• ALGAE
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• v.21 no.1
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• pp.109-124
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• 2006

Responses to various types of mechanically induced wounding were followed in the giant-celled Caulerpalean species, Derbesia tenuissima, using time-lapse video-microscopy. Gametophyte vesicle cells. Puncture wounding: the gametophyte cell seals the puncture in 5 min. This is followed by cycles of ruptures and sealing, ending with full recovery in 24 hrs. Cut wounding: the protoplast immediately retracts away from the wall and reforms an intact, deflated protoplast that expands to fill the original cell within 21 hrs. Crush wounding (internal). When retained within the cell wall many protoplast fragments condense, round up, and coalesce; the reconstituted protoplast expands until it attains complete recovery, filling the original cell shape in 12 hrs. Crush wounding (external). Protoplast fragments extruded from the crushed cell are more numerous and smaller taking longer to recover. Most fragments become spherical, transforming into small viable cells capable of reproduction in several days. Sporophyte filaments. Crush wounding creates many small fragments that initially condense, coalesce and then expand within the wall to restore a complete filament with normal cytoplasmic streaming within 5 hrs. Reproduction: gametophyte. Our culture isolates produce more females than males (30:1). Gametangia develop one day before discharge that occurs explosively (1/6 sec) at first morning light. The vesicle cell forms successive gametangia every 14 days. Sporophyte. Each sporangium develops on a lateral branch that becomes isolated by the creation of successive basal plugs. After cytoplasmic cleavage and differentiation the stephanokont spores are discharged. The spores settle quickly and germinate forming gametophyte cells.

• International Journal of Fluid Machinery and Systems
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• v.2 no.4
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• pp.295-302
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• 2009

The flow in the draft tube cone of Francis turbines operated at partial discharge is a complex hydrodynamic phenomenon where an incoming steady axisymmetric swirling flow evolves into a three-dimensional unsteady flow field with precessing helical vortex (also called vortex rope) and associated pressure fluctuations. The paper addresses the following fundamental question: is it possible to compute the circumferentially averaged flow field induced by the precessing vortex rope by using an axisymmetric turbulent swirling flow model? In other words, instead of averaging the measured or computed 3D velocity and pressure fields we would like to solve directly the circumferentially averaged governing equations. As a result, one could use a 2D axi-symmetric model instead of the full 3D flow simulation, with huge savings in both computing time and resources. In order to answer this question we first compute the axisymmetric turbulent swirling flow using available solvers by introducing a stagnant region model (SRM), essentially enforcing a unidirectional circumferentially averaged meridian flow as suggested by the experimental data. Numerical results obtained with both models are compared against measured axial and circumferential velocity profiles, as well as for the vortex rope location. Although the circumferentially averaged flow field cannot capture the unsteadiness of the 3D flow, it can be reliably used for further stability analysis, as well as for assessing and optimizing various techniques to stabilize the swirling flow. In particular, the methodology presented and validated in this paper is particularly useful in optimizing the blade design in order to reduce the stagnant region extent, thus mitigating the vortex rope and expending the operating range for Francis turbines.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.229-239
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• 2020

The purpose of this study was to help young people with mild intellectual disabilities with counseling and self-supporting life experiences. The topic of the counseling contents could be categorized as follows: "institutional life was clumsy and hard, but it was also full of memories," "my adolescent was aching, growing, and lonesome," "an irresistibie being," "independence process is filled with anxiety, excitement." In his process of going independent, the subject showed a strong will for the preparation for independence where he gets through the unfavorable situation surrounding the arduous and lonely independent process. This result proves the effectiveness of the therapeutic intervention based on the coping skills that meet the needs of the social situation for the adolescents who are discharged from institutions in their independence preparation and job search.

