• The Korean Journal of Applied Statistics
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• v.17 no.2
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• pp.253-267
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• 2004

In some clinical trials, one may see that a significant fraction of patients are cured and their original disease does not recur even after termination of treatment and pro-longed follow-up. This situation occurs frequently in pediatric cancer trials where there are excellent therapeutic results. In such cases, interest concentrated on the difference of cure rates rather than other types of differences in failure distributions. Various authors have investigated the parametric and nonparametric methods for testing the difference of cure rates. In this study, we compare by simulation the power and size of a parametric test and five nonparametric tests in a various range of the alternatives, censoring rates and cure rates. Our objectives are to determine if any test was preferable on the basis of size and power in various situation, and to investigate the effect of the model misspecification.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.12
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• pp.7-14
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• 2019

A marine turning gear controls the position of the piston-crank mechanism by rotating the flywheel of the marine engine at a low speed, which is the main auxiliary machine that enables the disassembly and maintenance of the engine. In this study, the safety factor for surface durability and tooth bending strength was improved by the design modification of the marine turning gear based on the spur planetary gear. Angular velocity, torque, and efficiency of the turning gear were measured using a reliability evaluation tester, and a multibody dynamics model for analysis corresponding to the test results was developed. Finally, it was confirmed that the design improvements improved the tooth surface damage of the sun gear in the 3^rd reduction stage.

• Radiation Oncology Journal
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• v.35 no.1
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• pp.1-15
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• 2017

Locoregional failure is the most frequent pattern of failure in locally advanced head and neck cancer patients and it leads to death in most of the patients. Second primary tumors occurring in the other head and neck region reach up to almost 40% of long-term survivors. Recommended and preferred retreatment option in operable patients is salvage surgical resection, reporting a 5-year overall survival of up to 40%. However, because of tumor location, extent, and underlying comorbidities, salvage surgery is often limited and compromised by incomplete resection. Reirradiation with or without combined chemotherapy is an appropriate option for unresectable recurrence. Reirradiation is carefully considered with a case-by-case basis. Reirradiation protocol enrollment is highly encouraged prior to committing patient to an aggressive therapy. Radiation doses greater than 60 Gy are usually recommended for successful salvage. Despite recent technical improvement in intensity-modulated radiotherapy (IMRT), the use of concurrent chemotherapy, and the emergence of molecularly targeted agents, careful patient selection remain as the most paramount factor in reirradiation. Tumors that recur or persist despite aggressive prior chemoradiation therapy imply the presence of chemoradio-resistant clonogens. Treatment protocols that combine novel targeted radiosensitizing agents with conformal high precision radiation are required to overcome the resistance while minimizing toxicity. Recent large number of data showed that IMRT may provide better locoregional control with acceptable acute or chronic morbidities. However, additional prospective studies are required before a definitive conclusion can be drawn on safety and effectiveness of IMRT.

• Agricultural and Biosystems Engineering
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• v.5 no.2
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• pp.45-49
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• 2004

Objective of the study was to develop a garlic clove metering device. The metering device consisted of a drum, a bucket and a bucket cover. A garlic clove simulator was designed to simulate motions of garlic cloves in the metering device. Simulation was performed using a multibody dynamic analysis program, RecurDyn version 5.1. Physical properties of garlic cloves such as mass and center of gravity were determined using 3D CAD modeler, IDEAS version 10.0. In order to compare the results of the simulation with actual movement of a garlic, movement of garlic clove was photographed by a high speed camera. A prototype metering device was built and tested under various metering speeds and metering guide angles. At the 12 rpm metering speed, rate of single-clove-discharge was $90.0\%$ and missing rate $1.3\%$ at $5^{\circ}$.

• Journal of Biosystems Engineering
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• v.32 no.2 s.121
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• pp.69-76
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• 2007

This study was conducted to evaluate the sideways overturning stability of side loaded mini-forwarder. The model of a prototype was developed using a 3D CAD modeler and the performance was experimentally validated. The prototype model was run on the multibody dynamic analysis program, RecurDyn 6.0, to simulate motions when the model traversed over a circular bump on a inclined ground surface. The simulation was performed at a constant forward speed of 1.85 km/h under the loaded and unloaded conditions. The forward direction was also controlled to vary from 0 to 360 degrees with an increment of 10 degrees. Results of the simulation showed safe regions in which the mini forwarder could travel safely in terms of direction and slope of the ground. Even when the mini-forwarder was loaded by 20 logs of 3.6 m long and 12 cm diameter, it traveled safely within the ground slopes of 1 to 45 degrees by directions.

