• Restorative Dentistry and Endodontics
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• v.26 no.2
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• pp.134-140
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• 2001

The polymerization shrinkage of composite resins is an important drawback although the composites have many advantages-more esthetic and conservative than metallic restoratives etc. The purposes of this research were to develop a new measurement method and to manufacture an instrument that can measure the initial dynamic volumetric shrinkage of composite resins during polymerization. The instrument was basically an electromagnetic balance that constructed with a force transducer using position sensitive photo detector(PSPD) and a negative feedback servo amplifier of proportional-derivative(PD) controller. The volumetric change of composites during polymerization was detected continuously as buoyancy change in distilled water by means of Archimedes's principle. It was converted to continuous electrical voltage signal in real time. The signal was properly conditioned and filtered and then it was stored in computer by a data acquisition(DAQ) board. By using this electronic instrument. the dynamic patterns of the polymerization shrinkage of eight commercial(Z-100, DenFil, AeliteFil, Z-250, P-60, SureFil, Synergy compact, and Tetric ceram) composite resins were measured and compared. The results were as follows. 1. From this project of developing instrument, the ability has been achieved that can acquire and process data of electrical signal transformed from various physical phenomenon by using temperature, displacement. photo. and force transducer. As a consequence, the instrumentation and measurement system used to analyze the physical characteristics of various dental materials in dental research field can be designed, manufactured and implemented in lab. 2. This instrument has some advantages. It was insensible to temperature change and could measure true dynamic volumetric shrinkage in real time without complicated process. It showed accuracy and high precision results with small standard deviation. 3. The polymerization shrinkage of composites was significantly different between brands and ranged from 2.47％ to 3.89％, The order of polymerization shrinkage was as follows, in order of increasing shrinkage, SureFil, P60, Z250, Z100, Synergy compact. DenFil, Tetric ceram, and AeliteFil. 4. The polymerization shrinkage rate per unit time, dVol％/dt, showed that the instrument can provide an indirect research method for polymerization reaction kinetics.

• Korean Journal of Microbiology
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• v.23 no.2
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• pp.77-83
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• 1985

The aim of this investigation was to resolve the contradiction between the results of Sternberg and Mandels (1980, 1982)and those of Nisizawa et al., (1971) in cellulase induction by sophorose, and furthermore to study the conditional effects in sophorose-induced cellulase induction in Trichoderma reesei QM 9414. Sophorose could induce the synthesis of CMCase and ${\beta}-glucosidase$ simultaneously. Optimal induction medium by sophorose had the potassium citrate buffer solution of pH 3.0-4.0 for CMCase, but one of pH 5.0-6.0 for ${\beta}-glucosidase$. At this time, two different types of ${\beta}-glucosidase$ could be induced by sophorose: one was extracellular and had maximum at pH 5.0, the other was intracellular and had maximum activity at pH6.5. Induction study showed that $methyl-{\beta}-glucoside$ was not a true inducer of ${\beta}-glucosidase$ and that large ${\beta}-glucosidase$ induction could be obtained only by the addition of sophorose into the induction medium. Glucose repressed the induction of cellulase by sophorose. The repression of glucose could not be overcome by the addition of cyclic AMP into the induction medium.

• Journal of Korea Game Society
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• v.9 no.3
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• pp.35-42
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• 2009

Analyzing the aspects of pattern in MMORPG that has been leading our domestic game industry to the climax, our game industry might be thought to orient the space narrative storytelling method containing the leading life in the virtual sociality to the nature of society. It is essential to have the convergence and linkage between media in describing the lifestyle in the virtual society, which should be operated in a very flexible manner. It is, however, true that we are lacking of the quantification of designing process until now, although the designing process should have the vivid academic functions between media in advance. In addition, the designing crossing over the MMORPG genre along with the game patterns in the MMORPG genre has close correlations with the spectrum of crises emerging recently in our domestic online game industry. In other words, this essay aims at raising an issue that the selective method to the lifestyle in the virtual society being settled down as characteristics inherent to the methods of our domestic online games might deliver the improving effects through the establishment of game designing jobs and compliant plans.

• Journal of Digital Contents Society
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• v.11 no.4
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• pp.597-606
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• 2010

This paper describes a real-time camera tracking framework specifically designed to track a monocular camera in an AR workspace. Typically, the Kalman filter is often employed for the camera tracking. In general, however, tracking performances of conventional methods are seriously affected by unpredictable situations such as ambiguity in feature detection, occlusion of features and rapid camera shake. In this paper, a recursive Bayesian sampling framework which is also known as the particle filter is adopted for the camera pose estimation. In our system, the camera state is estimated on the basis of the Gaussian distribution without employing additional uncertainty model and sample weight computation. In addition, the camera state is directly computed based on new sample particles which are distributed according to the true posterior of system state. In order to verify the proposed system, we conduct several experiments for unstable situations in the desktop AR environments.

