• Journal of the Korean Geotechnical Society
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• v.21 no.1
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• pp.51-58
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• 2005

The use of geogrid for SRW systems and bridge abutment has increased rapidly over the past 10 years in Korea. The concept of segmental retaining walls and reinforced soil is very old and for example The Ziggurats of Babylonia(i.e. Tower of Babel) were built some 2,500 to 3,000 years ago using soil reinforcing methods very similar to those described in current design. Modern SRW(Semental Retaining Wall) units were introduced in 1960's as concrete crib retaining wall systems. In this paper, the friction properties between segmental concrete units and geogrid are investigated by performing various tests.

• Advances in pediatric surgery
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• v.1 no.2
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• pp.177-180
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• 1995

A 2-day-old male (Premie, Large for gestational age(LGA), Intrauterine period(IUP) 33 weeks, birth weight 2,955 gram) was transferred with marked abdominal distention, bilious return via the orogastric tube, respiratory difficulty, and generalized edema (hydrops fetalis). He was born by cesarean section to a 36 year-old mother. Antenatal ultrasonogram at IUP 31 weeks demonstrated multiple dilated bowel loops suggestive of intestinal obstruction. There was no family history of cystic fibrosis. Simple abdominal films disclosed diffuse haziness and suspicious fine calcifications in the right lower quadrant. Barium enema demonstrated a microcolon. Sweat chloride test was not available in our institution. At laparotomy, there noted 1) a segmental volvulus of the small bowel with gangrenous change, associated with meconium peritonitis, 2) an atresia of the ileum at the base of the volvulus, and 3) the terminal ileum distal to the volvulus was narrow and impacted with rabbit pellets-like thick meconium. These findings appeared to be very similar to those of a complicated meconium ileus. In summary, the ileal atresia and meconium peritonitis seemed to be caused by antenatal segmental volvulus of the small intestine in a patient with probable meconeum ileus.

• Korean Journal of Veterinary Research
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• v.13 no.2
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• pp.103-109
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• 1973

By employing the vinylite and neoprene latex corrosion technique, the ramification and arrangement of A. renalis were observed in fifty adult dogs (100 kidneys). Obtained results were as follows: 1. In the dog a single renal artery arosed on each side from abdominal aorta in 99% and double renal arteries in 1%, a single bifurcated into the ramus dorsalis and ramps ventralis from which 2-6 segmental arteries originated. 2. The dorsal ventral planes of the kidney were divided separately into 3-6 vascular segments by the segmental artery into the parenchyma. Of them four segments were mostly frequent (in 73% of right kidney and 72% of left). 3. The ramifying method of the segmental artery from the ramus dorsalis et ventralis was divided 3 types and 12 kinds. 4. In 30 of 100 kidneys, either dorsal or ventral plane of a kidney was supplied from interlobar or segmental arteries belonging to the opposite ramps. In 29 of them, the dorsal plane was supplied from the ventral ramus. 5. Six right and 11 left kidneys had a common segment in the Extremitas cranialis of the kidney.

• Journal of the Earthquake Engineering Society of Korea
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• v.13 no.2
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• pp.15-27
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• 2009

The purpose of this study is to investigate the seismic behavior of precast segmental PSC bridge columns. For the analysis of reinforced concrete structures, a computer program named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) is used. To represent the interaction between tendon and concrete of a prestressed concrete member, a bonded or unbonded tendon element based on the finite element method is used. A joint element is modified to predict the inelastic behaviors of segmental joints. The solution of the equations of motion is obtained by numerical integration using Hilber-Hughes-Taylor (HHT) algorithm. The proposed numerical method gives a realistic prediction of seismic behavior throughout the input ground motions for numerical examples.

• Journal of Electrical Engineering and Technology
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• v.12 no.5
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• pp.1864-1871
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• 2017

This paper presents a design of a 2-phase segmental stator type 4/3 switched reluctance motor (SRM) for air-blower application. The air-blower requires only one direction rotation, high rotor speed without torque dead-zone. In order to satisfy the requirements of the load, the rotor of the 4/3 proposed SRM is designed with wider rotor pole arc and non-uniform air-gap is applied on the rotor shape. With a special rotor structure, the motor generates a wider positive torque region and has no torque dead-zone. The stator of the proposed SRM is constructed with two segmental C-cores, and there are no magnetic connections between 2 C-cores. The flux follows in a short closed loop in each C-core and has no reversal flux in the stator. The static and dynamic characteristics of the proposed motor are analyzed by the finite element method (FEA) and Matlab-Simulink, respectively. In order to verify the design, a prototype of the proposed motor has manufactured for laboratory test. The performance of the proposed motor is verified by the simulation and experimental results.

