• Proceedings of the KIEE Conference
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• 2000.07b
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• pp.754-756
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• 2000

In this paper, the I-PD control algorithm using the coefficient diagram method(CDM) controller design of the Linear DC Motor(LDM) is presented. Recently LDM has been used to obtain the fine results of the dynamic characteristic for straightly moving condition. The I-PD control algorithm has a robust response to force disturbance. The effectiveness of I-PD is shown by simulations and comparison with PID.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.3
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• pp.316-321
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• 2004

In this paper, we have developed a new mounting head system for flip chip. The proposed head system consists of a macro/micro positioning actuator for stable force control. The macro actuator provides the system with a gross motion while the micro device yields fine tuned motion to reduce the harmful impact force that occurs between very small sized electronic parts and the surface of a PCB(printed circuit board). In order to show the effectiveness of the proposed macro/micro chip mounting system, we compared the proposed system with the conventional chip mounting head equipped with a macro actuator only. A series of experiments were executed under the mounting conditions such as various access velocities and PCB stiffness. As a result of this study, a satisfactory voice coil actuator as the micro actuator has been developed, and its performance meet well the specifications desired for the design of the chip mounting head system and show good correspondence between theoretical analysis and experimental results.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1997.04a
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• pp.5-5
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• 1997

Rapidly-solidified P/M aluminium alloys for automobile and home appliance industries were developed. Rapidly-solidification made it possible to refine microstructures and to expand the range of alloy composition. For example, Al-Si alloys containing transition metal have lower thermal expansion coefficient, more excellent wear resistance, higher strength, and better machinability than those of conventional aluminium alloys. Therefore, in Japan, the technologies on powder-extrusion and powder-forging of aluminium alloy powders are developed for fifteen years, and applied to several parts, such as cylinder liners of motor cycle engines, rotors and vanes of compressors for car air conditioner, oil pump rotor for racing car, and so on. In this presentation, applications for automobile are mentioned. In particular, cylinder liners made of particle-dispersed composites with fine alumina and graphite are in detail described.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.264-267
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• 2005

Soft magnetic iron powders have been coated with polyester or phenol resin. And the coated powder (soft magnetic composite) have been pressed into ring type core over the pressure of 870 MPa. Green density, magnetic flux density, permeability, core loss of the samples were measured to look at the effect of the coating materials and the amount of them. Green density is increased with the amount of coating materials and shows the maximum value, 6.5 $g/cm^3$ at 5 w/o, but decreased over it. And lowest value of the core loss is showed for the 5 w/o coated samples.

• CELLMED
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• v.13 no.6
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• pp.6.1-6.3
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• 2023

Objective: Malunion of distal radial fracture can result in pain, stiffness, and decreased function of the affected limb. Occupational therapy intervention can improve outcomes in these patients, but there is limited research on the effectiveness of such interventions. Case Description: This case report describes the occupational therapy intervention and outcomes for a 44-year-old female patient with malunion of left distal radial fracture. The patient received 8 weeks of occupational therapy intervention consisting of therapeutic exercises, joint mobilization, and fine motor activities. The patient demonstrated significant improvements in range of motion, grip strength, and activities of daily living (ADL) in her left hand. The patient also reported less pain and greater ease in performing activities of daily living. Conclusion: Occupational therapy intervention can be effective in improving outcomes for patients with malunion of distal radial fracture. This case report highlights the importance of early intervention and interdisciplinary collaboration among healthcare professionals to optimize patient outcomes. Further research is needed to explore the effectiveness of occupational therapy interventions for patients with malunion of distal radial fracture.

• Applied Microscopy
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• v.26 no.1
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• pp.17-31
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• 1996

The venomous apparatus of the black widow spider, Latrodectus mactans, is composed of chelicera and paired venom glands in the cephalothorax. Each glands is surrounded by a thin adventitia and striated muscular bundles resting on a basal membrane. Along the musculature neuromuscular synaptic contacts are formed by a motor axon and the muscle fibers. The secretory epithelium, which made up of simple and long columnar cells with extensive finger-like processes, creates a simple acinar gland. The secretory surfac is increased by a sort of fringes extended from the basal membrane into the gland lumen, and the luminal surface of the epithelium is marked by the presence of closely spaced microvilli. The venoms of the black widow spider are produced from two types of secretory granules within the epithelial cells. During the secretory phase, these granules are transformed into droplets and suffering a condensation. Finally the secretory products are released by the apocrine secretion. After the gland is emptied, the basal epithelial cells present a high proliferative process and regenerate the columnar epithlial cells.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.5 s.170
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• pp.103-112
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• 2005

