• Journal of Information Management
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• v.25 no.1
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• pp.24-46
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• 1994

In this paper I will discuss definitions of hypermedia, multimedia and hypertext. Hypertext is the grouping of relevant information in the form of nodes. These nodes are then connected together through links. In the case of hypertext the nodes contain text or graphics. Multimedia is the combining of different media types for example sound, animation, text, graphics and video for the presentation of information by making use of computers. Hypermedia can be viewed as an extension of hypertext and multimedia. It is based on the concept of hypertext that uses nodes and links in the structuring of information in the system. In this case the nodes consist of an the different data types that are mentioned in the multimedia definition above. The 'node-and-link' concept is used in organisation of the information in hypermedia systems. The 'book' metaphor is an example of the way these systems are implemented. This concept is explained and a few advantages and disadvantages of making use of hypermedia systems are discussed. A new approach for the development of hypermedia systems, namely the knowledge-based approach is now looked into. Joel Peing-Ling Loo proposed this approach because he thought that it is the most effective way for handling this kind of technology. A semantic-based hypermedia model is developed in this approach to formulate solutions for the restrictions in presenting information authoring, maintenance and retrieval. The knowledge-based presentation of information includes the use of conventional data structures. These data structures make use of frames(objects), slots and the inheritance theory that is also used in expert systems. Relations develop between the different objects as these objects are included in the database. Relations can also exist between frames by means of attributes that belong to the frames.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.701-711
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• 2000

To provide the baseline information for establishing community based nutritional service system in the context of health promotion, we conducted nutrition survey for 196 adults (male ; 99, female ; 97) in Kyungpook area. Individual food intake was measured by 24-hour recall method, and then diet quality was evaluated by Index of Nutritional Quality (INQ) and Mean Adequacy Ratio (MAR). Average dietary intake of Ca and Vit A of total subjects were lower than Korean Recommended Dietary Allowances (Ca; 83% of RDA, Vit A; 77% of RDA). On the whole, mean nutrients intake of male subjects were higher than that of female subjects. It also appeared that overall nutrients intake of younger women (20~29 yr) were lower than that of other age group. When we evaluated the nutrients intake of the subjects by INQ, Vit C (=2.39) showed the highest score. Ca (=0.89) and Vit A (=0.84) were revealed to be concerned nutrients in both quantity and quality. There was almost no difference in MAR between men and women (Men ; 0.88, Women ; 0.86). MAR showed significantrly positive correlation with age (p<0.05), meal frequency (p<0.001) and negative correlation with education level (p<0.01) in women, whereas no statistically significant relationship among these variables was observed in men. Age and meal frequency showed significantly positive correlation with most nutrients intakes among women. In conclusion, nutrition education strategies for sound food choice and regular meals need to be developed to improve the nutritional adequacy of female adults in the 20's.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.5
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• pp.535-543
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• 2004

Purpose: The purpose of this study is to compare the effect of two fiber post systems and one metal cast post system on the fracture strength and fracture pattern of crowned, endodontically treated teeth with 2 mm-height of the reamining tooth structure. Materials and methods: A total of 36 recently extracted sound human mandibular premolars were selected Each tooth structure of the crown portion except 2mm-height of the one above the cementoenamel junction was removed. After being endodontically treated, they were randomly distributed into 3 groups: group 1, restored with quarts fiber post(D.T. Light-Post), group 2, with glass fiber post(FRC Postec), and group 3, metal cast post and core. All teeth were fully covered with nonprecious metal crowns. Each specimen was embedded in an acrylic resin block and then secured in a universal load-testing machine. A compressive load was applied at a 130 degree angle to the long axis of the tooth until fractured, at a crosshead speed 20mm/min. The highest fracture loads were measured and recorded as the fracture strength of each specimen. Fracture areas were measured on the mid-buccal and mid-lingual point from the crown margins. One-way analysis of variance and Turkey test were used to determine the statistic significance of the different fracture loads and areas among the groups (p<0.05). Results: The mean fracture loads were $1391{\pm}$425N(group 1), $1458{\pm}476N$(group 2) and $1301{\pm}319N$(group 3). The fracture loads among the three groups had no statistically signifiant difference (p>.05). The mean fracture area of the fiber post was closer to the crown margin than that of the metal cast post and core(p<.05). The metal cast post showed unrestorable and catastrophic fracture patterns. Conclusion: Within the limitations of this study, fracture loads with any statistically significant difference were not recorded for endodontically treated teeth restored with two fiber posts and the metal cast post. But teeth restored with the fiber posts typically showed the fracture pattern close to the crown margin, which was almost restorable.

