• Imaging Science in Dentistry
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• 제44권1호
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• pp.7-13
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• 2014

Purpose: This study was performed to evaluate the prevalence of all types and subtypes of dental anomalies among 7- to 35-year-old patients by using panoramic radiographs. Materials and Methods: This cross-sectional study was conducted on 1649 people in Hamadan City, in 2012-2013. The prevalence of four types and 12 subtypes of dental anomalies was evaluated by two observers separately by using panoramic radiography. Dental anomalies were divided into four types: (a) shape (including fusion, taurodontism, and dens invagination); (b) number (including hypodontia, oligodontia, and hyperdontia); (c) structure (including amelogenesis imperfecta, dentinogenesis imperfecta, and dentin dysplasia); and (d) position (including displacement, impaction, and dilacerations). Results: The reliability between the two observers was 79.56% according to the Kappa statistics. The prevalence of dental anomalies diagnosed by panoramic radiographs was 29%. Anomalies of position and number were the most common types of abnormalities, and anomalies of shape and structure were the least in both genders. Anomalies of impaction (44.76%), dilacerations (21.11%), hypodontia (15.88%), taurodontism (9.29%), and hyperdontia (6.76%) were the most common subtypes of dental anomalies. The anomalies of shape and number were more common in the age groups of 7-12 years and 13-15 years, respectively, while the anomalies of structure and position were more common among the other age groups. Conclusion: Anomalies of tooth position were the most common type of dental anomalies, and structure anomalies were the least in this Iranian population. The frequency and type of dental anomalies vary within and between populations, confirming the role of racial factors in the prevalence of dental anomalies.

• 수산해양교육연구
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• 제26권1호
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• pp.108-125
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• 2014

Although South Korea had managed fishery resources based on elements included in the fishery like fisheries licence, after agreeing on UN Convention on the law in 1999, it became inevitable to adopt TAC that regulates yield. Therefore, currently operating an indecisive system by maintaining the fisheries license system while applying TAC only to some fisheries. However, it became imperative to find ways to improve the current system as it dose not solve problems such as decrease of fishery resources and catch per unit effort, excessive input of fishing boats, rising costs for fishery management, and shortage of fishery population. For those reasons, it is time to review ITQs, which is recognized globally as the most innovative fisheries management system. To adopt the ITQs, it seems necessary to compare how the fisheries act of New Zealand which is currently most successfully operated and Fisheries Resources Management Act of Korea. To do so, in this study, the provisions on TAC of the two countries are compared to analyze the institutional necessity for Korea to adopt ITQs. The following conclusions have been made : First, it will be necessary to gradually expand the species and fisheries for which TAC is enforced, and accumulate correct data on fisheries resources. Second, while forcing traders to obtain license as well, the species and quantity of traded fisheries must be reported separately for cross-checking with the catch reported by the fisheries. Third, the number of observers must be increased and report the species and quantity of the catch to person in charge at the relevant port, and observers must check the report before disembarkation. Fourth, penalty for violating Fisheries resources management act must be enhanced, especially regarding false report of fishery activities and catch.

• 사상체질의학회지
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• 제16권3호
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• pp.46-58
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• 2004

1. Objectives This study was performed by means of perceptual evaluation of the voices of Sasang Constitution. 2. Methods 73 female subjects were classified by means of 3 kinds of Questionnaire papers(QSCCII, QSCCI, Sasang Pattern Identification Questionnaire). So they were categorized into 3 groups, 23 Soyangin, 28 Taeumin and 22 Soeumin. 73 voice samples were presented three times to a group of 5 judges. The time interval between ratings was 14 days. The four goals of this study were to evaluate the intraobserver reliability between each rating, to evaluate the interobserver reliability, to evaluate the reliability between the each rating and Questionnaire result and to make the notion of the consensus of Sasang Constitution's Voice. 3. Results & Conclusions The intraobserver reliability between the first and second rating showed significance statistically among all observers. And the intraobserver reliability between the second and third rating showed significance except one observer. The interobserver reliability among the three ratings showed significance statistically except one to two observers in the first rating and other one to another one in the second rating. In the reliability between the each rating and Questionnaire result, one in the first rating, other one in the second rating and another two in the third rating showed significance. To make the notion of the consensus of Sasang Constitution's Voice, classification into 4 categories was made: clear/hoarse, high/low, fast/slow, powerful/powerless. The voice of Soyangin group was classified as powerful and fast, and that of Taeumin group as powerful, hoarse and low and that of Soeumin group as powerless and slow.

