• 산업기술연구
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• 제22권A호
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• pp.43-48
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• 2002

Acoustic modes of a vehicle compartment dominate the noise characteristics of the vehicle system in the low frequency range. Vehicle compartments have head liner and air gap of proper thickness to mount a interior lamp, as well as to have a good sound insulation and absorption performance. This study estimates the acoustic modal property of the medium size passenger car by experiment and by finite element analysis and also, investigates the effect of the head liner on the acoustic mode of the passenger compartment to obtain useful information for low noise compartment design.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.451-454
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• 2007

This paper presents the pattern characteristic using the electrostatic drop-on-demand ink-jet printing system. In order to achieve the pattern characteristic of electrostatic inkjet printing, the capillary inkjet head system is fabricated using capillary tube, Pt wire and electrode, and is packaged by acrylic board for the accurate alignment between wire and electrode-hole. The applied DC voltage of 1.4 $\sim$ 2.0 kV used for the observation of electrostatic droplet ejection. Electrostatic droplet ejection is directly observed using a high-speed camera. For investigated pattern characteristic, conductive inkjet silver ink used. The higher voltage has a good condition which has micro dripping mode. Also, the droplet size decreases with increasing the supplied DC voltage. This paper shows the pattern which is formed by about 300um. Also, capillary inkjet head system will be applied industrial area comparing conventional electrostatic inkjet head system.

• 한국자동차공학회논문집
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• 제8권5호
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• pp.121-128
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• 2000

Simple design methods were developed to control the coolant flow rates through cylinder head gasket holes. Applying the concept of flow through an obstruction the ratio of intake to exhaust side flow rates could be easily controlled while maintaining the flow rates per cylinder of the original model. Flow distribution in the coolant passage of the original model was calculated by CFD and the flow rates at the gasket holes were modified based on the calculation results. The calculated flow rated of the modified gasket holes were reasonably close to target values. For more accurate control of the flow rate distribution, a design method with iterative CFD calculations was also suggested. The final size of gasket holes for the target flow rates were obtained just after a few optimization iterations. These methods can be very useful for the optimization of heat transfer characteristics in engine cylinder head and block.

• 대한기관식도과학회지
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• 제19권1호
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• pp.28-30
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• 2013

Foreign bodies in the oral cavity and pharyngolarynx are frequently observed accidental cases in the otolaryngological fields. Most foreign bodies can be recognized and removable with the manipulation of endoscopes and various instruments. However, foreign bodies that penetrate the oral cavity and oropharynx to appear as a tongue mass are rare. Therefore, such cases easily can be misconceived as tongue tumor at first, so it must involve a more thorough search utilizing such aids as computed tomography. Depending on their location and size, their removal may involve surgical intervention. The authors experienced such a rare case of an elderly male patient, presenting as tongue mass. We hereby report this case along with the relevant literature.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2002년도 춘계학술대회 논문집
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• pp.62-68
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• 2002

본 논문은 CATV Head/End에 사용되는 54∼750 MHz용 업 컨버터(Up-Converter)글 개발하였다. 업 컨버터를 구성하는 증폭기, 주파수 혼합기, 전압제어 발진기 등 핵심 회로들을 개별적으로 설계 제작하고, 이들 각 회로를 전체 모듈에 적용하여 기구물 안에 구현할 수 있도록 하여 소형, 경량을 실현하였으며, 고주파 대역에서 적절한 차폐기술을 확보하는데 주안점을 두었다.