• Journal of Institute of Convergence Technology
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• v.2 no.1
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• pp.24-30
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• 2012

In this study, the trucks(2.9-liter) have been developed to use DME as fuel, and performance test of the vehicle's DME engine, power, emissions, fuel economy and vehicle aspects was conducted. For experiments, the fuel system(common-rail injectors and high-pressure pump included) and the engine control logic was developed, and ECU mapping was performed. As a result, the rail pressure from 40MPa to approximately 65% increase compared to the base injector has been confirmed that. Also, the pump discharge flow is 15.5 kg/h when the fuel rail pressure is 400rpm(40 MPa), and the pump discharge flow is 92.1 kg/h when the fuel rail pressure is 2,000rpm(40MPa). The maximum value of full-load torque capability is 25.5kgfm(based on 2,000rpm), and more than 90% compared to the level of the diesel engine were obtained. The DME vehicle was developed in this study, 120 km/h can drive to the stable, and calculated in accordance with the carbon-balance method of fuel consumptions is 5.7 km/L.

• Clean Technology
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• v.17 no.3
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• pp.259-265
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• 2011

The textile industry is suffered from air pollution problems which must be resolved. In particular, white smoke and odor after the tenter process require abatement. The major air pollution problem in the textile industry occurs during the finishing stages, where various chemicals are used for coating the fabrics. Lubricating oils, plasticizers, and water repellent chemicals are the fabric treatment chemicals. The coated fabrics are cured by heating in tenter facility. In this process, most of air pollutants emitted into the air. White smoke is basically made up of tiny solid or liquid particles of VOCs less than one micron in size. The oil mist can be carried over long distance from their point of origin. The most effective method of removing odor from tenter process is to get rid of tiny oil mist at the emitted gas. For this reason, the full-scale EFC (Electric Fume Collector) of 700 CMM was tested for removing odorous substances emitted from tenter facility. As a result of this study, odor and white smoke can be eliminated effectively and quite large amounts of oil can be recovered.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.166-171
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• 2008

This paper presents high efficiency control system of automotive 35W electronic ballast for high intensity discharge(HID) lamp using switching flyback converter with variable frequency. Considering performance, size and efficiency of ballast, the flyback converter is designed with planar transformer in converter stage. HID lamp demands a highly efficient ballast and very complex control circuitry that can control complex transient state for applying to automotive. The proposed electronic ballast system is composed of a flyback converter using planar transformer, a full bridge inverter, and a step up igniter. In this system, switching frequency of flyback converter is controlled by varying input voltage of HID ballast and the price and the size of HID ballast using planar transformer can be reduced. The performance and efficiency of the posed system are verified through various the experiment results.

• Journal of Chest Surgery
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• v.6 no.1
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• pp.89-94
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• 1973

Esophagel atresia and tracheoesophageal fistula may occur as separate entities but usually occur in combination. First described by Durston in 1670, esophageal atresia was not successfully treated until 1939 when Ladd in Boston and Leven in St. Paul obtained the first survivors utilizing the methods of gastrostomy, esophagostomy and extrapleural ligation of the tracheoesophageal fistula as multiple operations which required months of hospitalization. Two years later Cameron Haight performed the first successful primary repair and afterward about 2000 cases of esophageal atresia with distal tracheoesophageal fistula reported in the world. In Korea, there appeared about 27 cases in the literature and 8 successful repaired cases noted in these year. Anther report two cases of esophageal atresia, of which one case was successfully treated with Haight`s method. Case 1.: Normal full term delivered boy with chief complaints of respiratory difficulty and persistent drooling with chocking, 3. lkg, was admitted with emergency 5 hours after delivery. Physical findings revealed no specific abnormal signs except distended abdomen and grunting respiration. Esophagograrn and bronchogram revealed proximal esophageal atresia and distal tracheoesophageal fistula proximal to the carina. Parent refused operative therapy and patient died 24 hours after discharge. Case 2. :3. lkg. normal full term delivered girl was admitted 4 days after delivery with chief complaints of regurgitation after feeding, chocking, cyanotic spell and fever since the day after delivery. Physical examination revealed persistent drooling, grunting respiration, and fever with moderate dehydration. Tracheoesophageal suction and fluid therapy with antibiotics improved her condition and subsided ]pneumonic condition. Esophagogram revealed markedly dilated proximal esophagus as blind loop and stomach distended with gas, and repairing operation as Haight`s method was performed on the 7th day after delivery. Patient tolerated all the operative procedure well and recovered uneventfully. Esophagogram on the 7th postoperative day showed passage of the lipiodol through the anastomotic side with moderate stricture,and feeding permitted. Patient tolerated all the feeding amount well and discharged on the 11th postoperative day. Followup revealed intermittent regurgitation after feeding and corrected with bougination.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.3
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• pp.65-72
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• 2020