• 대한디지털의료영상학회논문지
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• 제14권2호
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• pp.57-61
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• 2012

To compare the accuracy of breath-hold magnetic resonance imaging sequences to establish the most effective superparamagnetic iron oxide-enhanced sequence for detection of hepatic metastases. A total of 100 patients(50men and 50women, mean age: 60years) with liver disease(including malignant and benign liver lesions) were investigated at 3.0T machine (GE, General Electric Medical System, Excite HD) with 8Ch body coil. Pulse sequence for MR imaging decided to the FS-T2-FSE-RT(TR/TE/Thick./Freq./Phase=12857ms/100ms/7mm/512/384), MGRE(TR/TE/Thick./Freq./Phase=100ms/9.7ms/7mm/384/288), in-out of phase echo(TR/$TE_1$, $TE_2$/Thick./Freq./Phase=140ms/2.4, 5.8ms/7mm/352/300), Images obtained before the injection of SPIO. Six sequences were optimized for lesion detection: FS-T2-FSE-RT, multigradient recalled echo data image(MGRE), T2-weighted MGRE with an 9.7msec echo time. Images were reviewed independently by five blinded observers. The accuracy of each sequence was measured by using picture archiving communication system analysis. All results were correlated with findings at multidectator computed tomography examination. Differences between the mean results of the six observers were measured by using paired student t-test analysis. Postcontrast T2-weighted MGRE sequences were the most accurate and were significantly superior to postcontrast FS-T2-FSE-RT, T2-weighted MGRE, in-out of phase MR sequences(p < .05). For all lesions that were malignant or smaller than 1 cm, respectively, contrast to noise ratio of pre and postcontrast sequences were -1and -0.3 for T2-weighted FSE, 0.53 and 4.5 in-out of phase, 7, 7.08, 5.08, 3.32, 1.7, 1.16, 0.79, 0.68 for GRE with 2.9, 7.5, 12.1, 16.6, 21.2, 25.8, 30.4, 35.0 TE values. Breath-hold various TE precontrast sequences offer improvement in sensitivity compared with fixed multigradient recalled echo sequences alone.

• Imaging Science in Dentistry
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• 제32권4호
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• pp.213-219
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• 2002

Purpose : Computed radiography (CR) has been used in cephalometric radiography and many studies have been carried out to improve image quality using various digital enhancement and filtering techniques, During CR image acquisition, the frequency rank and type affect to the image quality. The aim of this study was to compare the diagnostic quality of conventional cephalometric radiographs to those of computed radiography. Materials and Methods : The diagnostic quality of conventional cephalometric radiographs (MO) and their digital image counterparts were compared, and at the same time, six modalities (M1-M6) of spatial frequency-processed digital images were compared by evaluating the reproducibility of 23 cephalometric landmark locations. Reproducibility was defined as an observer's deviation (in mm) from the mean between all observers. Results and Conclusion: In comparison with the conventional cephalometric radiograph (MO), Ml showed statistically significant differences in 8 locations, M2 in 9, M3 12, M4 in 7, M5 in 12, and M6 showed significant differences in 14 of 23 landmark locations (p < 0.05). The number of reproducible landmarks that each modality possesses were 7 in M6, 6 in M5, 5 in M3, 4 in M4, 3 in M2, 2 in Ml, and 1 location in MO. The image modality that observers selected as having the best image quality was M5.

• Imaging Science in Dentistry
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• 제46권2호
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• pp.87-92
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• 2016

Purpose: The aim of this study was to assess and compare the diagnostic performance of panoramic and occlusal radiographs in detecting submandibular sialoliths. Materials and Methods: A total of 40 patients (20 cases and 20 controls) were included in this retrospective study. Cases were defined as subjects with a submandibular sialolith confirmed by computed tomography (CT), whereas controls did not have any submandibular calcifications. Three observers with different expertise levels assessed panoramic and occlusal radiographs of all subjects for the presence of sialoliths. Intraobserver and interobserver agreement were assessed using the kappa test. Sensitivity, specificity, accuracy, positive and negative predictive values, and the diagnostic odds ratio of panoramic and occlusal radiographs in screening for submandibular sialoliths were calculated for each observer. Results: The sensitivity and specificity values for occlusal and panoramic radiographs all ranged from 80% to 100%. The lowest values of sensitivity and specificity observed among the observers were 82.6% and 80%, respectively (P=0.001). Intraobserver and interobserver agreement were higher for occlusal radiographs than for panoramic radiographs, although panoramic radiographs demonstrated a higher overall accuracy. Conclusion: Both panoramic and occlusal radiographic techniques displayed satisfactory diagnostic performance and should be considered before using a CT scan to detect submandibular sialoliths.

