• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.126-131
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• 2010

Objectives: This study is aimed to determine any differences in the postoperative stability between absorbable and titanium plate systems for fixation in orthognathic surgery with simultaneous maxillomandibular procedures especially including maxillary posterior impaction and advancement. Study Design: Forty patients with dentofacial deformities were randomly assigned into titanium (4 males and 6 females) and absorbable (17 males and 13 females) fixation group. All patients had undergone surgical alterations of maxilla with posterior impaction and advancement. A comparison study of the change in the maxillary position after the simultaneous surgery was performed with 1-day, 6-months postoperative lateral cephalograms compared to preoperative lateral cephalogram by tracing. Wilcoxon rank sum test was used for statistical analysis. Result: The position of the maxilla was stable after surgery and was not changed significantly from 1 day to 6 month after the simultaneous maxillomandibular surgery both in the experimental (absorbable plates) and control (titanium plates). Conclusion: This study suggests that application of absorable plating system in the fixation of maxillary segment in the simultaneous maxillomandibular procedures, leads to a predictable short-term postoperative skeletal stability comparable to the titanium plating system. Long term follow-up and further studies will be needed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.4
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• pp.73-82
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• 1989

Various analytical procedures for the structural behavior of concrete pavement system are studied in order to identify a suitable method which will be incorperated in the pavement management system using nondestructive test and mechanistic evaluation. A typical four layered system is adopted and analyzed using 3 dimensional finite elements, plane strain elements, plates with Winkler foundation, and plates with Burmister foundation. Numerical analysis results of various structural analysis procedures are compared and analized based on displacements and stresses. It is concluded, after analysis of merits and demetits of the procedures, that Burmister foundation analysis procedure is the most sui-table procedure for implementation for the analysis of stresses and displacements because of its accuracy and simplicity.

• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.402-417
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• 2006

Research interest on functional food and phytochemicals has mainly focused on their health effects, mechanism of action and structure-activity relationship for the development of nutraceuticals. Considering the intake of phytochemicals via the normal diet, further information is required on changes in food functionality or individual phytochemicals that occur during the cooking or processing of foods, in order to increase the intake of these bioactive compounds, because many of the unit-operating procedures involved in cooking or food processing may result in physicochemical changes of food constituents. This study reviews the changes of selected phytochemicals, i.e. flavonoids, organosulfur compounds and carotenoids, or food functionality by major cooking or processing procedures such as heating, fermentation, and pH changes. In general, heating has a negative effect on food functionality, although in some cases, mild heating increases bioactive phytochemical contents. Some phytochemicals, including anthocyanins and catechins, are stabilized in lower pH conditions. The structures of phytochemicals, including isoflavones and catechins, are changed by fermentation. The loss of bioactive compounds may be decreased by recently developed cooking or processing methods such as microwave cooking or use of high hydrostatic pressure. However, the effects of cooking and processing procedures on food functionality and phytochemicals are so diverse and dependent on test conditions that further research efforts are needed to form accurate conclusions on the effects of cooking and processing of foods.

• Steel and Composite Structures
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• v.27 no.3
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• pp.355-370
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• 2018

In steel-concrete composite beams, longitudinal shear forces are transferred across steel flange-concrete slab interface by means of shear connectors. The connector behavior is highly non-linear and involves several complex mechanisms. The design resistance and stiffness of composite beams depends on the shear connection behavior and the accuracy in the connector resistance prediction is essential. However determining the stud shear resistance is not an easy process: analytical methods do not give an adequate response to this problem and it is therefore necessary to use experimental methods. This paper present a summary of the main procedures to predict the resistance of the stud shear connectors embedded in solid slab, and stud shear connectors in composite slab using profiled steel sheeting with rib perpendicular to steel beam. A large number of experimental studies on the behavior of stud shear connectors and reported in the literature are also summarized. A comparison of the stud shear resistance prediction using six reference codes (AISC, AASHTO, Eurocode-4, GB50017, JSCE and AS2327.1) and other procedures reported in the literature against experimental results is presented. From this exercise, it is concluded that there are still inaccuracies in the prediction of stud shear resistance in all analysed procedures and that improvements are needed.

• Asia-Pacific Journal of Business
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• v.11 no.2
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• pp.15-25
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• 2020

Purpose - The purpose of this study is to examine whether the change of settlement procedures have an impact on the distribution of day of the week effect in the UK and French markets or not. U.K and France changed their systems from fixed settlement date systems to fixed settlement lag systems Design/methodology/approach - This study adopted the data of the specific stock market indices such as FTSE 100 in the U.K market and FRCAC 40 in the French market, This study constructs a test of the differences in mean returns across the days of the week by computing the regression equations for each country index. Findings - First, this study found that the evolving settlement procedures in stock exchanges have an effect on stock return of day of the week. Second, long-run improvements in market efficiency may have diminished the effects of certain anomalies in recent periods. Improvements in market efficiency and evolving settlement systems may cause the disappearance of the weekend effect. Research implications or Originality - The Implication of this study is that recent settlement systems contributed to the disappearance of the weekend effect and explains improvements in market efficiency and diminishments of market anomaly. This study may be the first study which examines whether evolving settlement systems have an effect on the disappearance of the weekend effect in the market or not.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.20 no.3
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• pp.243-259
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• 2016

