• Design & Manufacturing
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• v.18 no.2
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• pp.35-40
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• 2024

Injection molding is a process widely used across various industries for molding plastics, and it is the most commonly applied process in root industries utilizing molds. Among the different types of injection molding, insert injection molding, where busbars are used as inserts, is increasingly being applied in the electric vehicle industry. However, currently, the insert injection molding process is manually performed, with workers placing insert components by hand before injection molding. This results in issues related to productivity, safety, and quality. Additionally, there is a growing demand for automation of such production lines due to hazardous working conditions, economic difficulties in the manufacturing industry, and the decline in the labor force caused by an aging population. This study focuses on the application of an automated system for the insert injection molding process used in electric vehicles. The development of an automated system for the transport and insertion of insert components, as well as the inspection and stacking processes after injection, has resulted in over a 25% improvement in productivity and more than a 27% reduction in defect rates.

• Journal of Sericultural and Entomological Science
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• v.15 no.1
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• pp.37-48
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• 1973

The purpose of this studies is to improve the cohesion of raw silk through various analyses on cocoon drying, cooking, reeling, re-reeling, and on the properties of water. Also we investigated the correlation between silk testing items which we have reached to the following results. 1. Drying of cocoon When cocoons were slowly dried with 100$^{\circ}C$, the results of cohesion became much better. On the other hand, the results were considerably decreased in case the temperature with 115$^{\circ}C$. 2. Cooking of cocoon In case of the cooking of cocoon, we found that the result of cohesion was best with incomplete cooking, that of the control was next, while in over cooking, the results were very low. Also the results of cohesion were much better when using the method of over cooking with sericin arrestive agent than that of incomplete cooking with sericin agglutinating agent. 3. Reeling of cocoon A) When the temperature of reeling bath was 25-45$^{\circ}C$, the results of cohesion test were much better, but at the temperature below 25$^{\circ}C$ or above 45$^{\circ}C$, the results became worse. B) With out the process of croissieur, the results of cohesion were too bad, but in case of croissieur more than 1cm, cohesion became better rapidly. Further more, we understood that the results of cohesion were improving slightly with longer length of croissieur. C) When the velocity of reeling was increased, the results of cohesion also improved. The best results were shown when reeling velocity was 180-220 r.p.m. But when the velocity was increased more than 220 r.p.m., the results of cohesion got worse more or less. D) When the temperature of the drying pipe in reeling machine was raised, the results of cohesion also showed a tendency to improve. 4. Re-reeling A) We could net reach a conclusion as to have correlation between the number of dipping repeat in vacuum tank and the results of cohesion before re-reeling process. B) When we used Seracol 500 as an agglutination protective agent with l/1000 to l/2000 of water, the results of cohesion test were better. C) When we used Pearl-lite as an agglutination protective agent with 1/1000 to 1/2000 of water, the results of cohesion were considerably better. D) We gained tile best results when used Cohesion Improving Chemical, A-80, with 500-1500 times diluted. 1) Results of cohesion was improved when humidity was low or temperature was high in the rereeling machine. 5. Filature water A) The water pH near the isoelectric point of protein showed the best cohesion, but the farther water pH, the worser results were obtained. B) With the increasing of M-alkalinity in filature water, the results of cohesion were worse. Above all, we understood the tendency of the results of cohesion get worse when the M-alkalinity is increased above 200 ppm. C) By increasing the total hardness of the filature water, it improved the results of cohesion. Especially, when the total hardness was above 300ppm, the results were extremely high. 6. Effects combination of each results A) The result of effects combination in filature processes with the obtained best conditions was distinctively improved. But the results could not reach in mathematicaly double effect. When reelied under worse conditions, the results of cohesion test were too bad. There was "effect limit" for the promotion. B) Generally the results of cohesion were bad when the filature conditions(the temperature, pressure and the properties of water, etc) are processed as sericin loss to be high. On the other hand, the results were very good when lower sericin loss was controlled in filature conditions. C) When filature conditions such as reeling velocity and croissieur length provide pysical cohesion ability and when raw silk dry fast during reeling and re-reeling, we found the result of cohesion was better. 7. Correlation of silk testing items. A) A negative correlation exists between the results of cohesion test and cleanness defect. Another word, the result of cohesion test was found to be worse as cleanness defect increased. B) In cleanness, cohesion has negative correlation against the number of slugs, but we could not find any correlation against long loops, loose ends. C) Cohesion has negative correlation against average neatness and low neatness defect. The better the results of neatness respectively, the better the results of cohesion found. D) There is no correlation between tenacity and the results of cohesion test, but there was high positive correlation between the results of elongation and those of cohesion test. The more elongation, the better the results of cohesion was found.

