• Journal of Korean Neurosurgical Society
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• v.30 no.3
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• pp.371-375
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• 2001

Intracranial hemorrhage due to preeclampsia in the postpartum woman is rarely documented. Generally, the incidence of stroke is increased during pregnancy and early postpartum. Preeclampsia is considered a main cause of both nonhemorrhagic and hemorrhagic stroke. We present a 32-year-old woman who had intracranial hemorrhage at 5 days postpartum. At admission, her consciousness was semicomatose with elevated blood pressure. Computerized tomography revealed intracranial hemorrhage on right frontal lobe. Additional angiography did not reveal abnormal vascular lesion. Emergency craniectomy with hematoma removal was done. However, the patient showed no recovery and died 2 weeks later. We conclude that postpartum care of preeclampsia is important to prevent intraparenchymal hemorrhage. Relative high risk of stroke during the postpartum period suggests a causal roles for the large decrease in blood volume or the rapid changes in hormonal status that follow a live birth or stillbirth, perhaps by means of hemodynamics, coagulative, or vessel wall changes.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.6
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• pp.228-236
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• 2014

Towed array SONAR is deformed because it operates in fluid such as an ocean. It especially undergoes significant change in shape as a towing vessel takes a turn. In this case, beam pattern synthesis of the line array is limited, resulting in degradation in quality such as signal-to-noise ratio. This paper presents a modified two-step least squares algorithm based on the two-step least squares method. The shape of the sea-operated line array formation with the towing vessel changing course(angle) was modeled and the algorithm was subsequently applied. While changing course and location of the main lobe in beam pattern was altered, signal-to-noise ratio of steering beam pattern synthesis was analyzed by algorithm (proposed and others). As a result, the proposed algorithm presented improvement in performance by 2dB compared to other algorithms while forming relatively constant beam pattern.

• Tuberculosis and Respiratory Diseases
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• v.40 no.1
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• pp.58-66
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• 1993

Mucoepidermoid carcinoma of the lung can be divided into low grade and high grade varieties, like their major salivary glands counterparts. This carcinoma comprises only. about 0.5% of all pulmonary neoplasma. Their clinical and biologic behaviors are closely related with histologic grade of carcinoma. We have experienced two cases of mucoepidermoid carcinoma. Case 1 occurred in a 16 years old male and showed the histologic features of low grade type. This carcinoma arised from the right upper lobe bronchus which was removed by the right upper lobectomy. Case 2 occurred in a 41 year old male was the high grade carcinoma located at the distal left main bronchus which was removed by the left pnemonectomy.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.177-184
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• 2018

In this paper, we analyze the characteristics of the antenna by changing the structure of the radiator and the angle of the branch of the array patch antenna. First, the structure of the radiator was changed from the rectangular patch to a hexagonal patch, a triangular patch. Secondly, we changed the angle of the feeder branch to $5^{\circ}$, $10^{\circ}$, $15^{\circ}$, $20^{\circ}$. When the branch angle is $10^{\circ}$, the measured 10dB frequency band is 23.38 GHz-24.19GHz and the bandwidth is 810MHz. The fabricated antenna has a gain of 9.65-10.06dBi at 24.05 GHz. The beam width of the main lobe is $12^{\circ}$, and the antenna size is $70{\times}36mm^2$. In addition to the rectangular patch, it is possible to maintain the performance by using patches of other shapes, and it is confirmed that by changing the feeder branch at various angles, it is possible to reduce the substrate size and contribute to diversity in the fabrication of the array antenna.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1493-1510
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• 2000

Theoretical models that can be used to predict the range of main lobe widths and the probability distribution of the peak sidelobe levels of two-dimensionally sparse arrays are presented here. The arrays are considered to comprise microphones that are randomly positioned on a segmented grid of a given size. First, approximate expressions for the expected squared magnitude of the aperture smoothing function and the variance of the squared magnitude of the aperture smoothing function about this mean are formulated for the random arrays considered in the present study. By using the variance function, the mean value and the lower end of the range i.e., the first I percent of the mainlobe distribution can be predicted with reasonable accuracy. To predict the probability distribution of the peak sidelobe levels, distributions of levels are modeled by a Weibull distribution at each peak in the sidelobe region of the expected squared magnitude of the aperture smoothing function. The two parameters of the Weibull distribution are estimated from the means and variances of the levels at the corresponding locations. Next, the probability distribution of the peak sidelobe levels are assumed to be determined by a procedure in which the peak sidelobe level is determined as the maximum among a finite number of independent random sidelobe levels. It is found that the model obtained from the above approach predicts the probability density function of the peak sidelobe level distribution reasonably well for the various combinations of two different numbers of microphones and grid sizes tested in the present study. The application of these models to the design of random, sparse arrays having specified performance levels is also discussed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.6
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• pp.515-521
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• 2014

In this paper, we designed axis-displaced Gregorian antenna by using Ray-tracing method. This antenna improves gain, VSWR by rotating the axis of the sub-reflector to get rid of E-field wave returned from sub-reflector to feed horn. Therefore it reduce the sub-reflector size and the volume of antenna. This method is used to track the propagation path for radiation pattern of feed horn from feed horn to sub-reflector, main-reflector and air. We get E-field distribution of this antenna aperture and calculate antenna radiation pattern and optimize the antenna performance. The Ray-tracing Method was verified because the gain, radiation patterns, side lobe level, beam width and return loss of the designed antenna are very similar to CST simulation result and a measured result of the fabricated antenna.

