• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.1886-1896
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• 1991

This paper presents a method to predict the flying height of the head slider in a hard disk drive. Quantitative predicts of the flying height according to the variations of the external load and the disk velocity have been done by numerical computation. In addition, the magnitude of the external load to keep flying height constant were also suggested. The Modified Reynolds' equation driven from hydrodynamic lubrication theory under slip flow condition was used to describe air-bearing system under the slider. To solve the equation, a Finite Volume Method (FVM) has been applied. To determine the final minimum flying height and pitch angle of the head slider, the Secant iteration method is used which update initial guess of the minimum flying height and pitch angle of the slider. In this study, the model head slider has been selected from a real hard disk drive which is equipped in many commercial personal computers. As a result, as the disk velocity increases at constant external load, the minimum flying height and the pitch angle increase due to the in crease of the air-bearing force at the bottom of slider.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.6
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• pp.784-790
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• 2014

In this study we aimed to evaluate the reduction in dimensionality of 20 linear type traits and more final score in 14,943 Holstein cows in Brazil using factor analysis, and indicate their relationship with longevity and 305 d first lactation milk production. Low partial correlations (-0.19 to 0.38), the medium to high Kaiser sampling mean (0.79) and the significance of the Bartlett sphericity test (p<0.001), indicated correlations between type traits and the suitability of these data for a factor analysis, after the elimination of seven traits. Two factors had autovalues greater than one. The first included width and height of posterior udder, udder texture, udder cleft, loin strength, bone quality and final score. The second included stature, top line, chest width, body depth, fore udder attachment, angularity and final score. The linear regression of the factors on several measures of longevity and 305 d milk production showed that selection considering only the first factor should lead to improvements in longevity and 305 milk production.

• Tunnel and Underground Space
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• v.23 no.2
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• pp.110-119
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• 2013

It is generalized to measure the arch settlement and convergence during tunnel construction for monitoring its mechanical stability. The initial convergence rate a day is defined from the first convergence measurement and the final convergence defined as the convergence measured lastly. The initial and the final tunnel arch settlement are defined like the preceding convergence. In the study, the relations between the initial and final displacements of a shallow tunnel are analyzed. The measurements were performed in the tunnel of subway 906 construction site in Seoul. The overburden is 10-20 m and the tunnel goes through weathered soil/rock. The width and height of the tunnel are about 11.5 m, 10m, respectively. So this is a shallow tunnel in weak rock. The length of tunnel is about 1,820 m and the tunnel was constructed in 2 stages, dividing upper and lower half. The numbers of measurement locations of arch settlement and convergence are 184 and 258, respectively. As a result, the initial displacement rate and the final displacement are comparatively larger in the section of weathered soil.

• Korean Journal of Food Science and Technology
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• v.39 no.1
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• pp.33-38
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• 2007

The peak time, peak height, width at peak, and the width at 8 min of Mixograph increased as the amount of sodium chloride in yellow alkaline noodle sheet was increased. The peak time of the Mixograph duration increased almost twice when 0.5% sodium carbonate was added to yellow alkaline noodle sheet, but decreased when the amount of sodium carbonate was above 0.5%. The peak height decreased as the amount of sodium carbonate increased. Protein content and sedimentation values showed positive correlations with the Mixograph peak height, width at peak, and width at 8min. The pasting temperature, peak viscosity, minimum viscosity, and final viscosity increased as the amount of sodium chloride in yellow alkaline noodle sheets was increased for all wheat flours. The peak viscosity, minimum viscosity, and final viscosity also increased as the amount of sodium carbonate increased. The pasting temperature showed a positive correlation with the water retention capacity and the alkaline water retention capacity.

• Journal of Genetic Medicine
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• v.10 no.2
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• pp.120-123
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• 2013

This report describes three cases of 22q11.2 deletion syndrome (22q11.2DS) diagnosed by array comparative genomic hybridization with final adult height and bone phenotype. The cases involved a 57-year-old woman with hypocalcemic seizure, an 18-year-old man with short stature, and a 24-year-old woman incidentally diagnosed as 22q11.2DS. The first two patients revealed short stature and low bone mineral density, and their deletion sites included the $TBX_1$. The third patient had normal stature and normal bone mineral density, and the deletion site did not include the $TBX_1$. The deletion of specific genes including the $TBX_1$ could be an important factor of skeletal development including height and bone mineral density of 22q11.2DS.

• Physical Therapy Rehabilitation Science
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• v.3 no.2
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• pp.86-92
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• 2014

Objective: Whole body vibration (WBV) and plyometrics are common training techniques which increase strength, blood flow, and lower body force and power. The effects these techniques have on sedentary population is unknown. It is our aim to assess the effectiveness of WBV and plyometrics on sedentary population. Design: Experimental study. Methods: Twenty-seven sedentary subjects were assigned to either the control group, jumping only group, or jumping with vibration group. Jump height (myotest or vertec), velocity, force, blood lactates, and rating of perceived exertion (RPE). Subjects were measured on the initial, seventh, and eighteenth visits. Control group attended measurements only. Jumping only and jumping with vibration groups performed jumping from a vibrating platform to a surface 7 1/2 inches higher for 3 bouts of 20 seconds. Each subject in jumping only and jumping with vibration groups attended three times per week for six weeks. Vibration was set at 40 Hz and 2-4 mm of displacement. Results: There was no significant change among groups in force, velocity, vertec height, and myotest height. However there was a significant increase in vertec height from initial to final measure (p<0.05) for jumping with vibration group. RPE was significantly higher between control group and jumping with vibration group after intervention (p<0.05). Conclusions: WBV with vibration increased jump height. Jumping with vibration group experienced increased exertion than for controls. WBV with plyometrics had no effect on force, velocity, blood lactates, or calculated jump height. Further studies controlling for initial measure of blood lactates and using an external focus may be necessary to elicit velocity, force and jump height changes.

