• International Journal of Fluid Machinery and Systems
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• v.10 no.2
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• pp.154-163
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• 2017

Performance characteristics in pump mode of pump-turbines are vital for the safe and effective operation of pumped storage power plants. However, the head characteristics are different under different guide vane openings. In this paper, 3-D steady simulations were performed under 13mm, 19mm and 25mm guide vane openings. Three groups of operating points under the three GVOs were chosen based on experimental validation to investigate the influence of guide vane setting on flow patterns upstream and downstream. The results reveal that, the guide vane setting will obviously change the flow pattern downstream, which in turn influences the flow upstream. It shows a strong effect on hydraulic loss (power dissipation) in the guide and stay vanes. It is also found that the hydraulic loss mainly comes from the flow separation and vortices. In addition, in some operating conditions, the change of guide vane opening will change the flow angle at the runner inlet and outlet, which will change the Euler momentum (power input). The joint action of Euler momentum and hydraulic loss results in the change of the head characteristics.

• Physical Therapy Korea
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• v.6 no.3
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• pp.11-21
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• 1999

Human balance is maintained through a complex process involving sensory detection of body motions, integration of sensorimotor information within the central nervous system, and execution of appropriate musculoskeletal responses. The basic task of balance is to position the body center of gravity (COG) over some portion of the support base. When the COG extends beyond the base of support, the person has exceeded the limits of stability (LOS). At this point, a step or stumble is required to prevent a fall. Automatic postural responses operate to keep the COG over the base of support. They are a set of functionally organized, long-loop responses that act to keep the body in a state of equilibrium. There are four commonly identified automatic postural responses, or strategies. These are ankle strategy, hip strategy, suspensory (knee) strategy, and stepping strategy. Thus, the purpose of this study was to evaluate the LOS using various knee strategies. Forty subjects participated in this study. The subjects were comprised of 20 males and 20 females who were without neurologic, orthopaedic or balance performance impairments. The LOS was measured with a Balance Performance Monitor (BPM) Dataprint Software Version 5.3. The results of this study were as follows: 1) Knee joint angle which is to increase stability of standing balance with using knee strategy was at mid-range. 2) There were statistically significant differences in anteroposterior LOSs according to the knee strategy. 3) There were no statistically significant differences in mediolateral LOSs according to the knee strategy. 4) There were statistically significant differences of anteroposterior LOSs with using knee strategy according to gender. 5) There were no statistically significant differences in mediolateral LOSs with using knee strategy according to gender.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.1
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• pp.42-47
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• 2014

Decrease of occlusal vertical dimension (OVD) due to loss of teeth structure and destruction of the occlusal plane by severely worn dentition may cause cross bite or temporomandibular joint disorder by following change of facial feature or the loss of anterior guidance. Full mouth rehabilitation via an increase of the OVD can be considered to avoid this problem and proper evaluation of patient's OVD is essential. An 80 year old male visited for overall prosthodontic treatment, cross bite due to continuous wear and following decrease of the OVD were observed. We analyzed the existing occlusal relationship using the diagnostic cast, the radiographic evaluation and clinical test, and then proper increase of OVD was selected. The new OVD on diagnostic wax up was placed by the temporary restoration. After 3 months of observation period, final restoration with fixed partial dentures and implant overdenture were made. Throughout the follow-up period of 8 months, the aesthetic and functional improvement can be obtained.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.3
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• pp.119-132
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• 2023

The loss of posterior occlusal support due to tooth loss is likely to lead to compensatory protrusion and labial tilt of the anterior teeth, which may be accompanied by a deep bite and a decrease in vertical dimension. The patient may suffer from a decrease in masticatory efficiency, inaccurate pronunciation, facial appearance changes, and temporomandibular joint disorder, so stable occlusal formation with support of posterior occlusion and restoration of vertical dimension is necessary. We report the case of a patient with reduction of vertical dimension, and inaccurate pronunciation due to multiple tooth loss who underwent full mouth rehabilitation with increased vertical dimension accompanied by phonetic analysis and achieved satisfactory functional and aesthetic results.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.2
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• pp.128-134
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• 2012

Purpose: The purpose of this study was to compare the screw joint stability between the CADCAM custom-made implant abutment and the prefabricated implant abutment by measuring the reverse torque value after cyclic loading. Materials and methods: Twelve screw type implants (Implantium, Dentium Co., Seoul, Korea) were embedded in aluminum cylinder with acrylic resin. The implant specimens were equally divided into 3 groups, and connected to the prefabricated titanium abutments (Implantium, Dentium Co., Seoul, Korea), CADCAM custom-made titanium abutments (Myplant, Raphabio Co., Seoul, Korea) and CADCAM custom-made zirconia abutments (Zirconia Myplant, Raphabio Co., Seoul, Korea). The CAD-CAM milled titanium crown (Raphabio Co., Seoul, Korea) was cemented on each implant abutment by resin cement. Before cyclic loading, each abutment screw was tightened to 30 Ncm and the reverse torque value was measured about 30 minutes later. After the crown specimen was subjected to the sinusoidal cyclic loading (30 to 120 N, 500,000 cycles, 2 Hz), postloading reverse torque value was measured and the reverse torque loss ratio was calculated. Kruskal-Wallis test was used for statistical analysis of the reverse torque loss ratio. Results: The CADCAM custom-made titanium abutments presented higher values in reverse torque loss ratio without statistically significant differences than the prefabricated titanium abutments ($P$>.05). Reverse torque loss ratio of the custom-made zirconia abutments was significantly higher compared to that of the prefabricated titanium abutments ($P$=.014). Conclusion: Within the limitation of the present $in-vitro$ study, it was concluded that there was no significant difference in screw joint stability between the CADCAM custom-made titanium abutments and the prefabricated titanium abutments. On the other hand, the CADCAM custom-made zirconia abutments showed lower screw joint stability than prefabricated titanium abutments.