• Fire Science and Engineering
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• v.30 no.4
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• pp.1-5
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• 2016

This research performed tests of Video Fire Detector and criteria of installation to make suggestions regarding the criteria that must be reflected in NFSC 203 by comparing the standards of FM Approvals, UL, ISO7240 and NFPA 72. FM Standard related to Video Fire Detector test has been classified as Smoke, Flame type, but the UL Standard has classified only as a Smoke type. This research examined 6 cases of fire phenomenon detection case in ISO 7240 and 3 cases in NFPA 72, respectively. There are 15 items required for the installation standard of a Video Fire Detector and each field standard is presented as a per installation method. To apply a Video Fire Detector, the pertinent items (the definition of term, detector's classification, structure and function among its test item) must be inserted. In addition, 7 items of the fire test, i.e., the sensitivity adjustment, prevent false alarm, ambient temperature test, the effective sensitivity and detection distance and viewing angle, aging test, flood test, must be applied to the actual test. For installation in the field, the operation environment and levels of illumination, and NFSC 203 must be set, and standards relevant to the sound system, indicators' installation distance, etc. need to be inserted.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.43-49
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• 1973

In this study noise source in a ward at four general hospitals in Seoul area has been investigated and analysed. The degree of reaction against noise by 171 randomly has also been examined. The results of the study have shown that the source of noise is the speakers of wired broadcasting or from visiting guests in two hospitals located in residential area. The patients at the two other hospitals located at commercial site have been suffered more from traffic noise. However, because of their separated living at hospital from their ordinary houselife, sixty one percent of the inpatients have wished a music sound of around 60 dB (A). After having considered the results of the investigation and wishes of the inpatients, following suggestions have been made: 1. Reduce the number of guests or their length of stay. 2. Wired broadcasting system should be substitued by wireless one, or if it's unavoidable, it should be used in office rooms only. 3. Since the stops and starts of vehicles induce much noise, Seoul City Government be requested to prepare an appropriate administrative measure for the vehicles around hospital area and it should prevent the establishment of new hospitals along high way site. 4. By using earphone, inpatients can choose a wireless channel according to each individual's taste. This through the masking effect, would cover up the noise source. 5. Rooms along the streets should be utilized as offices, otherwise double windows should be set up for inpatient's wards.

• International Journal of Highway Engineering
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• v.10 no.3
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• pp.57-68
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• 2008

The stabilization techniques in the pavement foundations have advantages in increasing pavement performance and reducing pavement thickness. By mixing the geomaterials and stabilizer, the economical and structurally sound layer can be added in the pavement system. Until now, these techniques have been applied in the field empirically and the design criteria for stabilization has not been established. The purposes of this paper are to evaluate the mechanistic properties of stabilizers used for geomaterials and determine the type and optimum amount of stabilizer for each technique. The unconfined compressive testing and repeated load resilient modulus test were conducted on the coarse grained soils mixed with various types of stabilizer to investigate the strength and deformation characteristics of stabilized geomaterials. It is found from the test that the unconfined compressive strength of stabilized geomaterials is more than ten times higher than that of gradation modified geomaterials. The resilient modulus of stabilized geomaterials increases by $6{\times}10$ times compared to the original soils and tends to increase with increase of volumetric and deviatoric stress, and amount of stabilizer.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.4
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• pp.604-610
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• 2005