• Clinical and Experimental Pediatrics
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• v.50 no.1
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• pp.65-73
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• 2007

Purpose : Short stature is an important complication that impairs the quality of life in survivors of childhood brain tumors. We studied their final adult height (FAH) to evaluate risk factors for short stature. Methods : We reviewed the medical data of 95 survivors of childhood brain tumors (64 males and 31 females) who had been followed up from 1982 to 2006, reached FAH, and had a more than five year-disease-free survival. Results : Final adult height standard deviation score (FAHTSDS: $mean{\pm}SD$) of the patients was lower than those of general population ($-1.15{\pm}1.72$), HTSDS at diagnosis ($-0.13{\pm}1.57$), and target HTSDS ($-0.49{\pm}0.69$). FAHTSDS of craniopharyngioma patients did not decrease ($0.57{\pm}1.17$), but those of germ cell tumor and medulloblastoma patients were significantly reduced ($-1.20{\pm}1.45$, $-2.70{\pm}1.46$; P<0.05). The patients treated with craniospinal radiation or chemotherapy had lower FAHTSDS ($-1.93{\pm}1.58$, $-2.27{\pm}1.44$; P<0.01). In the spinal irradiation group, the younger the age at diagnosis was, the more the loss of FAH (r=0.442, P<0.01). Growth hormone replacement (GHR) didn't improve FAHTSDS, but starting GHR under 12 years was an independent factor for improving FAH once treatment methods were taken into account (P=0.01). Conclusion : The younger age at diagnosis, spinal radiation and chemotherapy were all important risk factors of height loss, and height gain was expected in patients who received GHR under the age of 12 years. Therefore, regular check-ups of growth and early intervention with growth hormones are needed for high risk groups to improve FAH.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.121-134
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• 2004

This article describes a clinical protocol for the conventional rehabilitation of patient diagnosed with partial anodontia. A combined dental therapy approach was used and included endodontic therapy and root capping on the maxillary central incisors, fabrication of a maxillary overdenture, and fabrication of mandibular konus overdenture supported by 3 konus abutments. Within this protocol, tooth-supported overdenture prostheses are used for 2 purposes: first, to obtain the most rigid retention and function at an established maxillary-mandibular relationship; and second, to continuously maintain function and esthetic appearance applying immediate dentures after teeth extraction. The idea behind this protocol and its associated clinical procedures is presented along with a discussion compared with implant therapy. In the case introduced, and after 7 years of observation, the therapy can be seen as a success. We increased the occlusal vertical height in this case, but it would be more appropriate to see this as recovering the occlusal vertical height that was lost. The process of increasing the occlusal vertical height, that is restoration of the face, modification of the extrinsic occlusion of the incisors, and retraction of the mandible is very difficult and important. Ultimately, class III malocclusion is fixed, adequate occlusal vertical height is gained, and the retracted posterior anodontial portion is restored by prosthodontic dentures based on the rigid support theory. The result of the therapy done on the later-achieved malocclusion with partial anodontia on the posterior portion must consider the following in order to maintain the safety of the esthetics of the tooth and face for a period of time: 1) occlusal restoration with an ideal occlusal vertical height, 2) allowance of the final occlusion induced by the functional relationship of the upper and lower jaw, 3)final occlusion functionally induced by the lip competence limit.

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.191-196
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• 2005

Purpose : Short stature is one of the characteristic features of Turner syndrome. We investigated the factors affecting final adult height(FAH) in patients with Turner syndrome. Methods : The study group was comprised of 60 patients who were diagnosed with Turner syndrome by chromosomal study and clinical phenotypes and attained FAH. Data were obtained from retrospective review of the medical records. We analyzed the factors influencing FAH in growth hormone(GH) treated and GH untreated groups. Results : Sixty patients were enrolled; 48 patients received GH treatment, and 12 patients did not. Mean duration of GH treatment was 35.8 months(range 4 to 120 months), and mean dosage of GH was $0.8{\pm}0.2IU/kg/wk$ in GH treated group. Mean growth velocity was $5.6{\pm}2.0cm/yr$, which was significantly higher than that during pretreatment period. In the GH treated group, mean chronological age, bone age, mean height, and height standard deviation(SD) score at GH treatment were $12.2{\pm}2.7yr$ $10.3{\pm}2.5yr$ $127.5{\pm}10.1cm$ and $-3.1{\pm}1.1$, respectively. In the GH treated group, the mean FAH and SD score of FAH were $146.9{\pm}5.8cm$ and $-2.7{\pm}1.2$, respectively, which showed significant differences compared with those of the GH untreated group. Analyzing the factors affecting FAH in GH-treated patients, only the SD score of height at the time of treatment was significantly related to FAH. Conclusion : GH treatment leads to an increment in FAH in patients with Turner syndrome. Average FAH gain was as much as 5.8 cm. SD score of height at the time of GH treatment was the only factor influencing FAH.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.11
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• pp.91-97
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• 1995

In this study, a deformation model for the regular polygonal-shaped tubes from hollow-cylindrical billets is proposed and a kinematically admissible velocity field is obtained from this deformation model. The final stage upper-bound extrusion load and the average extruded length are determined by minimizing the total power consumption with respect to chosen parameters. Experiments have been carried out with hard solder billets at room temperature. The theoretical predictions of the extrusion load are in good agreements with the experimental results and there is generally reasonable agreement in average extruded height between theory and experiment.