• Journal of the Korea Fashion and Costume Design Association
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• v.23 no.1
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• pp.113-127
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• 2021

This study aims to analyze the style of men's suits and extract expressional words for the development of semantic differential scales of visual images according to the change in silhouette. Research methods are literature studies, case studies, and questionnaires. The stimuli were created using CLO 3D, a virtual sewing CAD. This study's results are as follows: 1) The British suit jacket has an angled shoulder line using thin pads, and a slightly higher waistline. The pants of the suit have a high waistline and two pleats, so the thighs of the pants are wide. The American suit jacket has a natural shoulder line, and the waistline is not emphasized. The width of the jacket is relaxed, and the length is long. The pants of the suit have a higher waistline, and the pants are wide as well. The Italian suit jacket has wide shoulders, and the waistline is connected lower with a soft curve, and the length is relatively short. The trousers of the suit are tapered and get narrower as it goes down to the hem. 2) Because it originated in the practices of true bespoke tailoring, traditional British suits have a far more 'fitted' silhouette than the mass-produced styles that became emblematic of the American style. By the late 1950s, a sack-style suit was standard American business attire. This technique gives the sack suit its characteristically 'boxy' silhouette. The "Continental" presented a highly tailored silhouette, with padded shoulders, a slim, tight-fitting chest, and a closely tapered waist. The story was that Italian culture valued aesthetics over all else and thus sought the 'slim' suit style as much as possible. 3) The main expressional words of visual images for men's suits differ greatly depending on the silhouette of suit. The visual images are ranked in the order of 'neat', 'classic', 'educated', 'hard', 'mature', for fitted silhouettes. The words of 'masculine', 'basic', 'comfortable', 'simple', 'mature', 'conservative', 'modern', are ranked for boxy silhouettes. And the words of 'slim', 'young', 'neat', are noted for slim silhouettes.

• Journal of Animal Science and Technology
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• v.55 no.5
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• pp.343-349
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• 2013

Data including 1,372,050 milk records pertaining to 438,019 cows from 1983 to 2011 collected during performance tests conducted by the National Livestock Cooperative Dairy Improvement Center were used to calculate milk income and profit of individuals and investigate the effects of production levels of early lactation (parity 1 and 2, respectively). Individuals with a moderate level of early lactation stayed longer in herds. Among parity 1, the 9,000 kg or higher group had a lower mean number of lactations than the overall mean of 3.13. The 7,000 kg or lower and 10,000 kg or higher groups had lower mean life time milking days than the overall mean of 1,076.8 days. Standard deviations of lifetime traits tended to decrease as production levels increased. For parity 2, the 11,000 kg or higher group had a lower mean number of lactation than the overall mean of 3.43. The lifetime milking days was highest in the 12,000 kg group (1,212.0 days), and generally smaller in the lower groups. Profit increased as the production level of groups increased for both parity 1 and 2. In groups with low production levels, profit of parity 1 was higher than that of parity 2, while the reverse was true in groups with high production levels. These results suggest that individuals in the low production groups had a greater likelihood to be culled due to reproductive or other problems. Furthermore, the accuracy of the prediction of lifetime profit of individuals with a milk yield of 305 days seems to be higher for parity 2 than parity 1; therefore, it is desirable to predict lifetime profit using the 305d milk yield of parity 2. In conclusion, breeding goals are based on many factors in functions for the estimation of profit; however, production levels during early lactation (parity 1 and 2) can be used as indicators of profit to extend profitability.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.159-163
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• 2005

The propriety between suppliers and demanders in geometric design is very important. Although the final purpose of constructing roads is to concern about the driver s comfort, unfortunately, it has not been considered so far. We've considered the regularity and quickness in considering driver's comfort but there should be considered the safety for the accident as well. If drivers are appeared to be more speeding than designer's intention, there will be needed some supplements to increase the safety rate for the roads. Even if both an upward and downward section are supposed to exist at the same time for solid geometry of the roads like this, it is true that the recent design for the 3-D solid geometry section has been done as flat 2-D and the minimum plane curve radius and the maximum cant have been decided just by calculating without considering operating speed between an upward and downward section at the same point. In this investigation, thus, I'd like to calculate the safety of the cant by considering the speed features of the solid geometry for the first lane of four lane rural roads. To begin with, we investigated the driving speed of the car, which is not been influenced by a preceding car to analyze the influence of the geometrical structure by using Nc-97. Secondly, we statistically analyzed the driving features of the solid geometry after comparing the 6 sections, that is, measuring the driving speed feature at 12 points and combining the influence of the vertical geometry and plane geometry to the driving speed of the plane curve which was researched before. Finally, we estimated the value of cant which considers the driving speed not by using it which has applied uniformly without considering it properly, though there were some differences between a designed speed and driving speed through the result of the basic statistical analysis but by introducing the new safety rate rule, a notion of ${\alpha}$. As a result of the research, we could see the driving features of the car and suggest the safety rate which considers these. For considering the maximum cant, if we apply the safety rate, the result of this experiment, which considers 3-D solid geometry, there'll be the improvement of the driver's safety for designing roads. In addition, after collecting and analyzing the data for the road sections which have various geometrical structures by expanding this experiment it is considered that there should be developed the models which considers 3-D solid geometry.