This study was to evaluate the effects of several light curing units on the microleakage of composite resin restorations in primary teeth. The types of curing units were traditional low intensity halogen light(Optilux 360), plasma arc light(Filpo) low heat plasma arc light(Aurys) and high intensity LED(Freelight 2). After preparing cavities on sound primary teeth, cavities were filled with composite resin(Z100) using the same resin bond agent(Scotchbond Multi-Purpose) and were cured with each curing light system. After storing each specimen in sterile water for 24 hours, thermal circulation was done 1,000 times followed by pigmentation using 2% methylene blue solution. Each specimen was sliced and the degree of pigmentation was graded. When microleakage is graded, the average of Aurys was 0.95 which was the lowest and Freelight 2(1.05), Filpo(1.25), Optilux 360(1.30) followed. But values were not shown statistically significant difference (P>0.05). The results suggest that the newly developed curing units which has advantage in children by decreasing discomfort and procedure time can increase the microleakage of the composite resin.

• Journal of the Institute of Convergence Signal Processing
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• v.20 no.4
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• pp.245-251
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• 2019

Sonar bearing accuracy is the correspondence between the target orientation predicted by sonar and actual target orientation, and is obtained from measurements. However, when measuring sonar bearing accuracy, many errors are included in the results because they are made at sea, where complex and diverse environmental factors are applied. In particular, parallax error caused by the difference between the position of the GPS receiver and the sonar sensor, and the time delay error generated between the speed of underwater sound waves and the speed of electromagnetic waves in the air have a great influence on the accuracy. Correcting these parallax errors and time delay errors without an automated tool is a laborious task. Therefore, in this study, we propose a sonar bearing accuracy measurement equipment with parallax error and time delay error correction. The tests were carried out through simulation data and real data. As a result of the test it was confirmed that the parallax error and time delay error were systematically corrected so that 51.7% for simulation data and more than 18.5% for real data. The proposed method is expected to improve the efficiency and accuracy of sonar system detection performance verification in the future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.6
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• pp.751-758
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• 2015

Noise prediction for HVAC(Heating, Ventilating and Air Conditioning) systems are normally performed by empirical method suggested by NEBB(National Environmental Balancing Bureau, 1994). However, the method is not suitable for large ducts in ships. In this paper, computational analysis methods are used to develop a noise prediction method for the large ducts in ships. To develop regression formula of attenuation of sound pressure level in large ducts, Boundary Element Method(BEM) is used. BEM and Computational Fluid Dynamics(CFD) are applied to the analysis of flow-induced noise in ducts with stiffeners inside. Loud noise above 100 dB can be generated in some cases. Breakout noises of large ducts are also analyzed by using BEM and Finite Element Method(FEM). The acoustic pressure level shows about 10-15dB difference between inside and outside of the duct. Utilizing the results of this study, it is expected that shipyard planners can predict noise of the HVAC system for ships.

• Journal of Cadastre & Land InformatiX
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• v.45 no.1
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• pp.75-97
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• 2015

Recently public institutions' debt is growing therefore it became an important issue to the level that the government concerns about the possibility of financial burden to reduce the debt. Especially debt of public enterprises in metropolitan areas was in a serious state where debt in late 2013 was 43.2 trillion, which takes approx. 58.4% of 73.9 trillion of debt of all local public enterprises. Sound financial state of local public enterprises is important to public enterprises in metropolitan areas and it may affect seriously financial stability of local governments when public enterprises have financial problems. However, land supply business to form local industrial complexes or local demand for development of public rental housing business always exist; and vitalizing local economy and creating jobs through these businesses are very necessary to develop the areas. However, for local economic development, industirial land business and public rental housing business are needed. In this study, Gwangju Metropolitan City Corporation Ltd is used as a case study to evaluate the local public financial soundness via debt management assessment i.e.(using) the feasibility analysis in the urban development and housing development. As an improvement measure following the result of analysis, for the enhancement of financial soundness of urban innovation corporation, the government and local government shall evaluate and differentiate market demand, price competitiveness, and infrastructure of new town land development project to improve accuracy of project feasibility analysis. Another important insight is that there should be local government-centered management of liabilities of the local government and local public enterprises with the integrated liability management system to reduce the liability of the corporation and solve the issue of debts for local government. This study is significant in that it has analyzed cases from the theoretical aspect to secure financial soundness of national and local public enterprises.