• Journal of the Korean Orthopaedic Association
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• v.54 no.2
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• pp.110-119
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• 2019

Proximal humerus fracture can be defined as a fracture that occurs in the surgical neck or proximal part of the humerus. Despite the appropriate treatment, however, various complications and sequelae can occur, and the treatment is quite difficult often requiring surgical treatment, such as a shoulder replacement. The classification of sequelae after a proximal humerus fracture is most commonly used by Boileau and can be divided into two categories and four types. Category I is an intracapsular impacted fracture that is not accompanied by important distortions between the tuberosities and humeral head. An anatomic prosthesis can be used without greater tuberosity osteotomy. In category I, there are type 1 with cephalic collapse or necrosis with minimal tuberosity malunion and type 2 related to locked dislocation or fracture-dislocation. Category II is an extracapsular dis-impacted fracture with gross distortion between the tuberosities and the humeral head. To perform an anatomic prosthesis, a tuberosity osteotomy should be performed. In category II, there are type 3 with nonunion of the surgical neck and type 4 with severe tuberosity malunion. In type 1, non-constrained arthroplasty (NCA) without a tuberosity osteotomy should be considered as a treatment. On the other hand, reverse shoulder arthroplasty (RSA) should be considered if types 1C or 1D accompanied by valgus or varus deformity or severe fatty degeneration of the rotator cuff. In general, the results are satisfactory when NCA is performed in type 2 sequelae. On the other hand, RSA can be considered as an option when there is no bony defect of the glenoid and a defect of the rotator cuff is accompanied. In type 3, it would be effective to perform internal fixation with a bone wedge graft rather than shoulder replacement arthroplasty. Recent reports on the results of RSA are also increasing. On the other hand, recent reports suggest that good results are obtained with RSA in type 3. In type 4, RSA should be considered as a first option.

• Archives of Plastic Surgery
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• v.34 no.5
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• pp.663-666
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• 2007

Purpose: Autologous fat injection into the facial area is a frequently used technique in aesthetic plastic surgery for augmentation of the soft tissue. Fat injection is a very safe procedure because of the advantage of being autologous tissue. Minimal foreign body reaction or infections are noted after fat injection. However, there may be some complications including those as severe as blindness. There have been some case reports on visual disturbances after autologous fat injection reported in the literature. Methods: A 21-year-old female patient underwent autologous fat injection into left eyebrow area to correct depression of soft tissue. Immediately after injection of autologous fat, she complained sudden visual loss on the left eye. She had come to our emergency room and ophthalmologic evaluation showed that the patient could only recognize hand motion. There was no abnormality of the optic nerve on magnetic resonance imaging. Suspecting an ischemic optic neuritis from fat embolism of the central retinal artery, the patient was treated conservatively with occular massage, antiglaucomatic agent, anti-inflammatory drugs and antibiotics. Visual field examination showed visual defect of half the lower hemisphere. Results: While maintaining antiglaucomatic agents and non steroidal anti inflammatory drugs, fundoscopic examination showed no abnormalities on the second day of admission. Visual field examination showed an improvement on the fourth day along with decreased eyeball pain. Significant improvement of vision was noted and the patient was discharged on the fifth day of admission. The patient was followed-up 2 days afterwards with improved vision and visual field defect. Conclusion: We describe an unusual case of sudden unilateral visual disturbance following autologous fat injection into periorbital area.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.30 no.1
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• pp.43-48
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• 2004