• Asian Pacific Journal of Cancer Prevention
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• 제14권6호
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• pp.3535-3539
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• 2013

Head and neck cancer is one of the leading causes of deaths worldwide. Two genes GSTM1 and GSTT1 involved in phase II of carcinogen detoxification have been frequently studied in the literature. Their null genotypes are thought to be associated with increased head and neck cancer risk. However, the published reviews are not up to date and many important papers have been skipped. The current literature review was restricted to the null genotypes of the GSTM1 and GSTT1 genes with special emphasis on the genotypic status. We found that the size of study sample varied greatly and the oral cavity cancer was more influenced by GSTM1 and GSTT1 gene deletions. With respect to ethnicity Asians are more prone to head and neck cancers with these null genotypes as compared to Europeans and Americans. The current review showed significant associations (OR=9.0, 95%CI; 1.4-9.5; OR=3.7, 95%CI; 1.4-9.5) of GSTM1 and GSTT1 null genotypes with head and neck cancers. Review confirms the data of previous reviews that GSTM1 and GSTT1 gene polymorphisms may be risk factors for cancer initiation.

• 대한두경부종양학회지
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• 제6권1호
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• pp.40-45
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• 1990

Thirty five lesions of 35 patients with locally advanced malignant tumors of head and neck were received thermoradiotherapy with ultrasound and/or 915 MHz microwave. Most of all patients were failed with previous conventional therapeutic trial. Hyperthermia had been done immediately after radiotherapy, twice a week, $43^{\circ}C$ for one hour and radiotherapy had been done 5 fractions per week with a fraction size of 2 Gy up to total 30 to 60 Gy. Conclusions are as follows; 1) Total response rate (CR+PR) of thermoradiotherapy with microwave and ultrasound was 80%. 2) Tumor depth, minimum temperature of tumor center, number of heat fraction and irradiation dose were statistically significant factors affecting response. 3) Hyperthermia with microwave and ultrasound can be used efficiently to control locally advanced malignant tumors in head and neck whether previously received near tolerance dose of radiotherapy or not.

• 대한후두음성언어의학회지
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• 제29권1호
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• pp.5-8
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• 2018

Patients who have the head and neck cancer are usually treated by surgery, radiation therapy, chemotherapy, or combinations of them. These treatments can induce variable degree of aspiration with dysphagia. The type and severity of aspiration depends on the size and location of the original tumor, the structures involved, and the treatment modality used for treatment. The management of aspiration after the head and neck cancer's treatment begins with an accurate evaluation for the cause and mechanism of aspiration through modified barium swallow (MBS) and fiberoptic endoscopic examination of swallowing (FEES). Then, the clinician can use postures, maneuvers, and exercises to treat the swallow disorder and to help the patient achieve optimal function. To achieve optimal swallowing without aspiration, multidimensional rehabilitation by various medical personnel is definitely necessary.

• 대한기관식도과학회지
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• 제15권2호
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• pp.71-74
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• 2009

Myxoma is a benign mesenchymal neoplasm that can occur in the head and neck. Laryngeal myxoma is extremely rare and easily confused with a laryngeal polyp. The common clinical presentation is hoarseness, dysphonia, dyspnea and dysphagia depending on their size and location. Treatment for laryngeal myxoma is complete surgical excision with surrounding normal tissue. To our knowledge, 11 laryngeal myxomas have been reported in the English literature, and all patients except only 1 case were male. We report the second female case of myxoma on a vocal cord with a review of literature.

• 드라이브 ㆍ 컨트롤
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• 제12권2호
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• pp.27-33
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• 2015

Excavators are versatile earthmoving equipment that are used in civil engineering, hydraulic engineering, grading and landscaping, pipeline construction and mining. Effective operator training is essential to ensure safe and efficient operating of the machine. The virtual reality excavator based on simulation using conventional large size monitors is limited by the inability to provide a realistic real world training experience. We proposed a flexible observation method with a head tracking system to improve user feeling and sensation when operating a virtual reality excavator. First, an excavation simulator is designed by combining an excavator SimMechanics model and the virtual world. Second, a head mounted display (HMD) device is presented to replace the cumbersome large screens. Moreover, an Inertial Measurement Unit (IMU) sensor is mounted to the HMD for tracking the movement of the operator's head. These signals consequently change the virtual viewpoint of the virtual reality excavator. Simulation results were used to analyze the performance of the proposed system.