• Design & Manufacturing
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• 제17권3호
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• pp.15-20
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• 2023

In the fine blanking process, which is a press operation known for producing parts with narrow clearances and high precision through the application of high pressure, die roll often occurs during the shearing process when the punch penetrates the material. This die roll phenomenon can significantly reduce the functional surface of the parts, leading to decreased product performance, strength, and fatigue life. In this research, we conducted an in-depth analysis of the factors influencing die roll in the curvature area of the fine blanking process and identified its root causes. Subsequently, we designed and experimentally verified a die roll reduction process specifically tailored for the door latch manufacturing process. Our findings indicate that die roll tends to increase as the curvature radius decreases, primarily due to the heightened bending moment resulting from reduced shape width-length. Additionally, die roll is triggered by the absorption of initial punch energy by scrap material during the early shearing phase, resulting in lower speed compared to the product area. To mitigate the occurrence of die roll, we strategically selected the Shaving process and carefully determined the shaving direction and clearance area length. Our experiments demonstrated a promising trend of up to 75% reduction in die roll when applying the Shaving process in the opposite direction of pre-cutting, with the minimum die roll observed at a clearance area length of 0.2 mm. Furthermore, we successfully implemented this approach in the production of door latch products, confirming a significant reduction in die roll. This research contributes valuable insights and practical solutions for addressing die roll issues in fine blanking processes.

• 전기학회논문지
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• 제63권9호
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• pp.1199-1205
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• 2014

A power system configuration has been increasingly advanced with a number of generating units. In particular, renewable energy resources are widely introduced due to the environmental issues. When applying the renewable energy sources with the ESS (Energy Storage System), the ESS is the role of a potential generating resource in the power system while mitigating the output volatility of renewable energy resources. Thus, for applications of the ESS, the surrounding environment of it should be considered, which means that capacity and energy of the ESS can be affected. Moreover, operation strategy of the ESS should be proposed according to the installation purpose as well as the surrounding environment. In the paper, operation strategy of the ESS is proposed considering load demand and the output of renewable energy resources on a hourly basis. Then, the cost of electrical energy is minimized based on the economic model that consists of capital cost, operation cost, fuel cost, and grid cost for a year. It is sure that peak-shaving effects can be achieved while satisfying the minimum cost of electrical energy.

• Archives of Plastic Surgery
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• 제33권2호
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• pp.259-262
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• 2006

Fibrous dysplasia(FD) of the bone is a slowly progressive, benign disease of unknown cause where normal architectures are replaced with fibrous and osteoid tissue. FD of the maxilla usually manifests as a bony enlargement with painless swelling and bone deformity, contouring to facial asymmetry. The lesion may involve the nasal fossae, orbits, or alveolus bone, causing diverse functional disturbance. Treatment options range from shaving to total maxillectomy and reconstruction depending on the presenting symptoms. Shaving, partial maxillectomy and maxillary sinus formation was performed in 5 patients with fibrous dysplasia in the past 2 years. Follow up period ranged from 1 month to 11 months. Aesthetic appearance, CT findings, and relief from symptoms were compared. In all patients, facial asymmetry was restored to symmetry and nasal obstructive symptoms were improved. With this procedure, expansion of the lesion will be controlled until puberty, preventing the development of new functional disturbances. After puberty, no further treatment can be anticipated due to the growth arrest inherent to the disease.

• Annals of Geriatric Medicine and Research
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• 제22권4호
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• pp.204-207
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• 2018

Mycobacterium abscessus comprises rapidly growing mycobacteria, and the clinical manifestations of M. abscessus skin infection include papule, nodule, ulcer, scar and mixed form. The cutaneous infections have been reported due to minor trauma, cosmetic therapy, acupuncture and disseminated infection. A 75-year-old man presented with pruritic diffuse various sized erythematous papuloplaques and pustules on the neck and chest for 2 months. The cutaneous lesions were spread around the wound of the shaving on the neck. The histopathologic findings were consistent with abscess showing infiltrations of neutrophils and lymphocytes in the dermis and negative findings were observed on immunohistochemical stain including acid-fast bacilli stain. One month later, mycobacterial culture result showed positive findings, and the pathogen was identified by reversetranscriptase polymerase chain reaction with hybridization. The patient was treated with combination of clarithromycin and ethambutol for 5 months and there is no evidence of recurrence after 6 months of follow-up. Herein, we report a case of M. abscessus cutaneous infection through minor trauma caused by shaving in the elderly.

