• Title/Summary/Keyword: statistical inferences

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Evaluation of internal adaptation of dental adhesive restorations using micro-CT

  • Kwon, Oh-Hyun;Park, Sung-Ho
    • Restorative Dentistry and Endodontics
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    • v.37 no.1
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    • pp.41-49
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    • 2012
  • Objectives: The internal adaptation of composite restorations with or without resin modified glass ionomer cement (RMGIC) was analyzed non-destructively using Microcomputed tomography (micro-CT). Materials and Methods: Thirty intact human teeth were used. The specimens were divided into 3 groups. In the control group, the cavities were etched with 10% phosphoric acid for 15 sec. Composite resin was filled into the cavity without adhesive. In group 1, light cured glass ionomer cement (GIC, Fuji II LC, GC) was applied as a base. The cavities were then etched, bonded, light cured and filled with composites. In group 2, the cavities were then etched, bonded, light cured and filled with composites without base application. They were immersed in a 25% silver nitrate solution. Micro-CT was performed before and after mechanical loading. One-way ANOVA with Duncan analysis was used to compare the internal adaptation between the groups before or after loading. A paired t-test was used to compare internal adaptation before and after mechanical loading. All statistical inferences were made within the 95% confidence interval. Results: The silver nitrate solution successfully penetrated into the dentinal tubules from the pulp spaces, and infiltrated into the gap between restoration and pulpal floor. Group 2 showed a lower adaptation than the control group and group 1 (p < 0.05). There was no significant difference between the control group and group 1. For all groups, there was a significant difference between before and after mechanical loading (p < 0.05). Conclusions: The internal adaptation before and after loading was better when composites were bonded to tooth using adhesive than composites based with RMGIC.

Study and Evaluation of Tourism Websites based on User Perspective

  • Shrestha, Deepanjal;Wenan, Tan;Rajkarnikar, Neesha;Shrestha, Deepmala;Jeong, Seung Ryul
    • Journal of Internet Computing and Services
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    • v.22 no.4
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    • pp.65-82
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    • 2021
  • A well-designed website is mandatory for good marketing and proper tourism business. This research considers Nepal as a domain of study and specifically explores welcomenepal.com, the official tourism portal as a reference for the study. The work is based on the study of the existing literature, user-survey, and technical testing of the website using open-source testing tools to identify user perspective, design issues, website architecture and design quality of the tourism website. A population size of 400 respondents, which consist of both domestic and international tourist, are considered for the survey. Data is received from 360 respondents, which is analyzed using statistical tests like Cronbach's alpha, Pearson's correlation, cross-tabulations, bars charts and graphs to draw inferences and consclusion. The software-based test results serve as another important parameter for the evaluation of the current official website. This study brings out core needs of the tourist in terms of expectations from a tourism website and access technical quality of the current portal to provide necessary feedback and suggestions. The government officials, business houses, and web designers can utilize this work as a knowledge base to build tourism websites, which are user-centric. Further, the work is specifically important for Nepal government and tourism officials to identify shortcomings in their current website and make improvements for better design and user adaptability in future.

A Strategy for Inference Control of Official Statistics - Centering around the Patent Application Expense Support Project - (공식통계의 추론통제 전략 - 정부의 특허경비지원사업 사례를 중심으로 -)

  • Lee, Duck-Sung;Choi, In-Soo
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.11
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    • pp.199-211
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    • 2009
  • Official statistics which are collected for governments and the community can be used to assess the effectiveness of governments' policies and programs. Thus, official statistics should be collected and presented based on correct findings. Erroneous official statistics will lead to lower quality results in assessing those policies and programs. Many statistical agencies, today, use on-line analytical processing (OLAP) data cubes which support OLAP tasks like aggregation and subtotals as a key part of their dissemination strategy of official statistics. Confidentiality protection in data cubes also should be made. However, sensitive parts of data cubes including micro data may be disclosed by malicious inferences. The authors have suggested an inference control process in OLAP data cubes which preventing erroneous cube creating and securing cubes against privacy breaches. The objective of this study is to establish a strategy for inference control of official statistics using the inference control process by taking the case of the Patent Application Expense Support Project.

