• The Journal of Korean Physical Therapy
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• v.15 no.3
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• pp.295-345
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• 2003

This study investigated activation of cerebral cortex in patients with hemiplegia that was caused by neural damage. Key-point control movement therapy of Bobath was performed for 9 weeks in 3 subjects with hemiplegia and fMRI was used to compare and analyze activated degree of cerebral cortex in these subjects. fMRI was conducted using the blood oxygen level-dependent(BOLD) technique at 3.0T MR scanner with a standard head coil. The motor activation task consisted of finger flexion-extension exercise in six cycles(one half-cycles = 8 scans = $3\;sec{\times}\;8\;=\;24\;sec$). Subjects performed this task according to visual stimulus that sign of right hand or left hand twinkled(500ms on, 500ms off). After mapping activation of cerebral motor cortex on hand motor function, below results were obtained. 1. Activation decreased in primary motor area, whereas it increased in supplementary motor area and visual association area(p<.001). 2. Activation was observed in bilateral medial frontal gyrus, middle frontal gyrus of left cerebrum, inferior frontal gyrus, inter-hemispheric, fusiform gyrus of right cerebrum, superior parietal lobule of parietal lobe and precuneus in subjedt 1, parahippocampal gyrus of limbic lobe and cingulate gyrus in subject 2, and inferior frontal gyrus of right frontal lobe, middle frontal gyrus, and inferior parietal lobule of left cerebrum in subject 3 (p<.001). 3. Activation cluster extended in declive of right cellebellum posterior lobe in subject 1, culmen of anterior lobe and declive of posterior lobe in subject 2, and dentate gyrus of anterior lobe, culmen and tuber of posterior lobe in subject 3 (p<.001). In conclusion, these data showed that Key-point control movement therapy of Bobath after stroke affect cerebral cortex activation by increasing efficiency of cortical networks. Therefore mapping of brain neural network activation is useful for plasticity and reorganization of cerebral cortex and cortico-spinal tract of motor recovery mechanisms after stroke.

• Tribology and Lubricants
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• v.35 no.6
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• pp.323-329
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• 2019

Sapphire is currently used as a substrate material for blue light-emitting diodes (LEDs). The market for sapphire substrates has expanded rapidly as the use of LEDs has extended into various industries. However, sapphire is classified as one of the most difficult materials to machine due to its hardness and brittleness. Recently, a lap-grinding process has been developed to combine the lapping and diamond mechanical polishing (DMP) steps in a single process. This paper studies, the effect of wafer surface roughness on the chemical mechanical polishing (CMP) process by pressure and abrasive concentration in the lap-grinding process of a sapphire wafer. In this experiment, the surface roughness of a sapphire wafer is measured after lap-grinding by varying the pressure and abrasive concentration of the slurry. CMP is carried out under pressure conditions of 4.27 psi, a plate rotation speed of 103 rpm, head rotation speed of 97 rpm, and slurry flow rate of 170 ml/min. The abrasive concentration of the CMP slurry was 20wt, implying that the higher the surface roughness after lapgrinding, the higher the material removal rate (MRR) in the CMP. This is likely due to the real contact area and actual contact pressure between the rough wafer and polishing pad during the CMP. In addition, wafers with low surface roughness after lap-grinding show lower surface roughness values in CMP processes than wafers with high surface roughness values; therefore, further research is needed to obtain sufficient surface roughness before performing CMP processes.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.1 no.1
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• pp.27-30
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• 2008

Snapping triceps syndrome is a rare condition in which a distal portion of triceps and ulnar nerve dislocate over the medial epicondyle as the elbow is flexed or extended from flexed position. Because it is frequently misdiagnosed as other elbow pathologies, accurate diagnosis is essential and imaging study is often needed to confirm the abnormal movement of ulnar nerve and triceps. Ultraonography is a convenient and effective method which is able to allow continual visualization of soft tissue movement compared to the other imaging modality including MRI. We reported one patient of snapping triceps syndrome who was diagnosed with the use of dynamic ultrasonography and treated with ulna nerve anterior transposition and repositioning of medial head of triceps. And we also provide the usefulness of musculoskeletal ultrasonography for the diagnosis of snapping triceps syndrome.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1348-1357
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• 2011

