• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.499-510
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• 2010

This paper presents a systematic approach for estimating material performance and designing mix proportion of concrete based on an application of Bayesian method in the form of satisfaction curves. The one-parameter satisfaction curve represents a satisfaction probability of a concrete performance criterion as a function of concrete material parameter. An analysis method to combine multiple satisfaction curves to form one unique satisfaction curve that can relate the performance of concrete to a single evaluating value called Goodness value is proposed. A proposed PBMD procedure and examples of application of the PBMD method for concrete mix proportion design are carried out to verify the validity of the proposed method. Finally, the comparison between the expected performance results of a concrete mix proportion designed using PBMD to the ACI estimation equation calculated results are performed to check the applicability of the method to actual construction.

• The Journal of Advanced Prosthodontics
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• v.7 no.3
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• pp.224-232
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• 2015

PURPOSE. The purpose of this study was to find out the effect of immediate dentin sealing (IDS) on bond strength of ceramic restoration under various thermocycling periods with DBA (dentin bonding agent system). MATERIALS AND METHODS. Fifty freshly extracted human mandibular third molars were divided into 5 groups (1 control and 4 experimental groups) of 10 teeth. We removed enamel layer of sound teeth and embedded them which will proceed to be IDS, using All Bond II. A thermocycling was applied to experimental groups for 1, 2, 7, 14 days respectively and was not applied to control group. IPS Empress II for ceramic was acid-etched with ceramic etchant (9.5% HF) and silane was applied. Each ceramic disc was bonded to specimens with Duo-link, dual curable resin cement by means of light curing for 100 seconds. After the cementation procedures, shear bond strength measurement and SEM analysis of the fractured surface were done. The data were analyzed with a one-way ANOVA and Tukey multiple comparison test (${\alpha}$=.05). RESULTS. There were no statistically significant differences between 4 experimental groups and control group, however the mean value started to decrease in group 7d, and group 14d showed the lowest mean bond strength in all groups. Also, group 7d and 14d showed distinct exposed dentin and collapsed hybrid layer was observed in SEM analysis. CONCLUSION. In the present study, it can be concluded that ceramic restorations like a laminate veneer restoration should be bonded using resin cement within one week after IDS procedure.

• Communications for Statistical Applications and Methods
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• v.24 no.3
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• pp.241-254
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• 2017

Drawing a sample can be costly or time consuming in some studies. However, it may be possible to rank the sampling units according to some baseline auxiliary covariates, which are easily obtainable, and/or cost efficient. Ranked set sampling (RSS) is a method to achieve this goal. In this paper, we propose a modified approach of the RSS method to allocate units into an experimental study that compares L groups. Computer simulation estimates the empirical nominal values and the empirical power values for the test procedure of comparing L different groups using modified RSS based on the regression approach in analysis of covariance (ANCOVA) models. A comparison to simple random sampling (SRS) is made to demonstrate efficiency. The results indicate that the required sample sizes for a given precision are smaller under RSS than under SRS. The modified RSS protocol was applied to an experimental study. The experimental study was designed to obtain a better understanding of the pathways by which positive experiences (i.e., goal completion) contribute to higher levels of happiness, well-being, and life satisfaction. The use of the RSS method resulted in a cost reduction associated with smaller sample size without losing the precision of the analysis.

• Archives of Plastic Surgery
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• v.47 no.5
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• pp.451-459
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• 2020

Background For volar soft tissue defects of the proximal interphalangeal (PIP) joint, free flaps are technically challenging, but have more esthetic and functional advantages than local or distant flaps. In this study, we compared the long-term surgical outcomes of arterial (hypothenar, thenar, or second toe plantar) and venous free flaps for volar defects of the PIP joint. Methods This was a single-center retrospective review of free flap coverage of volar defects between the distal interphalangeal and metacarpophalangeal joint from July 2010 to August 2019. Patients with severe crush injuries (degloving, tendon or bone defects, or comminuted/intra-articular fractures), thumb injuries, multiple-joint and finger injuries, dorsal soft tissue defects, and defects >6 cm in length were excluded from the study, as were those lost to follow-up within 6 months. Thirteen patients received arterial (hypothenar, thenar, or second toe plantar) free flaps and 12 received venous free flaps. Patients' age, follow-up period, PIP joint active range of motion (ROM), extension lag, grip-strength ratio of the injured to the uninjured hand, and Quick Disabilities of Arm, Shoulder & Hand (QuickDASH) score were compared between the groups. Results Arterial free flaps showed significantly higher PIP joint active ROM (P=0.043) and lower extension lag (P =0.035) than venous free flaps. The differences in flexion, grip strength, and QuickDASH scores were not statistically significant. Conclusions The surgical outcomes of arterial free flaps were superior to those of venous free flaps for volar defects of the PIP joint.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1624-1628
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• 2015

Rigorously standardized laboratory protocols are essential for meaningful comparison of data from multiple sites. Considering that interactions of minerals with organic matrices may vary depending on the material nature, there could be peculiar demands for each material with respect to digestion procedure. Acid digestion procedures were evaluated using different nitric to perchloric acid ratios and one- or two-step digestion to estimate the concentration of calcium, phosphorus, magnesium, and zinc in samples of carcass, bone, excreta, concentrate, forage, and feces. Six procedures were evaluated: ratio of nitric to perchloric acid at 2:1, 3:1, and 4:1 v/v in a one- or two-step digestion. There were no direct or interaction effects (p>0.01) of nitric to perchloric acid ratio or number of digestion steps on magnesium and zinc contents. Calcium and phosphorus contents presented a significant (p<0.01) interaction between sample type and nitric to perchloric acid ratio. Digestion solution of 2:1 v/v provided greater (p<0.01) recovery of calcium and phosphorus from bone samples than 3:1 and 4:1 v/v ratio. Different acid ratios did not affect (p>0.01) calcium or phosphorus contents in carcass, excreta, concentrate, forage, and feces. Number of digestion steps did not affect mineral content (p>0.01). Estimated concentration of calcium, phosphorus, magnesium, and zinc in carcass, excreta, concentrated, forage, and feces samples can be performed using digestion solution of nitric to perchloric acid 4:1 v/v in a one-step digestion. However, samples of bones demand a stronger digestion solution to analyze the mineral contents, which is represented by an increased proportion of perchloric acid, being recommended a digestion solution of nitric to perchloric acid 2:1 v/v in a one-step digestion.

