• Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.337-348
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• 2016

An experimental approach is presented for the measurement of wear that is common in the threading of cold-forged steel. In this work, the first objective is to measure wear on various types of roll taps manufactured to tapping holes in microalloyed HR45 steel. Different geometries and levels of wear are tested and measured. Taking their geometry as the critical factor, the types of forming tap with the least wear and the best performance are identified. Abrasive wear was observed on the forming lobes. A higher number of lobes in the chamber zone and around the nominal diameter meant a more uniform load distribution and a more gradual forming process. A second objective is to identify the most accurate data-mining technique for the prediction of form-tap wear. Different data-mining techniques are tested to select the most accurate one: from standard versions such as Multilayer Perceptrons, Support Vector Machines and Regression Trees to the most recent ones such as Rotation Forest ensembles and Iterated Bagging ensembles. The best results were obtained with ensembles of Rotation Forest with unpruned Regression Trees as base regressors that reduced the RMS error of the best-tested baseline technique for the lower length output by 33%, and Additive Regression with unpruned M5P as base regressors that reduced the RMS errors of the linear fit for the upper and total lengths by 25% and 39%, respectively. However, the lower length was statistically more difficult to model in Additive Regression than in Rotation Forest. Rotation Forest with unpruned Regression Trees as base regressors therefore appeared to be the most suitable regressor for the modeling of this industrial problem.

• The Journal of Korean Academy of Prosthodontics
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• v.43 no.6
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• pp.745-750
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• 2005

Statement of problem. Resonance frequency analysis has been increasingly served as a non-invasive and objective method for clinical monitoring of implant stability. Many clinical studies must be required for standardized data using RFA. Purpose. This study was performed to evaluate RFA value changes in two anodized implant groups. Material and method. Among a total of 24 implants, twelve screw shaped implants as a test group (H2-R8.5) were manufactured, which had a pitch-height of 0.4 mm, an outer diameter of 4.3 mm, a length of 8.5 mm, and external hexa-headed, were turned from 5 mm rods of commercially pure titanium (ASTM Grade IV, Warantec Co., Seoul, Korea), and another twelve implants as a control group were $Br{\aa}nemark$ Ti-Unite MK4 (diameter 4.0 mm, length 8.5 mm). Each group was installed in tibia of rabbit. Two implants were placed in each tibia (four implants per rabbit). Test two implants were inserted in right side and control two in left side. ISQ values were measured using $Osstell^{TM}$ (Integration Diagnostics Ltd. Sweden) during fixture installation, and 12 weeks later and evaluated the RFA changes. Results. Mean and SD of baseline ISQ values of test group were $75.0{\pm}3.4$ and $68.7{\pm}8.1$ for control group. Mean and SO of ISQ values 12 weeks after implant insertion were $73.2{\pm}4.7$ for test group and $72.6{\pm}3.9$ for control group. There were no statistically significant differences between groups in ISQ values after 3 months (P>0.05). From the data, RFA gains after 3 months were calculated, and there was statistically significant difference between groups (P<0.05). Conclusion. Although there were RFA changes between groups, implant stability after experimental period shows alike tendency and good bone responses.

• Korean Journal of Community Nutrition
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• v.10 no.5
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• pp.645-653
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• 2005

The prevalence of undernutrition in hospital populations is known to be high. The presence of malnutrition is associated with depression, infections, sarcopaenia, falls, fractures, reduced autonomy and increased mortality. This study specifically examined the prevalence of malnutrition in patients aged 65 or older at the time of admission as determined by the Mini Nutritional Assessment (MNA) which has been a frequently used nutritional risk screening tools in detecting undernutrition in old people. This study was done for one hundred eight hospitalized geriatric patients in Seoul National University Bundang Hospital, Seoul, Korea. On admission baseline history, anthropometrics measurements, laboratory data and nutritional status by MNA were assessed. Length of hospital stay was obtained by reviewing medical charts. We used one-way analysis of variance to compare the differences in variables. Spearman's rank correlation coefficients were calculated for associations between MNA and variables. On admission, $22.3\%$ of patients were malnourished and $40.7\%$ were at risk of malnutrition according to the MNA. Percent of ideal body weight, anthropometrics data, albumin, and hemoglobin were lower in the malnourished patients (p<0.05). The malnourished patients stayed in the hospital 7.3 days longer, as compared with well nourished patients (p<0.05). Percent of ideal body weight, albumin, hemoglobin and total cholesterol were correlated inversely with nutritional status according to MNA (p<0.05). MNA can be used for nutritional assessment in Korean old people, because MNA significantly correlated with other nutritional assessment parameters, such as, anthropometric and laboratory data in hospitalized geriatric patients. The high prevalence of malnutrition in the elderly was observed and the presence of malnutrition on admission predicted a significant increase in the length of hospital stay in this study. Therefore further studies are needed to determine whether nutritional interventions in old people with low MNA scores can improve clinical outcomes during the hospital course.