Real-time Fault Detection System of a Pneumatic Cylinder Via Deep-learning Model Considering Time-variant Characteristic of Sensor Data (센서 데이터의 시계열 특성을 고려한 딥러닝 모델 기반의 공압 실린더 고장 감지 시스템 구현)

  • Byeong Su Kim;Geun Myeong Song;Min Jeong Lee;Sujeong Baek
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.47 no.2
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    • pp.10-20
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    • 2024
  • In recent automated manufacturing systems, compressed air-based pneumatic cylinders have been widely used for basic perpetration including picking up and moving a target object. They are relatively categorized as small machines, but many linear or rotary cylinders play an important role in discrete manufacturing systems. Therefore, sudden operation stop or interruption due to a fault occurrence in pneumatic cylinders leads to a decrease in repair costs and production and even threatens the safety of workers. In this regard, this study proposed a fault detection technique by developing a time-variant deep learning model from multivariate sensor data analysis for estimating a current health state as four levels. In addition, it aims to establish a real-time fault detection system that allows workers to immediately identify and manage the cylinder's status in either an actual shop floor or a remote management situation. To validate and verify the performance of the proposed system, we collected multivariate sensor signals from a rotary cylinder and it was successful in detecting the health state of the pneumatic cylinder with four severity levels. Furthermore, the optimal sensor location and signal type were analyzed through statistical inferences.

IN VITRO MARGINAL FIT OF THE COMPUTERAIDED MILLED CERCON CROWNS

  • Chang, Jae-Yoon;Yang, Jae-Ho;Han, Jung-Suk;Lee, Jai-Bong
    • The Journal of Korean Academy of Prosthodontics
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    • v.43 no.3
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    • pp.306-313
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    • 2005
  • Statement of problem. There have been many studies about marginal discrepancy of single restorations made by various systems and materials. But most of statistical inferences are not definite because of sample size, measurement number, measuring , instruments, etc. And there have been few studies about the marginal fit of Computer-aided Cercon crowns. Purpose. The purpose of this study was to compare the marginal fit of the anterior single restorations made using computer-aided milled Cercon crowns with metal-ceramic restorations and to obtain more accurate information by using a large enough sample size and by making sufficient measurements per specimen. Material and methods. The in vitro marginal discrepancies of computer-aided milled Cercon crowns and control groups (metal ceramic crowns) were evaluated and compared. The crowns were made from one extracted maxillary central incisor prepared by milling machine. 30 crowns per each system were fabricated. Measurements of a crown were recorded at 50 points that were randomly selected for marginal gap evaluation. Parametric statistical analysis was performed for the results. Results. The means and standard deviations of the marginal fit were 85$\pm$22$\mu$m for the control group and 91$\pm$15$\mu$m for the Cercon crowns. The t-test of the marginal discrepancies between Cercon crowns and metal-ceramic crowns were performed. Significant differences were not found between groups (P=0.230>.05). Based on the criterion of 120$\mu$m as the limit of clinical acceptability, the mean marginal fits of Cercon crowns and metal-ceramic crowns were acceptable. Conclusion. Within the limitations of this in vitro study, the following conclusions were drawn: 1. Mean gap dimensions and standard deviations at the marginal opening for maxillary incisal crowns were 85$\pm$22$\mu$m for the control (metal-ceramic crowns), 91$\pm$15$\mu$m for Cercon crowns. 2. The Cercon crowns showed slightly larger marginal gap discrepancy than the control but marginal gap between Computer-aided milled Cercon crowns and metal ceramic crowns did not showed significant difference (P>.05). 3. The Cercon crowns and metal ceramic crowns showed clinically acceptable marginal discrepancy.

