• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1052-1065
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• 2024

Advanced Pressurized Water Reactors (APWRs) and Boiling Water Reactors (BWRs) employ a suppression pool as a heat sink to prevent containment overpressure. Steam can be discharged into the pool through multi-hole spargers or blowdown pipes in both normal and accident conditions. Direct Contact Condensation (DCC) creates sources of momentum and heat. The competition between these two sources determines the development of thermal stratification or mixing of the pool. Thermal stratification is of safety concern as it reduces the cooling capability compared to a completely mixed pool condition. In this work we develop a scaling approach to prediction of the thermal stratification in a water pool induced by steam injection through spargers. Experimental data obtained from large-scale pool tests conducted in the PPOOLEX and PANDA facilities, as well as simulation results obtained using validated codes are used to develop the scaling. Two injection orientations, namely radial injection through multi-hole Sparger Head (SH) and vertical injection through Load Reduction Ring (LRR), are considered. We show that the erosion rate of the cold layer can be estimated using the Richardson number. In this work, scaling laws are proposed to estimate both the (i) transient erosion velocity and (ii) the stable position of the thermocline. These scaling laws are then implemented into a 1D model to simulate the thermal behavior of the pool during steam injection through the sparger.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.4
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• pp.324-331
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• 2010

The radial forearm free flap (RFFF) has become a workhorse flap as a means of reconstructing surgical defects in the head and neck region. We have transferred 12 RFFFs with fasciocutaneous type on oral cavity defects in 12 patients after cancer resection and submucous fibrotic lesion ablation from 2005 to 2007 at Department of oral and maxillofacial surgery, Pusan National University Hospital. We reviewed retrospectively patients' charts and followed up the patients. Clinical analysis on the cases with RFFFs focusing on flap morbidity, indications and available vessels was done. The results of study are follows: 1. RFFF could be applied for all kind of defects after resection of tongue, floor of mouth, buccal mucosa, denuded bone of palate, maxilla, and mandible. 2. All free flaps could be used for primary reconstruction. The survival rate of 12 RFFFs was 92%. Partial marginal loss of the flaps was shown as 3 cases among 12 cases. Large size-vessels like superior thyroid artery, facial artery, internal jugular vein were favorable for microvascular anastomosis. 3. Parenteral nutrition instead of nasal L-tube also can be favorable for postoperative a week for better healing of the flap if the patients couldn't be tolerable with nasal tubing. 4. Donor sites with thigh skin graft were repaired with wrist band for 2 weeks. The complications included scarring, abnormal sensation on hand, and reduced grip strength in few patients, but those didn't induce major side effects. 5. Most RFFFs were well healed even if mortality rate of cancer patients was shown as 50% (5/10 persons). The mortality of patients was not correlated with morbidity of the flaps. We could identify the usefulness of RFFF for restoration of oral function, esthetics if the flap design, tissue transfer indications, and well controlled operation are proceeded.

• International Journal of Automotive Technology
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• v.6 no.6
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• pp.555-561
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• 2005

This experimental study was executed to obtain basic data for actual engine operation using radical induced ignition method (RI) which can achieve emission reduction and high efficiency due to the rapid bulk combustion. In this study, a direct injection diesel engine was converted into SI type engine with a sparkplug. The modified SI type engine can be divided into two classes. One is the SI engine with a sparkplug only at the cylinder head, and the other is the SI engine with the sparkplug which is enveloped in a sub-chamber. Also, a basic experimental was conducted in order to investigate combustion mechanism of radical induced injection before the experiment execution for actual engine using the modified SI engine. The bulk combustion phenomenon of radical induced ignition method was analyzed from the basic experiment by using a constant volume chamber. Volume value of sub-chamber used in this experiment is approximately $0.2\%$ of one of the main combustion chamber. In this paper, combustion characteristics using radical induced injection method was compared with that of using spark ignition method according to change in the engine speed and equivalence ratio. As a result, in the case of the radical induced injection engine, the combustion duration and cycle variation were respectively reduced ranged from $\Phi$(equivalence ratio)=0.8 (lean mixture ratio) to $\Phi$=1.0 (stoichiometric ratio).

• Journal of Electrical Engineering and Technology
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• v.12 no.6
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• pp.2388-2398
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• 2017