• Journal of Welding and Joining
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• v.34 no.1
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• pp.54-58
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• 2016

In this research paper, suggest method of generate same bead as an actual measurement data in virtual welding conditions, exploit morphology information of the bead that acquired through robot welding. It has many multiple risk factors to Beginners welding training, by we make possible to train welding in virtual reality, we can reduce welding training risk and welding material to exploit bead visualization algorithm that we suggest so it will be expected to achieve educational, environmental and economical effect. The proposed method is acquire data to each case performing robot welding by set the voltage, current, working angle, process angle, speed and arc length of welding condition value. As Welding condition value is most important thing in decide bead form, we would selected one of baseline each item and then acquired metal followed another factors change. Welding type is FCAW, SMAW and TIG. When welding trainee perform the training, it's difficult to save all of changed information into database likewise working angle, process angle, speed and arc length. So not saving data into database are applying the method to infer the form of bead using a neural network algorithm. The way of bead's visualization is applying the spline algorithm. To accurately represent Morphological information of the bead, requires much of morphological information, so it can occur problem to save into database that is why we using the spline algorithm. By applying the spline algorithm, it can make simplified data and generate accurate bead shape. Through the research paper, the shape of bead generated by the virtual reality was able to improve the accuracy when compared using the form of bead generated by the robot welding to using the morphological information of the bead generated through the robot welding. By express the accurate shape of bead and so can reduce the difference of the actual welding training and virtual welding, it was confirmed that it can be performed safety and high effective virtual welding education.

• Journal of Biosystems Engineering
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• v.26 no.6
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• pp.571-578
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• 2001

Production of green pepper has increased for ten years in Korea, as customer's preference of a pepper tuned to fiesta one. This study was conducted to develop an on-line fading algorithm of green pepper using machine vision and aimed to develop the automatic on-line grading and sorting system. The machine vision system was composed of a professive scan R7B CCD camera, a frame grabber and sets of 3-wave fluorescent lamps. The length and curvature, which were main quality factors of a green pepper were measured while removing the stem region. The first derivative of the thickness profile was used to remove the stem area of the segmented image of the pepper. A new boundary was generated after the stem was removed and a baseline of a pepper which was used for the curvature determination was also generated. The developed algorithm showed that the accuracy of the size measurement was 86.6% and the accuracy of the bent was 91.9%. Processing time spent far grading was around 0.17 sec per pepper.

• Journal of Home Health Care Nursing
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• v.10 no.2
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• pp.123-131
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• 2003

This study was to compare the functional status. complication and readmission rates. and client satisfaction with nursing care of home-based care and hospital-based care for clients with Coronary Artery Bypass Graft. Raw data were collected by interviewing and reviewing charts of 41 clients with Coronary Artery Bypass Graft between June 2001 and July 2002 at an university hospital located in Seoul. Korea. Out of 41 clients. 15 were in home care group and 26 were in hospitalization group. The baseline characteristics of the groups were almost identical. Mean age was 61.7 and 75.6% of clients being male. For home care group. the data collection was made at discharge and at termination of home care. and for hospitalization group. at discharge and at the first visit of outpatient department. Complication and readmission rates were investigated at one month after operation. Collected data were then analysed by conducting Chi-square test. Wilcoxon rank sum test. and Wilcoxon signed ranks test with SPSS program. The level of significance was .05. The results of the study are summarized as follows: 1. Postoperative length of stay of the home care group was shorter than that of hospitalization group by 1. 14 days(8.45 days vs. 9.59 days). On average. 1.8 home visits per client were observed. 2. The functional status (Barthel Index) at the termination of home care was significantly increased from that at discharge. For hospitalization group. a significant increase was observed between the functional status at the discharge and that at the first visit of outpatient department. The differencies in incremental of the scores. between the groups. were however not significant. 3. Complication and readmission rates; no statistically significant difference between the groups was observed. 4. The client satisfaction with nursing care (CSS) at termination of home care was significantly higher than that at hospital discharge. In conclusion. the outcomes of the analysis suggest that the home care benefits clients with Coronary Artery Bypass Graft. Client satisfaction with nursing care rises at termination of home care as compare to that measured at hospital discharge. Meanwhile. there was no significant differences in functional status. and complication and readmission rates. Further. home care reduced the length of stay in hospital.