The Effect of the Adjustment Stress and the Social Support on the Depressive Symptoms of the North Korean Defectors (탈북자의 적응스트레스와 사회적 지지가 우울성향에 미치는 영향)

  • Kim, Mee-Ryoung
    • Korean Journal of Social Welfare
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    • v.57 no.1
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    • pp.193-217
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    • 2005
  • Due to the increasing concerns with the North Korean defectors, the researches have been increased. When it is compared with other areas, the researches about the North Korean defectors are rare. The sample size of this study is 164, which makes it possible to do statistical inferences. As statistical methods, t-test, ANOVA and hierarchical multiple regressions are used. This study examines the effect of the adjustment stress and the social support on the depressive symptoms. Demographic factors such as gender, age and education are controlled. The context factors-the period of the stay in the third place, the period of residence and the existence of the education in Korea- are used as control variables. The research results show that the level of social participation of the women is higher than that of men. Also, there are differences of the functional social support by the age group. The research result indicates the education of South Korea is an important factor to reduce the depressive symptoms. The research result also shows that the jobless is an important stressor. Among structural social support, the member of religious or social group is an important factor for reducing depressive symptoms. Among functional social support, the emotional social support is an important factor of adaptation, but the effect of instrumental social support is the opposite. Therefore, the adequacy of social support in a specific situation must be considered.

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Anesthetic efficacy of primary and supplemental buccal/lingual infiltration in patients with irreversible pulpitis in human mandibular molars: a systematic review and meta-analysis

  • Gupta, Alpa;Sahai, Aarushi;Aggarwal, Vivek;Mehta, Namrata;Abraham, Dax;Jala, Sucheta;Singh, Arundeep
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.21 no.4
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    • pp.283-309
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    • 2021
  • Achieving profound anesthesia in mandibular molars with irreversible pulpitis is a tedious task. This review aimed at evaluating the success of buccal/lingual infiltrations administered with a primary inferior alveolar nerve block (IANB) injection or as a supplemental injection after the failure of the primary injection in symptomatic and asymptomatic patients with irreversible pulpitis in human mandibular molars. The review question was "What will be the success of primary and supplemental infiltration injection in the endodontic treatment of patients with irreversible pulpitis in human mandibular molars?" We searched electronic databases, including Pubmed, Scopus, and Ebsco host and we did a comprehensive manual search. The review protocol was framed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist. We included clinical studies that evaluated and compared the anesthetic outcomes of primary IANB with primary and/or supplementary infiltration injections. Standard evaluation of the included studies was performed and suitable data and inferences were assessed. Twenty-six studies were included, of which 13 were selected for the meta-analysis. In the forest plot representation of the studies evaluating infiltrations, the combined risk ratio (RR) was 1.88 (95% CI: 1.49, 2.37), in favor of the secondary infiltrations with a statistical heterogeneity of 77%. The forest plot analysis for studies comparing primary IANB + infiltration versus primary IANB alone showed a low heterogeneity (0%). The included studies had similar RRs and the combined RR was 1.84 (95% CI: 1.44, 2.34). These findings suggest that supplemental infiltrations given along with a primary IANB provide a better success rate. L'Abbe plots were generated to measure the statistical heterogeneity among the studies. Trial sequential analysis suggested that the number of patients included in the analysis was adequate. Based on the qualitative and quantitative analyses, we concluded that the infiltration technique, either as a primary injection or as a supplementary injection, given after the failure of primary IANB, increases the overall anesthetic efficacy.

Estimation of Genetic Parameters for Gestation Length, Wean to First Service, Litter Size and Stillborn Piglets in a Closed Nucleus Swine Breeding Herd (특정 종돈집단의 임신기간, 이유후초종부일, 총산자수 및 사산에 대한 유전모수 추정)

  • Lee, Deukhwan;Son, Jihyun
    • Journal of Animal Science and Technology
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    • v.55 no.5
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    • pp.389-398
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    • 2013
  • This study was conducted to investigate the genetic relationships among four reproductive traits. Data for this study were 7616 records from 1910 Landrace (L) and 10,454 records from 2283 Yorkshire (Y) in a closed nucleus swine herd. Traits considered on this study were gestation length (GL), total number of piglets born (TNB), wean to first service (WFS), and number of stillborn per litter (NSB). Heritabilities and genetic correlations were estimated by using the Bayesian inferences via Gibbs sampling in a four trait linear-threshold repeatability animal mixed model by designating NSB as a categorical trait in the L and Y purebred populations. Effects on the statistical model were considered for parity, contemporary group as fixed and service sire, permanent environmental, animal additive genetic effects as random. Estimates of heritability were 0.21, 0.23, 0.16, and 0.09 for GL, WFS, TNB, and NSB in the L population and 0.35, 0.16, 0.14 and 0.10 for corresponding traits in the Y population, respectively. Genetic correlation for GL was -0.59 and -0.28 with TNB and -0.58 and -0.17 with NSB in the L and Y populations, respectively. The NSB was positively correlated with TNB in the L and Y populations in genetic and environmental aspects. Therefore, the NSB should be taken into account in selecting sows for improving prolificacy of dam line breeding swine stock.

