• The Journal of Advanced Prosthodontics
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• v.15 no.4
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• pp.179-188
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• 2023

PURPOSE. This in vitro study aimed to evaluate the performance of digital intraoral scanners in a completely edentulous patient with angled and parallel implants. MATERIALS AND METHODS. A total of 6 implants were placed at angulations of 0°, 5°, 0°, 0°, 15°, and 0° in regions #36, #34, #32, #42, #44, and #46, respectively, in a completely edentulous mandibular polyurethane model. Then, the study model created by connecting a scan body on the implants was scanned using a model scanner, and a 3D reference model was obtained. Three different intraoral scanners were used for digital impressions (PS group, TR group, and CS group, n = 10 in each group). The distances and angles between the scan bodies in these measurement groups were measured. RESULTS. While the Primescan (PS) impression group had the highest accuracy with 38 ㎛, the values of 104 ㎛ and 171 ㎛ were obtained with Trios 4 IOSs (TR) and Carestream 3600 (CS), respectively (P = .001). The CS scanner constituted the impression group with the highest deviation in terms of accuracy. In terms of dimensional differences in the angle parameter, a statistically significant difference was revealed among the mean deviation angle values according to the scanners (P < .001). While the lowest angular deviation was obtained with the PS impression group with 0.185°, the values of 0.499° and 1.250° were obtained with TR and CS, respectively. No statistically significant difference was detected among the impression groups in terms of precision values (P > .05). CONCLUSION. A statistically significant difference was found among the three digital impression groups upon comparing the impression accuracy. Implant angulation affected the impression accuracy of the digital impression groups. The most accurate impressions in terms of both distance and angle deviation were obtained with the PS impression group.

• Korean journal of applied entomology
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• v.52 no.2
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• pp.93-100
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• 2013

In this study, the distribution of Cantao ocellatus in Korea occurred at Jindo, Tongyoung, Gwangju and Taean including Jejudo in 2012 and was coincidentally in accordance with the distribution of Mallotus japonicus as a host plant. The adult emerges in M. japonicus occur from late June to early July and can be observed until the end of October. The investigation of the female and male was measured, developmental characteristics, host plant and oviposition preference under the conditions of temperature $25^{\circ}C({\pm}2)$, humidity 65%(${\pm}2$), day length 16L:8D, by indoor breeding. For females and males respectively, average body lengths were 26.20 mm and 23.88 mm, body widths 11.35 mm and 10.57 mm, head widths 3.84 mm and 3.64 mm, probosics lengths 7.90 mm and 7.27 mm, antennal lengths 9.87 mm and 9.69 mm, anterior leg lengths 12.50 mm and 12.27 mm, intermediate leg lengths 14.61 mm and 13.12 mm, posterior leg lengths 16.90 mm and 16.53 mm, and fresh weights 0.46 g and 0.31 g. It was seen that two kinds of C. ocellatus had prickles at the end of the pronotum which had developed in the fifth instars. The female is distinguished from the male by the reproductive organ and the spotted pattern on the abdominal segment. The preference of drinks was fruit, leafstalk, midrib, and branch in Mallotus japonicus (Thunb.) Muell. Arg., Mallotus japonicus 'Variegatus', Ricinus communis L., Lonicera japonicus var. repens (Siebold) Rehder, Citrus sinensis (L.) Osbeck and Zelkova serrata (Thunb.) Makino.

• Korean Journal of Applied Biomechanics
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• v.14 no.3
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• pp.99-118
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• 2004