This paper presents one-axis high precision scanning system and illustrates the design of modified $X-Y-{\theta}$ stage as a tracker using VCM and commercialized air bearings for it. The scanning system for 100nm resolution is composed of the 3-axis stage and one axis long stroke linear motor stage as a follower. In this study a previous proposed and presented structure of VCM for the fine stage is modified. The tracker has 3 DOF($X-Y-{\theta}$ motions by four VCM actuators which are located on the same plane. So 4 actuating forces are suggested and designed to create least pitch and roll motions. This article will show about the design especially about optimal design. The design focus of this fine stage is to have high acceleration to accomplish high throughput. The optimal design of maximizing acceleration is performed in restrained size. The most sensitive constraint of this optimal design is heat dissipation of coil. There are 5 design variables. Because the relationship between design variables and system parameters are quite complicated, it is very difficult to set design variables manually. Due to it, computer based optimal design procedure using MATLAB is used. Then, this paper also describes the procedures of selecting design variables for the optimal design and a mathematical formulation of the optimization problem. Based on the solution of the optimization problem, the final design of the stage is also presented. The results can be verified by MAXWELL. The designed stage has the acceleration of about 5 $m/s^{2}$ with 40kg total mass including wafer chuck and interferometer mirror. And the temperature of coil is increased $50^{\circ}C$. In addition, the tracker is controlled by high precision controller system with HP interferometer for it and linear scaler for the follower. At that time, the scanning system has high precision resolution about 5nm and scanning resolution about 40nm in 25mm/s constant speed

• The Journal of Korean Physical Therapy
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• v.29 no.4
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• pp.211-217
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• 2017

Purpose: The purpose of this study was to trace the development of premature babies who had undergone neurodevelopmental treatment in the neonatal intensive care unit and to identify the effects of early neurodevelopmental treatment on the development of premature babies. Methods: Fifty-one premature babies, who had been hospitalized in the neonatal intensive care unit and received an infant motor performance test and Bayley scales-III evaluation of their developments during the six months of corrected age were included. They were divided into three groups: the intervention group (n=16), control group (n=23), and comparison group (n=12), depending on the risk of developmental delays and the existence of an intervention. The results of this study were analyzed using SPSS 22.0 for windows. The statistical significance level was set at ${\alpha}=0.05$. Results: Regarding the infant motor performance test scores for each group before the intervention, at two weeks after the start of intervention, and at post-conception of 40 weeks, the intervention group showed a significantly higher improvement than the control or comparison group (p<0.01). With respect to the Bayley scales-III at the corrected age of six months, the intervention group exhibited statistically significant differences from the control group in the domains of language and fine movements (p<0.01). Conclusion: The findings of this study could confirm that the early neurodevelopmental treatment of premature babies in the neonatal intensive care unit has continuous effects on the development of premature babies even after being discharged from the hospital.

• Child Health Nursing Research
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• v.15 no.1
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• pp.34-41
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• 2009

Purpose: In this study, a Checklist for Infant and Child Developmental Screening (CICDS) was designed for use by primary pediatric health care providers to identify infants and children with developmental delays. Method: Each Item of the CICDS was constructed referring to existing tools. In 5 public health centers of B city, 500 infants and children were selected at the age of 2, 4, 6, 12, & 18 months and assessed between October and December 2006, CICDS and the Korea Denver II were compared to assesses the validity of the CICDS. Results: The CICDS consisted of 30 items in 4 areas; Personal-social, Fine motor-adaptive, Language, Gross motor. The results of the CICDS correlated significantly with the result of Korea Denver II at each month of age. (r=0.19; p<.01). Of the 500 infants and children, 148 were "suspect" for development delays (sensitivity of 96%, specificity 73%). On the CICDS, 74.6% of children received same result as Denver II. In discriminant analysis, 89.9% of children were identified correctly by CICDS (p<.01). Conclusion: CICDS could be a screening procedures to quickly and reliably identify infants with developmental delays. It also provides a mean of recording measurements of development characteristics.

• Clinical and Experimental Pediatrics
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• v.52 no.9
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• pp.1044-1047
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• 2009

A 13-year-old girl with psoriasis of the elbow, trunk, and face suddenly developed a severe headache followed by left hemiparesis and facial palsy. Brain magnetic resonance imaging showed an acute infarction of the right temporofrontal lobe and basal ganglia on the T2- and diffusion-weighted images. Cerebral angiography showed pre-occlusive irregular scalloped stenosis (99%) in the proximal M1 segment of the right middle cerebral artery and a web-like stenosis at the supraclinoid portion of the right internal carotid artery (ICA) suggestive of a spontaneous intracranial ICA dissection. The patient was administered a low dose of dipyridamole, and a rehabilitation program was initiated. Headache, left motor weakness, and facial droop improved within a week. However, mild left facial palsy and reduced fine motor function of the left hand were still present after 3 weeks. We report a rare case of spontaneous intracranial ICA dissection in a child with psoriasis.