neural network and Genetic Algorithm. In this study, a simple game-play model is constructed to test how suggested intellect characters could train and adapt themselves to game rules and tactics. In the game-play model, three types of characters(Tanker, Dealer, Healer) are used. Intellect character group constructed by NN and GA, and trained by combats against enemy character group constructed by FSM. As the result of test, the proposed intellect characters group acquire an appropriate combat tactics by themselves according to their abilities and those of enemies, and adapt change of game rule.