• Journal of Korean Neurosurgical Society
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• v.55 no.1
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• pp.36-39
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• 2014

Treatment of complex aneurysms usually entails not only direct clipping but also alternative treatment modality. We recently experienced a case of vertebral artery dissecting aneurysm and obtained good treatment outcomes. Our case suggests that the endovascular segmental occlusion with posterior inferior cerebellar artery (PICA) to PICA side anastomosis might be a good treatment option in patients with complex vertebral artery dissecting aneurysms. A 45-year-old woman has a left vertebral dissecting aneurysm with dizziness. Based on the aneurysmal morphology and the involvement of PICA, the patient underwent side to side anastomosis of the PICA. This was followed by the endovascular segmental coil occlusion. The aneurysmal sac was completely obliterated. At a 2-year follow-up, the patient achieved a good patency of both PICA. In conclusion our case suggests that the endovascular segmental occlusion of the parent artery followed by PICA to PICA bypass surgery through a midline suboccipital approach is a reasonable multimodal treatment option in patients with complex vertebral artery dissecting aneurysms.

• Journal of Korean Neurosurgical Society
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• v.40 no.5
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• pp.346-350
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• 2006

Objective : The ability to induce segmental lordosis has been reported to be marginal with transforaminal lumbar interbody fusion[TLIF]. Therefore, we analyzed the short-term radiological outcomes of TLIF using $8^{\circ}$ wedged cages for isthmic spondylolisthesis. Methods : Twenty-seven patients with isthmic spondylolisthesis who underwent single level TLIF with pedicle screw fixation[PSF] using $8^{\circ}$ wedged cages were retrospectively evaluated. Changes in disc height, degree of anterolisthesis, segmental lumbar lordosis, whole lumbar lordosis and L1 axis S1 distance were evaluated using standing lateral radiographs before surgery, at 6 weeks follow-up and at the final follow-up. Results : The mean age of the patients was 49.9 years [range, 38 to 64 years]. The affected levels were L4-5 in 17 cases and L5-S1 in 10. There were 18 cases of Grade I isthmic spondylolisthesis and 9 cases of Grade II. At a mean follow-up duration of 9.9 months [range, 6 to 18 months], the disc height [p< 0.001] was significantly increased, and the degree of anterolisthesis was significantly reduced [p< 0.001]. Regarding the sagittal balance, the segmental lumbar lordosis was significantly increased [p=0.01], but other parameters were not significantly changed after surgery. Conclusion : TLIF with PSF using $8^{\circ}$ wedged cages significantly increased the segmental lumbar lordosis.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.85-88
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• 2008

The purpose of this study was to investigate the seismic behavior of precast concrete segmental bridge piers with shear resistance connecting structure. A model of precast concrete segmental bridge columns with shear resistance connecting structure was tested under a constant axial load and a cyclically reversed horizontal load. A computer program, RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), for the analysis of reinforced concrete structures was used. The proposed numerical method for the seismic behavior of precast concrete segmental bridge piers with shear resistance connecting structure is verified by comparison with reliable experimental results.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.2
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• pp.49-58
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• 1990

A numerical procedure is developed to analyze the time-dependent deflections of prestressed concrete bridges constructed by the segmental cantilever method. The developed computer program accounts for the time-dependent properties of prestressed concrete materials due to the varying modulus of elasticity, creep and shrinkage of concrete and the stress relaxation of prestressing steel. It also accounts for the stiffness increase due to the presence of the steel reinforcements and the effects of the shear deformation of the prestressed concrete bridge girders. The program is applied to a multi-span continuous segmental prestressed concrete bridge to demonstrate its capabilities and to explore the behavior characteristics of the segmental bridges.

• Korean Journal of Cleft Lip And Palate
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• v.14 no.1_2
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• pp.19-28
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• 2011

Maxillary anterior segmental distraction osteogenesis (DO) has been the alternative treatment option for patients with midfacial retrusion. The patient showed unilateral cleft lip and palate, and premaxillary distraction with rigid external device (RED) was planned to solve midface deficiency and to create alveolar space. Significant advancement of A point was observed, but relapse of A point was detected during consolidation period. The vertical position of the ANS was found to have moved downward. Axis of upper incisor decreased after DO. Maxillary anterior segmental DO is effective for treatment of patient with cleft lip and palate. The alveolar space is regained successfully, and the facial profile is improved without velopharyngeal problems.