• 수산경영론집
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• 제33권1호
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• pp.1-18
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• 2002

The observer program is being utilized In various fishing areas and fisheries internationally and nationally due to the its expected effectiveness in fisheries management and the collection of bioeconomic data necessary in fisheries management policy. The timely gathered data by observers play substantially a major role in decision-making fisheries policy such as the change in management measures, the application of season closure and area closure and etc. The expected effectiveness of the observer program In fisheries management, generally mentioned, is that it would lead to the increase in stock size from which the level of harvest would consequently increases. This study is aimed to analyze this tentatively expected effectiveness of the observer program in fisheries management. The changes in stock size and the level of harvest over time are analyzed under the observer program assuming the fishermen bear the cost of the observer program by investigating the change in fisherman's fishing activity under the observer program and by combining this changed activity with the biological model. The level of fishing efforts of fishermen was decreased from the results of the increase in fishing cost caused by the observer cost and the decrease in catchable stock size restricted by observers. This reduced level of fishing efforts enables stock size to increase over time and therefore, the expected level of harvest increases as time goes on. Another benefit under the observer program is to reduce management costs from the fact that fishermen are responsible for the cost of the observer program and the avoidance cost of fisherman responding to the fisheries regulation could be eliminated from the surveillance of observer. Therefore, it may possible to accomplish the cost-efficient fisheries management policy.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제40권
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• pp.20.1-20.10
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• 2018

Background: In the absence of clear guidelines for facial aesthetic surgery, most surgeons rely on expert intuitive judgement when planning aesthetic and reconstructive surgery. One of the most famous theories regarding "ideal" facial proportions is that of the golden proportion. However, there are conflicting opinions as to whether it can be used to assess facial attractiveness. The aim of this investigation was to assess facial ratios of professional black models and to compare the ratios with the golden proportion. Methods: Forty photographs of male and female professional black models were collected. Observers were asked to assign a score from 1 to 10 (1 = not very attractive, 10 = very attractive). A total of 287 responses were analysed for grading behaviour according to various demographic factors by two groups of observers. The best graded photographs were compared with the least well-graded photographs to identify any differences in their facial ratios. The models' facial ratios were calculated and compared with the golden proportion. Results: Differences in grading behaviour were observed amongst the two assessment groups. Only one out of the 12 facial ratios was not significantly different from the golden proportion. Conclusions: Only one facial ratio was observed to be similar to the golden proportion in professional model facial photographs. No correlation was found between facial ratios in professional black models with the golden proportion. It is proposed that an individualistic treatment for each ratio is a rather better method to guide future practice.

• 치과방사선
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• 제26권2호
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• pp.147-152
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• 1996

Six observers with different amount of experience in the field of Oral and Maxillofacial Radiology interpreted the radiographs of 13 cases of ameloblastoma and 8 cases of odontogenic keratocyct which were confirmed histopathologically and showed pseudo-multilocular appearance and scalloped border radiographically. The authors examined the accuracy of radiologic diagnoses, interobserver agrement and intraobserver agreement. The obtained results were as follows; 1. The accuracy of radiologic diagnosis ranged from 0.48 to 0.81. The average value was 0.61. 2. The accuracy of radiologic diagnosis for ameloblastoma(0.55) was lower than that for odontogenic keratocyst(0.70) (P<0.05). 3. The overall agreement among the 6 observers was 14.3％ at the first interpretation and 19.0％ at the second interpretation. 4. The intraobserver agreement of each observer expressed in kappa index ranged from -0.14 to 0.64. The overall intraobserver agreement was 0.29. 5. The intraobserver agreement of each observer for ameloblastoma and odontogenic keratocyst ranged from -0.07 to 0.65 and from -0.25 to 1.00, respectively. The overall intraobserver agreement for ameloblatoma and odontogenic keratocyst were 0.27 and 0.26, respectively. 6. The diagnostic accuracy highly correlated to the intraobserver agreement(r=0.6370).

• Restorative Dentistry and Endodontics
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• 제12권2호
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• pp.65-72
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• 1987

The purpose of this study was to examine the influence of several root canal sealers on the discoloration of internal surface after root canal obstruction. Twenty four sound human premolars, extracted for orthodontic or prosthodontic purposes, were randomly selected and divided into eight groups. Extracted premolars were prepared, and the following seven materials were introduced into the pulp cavities: AH 26, Fuji ionomer (Type I) cement, N2, Oxypara "Murakami", Kerr sealer, PCA sealer, and G-C's Propac ZOE cement. After 7 weeks of incubation; the discolored tooth crowns were hemisectioned, and the internal staining patterns were examined. Then, with an association of observed values the mean intensity scores and percentage of coverage scores of the internal staining patterns in teeth attained by two observers using for Chisquare test were analyzed. The results were as follows: 1. All the experimental premolar's crown showed various ranged discoloration of internal surface. 2. There was no significance between the association scores of two observers participated into this experiments:% coverage scores (P > 0.05) and intensity (P > 0.05) 3. The crowns filled with PCA sealer, AH 26, and Fuji ionomer cement was visible within a depth of one third of dentin. (P> 0.05) 4. For N2, Kerr sealer, and G-C's Propac cement, A slight dentinal staining was recorded, which penetrated up to half way into the dentin. (P> 0.05) 5. It was noticed that the teeth filled with Oxypara "Murakami" were discolored more than two thirds of the dentinal layer. 6. On the control group, there was no discoloration.