• The Journal of Fisheries Business Administration
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• v.15 no.1
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• pp.81-95
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• 1984

The international marine system was plunged into the age of divided occupation with the adoption of the United Nations Convention on Law of the Sea in April, 1982. The exclusive economic zone of 200 Nautical miles set up by the Convention confirms the assertions of many coastal states whose fishing industries are not well-developed. However, it is unfavorable to the countries whose fisheries are being carried on in deep-sea, because the coastal state has sovereign rights to conserve and manage living resources in it. Under the circumstances the Korean deep-sea fisheries had to find ways out of the difficulties. The ways may be divided into two ways, namely, licensed fishing and joint-venture fishing. The former type becomes unfavorable to foveign fisheries because of decreasing quarts, rising fees and remunerations. The latter type properly meets the wishes of countries concerned and has some merits. However, there is a possibility of bearing the risk in case of investment in developing countries. The insurance system is effective to make up for the loss from the risk, although not perfect. The deep-sea fisheries depressed now by accumulated difficulties need more financial support from the Goverment for the active promotion of overseas joint-venture.

• The Korean Journal of Applied Statistics
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• v.29 no.7
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• pp.1411-1419
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• 2016

Nonparametric procedures in randomized block design was proposed by Friedman (1937) as a general alternative. This method is used to find out the difference in treatment effect. It can cause a loss of inter block information using the ranking in each block. This paper proposed nonparametric procedures using an aligned method proposed by Hodges and Lehmann (1962) to reduce block information based on joint placement suggest by Jo and Kim (2013) in a randomized block design. We also compared the power of the test of the proposed procedures and established method through a Monte Carlo simulation.

• Clinics in Shoulder and Elbow
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• v.1 no.1
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• pp.46-50
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• 1998

The superior shoulder suspensory complex is composed of glenoid fossa, coracoid process, coracoclavicular ligament, distal clavicle, acromioclavicular ligament, acromion. Traumatic double disruptions of this complex lose its suspensory action on the shoulder joint and result in functional loss and deformity. Careful radiologic evaluation and appropriate management are required for injuries to this complex. Ipsilateral fractures of clavicle and scapula create unstable anatomic situation on shoulder joint. Conservative treatment usually fails to achieve good functional recovery due to rotator cuff weakness, nonunion, delayed union, malunion and neurovascular injury. Authors studied the result of operative treatment of ipsilateral clavicle and scapular fractures to prevent such complications. Seven cases were treated with open reduction and internal fixations of clavicle alone or clavicle and scapula simultaneously and followed up for nineteen months(twelve months - thirty-eight months). All but one patient showed good or excellent functional result according to the scoring system of Rowe. Poor result was developed in the case which had brain injury. Rigid fixations of clavicle alone or clavicle and scapular fractures both can achieve stable reduction of the fractures and prevent sequelae. We concluded that operative treatment of ipsilateral fractures of clavicle and scapula is safe and yields predictable good results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.4
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• pp.47-54
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• 2013

The main cause of die failure in hot forging is wear. Die wear directly generates the gradual loss of part tolerances, thereby causing deterioration in the dimensional accuracy of a forged part. It is very important to estimate forging cycles, called as die life, at which the die should be repaired or replaced. In this study, in order to estimate the hot forging die life, the finite element simulation of wear on an asymmetric part like a ball joint socket used in vehicle was carried out based on Archard's model. Finite element simulation results were compared with wear amounts of a used die that were measured using a contact stylus profilometer. The simulation results were in relatively good agreement with measurements obtained from the virtual die which was used by 7,000 forging cycles in a forging industry. Consequently, the die life in the hot forging of the ball joint socket was estimated by 10,500 forging cycles on the finisher die.

• Clinics in Shoulder and Elbow
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• v.9 no.2
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• pp.251-254
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• 2006

The anterior interosseous syndrome is an entrapment neuropathy which can be caused by several different etiologies. It is also clinically known that it weakens flexor pollicis longus, flexor digitorum profundus to the index and long fingers without loss of finger sensory. We have experienced anterior interosseous syndrome which found to be rare to ordinary conservative treatment, i.e. application of Kenny-Howard brace, given to a patient with acromioclavicular separation type III. We also review related articles.