The objective of this study was to compare the effect of Butylated Hydroxy Toluene (BHT), Pentoxifylline (PTX) and ${\alpha}$-tocopherol (Vit E) on semen quality parameters of Karan Fries bulls. The fortification of extender by various semen additives improves motility as well as fertility of spermatozoa. Split samples of 24 ejaculates of four Karan Fries bulls were extended in extender with or without various additives such as BHT, PTX and Vit E, and performance was evaluated at an interval of 0, 24, 48 and 72 h at refrigerated temperature (4-$7^{\circ}C$). Results of the present study revealed that addition of BHT, PTX and Vit E in extender improved sperm cell function, such as motility, viability, HOST, and acrosome integrity, as compared to the control during liquid storage up to 48 h of preservation at refrigerated temperature. There was no significant (p<0.05) difference between any of the additives up to 48 h of preservation. Overall, the results showed a significant (p<0.05) deterioration in motility after each storage interval. The results showed a significant deterioration in the acrosome integrity and plasma membrane integrity up to 48 h; subsequently, there was not much degradation of both the semen quality parameters. There was a significant increase in spermatozoal tail and total abnormality after each storage interval at refrigerator temperature (4 to $7^{\circ}C$); however, the head and mid-piece abnormalities were almost unaffected. Tail and total abnormality were least in extender fortified with BHT, PTX and Vit E at different hours of incubation as compared to the control. The addition of 1.5 mM BHT, 3.6 mM PTX and 1 mg/ml Vit E in the semen extender has more beneficial effect in terms of semen quality and preservability of spermatozoa.

• Journal of Korea Multimedia Society
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• v.14 no.10
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• pp.1287-1302
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• 2011

Clustering protocol that is used in wireless sensor network is an efficient method that extends the lifetime of the network. However, when this method is applied to an environment in which collected data of the sensor node easily overlap, sensor nodes unnecessarily consumes energy. In the case of clustering technique that uses a threshold, the lifetime of the network is extended but the degree of accuracy of collected data is low. Therefore it is hard to trust the data and improvement is needed. In addition, it is hard for the clustering protocol that uses multi-hop transmission to normally collect data because the selection of a cluster head node occurs at random and therefore the link of nodes is often disconnected. Accordingly this paper suggested a cluster-formation algorithm that reduces unnecessary energy consumption and that works with an alleviated link disconnection. According to the result of performance analysis, the suggested method lets the nodes consume less energy than the existing clustering method and the transmission efficiency is increased and the entire lifetime is prolonged by about 30%.

• Journal of Dental Rehabilitation and Applied Science
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• v.22 no.2
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• pp.111-123
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• 2006

A Study on the Fracture Strength of All-Ceramic Crown according to the Zirconia Coping Design using CAD/CAM System L. Bulgan, In-Ho Cho, Soo-Yeon Shin Department of Prosthodontics, Graduate School, Dankook University The fracture strength of prosthesis is important, because it affects the function, and long term success of prosthesis and teeth. The purpose of this study was to compare the fracture strength of zirconia coping designs. Experimental test group were classified into three designs according to coping design, Modified design: Zirconia coping margin was located at 1mm above the axiogingival line angle. Collarless design: The coping margin terminated at the axiogingival line angle Butt design: The coping margin was extended to the finishing line of prepared margin. A $Cercon^{(R)}$(Degussa, Germany) CAD/CAM system was used to make the zirconia coping. Fracture strength was measured using loading machine at a cross head speed of 1mm/min. The results were statistically analyzed using the one-way ANOVA and multiple comparison test. Statistical significance was set in advance at the probability level of less than 0.05. The result : I. Collarless($738N{\pm}155N$) and Modified($755N{\pm}185N$) groups showed significantly a lower fracture strength than Butt($1057N{\pm}262N$) group(p<0.05). II. There were no statistical differences of the fracture strength between Modified($755N{\pm}185N$) and Collarless($738N{\pm}155N$) groups. III. When comparing the fractured surface, all the group showed porcelain fracture, which were fractured at the labial surface of baked porcelain The butt design of the zirconia coping has higher fracture strength than modified and collarless design.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.3
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• pp.282-288
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• 2010