In this study, we propose a robust face recognition system to pose variations based on automatic pose estimation. Radial basis function neural network is applied as one of the functional components of the overall face recognition system. The proposed system consists of preprocessing and recognition modules to provide a solution to pose variation and high-dimensional pattern recognition problems. In the preprocessing part, principal component analysis (PCA) and 2-dimensional 2-directional PCA ($(2D)^2$ PCA) are applied. These functional modules are useful in reducing dimensionality of the feature space. The proposed RBFNNs architecture consists of three functional modules such as condition, conclusion and inference phase realized in terms of fuzzy "if-then" rules. In the condition phase of fuzzy rules, the input space is partitioned with the use of fuzzy clustering realized by the Fuzzy C-Means (FCM) algorithm. In conclusion phase of rules, the connections (weights) are realized through four types of polynomials such as constant, linear, quadratic and modified quadratic. The coefficients of the RBFNNs model are obtained by fuzzy inference method constituting the inference phase of fuzzy rules. The essential design parameters (such as the number of nodes, and fuzzification coefficient) of the networks are optimized with the aid of Particle Swarm Optimization (PSO). Experimental results completed on standard face database -Honda/UCSD, Cambridge Head pose, and IC&CI databases demonstrate the effectiveness and efficiency of face recognition system compared with other studies.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.15-18
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• 2011

Purpose: The anterior iliac crest is a common source for autologous cancellous bone graft. For patients who have previously received cancellous bone grafts from bilateral anterior iliac crests, there may be concerns of whether a sufficient quantity of autologous cancellous bone remains for additional grafts without harvesting it from other sites, such as the posterior iliac crest. Methods: We experienced 3 cases of reharvesting in 2 patients. The diagnosis of the first patient was bilateral facial cleft number 3. This patient received bilateral side cleft alveoloplasty with corticocancellous bone graft from the both anterior iliac crest respectively by a previous surgeon. This patient then needed reharvesting of the anterior iliac crest cancellous bone to correct an ongoing skeletal problem for the bilateral cleft. The other patient had bilateral incomplete cleft of the primary palate. This patient received left side cleft alveoloplasty with cancellous bone graft from the right anterior iliac crest. Before the patient could receive the alveoloplasty on the other side, a radial head osteotomy and cancellous bone graft was performed by orthopedic surgeons who then used the remaining left iliac crest in order to treat a pulled elbow. For the completion of the right side cleft alveoplasty, the anterior iliac crest cancellous bone needed to be reharvested. Prior to the reharvesting, a preoperative computed tomography scan of the pelvis was obtained to assess the maturity of the donor site regeneration. The grafts were then taken from site where a greater amount of regeneration was evident. Results: Long term follow ups showed that the grafts were successfully taken. This sufficient volume was obtainable 14 months after the first harvest. Conclusion: Satisfactory results were achieved after the reharvesting of iliac cancellous bone. Thus, it appears that the reharvesting of the iliac bone is a possible alternative to multiple site grafting, use of allograft or bone substitute materials.

• Journal of Veterinary Clinics
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• v.11 no.1
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• pp.369-376
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• 1994

The purpose of this report Is to discribe the radiological findings of traumatic elbow luxation and subluxation of carpal joint which were caused by being hit by a wild animal and forced hyperextension of carpus in two hunting dogs. In case 1, carniocaudal and mediolateral radiographic examination of the elbow joint revealed that the radius that the radius and ulna were completely luxated laterally. The lateral projection showed the humeral condyles overlying the radial head with an absent joint space, but displacement is apparent on the craniocaudal projection. Incidence of collateral ligament rupture in conjunction with elbow luxation was not recognized on physical examination of the limb after closed reduction. Radiographic examination of the elbow made 5 months after closed reduction revealed only mild degenerative joint disease. Radiographic examination of the carpus in case 2 demonstrated palmar subluxation of most carpal joints including antebrachiocarpal, mediocarpal carpometacarpal joints, and some intercarpal joints, and avulsion fracture of the palmar surface of the accessory carpal bone. However, the mediocarpal and carpometacarpal joints were most severely affected by tensile forces of hyperextension, and it was concluded that the ligaments of the middle ca,pal joints and carpometacarpal joints as well as the palmar fibrocartilage were ruptured based on clinical and radiographic findings. In elbow luxation and subluxation of carpal Joints of the dog, differentiation of the joint or joints involved, and ligamentous structures damaged is important in determining whether surgery Is necessary and which procedure is most appropriate. And the radiographic findings of these conditions would be of help to practitioners.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.4
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• pp.70-75
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• 2006

The performance of a turbopump system composed of an inducer, an impeller, a volute and seals has been computationally analyzed. To save the computational time, only one flow passage of the inducer and impeller is considered for the computations. A steady mixing-plane method is used on the impeller/volute interface for simulating the unsteady interaction phenomena. The axial thrust is predicted from the turbopump calculation in its entirety, which is necessary for such estimation. Moreover, the effects of each component on the pump performance are investigated at a design condition through the analysis of flow structures. The predicted performance is in good agreement with experimental data in terms of head rise, efficiency and volute wall pressure distributions despite of highly complex flow structures being present. The computational results also show that the axial and radial thrusts are within the design limit although corresponding experimental measurements were not taken.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.2
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• pp.188-193
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• 2021