• Clinics in Shoulder and Elbow
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• v.3 no.1
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• pp.44-48
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• 2000

Weaver-Dunn's operation for acromioclavicular injury yields satisfactory results in most cases. Although clavicular prominence can recur, it is not frequently symtomatic, but it can cause serious impairment of shoulder function in young and active patients. The authors performed reconstruction of coracoclavicular ligament with an autogenous hamstring tendon graft in a 31 years old electrician with recurrence of clavicular prominence accompanied by pain and limitation of overhead activity. The hamstring tendon and two coracoclavicular sutures looped under the coracoid process were passed through holes in the clavicle and around the clavicle in overreduced position. Even though clavicular prominence recurred somewhat, the modified UCLA score by Rockwood improved to 17 from 11/20 at 2 years after operation and the patient had no restriction in working as an electrician. Symptomatic patient with recurrent clavicular prominence after Weaver-Dunn's operation can benefit from reconstruction of coracoclavicular ligament with a hamstring tendon.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.1
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• pp.115-123
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• 2020

Objectives The aim of this study was to investigate the effects of liver-tonification acupuncture (LTA) on periodic muscle cramps (MC). Methods We retrospectively reviewed medical records of 28 patients treated for periodic MC with LTA in a Korean medicine clinic. Patients were treated with (A) LTA alone, (B) LTA and treatments for myofascial meridian, or (C) LTA and treatments for other diseases. We mainly investigated effectiveness of treatments, the number of treatments, the number of relapses, and time to relapse. Results After treatments, periodic MC disappeared in all patients except two in group C. The number of treatments in group C was significantly greater than that of group A (p<0.05). Periodic MC recurred in one patient in each of groups A and C, but symptoms disappeared after re-treatments. Periodic MC did not recur for a median of 7.0, 8.5, and 5.0 weeks in groups A, B, and C, respectively. Conclusions We found some therapeutic effects of LTA treatments for periodic MC in middle-aged and elderly patients.

• Archives of Craniofacial Surgery
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• v.18 no.3
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• pp.197-201
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• 2017

Maxillary sinus mucocele can occur due to many medical factors such as chronic infection, allergic sinonasal disease, trauma, and previous surgery. However, it occurs mainly after Caldwell-Luc operation, usually more than 10 years after surgery. There are a few cases of maxillary sinus mucocele with ocular symptoms. Also, a case causing ocular symptoms because of invasion to the orbital floor is rare. Therefore, we report a case of a 55-year-old male patient who underwent Caldwell-Luc operation about 30 years ago. Then, symptoms such as exophthalmos, diplopia, and visual disturbance developed suddenly 3 months prior to admission. Computed tomography showed a cyst invading the orbital floor which resulted in eyeball deviation. The orbital floor defect measured approximately $2.5{\times}3.3cm$. Maxillary sinus mucocele was removed through an endoscopic approach. After this, we reconstructed the orbital floor through a subciliary incision. Observation was carried out after three years, and ocular symptoms such as diplopia and exophthalmos did not recur.

• Journal of Aerospace System Engineering
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• v.14 no.4
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• pp.10-17
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• 2020

When an aircraft is taxiing, excitation force is applied according to the shape of the road surface. The sprung mass acceleration caused by the excitation of the road surface negatively affects the feeling of boarding. This paper addresses the verification process of the semi-active control method applied to improve the feeling of boarding. The Magneto-Rheological damper landing gear model is employed alongside the control method. It is a Oleo-Pneumatic damper filled with a fluid having the characteristics of increasing yield stress when subjected to a magnetic field. The control method involves verifying Skyhook Control Type2 developed by Skyhook control. The Sinozuka white noise model that considers runway characteristics was employed for the road surface in the simulation. The runway road surface obtained through this model has stochastic characteristics, so the dynamic characteristics were analyzed by applying Monte-Carlo simulation. A dynamic analysis was conducted by co-simulating the landing gear model made by RecurDyn and the control method designed by Simulink. Simulation results show that the Skyhook Control Type2 method has the best control effect in the low speed range compared to the passive type (without control) and skyhook control.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.28 no.5
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• pp.390-394
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• 2002

Basal cell adenocarcinoma is an epithelial neoplasm which is cytologically and histomorphologically similar to basal cell adenoma but is different because of the infilitrative growth. This tumor, a rare salivary gland tumor newly classified as basal cell adenocarcinoma by the WHO in 1991, is infiltrative, locally destructive and tends to recur but metastasis is less common. The differential diagnosis includes basal cell adenoma, adenoid cystic carcinoma, and basaloid squamous carcinoma. Nearly 90 percent of these tumors occurr in the parotid gland and can be classified into low grade carcinomas with a relative good prognosis. Basal cell adenocarcinoma of minor salivary gland is very rare and has a less favorable clinical course compared with that of the major salivary glands. This is a case of basal cell adenocarcinoma occurring at the minor salivary gland of the soft palate. We treated this patient with block excision and adjunctive radiation therapy.