A refrigerator equipped with an ice dispenser has ice cubes in its ice bucket to discharge the required amount of ice. On the other hand, the ice cubes in the bucket may clump together if the refrigerator is filled with ice and is not used for a long time or during normal operation. Although a mechanism for separating the ice mass is provided, the ice mass cannot be removed completely if the ice blocking is severe. To solve this problem, after investigating the existing research on the process of ice entanglement and the separation force, this study tested ice extraction under a range of conditions of artificially entangled ices. In this process, new mechanisms are proposed to resolve the problem of existing ice storage features that prevent the extraction of ice and to expand the working radius of the icebreaking mechanism for full extraction. The prototype of the proposed mechanism was also fabricated in an actual refrigerator. As a result, the proposed shape and mechanism could extract the ice cubes in the bucket completely, while the existing ice dispenser could extract only 65%.

• Journal of Veterinary Clinics
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• v.28 no.2
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• pp.262-266
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• 2011

A 4-year-old intact male, Maltese dog weighing 2.2 kg was presented for evaluation of tachypnea and hyperthermia. On initial evaluation, the dog was dyspneic, but alert and responsive. Muffled heart sound was noted with auscultation of the right hemithorax. The radiographic findings were consolidation of the right middle lung lobe, pleural effusion, and abdominal fluid accumulation. Thoracic computed tomography confirmed a contrast-enhancing mass within the right middle lung lobe. Surgical exploration of the thoracic cavity was performed using a right fifth intercostal thoracotomy. Examination of the right lung lobe revealed $360^{\circ}C$ torsion of the right middle lung lobe at the level of the hilus, in a clockwise direction. Lung lobectomy was performed using a thoracoabdominal stapling device with 2.5-mm vascular staples. Full-thickness intestinal biopsy by exploratory laparotomy was taken from the jejunum for histological assessment. Histopathologic examination of the full-thickness intestinal biopsy revealed distended lacteal located within the submucosa of the jejunum. Intestinal lymphangiectasia was resolved with prednisone and low fat diets. Subsequent communication with the owner revealed that the patient was in good health 6 months post-discharge.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.45 no.5
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• pp.241-253
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• 2019

This study evaluated and compared the donor site morbidity following minimally invasive and conventional open harvesting of iliac bone for secondary alveolar bone grafting in cleft palate patients. A thorough electronic search of PubMed, Google Scholar, EMBASE, and an institutional library and manual search of various journals was done; Inclusion criteria: 1) full-text articles using a minimally invasive or conventional open harvesting technique for iliac bone for secondary alveolar grafting in cleft palate patients and 2) articles published between January 1, 2001 and June 30, 2017 and Exclusion criteria: 1) articles published in languages other than English, 2) case reports, case series, animal studies, in vitro studies, and letters to the editor, and 3) full-text article unavailable even after writing to the authors. Preliminary screening of 274 studies excluded 223 studies for not meeting the eligibility criteria. Of the remaining 51 studies, 19 were removed for being duplicates. Of the remaining 32 studies, 15 were excluded after reading the abstract. Of the 17 studies that were left, 2 were excluded because they were in a language other than English, and 2 were excluded because the study group did not mention cleft palate patients. Thus, 13 studies providing results for a total of 654 patients were included in this qualitative synthesis. Minimally invasive bone graft harvest techniques are better than the conventional open iliac bone harvest method because they offer shorter operative time, decreased requirement for pain medications, less pain on discharge, and a shorter hospital stay.