Purpose: Among the various surgical methods used for the effective treatment of cystic lesion in the jaws historically, decompression procedure has some of superior prognosis compare to direct enucleation. In order to propose the efficacy of decompression we performed this retrospective study to compare decompression procedure with one-stage enucleation in clinical results and prognosis. Patients and Methods: We reviewed 175 patients who had been histopathologically diagnosed cystic lesions from 1996 to 2000 in our department. Patients who had been received decompression alone or secondary enucleation after decompression were 31 cases, and enucleation alone were 144 cases. The age and sex of the patients, the area, size, and histological type of the lesions, and detailed operation and complications including recurrence were investigated. The minimal follow-up period was 2 years. Results: In 31cases of decompression, male patients were 22cases(71%) similar to male predilection(62.3%) in total 175 cases. Cystic lesions were developed evenly in all age groups totally. Decompression was mainly performed in teenagers but enucleation was used in elder decades. In decompression cases the lesions were located in mandibular posterior, maxillary posterior, mandibular anterior, and maxillary anterior in order, which had some differences in total and enucleation cases. In enucleation cases, less than 3cm in size was 77.1% but larger than 3cm was 93.5% in decompression cases. Histopathologically, dentigerous cysts(54.8%), unicystic ameloblastomas(16.1%), and odontogenic keratocysts(12.9%) were seen in decompression cases and no recurrence or metaplasia and infection was observed. On the other hand, permanent tooth loss, numbness, recurrence, and so on were accompanied after enucleation. Conclusion: Although decompression procedure has disadvantages such as many of visiting times and slow recovery of the surgical defect, decompression is the best choice of treatment for large cystic lesions of the jaws, because it prevents functional and cosmetic defect, allows bone regeneration, and makes easy secondary enucleation.

• Journal of Periodontal and Implant Science
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• v.30 no.2
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• pp.257-277
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• 2000

New techniques for regenerating the destructed periodontal tissue have been studied for many years. Current acceptable methods of promoting periodontal regeneration are basis of removal of diseased soft tissue, root treatment, guided tissue regeneration, graft materials, and biological mediators. Platelet Rich Plasma has been reported as a biological mediator which regulates activities of wound healing progress including cell proliferation, migration, and metabolism. The purpose of this study is to evaluate the effects of using the Platelet Rich Plasma as a regeneration promoting agent for furcation involvement defect. Five adult beagle dogs were used in this experiment. The dogs were anesthetized with Ketamin HCl(0.1 ml/kg, IV)and Xylazine hydrochloride($Rompun^{(R)}$, Bayer, 0.1 ml/kg, IM) and conventional periodontal prophylaxis were performed with ultrasonic scaler and hand instruments. With intrasulcular and crestal incision, mucoperiosteal flap was elevated. Following decortication with 1/2 high speed round bur, degree II furcation defect was made on mandibular third(P3), forth(P4) and fifth(P5) premolar, and stopping was inserted. After 4 weeks, stopping was removed, and bone graft was performed. Ca-P was grafted in P3(experimental group I), Combination of Ca-P and plasma rich platelet were grafted in P4(experimental group II), and P5 was remained at control group.Systemic antibiotics(gentamicin sulfate)and anlgesics(phenyl butazone) were administrated intramuscular for 2 weeks after surgery. Irrigation with 0.1% Chlorhexidine Gluconate around operate sites was performed during the whole experimental period except one day immediate after surgery. Soft diets were fed through the whole experiment period. After 4, 8 weeks, the animals were sacrificed by perfusion technique. Tissue block was excised including the tooth and prepared for light microscope with Gomori's trichrome staining. At 4 weeks after surgery, there were rapid osteogenesis phenomenon on the defected area of the Platelet Rich Plasma plus Ca-P BBP group and early trabeculation pattern was made with new osteoid tissue produced by activated osteoblast. Bone formation was almost completed to the fornix of furcation by 8 weeks after surgery. In conclusion, Platelet Rich Plasma can promote rapid osteogenesis during healing of periodontalregeneration.