On March 13, 2018 two postflexion larval specimens (18.28 mm and 16.80 mm in standard length) belonging to the family Cryptacanthodidae, suborder Zoarcoidei were collected from Sokcho and Gangneung in Gangwon Province. The family Cryptacanthodidae comprises 4 species worldwide: 3 in the North Pacific Ocean and 1 in the western North Atlantic Ocean. As a result of analyzing 620 bp of the mtDNA COI region, the two postflexion larvae collected in this study were identified as Cryptacanthodes bergi by 99.5% agreement with C. bergi adult registered in NCBI. Postflexion larvae of C. bergi are compressed with large eyes and radial pectoral fins and the anus located in front of the center of the body. Melanophores were intensively distributed along the dorsal midline, except for caudal peduncle, and sporadically distributed on the back of the anus. In addition, there were limited star-like melanophores on the back of the gut. This species showed 0.058 genetic distance when compared mtDNA COI region of C. aleutensis, and it was well distinguished in the distribution pattern of black vesicles of the head, count and measurement traits. Considering the morphological and ecological characteristics of this species, we suggest a new Korean name, " Gwisin-jang-gaeng-i ".

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.159-166
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• 2009

Purpose: We wanted to evaluate the surgical results of early mobilization after rigid fixation of small coronoid fracture using the tension band technique Materials and Methods: Eight cases of coronoid fracture were fixed with the tension band technique and using K-wire and wire through the medial approach. All the cases were Regan-Morrey type 2. According to O'Driscoll, they were classified as 5 cases of the tip type (subtype 2) and 3 cases of the anteromedial type (1 case of subtype 2, and 2 case of subtype 3). The associated collateral ligament injuries (6 cases) and radial head/neck fractures (4 cases) were managed simultaneously. After immobilization for 5~7 days, active ROM exercise with a fitted hinge brace started and continued till postoperative 6 weeks. The patients were assessed for pain, ROM and functional disability using the Mayo elbow performance score (MEPS) at an average of 11 months (range: 6~28 months). The ulnar nerve symptoms were also investigated. Results: We observed solid union in all the coronoid fractures without hardware failure. An average of 2.2 wires (range: 2~4) were used. The mean extension was $3^{\circ}$(range: $0^{\circ}\sim25^{\circ}$), the mean flexion was $137^{\circ}$(range: $130^{\circ}\sim140^{\circ}$), the mean pronation was $69^{\circ}$(range: $45^{\circ}\sim90^{\circ}$) and the mean supination was $78^{\circ}$(range: $45^{\circ}\sim90^{\circ}$). The mean MEPS was 96 (range: 65~100). Ulnar nerve symptoms occurred at postoperative one day and persisted in one patient with the terrible triad of taking radial head excision and residual medial instability. Conclusion: The tension band technique uses easily obtained, economic K-wires and the wire was strong enough to permit early elbow ROM exercise and the technique might improve the elbow function. It was especially useful for fixation of multiple small fragments.

• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.167-183
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• 1987

The anatomical structure of the Skeleton of thoracic limb of thirty-one adult Korean native goats(body weight: 14~17kg) was observed after skeletal preparation, and the osteometry was performed in each bone. The results were as follows; 1. The thoracic limb of the Korean native goat was composed of scapula, humerus, radius, ulna, carpal bones, metacarpal bones, phalanges and sesamoid bones. 2. The scapula was flat and triangular in shape. There were no distinct tuber of spine and acromion in the spine. The subscapular fossa was deep and triangular in shape and the vertebral border was sigmoid form. The coracoid bone was formed as the coracoid process at the medial aspect of the supraglenoid tubercle but the clavicle wa.s not observed. The left and right scapular indexes were 57.92 and 58.31 and the glenoid cavity indexes were 89.23 and 86.82, respectively. 3. The greater tubercle of the humerus was devided into cranial and caudal parts. The third tubercle was observed and the face for the infraspinatus muscle was rectangular form. The left and right humerus indexes were 32.44 and 32.63, the head indexes were 94.13, 96.62 and the trochlear-epidondyle indexes were 67.32 and 65.81, respectively. 4. The radius and ulna were fused entirely except at the broad proximal and narrow distal interosseous spaces. The ulna was longer than the radius, and its reduced body and distal end were fused at the caudomedial surface of the radius. 5. The carpal bones were six in number. There were radial, intermediate, ulnar, accessory, second-third and fourth carpal hones in carpal bones. 6. The metacarpal bone was composed of a large metacarpal bone resulted from the fusion of the third and fourth metacarpal bones, and there was a metacarpal tubercle at the dorsolateral part of the proximal end. There were no vestiges of the second and fifth metacarpal bones. 7. The digits were composed of third and fourth digits and each digit was composed of the proximal, middle and distal phalanges. 8. The sesamoid bones were six in number. There were two at the fetlock joint and one at the coffine joint palmarly in each digit. 9. The ratios of the lengths among the scapula, humerus, antebrachium and metacarpal bone were 1.42 : 1.47 : 1.77 : 1.00 in the left and 1.42 : 1.45 : 1.77 : 1.00 in the right, respectively.