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.191-202
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• 2007

To identify the detailed attenuation structure in the southern Korean Peninsula, a numerical test was conducted for the Q tomography inversion to be applied to the accumulated dataset until 2005. In particular, the stochastic pointsource ground-motion model (STGM model; Boore, 2003) was adopted for the 2D Q tomography inversion for direct application to simulating the strong ground-motion. Simultaneous inversion of the STGM model parameters with a regional single Q model was performed to evaluate the source and site effects which were necessary to generate an artificial dataset for the numerical test. The artificial dataset consists of simulated Fourier spectra that resemble the real data in the magnitude-distance-frequency-error distribution except replacement of the regional single Q model with a checkerboard type of high and low values of laterally varying Q models. The total number of Q blocks used for the checkerboard test was 75 (grid size of $35{\times}44km^2$ for Q blocks); Q functional form of $Q_0f^{\eta}$ ($Q_0$=100 or 500, 0.0 < ${\eta}$ < 1.0) was assigned to each Q block for the checkerboard test. The checkerboard test has been implemented in three steps. At the first step, the initial values of Q-values for 75 blocks were estimated. At the second step, the site amplification function was estimated by using the initial guess of A(f) which is the mean site amplification functions (Yun and Suh, 2007) for the site class. The last step is to invert the tomographic Q-values of 75 blocks based on the results of the first and second steps. As a result of the checkerboard test, it was demonstrated that Q-values could be robustly estimated by using the 2D Q tomography inversion method even in the presence of perturbed source and site effects from the true input model.

• Journal of Korean Orthopaedic Sports Medicine
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• v.7 no.2
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• pp.128-134
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• 2008

Purpose: We prospectively evaluated the clinical usefulness of the patellar inferior pole (PIP) as a landmark of the anteromedial (AM) portal for the arthroscopic surgery of the medial mensiscus posterior horn (MMPH). Materials and Methods: Group 1 (50 normal left knees of adults), Group 2 (10 normal knees under anesthesia), and Group 3 (50 consecutive knees undergoing elective arthroscopic surgery for relatively simple intraarticular pathologies, or diagnostic arthroscopy) were included. In Group 1 and 2, the true lateral (A) and valgus stress lateral radiographs (B) on $30^{\circ}$ flexion were obtained, and the lines (AM portal line) passing through the PIP and distal-most medial femoral condyle (MFC) were drawn under the condition without considering the thickness of articular cartilage of MFC (1, 2-A, B group), and considering it as 2.5mm on B (1, 2-C group). Then, we investigated the meeting point of the AM portal line with medial tibial plateau (C-D percentage), and measured the distance between the PIP and the anterior joint line (E-length), and medial tibial-femoral joint space (F-length). In Group 3, the AM portal was made at the PIP level and clinical usefulness of the approach to the MMPH and body of the lateral meniscus (LM) was analyzed. Results: The average C-D percentage came out as 85.8, 101.3, 69.1% for each Group 1-A, B, C, and 102.4, 144.6, 116.8% for each Group 2-A, B, C. Measured E-length was an average of 15.1 (Group 1-A), 15.5 (Group 1-B, C), 13.1 (Group 2-A), and 12.9 mm (Group 2-B, C) and the change by valgus stress had no statistical significance. The F-length increased about 1.2 (Group 1) and 3.6 mm (Group 2) when valgus stress was applied, which had statistical significance (p<0.001, p<0.001). In Group 3, 49, 48 knees were classified as good for the MMPH, and the body of LM in aspect of the clinical usefulness of AM portal made on the PIP level. Conclusion: We identified the clinical usefulness of the PIP as a skin landmark of AM portal for the arthroscopic surgery of the MMPH.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.11
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• pp.1638-1643
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• 2014

This study was conducted to compare carcass characteristics and physico-chemical meat quality in two different genotype ducks raised under identical feeding and rearing conditions. A total of ninety 1-d-old Korean native ducks (KND, n = 45) and commercial meat-type ducks (Grimaud, n = 45) were fed same experimental diets during 56 d and 42 d, respectively to obtain similar slaughter weights. The experimental diet for starter period contained 20% crude protein (CP) and 2,900 kcal nitrogen corrected true metabolizable energy (TMEn)/kg of diet and that for grower period contained 17% CP and 3,050 TMEn/kg of diet. Average daily gain and feed efficiency of KND were inferior to those of commercial meat-type ducks (p<0.05). Carcass weight was not different between two genetically different ducks, but carcass yield of KND was significantly higher (p<0.05) than that of commercial meat-type ducks. There were no significant differences in cooking loss and pH of breast meat between two genetically different ducks, but water holding capacity of KND was significantly higher than that of commercial meat-type ducks. The linoleic acid and total polyunsaturated fatty acid of breast meat from KND were significantly higher (p<0.05) than the corresponding part from commercial meat-type ducks. Significant differences were detected in water holding capacity and the content of linoleic acid and polyunsaturated fatty acid, which were significantly higher in KND, whereas growth performance tended to be superior in commercial ducks. At the market weight, the meat from KND was judged to have better qualities with regard to higher water holding capacity and greater content of polyunsaturated fatty acid compare with meat from commercial meat-type duck.