• Journal of Chest Surgery
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• v.25 no.1
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• pp.79-85
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• 1992

We have analyzed 1559 operated cases during the 32 year period, from October, 1958 to December, 1990. Annual incidence of the surgical treatment decreased from 101[1960] to 25[1990]. The ratio between male and female was 2.1: 1 and the age of peak incidence was in the 3rd and 4th decades. Recently, patients below the age of 20 years were decreased, but above 50 years were much increased. The patients were consisted of far-advanced case in 71.8% and moderately-advanced case in 22.0% in 1990, as compared with 44% and 54% correspondingly in 1960. Preoperative sputum positivity decreased from 91%[1958~1963] to 38%[1982~1990]. Preoperative antituberculous chemotherapy for more than 3 years increased from 16% [1958~1963] to 56.5% [1982~1990]. From the view of surgical indication, totally destroyed lung and destroyed lobe or segment has been main indication. Recently empyema with parenchymal lesion was increased, and so more extensive surgical resection such as pleuropneumonectomy was performed more frequently. The trends in the mode of surgical treatment revealed that thoracoplasty has virtually disappeared and operations required for residuals of pleural disease have increased. Postoperative mortality increased from 1.6-2.0% to 3.6% recently as well as morbidity. On the basis of our study, far-advanced and drug-resistant patients increased in number recently, whose pulmonary function was poor. So postoperative mortality and morbidity was increased despite improved anesthetic and surgical techniques. Proper surgical intervention should be considered before the appearance of resistance for all chemotherapeutic drugs.

• Journal of Chest Surgery
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• v.32 no.1
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• pp.62-65
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• 1999

Infantile lobar emphysema is an uncommon disease affecting newborns and infants with varying degree of respiratory distress, lobar overaeration, mediastinal shift and herniation. Although the etiology of the condition is most commonly idiopathic, there is a clear association with congenital heart disease, particularly in the presence of pulmonary hypertension due to left to right shunt. Sites of predilection are the left main bronchus, the left upper and right middle bronchi. This report describes a two-week-old boy who had right middle lobe emphysema with large ventricular septal defect. At first, patch closure of perimembranous ventricular septal defect was performed. Postoperatively, the patient required continuing assisted ventilation and the lobar emphysema was not improve. One week following the initial operation, right middle lobectomy was successfully performed and the patient was weaned from artificial ventilator on the 5th postoperative day. The patient was discharged with good general condition on the 45th postoperative day.

• Tuberculosis and Respiratory Diseases
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• v.46 no.3
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• pp.432-437
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• 1999

Benign fibrous mesothelioma of the pleura is a relatively rare neoplasm originated from pleural mesothelial cell, often asymptomatic or presenting with a specifical sign. One of the main problems, concerns the preoperative differential diagnosis, mainly because it is difficult to differentiate between benign and malignant type. A 62-year old woman presented with recurrent chest pain. The chest radiography in a patient was suspected localized pleural mesothelioma. The chest computed tomography scan showed that mass like lesion of well marginated ovoid shape with homogenous attenuation on anterior-basal segment of right lower lobe. After resection of a pleural mass by thoracoscopic extirpation from right hemithorax, Localized benign fibrous mesothelioma of the pleura was confirmed by pathology and immunohisto-chemical staining. We report here one case of pleural benign fibrous mesothelioma with some considerations on its diagnosis and treatment.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.201-204
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• 2015

The common-envelope process is a complicated phase in binary evolution. A lot of effort has been dedicated to study the common-envelope stage, but many questions related to this process are yet to be answered. If one member of the binary survives the common-envelope phase, the binary will emerge as a white dwarf accompanied by a low-mass main sequence star in close orbit, often referred as a post common-envelope binary (PCEB). SDSS J0745+2631 is among the list of newly found PCEBs from the Sloan Digital Sky Survey (SDSS). This star is proposed to be a strong eclipsing system candidate due to the ellipsoidal modulation in its light curve. In this work, we aim to confirm the eclipsing nature of SDSS J0745+2631 and to determine the stellar and orbital parameters using the software Binary Maker 3.0 (BM3.0). We detected the primary eclipse in the light curve of SDSS J0745+2631 in our follow-up observation from January 2014 using the ULTRASPEC instrument at the Thai National Observatory. The data obtained on 7th and 8th January 2014 in g filter show an evident drop in brightness during the eclipse of the white dwarf, but this eclipse is less prominent in the data taken on the next night using a clear filter. According to our preliminary model, we find that SDSS J0745+2631 hosts a rather hot white dwarf with an effective temperature of 11500K. The companion star is a red dwarf star with a temperature of 3800K and radius of 0.3100 $R_{\odot}$. The red dwarf star almost fills its Roche lobe, causing a large ellipsoidal modulation. The mass ratio of the binary given by the Binary Maker 3.0 (BM3.0) model is M2/M1 = 0.33.