Surgery with the computer navigation system can make it possible to identify important anatomical structures which are difficult to be confirmed with the naked eye in the operation, and has extended their applications in various surgical fields. The head and neck surgery especially requires detailed anatomical knowledges and these knowledges have influences on postoperative functions and esthetics of a patient. In the orthognathic surgery, we should take osteotomies in the precise locations of the jawbones and move segments to the intended positions. There are so many important anatomical structures around the osteotomy-sites in the orthognathic surgery that the prevention of damage to these structures to obtain satisfactory results without any complication. There are vessels of the pterygoid plexus posterior to the pterygoid plate in the maxilla and the mandibular nerve enters the mandibluar foramen in the mandibular ramus. These locations should be confirmed perioperatively to avoid any injury to these structures. The navigation-assisted surgery may be helpful for this purpose. We performed navigational orthognathic surgeries with preoperative CT images and obtained satisfactory results. The osteotomy was performed in the proper location and damaging the surrounding important anatomical structures was avoided by keeping the saw away from them with the real-time navigation. It may be required to develop proper devices and protocols for the navigation-assisted orthognathic surgery.

• Journal of IKEEE
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• v.11 no.4
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• pp.165-170
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• 2007

The main goal of research concerning clustering protocols is to minimize the energy consumption of each node and maximize the network lifetime of wireless sensor networks. However, most existing clustering protocols mainly focused on the design and formation of clusters, leaving the consideration of communication between the cluster head and the sink behind. In this paper, we propose efficient multi path routing algorithm by using MAC-NET Cross-layering. multi path needed only one tiny packet from sink to setup. In addition proposed algorithm can be used for any cluster-based hierarchical inter-clustering routing algorithm. The simulation results demonstrate that proposed algorithm extended the overall survival time of the network by reducing the load of cluster heads. The performance of proposed algorithm is less affected by the extension of sensing field than other inter-clustering operation.

• Economic and Environmental Geology
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• v.23 no.4
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• pp.393-409
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• 1990

Synthetic seismograms and deduced characteristic properties of the non-geometrical $S^*$ and $P^*$ waves are presented. These waves are excited on the free surface or an interface between two different media by an inhomogeneous P wave from a point source nearby, and propagate as homogeneous waves in the media. Synthetic seismograms are computed using an extended reflectivity method designed for buried source and receiver. An efficient computational procedure for propagator matrices of layers is devised to reduce the computational time and the RAM memory size in the implementation of the reflectivity method. Radiation patterns are obtained from the particle motions of the four types of the "*" waves, i.e., the $S^*$ wave generated near the free surface, and the reflected $S^*$, transmitted $S^*$ and transmitted $P^*$ waves generated near an interface. Some patterns show polarity changes of displacements and others reveal monotonic or non-monotonic variation of amplitude depending on the velocity structure. The decaying trend of amplitude with increasing epicentral distance are also shown for the head wave type of the "*" waves.

• Korean Journal of Animal Reproduction
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• v.10 no.1
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• pp.19-26
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• 1986

This experiment was carried out to investigate the effect of bovine serum ablumin (BSA), sugars, glycerol equilibration time, straw size and thawing method on the survival index and the morphology of frozen boar spermatozoa. The results obtained were summarized as follow: 1. When the semen frozen in BF5 dilutor as pellet form was thawed in BTS at 37$^{\circ}$and 50$^{\circ}C$, BF5 dilutor with fructose showed higher sperm survival index than that with dextrose, however, when the semen was thawed on dry test tube at 37$^{\circ}C$, BF5 dilutor with sucrose showed higher sperm survival index than with other sugars. 2 When the semen forzen in BF5 dilutor with straw and thawed at 37$^{\circ}C$, BF5 dilutor with dextrose showed higher sperm survival index than those with other sugars, and there was no difference in sperm survival index between 0.5 and 1.0 ml straws. 3. The sperm survival index of frozen sperm was significantly (P<0.05) improved due to addition of BSA (0.05%) to BF5 dilutor. 4. When the extended semen with BF5 dilutor contatining 0.01 to 0.05% of BSA was frozen in the straw, the semen without glycerol equilibration showed significantly (P<0.05) higher sperm survival index than those with 2, 4 and 6 hrs glycerol equilibration time. 5. The sperm frozen in BF5 dilutor with dextrose or fructose, sucrose and raffinose showed 77 to 88% in normal acrosome rate and no difference among sugars. 6. The frozen semen showed lower normal acrosome rate than the first and second diluted semen, whereas the frozen semen showed higher swollen, damaged and missing acrosome rate than the first and second diluted semen. 7. Damaged and missing acrosome rate of sperm head due to freezing was somewhat inhibited by addition of BSA (0.01 to 0.05) to the BF5 dilutor.