• Journal of Yeungnam Medical Science
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• v.5 no.2
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• pp.53-58
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• 1988

KOH examination is a simple, rapid and diagnostic procedure to confirm dermatophytic infections. It is important to select a proper examination site of the lesion. To determinate the proper examination site of the lesion, mycologic studies were done with multiple specimens collected from the center, margin and out of margin of the ring-shaped dermatophytotic skin lesion on the 58 patients. The results were as follows. Positive rate of KOH wet smear was 94.8% at the center and 100% at the margin of the lesions, 22.4% at the 1cm and 5.2% at the 2cm out of the lesions. The more hyphae were found in the lesion, the more hyphae were found out of the lesion. Culture was done on the Sabouraud's glucose agar from the highest KOH positive area and the positive culture was 48 strains(82.8%) of 58 patients. These findings suggested that the ring-shaped active margin was the best site to examine mycologic studies.

• Journal of Advanced Navigation Technology
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• v.19 no.3
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• pp.192-198
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• 2015

Since instrument landing system currently operating in most airports is operating in single-pass, it is not possible to accommodate a large number of aircraft. A satellite navigation system GBAS using a GNSS has been developed to solve these limitation when air traffic increases. GBAS is better than the ILS in position accuracy and capable of landing through multiple paths rather than a single path, the aircraft can perform varied landing procedures. In this paper, after we established a virtual ILS procedures at Taean Airfield in which ILS installation is impossible due to environmental requirements and airspace restrictions, flight test was performed by Cessna Skyhawk 172 to compare the virtual ILS procedures and curved approach procedure and the advantage of curved approach was confirmed.

• Journal of the Korean Society of Radiology
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• v.6 no.2
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• pp.107-114
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• 2012

The study was conducted in patients who had undergone angiography and arterial embolization after being diagnosed with arterial bleeding among those registered with severe trauma at the admission to the department of emergency due to accidents. In the study, comparison was done between the survived group and the nonsurvived group to investigate the usefulness and the optimal performance timing of angiography and embolization as the survival-affecting factors and treatment methods for patients. The study was performed as a retrospective analysis in 45 patients who had undergone angiography and arterial embolization among those categorized as severe trauma patients from the emergency department of H hospital located in Gyeonggi-do from July, 2006 until December, 2010. The Injury Severity Score (ISS), the Revised Trauma Score (RTS), the hematocrit were the main outcome measurements. Arterial embolization was technically successful in all cases, transcatheter arterial embolization of arterial bleeding is a useful procedure in lowering the mortality and complication in severe trauma patients. and RTS, ISS, Hematocrit were the predictable early mortality factors. So bad vital sign patients must be progressed rapidly.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.9 s.114
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• pp.897-903
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• 2006

The reduction of the vehicle interior noise has been the main interest of noise and vibration harshness (NVH) engineers. The driver's perception on the vehicle noise is affected largely by psychoacoustic characteristic of the noise as well as the SPL. In particular, the heating, ventilation and air conditioning (HVAC) system sound among the vehicle interior noise has been reflected sensitively in psychoacoustics view point. Even though the HVAC noise is not louder than overall noise level, it clearly affects subjective perception to drivers in the way of making to be nervous or annoyed. Therefore, these days a vehicle engineer takes aim at developing sound quality as well as reduction of noise. In this paper, we acquired noises in the HVAC from many vehicles. Through the objective and subjective sound quality (SQ) evaluation with acquiring noises recorded by the vehicle HVAC system, the simple and multiple regression models were obtained for the subjective evaluation 'Pleasant' using the semantic differential method (SDM). The regression procedure also allows you to produce diagnostic statistics to evaluate the regression estimates including appropriation and accuracy. Furthermore, the neural network (NN) model were obtained using three inputs(loudness, sharpness and roughness) of the SQ metrics and one output(subjective 'Pleasant'). Because human's perception is very complex and hard to estimate their pattern, we used NN model. The estimated models were compared with correlations between output indexes of SQ and hearing test results for verification data 'Pleasant'. As a result of application of the SQ indexes, the NN model was shown with the largest correlation of SQ indexes and we found possibilities to predict the SQ metrics.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.677-684
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• 2017

Smart devices are used in a variety of industries, because applications for them are easy to develop and portable. However, industrial equipment can cause security problems for information and accidents when controlling the actuator of the equipment at a remote location. In this paper, we studied methods of solving these problems and the advantages of applying smart control systems to industrial equipment. We propose a manual manipulation method using queries and a smart control access procedure for controlling equipment using a smart device. In addition, we propose a data transmission method employing multiple encryption protocols and a user authentication method using unique information from the smart device and Q & A as the communication data protection and user authentication methods, respectively. In order to evaluate its performance, an operation test of the smart control system and user authentication comparison experiment were performed. In order to understand the advantages of applying the smart control system to the equipment, we conducted a comparative experiment with a teach pendant and evaluated its reaction time in case of error.