• Journal of the Korea Convergence Society
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• v.9 no.10
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• pp.109-120
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• 2018

The purpose of this study was to investigate the effects of functional electrical stimulation (FES) with mirror therapy on balance and gait ability in chronic stroke patients. Thirty-five subjects who met the inclusion criteria were randomly allocated into three groups: the functional electrical stimulation with mirror therapy group(FMT group, n=11), mirror therapy group(MT group, n=12), and control group (n=12). The exercises were conducted for 30 min per day, five, per week for four weeks. Balance and gait ability were examined at baseline and after 4 weeks of intervention. After training, the FMT group showed significant improvement in berg balance scale (BBS), center of pressure (COP) length, affected step length (ASL), Cadence and average gait speed (AGS) compared MT group and control group(p<0.05). This findings show that FES and MT convergence can be an effective intervention for stroke patients balance and gait ability. Continued development of convergence interventions for stroke patients with balance and gait ability in practice, are suggested.

• Clinics in Shoulder and Elbow
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• v.1 no.2
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• pp.250-255
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• 1998

Purpose of the study was to analyze the supraspinatus outlet image of sagittal MRI in rotator cuff disease. We analyzed the sagittal views of the shoulder MRI of 78 cases without cuff tear. The cases were divided into 51 cases of rotator cuff disease group and 27 cases of control group. Six parameters of acromial tilt, coracoacromial ligament angle, length and height of coracoacromial triangle, length of acromial side of the baseline and distance of intrusion of the humeral head were compared for each group. The distance of intrusion of the humeral head was the most significantly different one, 0.52cm for rotator cuff disease group and 0.15cm for control group. Intrusion of the humeral head to the supraspinatus outlet space from the bottom may be a contributing factor developing rotator cuff disease. The intrusion may precede to tearing of the rotator cuff.

• Journal of Periodontal and Implant Science
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• v.38 no.3
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• pp.521-528
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• 2008

Purpose: Tunneling is a periodontal surgical procedure that creates access for patient cleansing and maintenance within the furcal area of a molar tooth with severe furcation involvement. Up to date, there are few studies about a long term clinical and radiographic stability of tunneling. The purpose of this retrospective study is to evaluate the long term prognosis after tunnel preparation of molars with through and through furcation. Material and Methods: 25 teeth of 23 patients aged 36 to 70 (mean age 51.7) were treated surgically with tunnel preparation. These cases were followed for 2 to 13 years (mean 6.5years) after surgery. Patients were recalled for an evaluation which was based on a questionnaire, a clinical examination, and radiographic analysis. Clinical assessment included plaque index, caries registration, probing pocket depth, bleeding on probing, tooth mobility. Baseline and over 2-year follow-up radiographs were collected and evaluated for this study. Result: 3 teeth(12%) had been extracted and 1 tooth(4%) hemisected. Root caries was detected in 3 teeth(12%). Thus 72% of the teeth were still caries tree and in function. Clinical parameters including PI, PD, BOP, mobility showed somewhat favourable results. Radiographic furcal bone loss showed no statistically significant difference compared to interproximal crestal bone loss ($3.59{\pm}1.69%$ vs $3.42{\pm}2.95%$) when root length was used as reference. There was no correlation between root trunk length and furcal bone loss. Conclusion: Over 2 years after tunneling procedure, teeth showed a clinically and radiographically stable condition, despite of slight root caries and alveolar bone loss within clinically acceptable range. The tunnel procedure may be considered as a viable periodontal treatment option for molar teeth with severe furcation involvement in individuals following a regular maintenance program.

• Fisheries and Aquatic Sciences
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• v.25 no.7
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• pp.380-389
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• 2022

Morphometric relationships, condition factor (CF) and reproductive biology are significant tools in fish stock management, fish biology, physiology, conservation and ecology. Growth and reproductive strategy of Oreochromis niloticus were studied from 343 fish specimens collected from Lake Shala between January and December 2018. Fish samples ranged from 7.7 cm to 33.0 cm in total length (TL) and from 7.80 g to 708.21 g in total weight (TW) were collected using gillnets of 4, 6, 8, 10, and 12 mm mesh sizes. The length-weight relationship of O. niloticus was TW = 0.0104TL^3.19, indicating positive allometric growth of the fish. The sex ratio (0.93:1) was insignificant from the ideal fish distribution of 1:1 (χ² = 0.47, p > 0.05). Mean CF for males, females and combined sexes was 1.04, 1.06 and 1.05, respectively and statistically insignificant (p > 0.05). The spawning peak occurred in July (rainy) and February (dry) periods, as defined by ripe females and the breeding season. Absolute mean fecundity was 806 eggs and correlated positively with TL and TW of the fish (p < 0.05) (F = 0.56TL^2.29, R² = 0.93, p < 0.05; F = 18.83TW^0.67, R² = 0.90, p < 0.05). The study provides the first detailed account of the morphometric relationships and reproductive biology of O. niloticus in Lake Shala, which can be used as baseline information for successive biological-based studies in Soda Lakes of Ethiopia.