The Richards equation for water movement in unsaturated soil is highly nonlinear partial differential equations which are not solvable analytically unless unrealistic and oversimplifying assumptions are made regarding the attributes, dynamics, and properties of the physical systems. Therefore, conventionally, numerical solutions are the only feasible procedures to model flow in partially saturated porous media. The standard Finite element numerical technique is usually coupled with an Euler time discretizations scheme. Except for the fully explicit forward method, any other Euler time-marching algorithm generates nonlinear algebraic equations which should be solved using iterative procedures such as Newton and Picard iterations. In this study, lumped mass and distributed mass in the frame of Picard and Newton iterative techniques were evaluated to determine the most efficient method to solve the Richards equation with finite element model. The accuracy and computational efficiency of the scheme and of the Picard and Newton models are assessed for three test problems simulating one-dimensional flow processes in unsaturated porous media. Results demonstrated that, the conventional mass distributed finite element method suffers from numerical oscillations at the wetting front, especially for very dry initial conditions. Even though small mesh sizes are applied for all the test problems, it is shown that the traditional mass-distributed scheme can still generate an incorrect response due to the highly nonlinear properties of water flow in unsaturated soil and cause numerical oscillation. On the other hand, non oscillatory solutions are obtained and non-physics solutions for these problems are evaded by using the mass-lumped finite element method.

• Proceedings of the KIEE Conference
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• 2002.07a
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• pp.536-540
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• 2002

In this paper, accelerated life test (ALT) models and procedures for Magnetic Switch (MS) are developed and applied to assure specified reliability of the products at development phase and guarantee the life of the products. Magnetic contactor that functions with over-current relay is called MS. Magnetic contactor closes and opens the motor load with ON/OFF switch of electronic contactor. It is also used for protecting and controlling the load. Magnetic contactor detects the over-current flow in the load with a over-current relay and disconnects the load by opening its control power. In this study, ALT models for MS are developed using the relationship between stresses and life characteristics of products. Using the ALT models, we performed life tests and analyzed the tests results. The proposed ALT models and procedures may be extended and applied to testing similar kinds of products to reduce test times and costs of the tests remarkably. Finally the results of this study will contribute to improving reliability of products and strengthening competitiveness of our products in world markets.

• Journal of Advanced Navigation Technology
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• v.19 no.1
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• pp.1-6
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• 2015

Due to the rapid increase in air traffic worldwide, ICAO has replaced the existing navigation equipment with equipment based on satellite navigation. As a part of that work, ICAO was planning to replace conventional takeoff and landing service using ILS with GBAS. Unlike ILS, GBAS which uses precision approach service inducing aircraft to airport and satellite based augmentation system providing precise position information service surrounding airport is capable of providing a required performance by only a system, regardless of the number of systems, and has an advantage that it is possible curved approach. In this paper, fuel reduction of ILS approach procedures and GBAS curved approach procedures is estimated and determined by flight test in Taean Airport.

• The Journal of Advanced Prosthodontics
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• v.6 no.6
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• pp.451-455
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• 2014

PURPOSE. The most common failure seen in restorations with a zirconia core is total or layered delamination of the ceramic veneer. In the present study, the shear bond strengths between veneering ceramics and colored zirconia oxide core materials were evaluated. MATERIALS AND METHODS. Zirconia discs ($15{\times}12{\times}1.6mm$) were divided into 11 groups of 12 discs each. Groups were colored according to the Vita Classic scale: A3, B1, C4, D2, and D4. Each group was treated with the recommended shading time for 3 s, or with prolonged shading for 60 s, except for the control group. Samples were veneered with 3 mm thick and 3.5 mm in diameter translucent ceramic and subjected to shear test in a universal testing machine with a crosshead speed of 1 mm/min. One-way analysis of variance (ANOVA) and Tukey's HSD tests were used for comparisons of the groups having the same shading times. A paired t-test was used for groups of the same color (3 s/60 s). RESULTS. Among the 11 groups investigated C4 (3 s) had the highest bond strength with a value of 36.40 MPa, while A3 (3 s) showed the lowest bond strength with a value of 29.47 MPa. CONCLUSION. Coloring procedures can affect zirconia/ceramic bond strength. However, the results also showed that bond strengths of all the investigated groups were clinically acceptable.

• Journal of the Korean Geotechnical Society
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• v.19 no.2
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• pp.57-64
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• 2003

The liquefaction potential of saturated sands under seismic loading conditions has been carefully considered by many investigations. Typical of these investigations is the laboratory determination of cyclic strength of sands by means of cyclic triaxial tests. This study was conducted to investigate the effects of the method of sample preparation on the liquefaction characteristics of remolded samples of saturated uniform sands. Cyclic triaxial tests were performed on saturated uniform sand compacted to the same density by 3 different procedures of pluvial compaction through air, pluvial compaction through water and vibratory compaction. It was validated that the cyclic stress ratio of remolded saturated uniform sands by different compaction procedures at the same density was very different.