The aim of this study is to evaluate tennis shoes's plantar pressure distribution in tennis prayers and to determine the influence of the shoe on various tennis movements. When investigating the biomechanics of movement in tennis, one of the first things to do is to understand the movement patterns of the sport, specifically how these patterns relate to different tennis shoes. Once these patterns are understood, footwear company can design tennis shoes that match the individual needs of tennis players. Plantar pressure measurement is widely employed to study foot function, the mechanical pathogenesis for foot disease and as a diagnostic and outcome measurement tool for many performance. Measurements were taken of plantar pressure distribution across the foot and using F-Scan(Tekscan Inc.) systems respectively. The F-Scan system for dynamic in-shoe foot pressure measurements has enabled us to assess quantitatively the efficacy of different types of footwear in reducing foot pressures. The Tekscan F-Scan system consists of a flexible, 0.18mm thick sole-shape having 1260 pressure sensors, the sensor insole was trimmed to fit the subjects' right, left shoes. For this study 4 university male, high level tennis players were instructed to hit alternated forehand stroke, backhand stroke, forehand volley, backhand volley, smash, service movement in 4 different tennis shoes. 1. When impact in tennis movement, peak pressure distribution of landing foot displayed D>C>B>A, A displayed the best low pressure distribution. A style's tennis shoes will suggest prayer with high impact. If prayer with high impact feeling during pray in tennis wear A style, it will decrease injury, will have performance improvement. 2. When impact in tennis movement, plantar pattern of pressure distribution in landing foot displayed B>A>C>D in stability performance. During tennis, prayer want to stability movement suggest B style tennis shoes when tennis movement impact keep stability of human body. B style tennis shoes give performance improvement 3. When impact in tennis movement, plantar pattern of center of force(C.O.F.)trajectory in landing foot analyzed this : 1) When stroke movement and volley movement in tennis, prayer better to rearfoot movement. 2) when service movement, prayer midfoot strike movement. 3) when smash movement, prayer have forefoot strike movement.

• The Korean Journal of Nuclear Medicine
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• v.38 no.3
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• pp.259-267
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• 2004

Purpose: NEMA NU2-2001 was proposed as a new standard for performance evaluation of whole body PET scanners. in this study, system performance of Siemens CTI ECAT EXACT 47 PET scanner including spatial resolution, sensitivity, scatter fraction, and count rate performance in 2D and 3D mode was evaluated using this new standard method. Methods: ECAT EXACT 47 is a BGO crystal based PET scanner and covers an axial field of view (FOV) of 16.2 cm. Retractable septa allow 2D and 3D data acquisition. All the PET data were acquired according to the NEMA NU2-2001 protocols (coincidence window: 12 ns, energy window: $250{\sim}650$ keV). For the spatial resolution measurement, F-18 point source was placed at the center of the axial FOV((a) x=0, and y=1, (b)x=0, and y=10, (c)x=70, and y=0cm) and a position one fourth of the axial FOV from the center ((a) x=0, and y=1, (b)x=0, and y=10, (c)x=10, and y=0cm). In this case, x and y are transaxial horizontal and vertical, and z is the scanner's axial direction. Images were reconstructed using FBP with ramp filter without any post processing. To measure the system sensitivity, NEMA sensitivity phantom filled with F-18 solution and surrounded by $1{\sim}5$ aluminum sleeves were scanned at the center of transaxial FOV and 10 cm offset from the center. Attenuation free values of sensitivity wire estimated by extrapolating data to the zero wall thickness. NEMA scatter phantom with length of 70 cm was filled with F-18 or C-11solution (2D: 2,900 MBq, 3D: 407 MBq), and coincidence count rates wire measured for 7 half-lives to obtain noise equivalent count rate (MECR) and scatter fraction. We confirmed that dead time loss of the last flame were below 1%. Scatter fraction was estimated by averaging the true to background (staffer+random) ratios of last 3 frames in which the fractions of random rate art negligibly small. Results: Axial and transverse resolutions at 1cm offset from the center were 0.62 and 0.66 cm (FBP in 2D and 3D), and 0.67 and 0.69 cm (FBP in 2D and 3D). Axial, transverse radial, and transverse tangential resolutions at 10cm offset from the center were 0.72 and 0.68 cm (FBP in 2D and 3D), 0.63 and 0.66 cm (FBP in 2D and 3D), and 0.72 and 0.66 cm (FBP in 2D and 3D). Sensitivity values were 708.6 (2D), 2931.3 (3D) counts/sec/MBq at the center and 728.7 (2D, 3398.2 (3D) counts/sec/MBq at 10 cm offset from the center. Scatter fractions were 0.19 (2D) and 0.49 (3D). Peak true count rate and NECR were 64.0 kcps at 40.1 kBq/mL and 49.6 kcps at 40.1 kBq/mL in 2D and 53.7 kcps at 4.76 kBq/mL and 26.4 kcps at 4.47 kBq/mL in 3D. Conclusion: Information about the performance of CTI ECAT EXACT 47 PET scanner reported in this study will be useful for the quantitative analysis of data and determination of optimal image acquisition protocols using this widely used scanner for clinical and research purposes.