• Journal of Navigation and Port Research
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• v.33 no.10
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• pp.671-678
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• 2009

Recently, there have been some researches in the equipment fault detection based on shock and vibration information. Most research of them is based on shock and vibration monitoring to determine the equipment fault or not. Different with engine fault detection based on shock and vibration information we focus on detection of engine for boat and system control. First, it use the duplicated-checking method for shock and vibration information to determine the engine fault or not. If there is a fault happened, we use the integral to determine the error engine shock wave width and detect the fault area. On the other hand, we use the engine trend analysis and standard of safety engine to implement the shock and vibration information database. Our simulation results show that the probability of engine fault determination is 98% and the probability of engine fault detection is 72%

• Journal of Korean Foot and Ankle Society
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• v.22 no.1
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• pp.21-25
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• 2018

Purpose: To analyze the correlation between a rupture of the hypovascular zone and early single heel raising after Achilles tendon repair. Materials and Methods: From January 2012 to August 2015, 68 patients, who underwent surgical treatment for a Achilles tendon rupture using Krackow method, were analyzed retrospectively. The patients were divided into two groups according to possibility of single heel raises within 3 months postoperatively. During the periodic outpatient observations, the visual analogue scale, Achilles tendon total rupture score (ATRS), and timing capable single heel raises were evaluated. In addition, the preoperative defect size and distance between the calcaneal osteotendinous junction and the rupture site were measured by ultrasound in all cases. Results: Twenty-three patients could perform a single heel raise within 3 months after surgery (early single heel raise group), and fortyfive patients could perform a single heel raise after 3 month postoperatively. The age, gender, body mass index, smoking, and operation delay were similar in the two groups. In addition, the defect size and distance between the calcaneal osteotendinous junction and rupture site as measured by preoperative ultrasound were similar (p=0.379 and p=0.631, respectively). On the other hand, when the rupture site was divided into the hypovascular zone (4~7 cm from calcaneal osteotendinous junction) and non-hypovascular zone, the hypovascular zone rupture rate was significantly lower in the early single heel raise group (60.9%, 14/23; 91.1%, 41/45; p=0.003). In logistic regression analysis, the odds of the hypovascular zone rupture group being capable of early single heel raise were 0.189 (p=0.017). The ATRS score at 3 months and 1 year after surgery were significantly higher in the early single heel raise group (p<0.001). Conclusion: Achilles tendon rupture at the hypovascular zone is a poor prognostic factor for early single heel raise and might affect the prognosis significantly after an Achilles tendon rupture operation.

• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.6
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• pp.433-438
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• 1999

Magneto-acoustic emission (MAE) energy and hardness were measured in the reactor pressure vessel steel (SA508 Steel) for the various neutron fluence, irradiated dose up to $10^{18}n/cm^2$. The hardness was nearly a constant up to $10^{16}n/cm^2$, but it was rapidly increased with an increase of the neutron irradiation above $10^{17}n/cm^2$. It may be considered that the increase of hardness is due to the hindrance of dislocation motion induced defect clusters by irradiation. On the other hand. the MAE energy was slowly decreased as the neutron irradiation increased up to $10^{16}n/cm^2$ and it was rapidly decreased with an increase of the neutron irradiation above $10^{17}n/cm^2$. The decrease of the MAE energy may be considered as an increase of the defect clusters which is very sensitive to the $90^{\circ}$ domain wall motion. Furthermore, the change of MAE energy and hardness had nearly a linear relationship. but the change of MAE energy was more significant than the change of the hardness. Therefore, MAE may be considered as a very useful technique for the nondestructive evaluation of irradiation damage.

• Korean Journal of Construction Engineering and Management
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• v.8 no.5
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• pp.101-108
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• 2007

To execute a construction project, many construction participants are engaged in the project. Especially many subcontactors role is very important, but their contract statute seems weaker rather than prime contractor. So to protect the subcontractor and to activate fair subcontract, Fair Transactions in Subcontracting Act was enacted. Direct payment to subcontractor clause of the act can protect subcontractor from the fear of insolvency of prime contractor, on the other hand can cause dispute about the interpretation of defect liability. Therefore the positive act and regulation were examined, and the effects of direct payment to subcontractor were analyzed. And the treatment direction of direct payment were suggested in this paper. Summary is as follows; (1) Statute of subcontractor for the ordering subject must be considered (2) Contract relationship must be reflected in the performance bond, subcontract bond, and subcontract construction conditions (3) To clarify the defect liability for the direct payment, retainage to guarantee the repair during contract period may be reflect on the subcontract construction conditions.