• 대한관절경학회지
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• 제10권2호
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• pp.153-158
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• 2006

목적: 관절경적 후내측 도달법을 이용한 밸브기전의 교정을 통한 슬와 낭종의 절삭 절제술의 임상적 결과와 그 유용성을 보고 하고자 한다. 대상 및 방법: 2004년 4월부터 2005년 6월까지 변형된 관절경적 방법으로 슬와 낭종을 치료하였던 15례를 대상으로 하였다. 평균추시 기간은 15개월(범위: $12{\sim}28$) 이었다. Rauschning과 Lindgren의 평가 기준을 근거로 예후를 판정하였으며, 수술에 소요된 시간과, 슬관절의 통증이 없어지고 완전한 운동범위를 얻는데 걸린 기간을 측정하였다. 수술 후 12개월에 초음파를 시행하여 재발 여부를 관찰하였다. 결과: 기능평가는 Rauschning 과 Lindgren의 기준으로 최종 추시시 전례에서 Grade 0 또는 Grade 1 이었다. 수술 시간은 평균 45분(범위 $35{\sim}70$) 이었다. 전례에서 수술 후 5일 이내에 통증 없는 슬관절 운동범위의 완전한 회복을 얻을 수 있었으며, 1년 이상의 최종 추시에서도 운동범위는 모두 정상이었다. 재발한 예는 없었고, 통증과 보행 장애도 없었다. 결론: 후내측 도달법을 이용한 관절경술은 낭 주름의 밸브기전을 쉽게 교정할 수 있고, 슬와 낭종의 절삭술을 효과적으로 시행할 수 있는 대치방법으로 사료된다.

• 전기전자학회논문지
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• 제25권2호
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• pp.388-398
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• 2021

본 논문에서는 전기요금 절감용 ESS를 활용한 Particle swarm optimization(PSO) 기반 Peak shaving 제어 방법을 제안한다. 제안한 방식은 실제 부하와 예상되는 부하의 소비를 비교하여 피크 절감을 위해 ESS의 추가 유효전력값을 계산하여 입력을 더한다. 또한 추가로 증가시킨 유효전력을 보상하기 위해, 유효전력을 할당하는 과정을 수행하며 유효전력 할당치가 피크 부하에 영향을 주지 않도록 유효전력 할당 지점에 예상되는 부하의 평균을 최소화하는 최적화 해를 PSO를 통해 찾는다. 제안한 방식의 성능 검증을 위해 실제 부하 데이터와 예측 알고리즘을 반영하여 예측 오차가 적은 경우와 큰 경우의 사례 연구를 수행하였다. 사례 연구 수행 결과 제안한 방식을 전기요금 절감을 위한 충·방전 제어 방식과 같이 수행한 경우 예측 오차가 큰 경우에도 성공적으로 피크 부하 절감을 수행하였으며, 17.8%의 피크 부하 절감 효과와 6.02%의 전기요금 절감 효과를 보였다.

• 대한치과의사협회지
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• 제50권11호
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• pp.677-681
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• 2012

Orthognathic surgery(2-jaw or 1-jaw surgery) is very famous one of cosmetic techniques. However, primary purpose of orthognathic surgery is to improve the occlusion of jaw and secondary purpose is to improve the esthetic result. Unfortunately, many patients don't only confuse often primary and secondary purpose of orthognathic surgery but they think the esthetic result is more important than the occlusion. Therefore, oral and maxillofacial surgeon has to fully understand cosmetic needs of patient and reflect that in the treatment plan. Patients with prominent mandibular angle want to have the narrower face of so called 'V-line' shape. Various techniques like the angle shaving, ostectomy of the lateral cortex around the mandibular angle and masseter musclectomy can be used for improving the mandibular angle hypertrophy. These techniques also can be applied in orthognathic surgery at the same time. We operated patients of orthognathic surgery, especially, with wide lower face and post-operative results were satisfactory in all cases. So, we propose mandibular angle management for improving the esthetic result of orthognathic surgery.

• 전기학회논문지
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• 제64권7호
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• pp.1125-1129
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• 2015

Increasing peak load is one of the major concerns about operation of urban railroad systems. Since ESSs (Energy Storage Systems) have a great potential for shaving the peak load, there has been a growing interest in the use of ESS for peak load reduction. Also, ESS can be optimally scheduled to minimize the electricity purchasing cost under a given ToU (Time-of-Use) tariff by taking advantage of electricity price difference between peak and off-peak time. This paper presents a Mixed Integer Programming (MIP)-based ESS scheduling method to minimize the electricity purchasing cost under a ToU tariff for an urban railroad system.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.307-310
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• 2001

The hair-growth effect of Illite was suggested by some people who were using Illite as a beautifying material. We investigated the hair-growth effect of Illite powder. The hair-growth effects were investigated by two methods; the activity of hair-growth after shaving the hairs on the black mouse (C57BL/6) and the recovery activity of hair-growth after hair-loss induced by cyclophosphamide treatment. Suspension of Illite powder was applied to the back of the black mouse by method of skin paste. Illite promoted significantly the hair growth of mouse in both conditions of shaving and hair-loss. And then we investigated the toxicity which may be induced by Illite when it was administrated orally as a single dose. We could not fond out any significant toxicity induced by single dose oral administration of Illite.

• 대한전기학회논문지
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• 제36권2호
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• pp.73-79
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• 1987

This paper describes a new algorithm to evaluate the production cost for a generation system including energy-limited hydroelectric plants. The algorithm is based upon the analytical production costing model developed under the assumption of Gaussian probabilistic distribution of random load fluctuations and plant outages. Hydro operation and pumped storage operation have been dealt with in the previous papers using the concept of peak-shaving operation. In this paper, the hydro problem is solved by using a new version of the gradient projection method that treats the upper / lower bounds of variables saparately and uses a specified initial active constraint set. Accuracy and validity of the algorithm are demonstrated by comparing the result with that of the peak-shaving model.