• Fashion & Textile Research Journal
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• v.13 no.4
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• pp.614-623
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• 2011

The purpose of this study is to develop a wedding dress basic torso pattern and sleeve pattern considering good fit and aesthetic for figures of Korean brides in their 20s. For the research method, 3 women in their 20s who has the body size of ${\pm}$ S.D range of average figure and dress form suggested by 'the 5th human body measurement' of Size Korea were selected as the test group. The evaluators are 8 clothing construction majors, and the evaluation items included total 22 questions related to torso and total 10 questions related to sleeves. The evaluation was made using 5 Likert point scale. 4 prototypes for basic dress pattern were selected through the literature search. After compare analyzing design methods of prototypes, the real wedding dresses were made in the average size of women in their 20s and the dresses were tried on for the assessment. The data was analyzed using SPSS 18.0 Program to examine average, standard deviation and significant differences between basic patterns. Based on the results of the first and the second try-on assessments, a new wedding dress basic pattern with maximized strengths of compared prototypes was completed. The details of result follows. As for dress torso basic pattern, A pattern, which had the highest overall silhouette satisfaction and scores in basic pattern analysis and try-on assessments, was selected as the prototype, and a research basic pattern reflecting strengths of each basic pattern was developed. As for dress sleeve basic pattern, B pattern, which had the highest overall silhouette satisfaction and scores in basic pattern analysis and try-on assessments, was selected as the prototype, and a research basic pattern reflecting strengths of each basic pattern was developed. In this study, a wedding dress basic pattern considering good fit and aesthetic for figures of Korean brides in their 20s was suggested. It is expected that the basic pattern will be used by continuously developing dress market and ready-made wedding dress manufacturers as well as in educational institutes.

• Korean Journal of Acupuncture
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• v.31 no.2
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• pp.66-78
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• 2014

Objectives : The specificity of acupuncture point has been a highly controversial subject. Existing researches said that ion-distribution differences are observed on the acupuncture point. This study was conducted under the assumption that multiple ionic changes induced by muscle fatigue would be different between the acupuncture point with non-acupuncture point. Methods : To induce the identical fatigue, twenty subjects performed the knee extension/flexion exercise using the Biodex System 3. ST32 and ST33 as well as adjacent non-acupuncture points were selected. We measured blood lactate and analyzed the median frequency(MF) and peak torque. To obtain the information on the extracellular fluid(ECW), intracellular fluid(ICW) and cell membrane indirectly, we used the multi-frequency bioelectrical impedance analysis(MF-BIA) method. Results : MF, peak torque and blood lactate level of all measurement sites were gradually returned to normal. Re resistance of ST32 had a stronger response, but a non-acupuncture point adjacent to ST33 had a larger response up to 20 minutes post exercise. Ri resistances were similar for both acupoints and non-acupoints. The $C_m$ capacitance of ST32 had a stronger response after inducing fatigue, but ST33 had a smaller response than a non-acupuncture point adjacent to it. Conclusions : In comparison with before and after inducing fatigue, the specificity of acupuncture points was not clearly observed. Hence, we concluded that the body composition factors extraction method had the limitation as a method of finding the specificity of acupuncture points by inducing fatigue.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.38 no.4
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• pp.289-296
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• 2012

Cosmetic products which might augment the breast have attracted an attention and objective methods for the evaluation of such products are in high demand. This study was conducted to establish a method for assessing the breast-firmming effects of cosmetics. This study included a total of 30 healthy Korean females aged 20-50 years. A cosmetic product was applied by massaging it onto the breast twice a day for 8 weeks. Measurement of breast girth with a tape ruler, 2D and 3D digital image analyses, and Moir$\acute{e}$ topographic analysis were performed before and following the treatment. The application of a cosmetic onto the breast significantly increased breast girth at 2, 4 and 8 weeks without a significant change in underbreast girth, implicating the breast might be augmented. The 2D image analysis indicated that the arc length of the breast which represents the surface distance from the nipple to the periphery of the under-breast was significantly increased at 2, 4 and 8 weeks. The height of the breast which represents the perpendicular distance from the nipple to the periphery of the under-breast was also increased significantly at 4 and 8 weeks. The 3D image analysis of body surface also demonstrated a significant increase of breast volume at 2, 4 and 8 weeks. Moir$\acute{e}$ topographic analysis indicated that breast sagging was significantly reduced at 2, 4 and 8 weeks. The results of this study suggest that Moir$\acute{e}$ topography in combination with 2D and 3D digital image analyses may be useful for evaluating the breast-augmenting effects of cosmetics.