On the Tuna Schools Associated with the Drift Objects or Animals in the Western Equatorial Pacific Waters (태평양 서부 적도해역에서 부류물체나 동물과 함께 발견된 다랑어 어군에 관하여)

  • PARK Sing-Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.1
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    • pp.47-54
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    • 1984
  • From the four tuna purse seiners operating in the western equatorial Pacific waters 370 tuna schools were sampled on attribute of the school, fishing operation of purse seine sit and catch. The data were tabulated and subjected to the statistical tests of independency on the associated object and availability of the school, and catch per set of purse seine fishery as well. The resultant inferences are as follows. 1. Most frequent attributes of the tuna schools found on the surface are associated with sea birds, bait fishes and the flotsams. 2. In fishing operations of purse seine sets on the flotsam-associated schools, the settings were more frequently performed at dawn than in day-time. In fishing operations on the sea-birds-associated schools, the siftings were more frequent in day-time than at dawn. 3. From the flotsam-associated schools the successful sets were significantly more frequent. 4. In the fishing operations of purse seine sets, some of the flotsam-associated schools were subjected to the supplementary sets in success to the initial sets until the schools were consummated. 5. The fish-attracting effect of the flotsam is correlated with structure of the flotsam, but not with length of the flotsam. The flotsams, which tend to attract large tuna schools are the complicated-structure flotsams, i, e. driftwoods with roots or branches or with both of them, otherwise a bunch of uprooted bamboo shrubs, while a log without roots and branches tend to be an attractant inferior to the flotsam of complicated structure.

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Comparative study on production, reproduction and functional traits between Fleckvieh and Braunvieh cattle

  • Cziszter, Ludovic-Toma;Ilie, Daniela-Elena;Neamt, Radu-Ionel;Neciu, Florin-Cristian;Saplacan, Silviu-Ilie;Gavojdian, Dinu
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.5
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    • pp.666-671
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    • 2017
  • Objective: Aim of the current comparative study was to evaluate production outputs, reproduction efficiency and functional traits in dual-purpose Fleckvieh and Braunvieh cows, reared under temperate European conditions. Methods: A data-set from 414 Fleckvieh and 42 Braunvieh cows and 799 lactations was analysed. ID tag number, milk yield per milking session, number of steps/interval and milk conductivity were recorded and collected daily using AfiMilk 3.076 A-DU software (Afimilk Ltd., Kibbutz, Israel). Production and milk quality data were taken from the results of the official performance recordings and the reproductive outputs of cows were recorded by the research stations veterinarians. Comparisons between the two genotypes were carried out using the one way analysis of variance protocol, with categorical factor being considered the breed of cows. All the statistical inferences were carried out using Statistica software (StatSoft Inc., Tulsa, OK, USA). Results: Fleckvieh cows significantly outperformed ($p{\leq}0.05$) the Braunvieh herd, with average milk yields of $5,252.1{\pm}35.79kg$ and $4,897.6{\pm}128.94kg$, respectively. Age at first calving was significantly ($p{\leq}0.01$) influenced by the breed, with Fleckvieh heifers being more precocious ($32.8{\pm}0.29mo$) compared to those of Braunvieh breed ($35.7{\pm}0.84mo$). Reproduction efficiency as defined by the number of inseminations per gestation, calving interval, dystocia, days dry and days open, was not influenced by genotype (p>0.05). Incidences of sub-clinical mastitis, clinical mastitis, lameness and abortions were not influenced by the breed factor (p>0.05). Stay-ability of cows was significantly ($p{\leq}0.001$) influenced by genotype, with Braunvieh cows having an average age at culling of $117.88{\pm}11.78$ months compared to $90.88{\pm}2.89$ months in Fleckvieh. Conclusion: Overall, results have shown that genotype significantly influenced milk yield, age at first calving and longevity.