• Asian Pacific Journal of Cancer Prevention
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• 제15권15호
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• pp.6155-6160
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• 2014

Background: This study was conducted to investigate whether apparent diffusion coefficient (ADC) measurements by dividing the liver into left and right hepatic lobes may be utilized to improve the accuracy of differential diagnosis of benign and malignant focal liver lesions. Materials and Methods: A total of 269 consecutive patients with 429 focal liver lesions were examined by 3-T magnetic resonance imaging that included diffusion-weighted imaging. For 58 patients with focal liver lesions of the same etiology in left and right hepatic lobes, ADCs of normal liver parenchyma and focal liver lesions were calculated and compared using the paired t-test. For all 269 patients, ADC cutoffs for focal liver lesions and diagnostic accuracy in the left hepatic lobe, right hepatic lobe and whole liver were evaluated by receiver operating characteristic curve analysis. Results: For the group of 58 patients, mean ADCs of normal liver parenchyma and focal liver lesions in the left hepatic lobe were significantly higher than those in the right hepatic lobe. For differentiating malignant lesions from benign lesions in all patients, the sensitivity and specificity were 92.6% and 92.0% in the left hepatic lobe, 94.4% and 94.4% in the right hepatic lobe, and 90.4% and 94.7% in the whole liver, respectively. The area under the curve of the right hepatic lobe, but not the left hepatic lobe, was higher than that of the whole liver. Conclusions: ADCs of normal liver parenchyma and focal liver lesions in the left hepatic lobe were significantly higher than those in the right hepatic lobe. Optimal ADC cutoff for focal liver lesions in the right hepatic lobe, but not in the left hepatic lobe, had higher diagnostic accuracy compared with that in the whole liver.

• 한국유체기계학회 논문집
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• 제3권2호
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• pp.50-56
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• 2000

The effects of lobe shapes on the leak flow conductance of Roots-type vacuum pump are studied numerically and experimentally. The modelled lobe shape of Roots-type vacuum pump is two-lobe spur gear. The numerical analyses are performed on leak flows in Roots-type vacuum pump. It is numerically calculated using a 4th-order Runge-Kutta method and is compared with experimental results. Results show that for the case of involute lobe shape the total amount of the leak flow conductance is greater than that of cycloid and Cassini oval lobe shapes.

• Journal of electromagnetic engineering and science
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• 제3권1호
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• pp.17-21
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• 2003

In this paper, we design an optimal planar array geometry for maximum side-lobe reduction. The concept of thinned array is applied to obtain an optimal two dimensional(2-D) planar array structure. First, a 2-D rectangular array with uniform spacing is used as an initial planar array structure. Next, we modify the initial planar array geometry with the aid of thinned array theory in order to reduce the maximum side-lobe level. This is implemented by a genetic algorithm under some constraint, minimizing the maximum side-lobe level of the 2-D planar array. It is shown that the optimized planar array structure can achieve low side-lobe level without optimizing the excitations of the array antennas.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.813-818
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• 2000

The objective of this study is to elucidate the characteristic performance of Roots-type vacuum pump with Cassini oval lobe shape. The modelled lobe shape of Roots-type vacuum pump is two-lobe spur gear. The numerical analyses are performed fer leak flows, using 4th-order Runge-Kutta method and are compared with experimental results. Results show that for the case of involute lobe shape the total amount of the leak flow conductance is greater than that of cycloid and Cassini oval lobe shapes.

• Journal of Advanced Marine Engineering and Technology
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• 제31권5호
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• pp.522-530
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• 2007

In order to extract small hydropower in the very low specific speed range of $n_s<10$, a Positive Displacement Turbine (PDT) has been proposed and steady performances have been determined experimentally. However, the suppression of large pressure fluctuation is inevitable for practical application of PDT. Therefore, present study adopted 4-lobe helical type robe to reduce the pressure fluctuation. The results show that 4-lobe helical type robe can be adopted to suppress the pressure fluctuation drastically. Moreover, efficiency and unit power of the turbine with newly proposed 4-lobe helical type lobe are higher than those of the turbine with 3-lobe straight type robe.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권6호
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• pp.588-591
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• 2010

Parotid deep lobe tumors usually has been treated by total parotidectomy. But there is functional and aesthetic side effects such as post parotidectomy depressions, variable aesthetic deformities, facial nerve injury and Frey's syndrome. Conservative limited deep parotidectomy may result in fewer side effect. Preservation of the superficial lobe for deep lobe tumors could decrease the incidence of complications without any problems in the treatment effect. Additionally, the parotid function preservation and cosmetic appearance after operation also satisfy both the patients and surgeons. We report a case of pleomorphic adenoma of the deep lobe which has been successfully treated by conservative deep parotidectomy.

• Journal of Chest Surgery
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• 제36권2호
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• pp.118-121
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• 2003

25세 여자 환자가 우측 하흉부 및 좌측 상복부의 불쾌감을 주소로 입원하였다. 흉부 X-선 및 흉부 전산화 단층촬영 소견상 우폐 하엽에 위치하며 횡격막과 접하고있는 4$\times$4$\times$4cm 크기의 둥근 종괴가 관찰되고, 우폐하엽과 우폐 중엽에서 전이성 병변들이 관찰되었나. 시험적 개흉술 결과 우측 횡격막에서 기시한 종괴가 우폐 하엽에 직접 침범되어있었으며. 우폐 하엽과 우폐 중엽의 흉막하에 전이성 병변들이 발견되었다. 종괴에 대한 냉동 절편 조직 검사상 육종으로 진단되어 종괴 기시부의 횡격막 및 종괴에 의해 침범된 부위의 우폐 하엽을 일괄 절제하고 우폐 하엽과 우폐 중엽의 전이성 병변들을 쐐기 절제하였다. 최종 조직 검사상 횡격막의 악성 섬유성 조직구종이었고, 보조적 항암 약물 치료를 추가로 시행하였다. 저자들은 횡경막에서의 발생이 극히 드문 악성 섬유성 조직구종 1례를 문헌고찰과 함께 보고하는 바이다.

• 한국정밀공학회지
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• 제26권3호
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• pp.103-112
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• 2009

A internal lobe pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. In particular, the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobe with elliptical and involute shapes, while the inner rotor profile is determined as conjugate to the other. And the integrated system which is composed of three main modules has been developed through AutoLISP under AutoCAD circumstance. It generates new lobe profile and calculates automatically the flow rate and flow rate irregularity according to the lobe profile generated. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field.

• 한국정밀공학회지
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• 제26권1호
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• pp.120-129
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• 2009

An internal lobe pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. In particular, the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobes with elliptical shape, while the inner rotor profile is determined as conjugate to the other. And the integrated system which is composed of three main modules has been developed through AutoLISP under AutoCAD circumstance. It generates new lobe profile and calculates automatically the flow rate and flow rate irregularity according to the lobe profile generated. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field.

• 생물정신의학
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• 제9권2호
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• pp.95-102
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• 2002

Objectives:Abnormalities in the frontal lobe have been consistently suggested in the pathophysiology of depression. The purpose of this review is to discuss the relationship between the frontal lobe and depression. Methods:Recent researches on the frontal lobe in depression were reviewed and abnormalities in this region were considered within the context of modern functional neuroanatomy. Results:This paper reviewed evidence strongly implicating the frontal lobe as a key brain structure in depression. Conclusion:Taken together, these abnormalities in the function of the frontal lobe implicate interconnected neural circuits in depression and offer suggestions for the themes of future research and treatment. Further research is needed to investigate the association between emotion and the brain in the paradigm of "affective neuroscience".