• Journal of the Ergonomics Society of Korea
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• v.33 no.2
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• pp.143-153
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• 2014

Objective: The aim of this study is to investigate the effects of trunk-forearm supported sitting on trunk flexion angle, trunk extensor fatigue and seat contact pressure. Background: The relationship between sitting posture and musculoskeletal disorders of the trunk extensor fatigue and seat contact pressure has been documented. The trunk-forearm support type ergonomic chair was devised from the fact that trunk-forearm support has been reported to reduce trunk extensor activity and discomfort. Method: Using three different sitting postures, upright ($P_1$), trunk-forearm supported ($P_2$) and normal sitting ($P_3$), six healthy subjects participated in the study. Motion capture system was used to collect head and trunk flexion angle, and surface electromyography (sEMG) was used to collect myoelectric signal of upper trapezius, lower trapezius, erector spinae, multifidus, and pressure mat system was used to measure seat contact pressure. Results: When trunk and forearm were supported by the ergonomic chair, higher head flexion angle showed upright > trunk-forearm supported > normal in order, and muscle fatigue showed less than upright and normal sitting. Mean seat contact pressure decreased 19% than upright sitting. But muscle fatigue was not affected by each condition. Conclusion: Trunk-forearm supported sitting of the ergonomic chair showed positive effect in respect of trunk and head flexion angle, trunk extensor fatigue, seat contact pressure. To acquire comprehensive understanding of the effectiveness of the ergonomic chair, further studies such as anatomical effects from measurement of external applied loading effect to the body from interface pressure analysis are required. Application: The results of the publishing trend analysis might help physiological effects of trunk-forearm support type chair.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.25 no.10
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• pp.1408-1416
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• 2001

Mean flow fields in the near wake of a square cylinder have been studied experimentally using a Particle Image Velocimetry (PIV). Ensemble-averaged velocity fields are successfully measured fur the square cylinder wake including the reverse flow region which arises many difficulties in accurate measurement by using conventional techniques, Experiments are performed at two free stream velocities of U$\_$$\infty$/ = 1.27m/s and 3.03m/s. The corresponding Reynolds numbers based on the free-stream velocity and cylinder diameter are 1600 and 3900, respectively. The intensity of free-stream turbulence is less than 1%, the blockage ratio (D/H) is 6.6% and the aspect ratio (W/D) is 40. The effect of Reynolds number on the near wake of a square cylinder has been investigated by the global mean velocity and instantaneous velocity fields. The most striking feature is that the length of the recirculating region increases with increasing Reynolds number, which turns out totally reverse trend compared with those observed in the circular cylinder wake at the same range of Reynolds number. Fer the case of higher Reynolds number, the mean velocity data agree well with those of relevant existing data obtained at much higher Reynolds numbers, which reflects the general aspect of sharp-edged bluff body wake.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.306-314
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• 2002

The purpose of this study is to examine the relation between vegetarian diet and the risk factors of cardiovascular disease. The subjects of the study were 127 Buddhist nuns (age: 23 ~79 yr) for vegetarians and 235 healthy female adults (age: 23 ~79 yr) for non-vegetarians. This study covers food consumption survey, anthropometric measurement, amount of energy expenditure, physical activity and clinical examination. Average body mass index (BMI) of vegetarians and non-vegetarians were 22.47 and 21.08, waist/hip ratio (WHR) was 0.85 and 0.84, percentage of body fat (%BF) was 28.79 and 26.55, respectively. Average duration of vegetarian diet of the vegetarians was 13.16 years. The triglyceride levee of the vegetarians was significantly lower for those who take nutrient tablet compared to those who either take vitamins or who do not take any nutrient supplement. Taking vitamins or nutrient tablet did not give any significant difference in total-cholesterol and LDL-cholesterol for vegetarians, while significantly high triglyceride was observed for the non-vegetarians taking nutrient tablet than the ether non-vegetarians. Taking vitamins or nutrient tablet did not affect the lever of HDL-cholesterol for either vegetarians or non-vegetarians. Athrogenic index (AI) was lower for the vegetarian group tailing nutrient tablet and for the non-vegetarian group not taking vitamins and nutrient tablet, than the other respective groups. Blood sugar of the vegetarians who take nutrient tablet was significantly lower than those tailing vitamins, while blood sugar of the non-vegetarians not taking any nutrient supplement was significantly lower than those taking nutrient tablet.