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[en] This book is divided into four parts, which deals with process control on Mat lab. The first part mentions introduction on process control, process control function, system, summery, check questions and practice questions, laplace and linearization and chemical process modeling. The second part has dynamic property using Mat lab and check questions. The third part deals with feedback control structure on element of structure, stability and dynamic property using Mat lab. The standard explains libration response with analysis, standard of stability on bode and Nyquist, use of Mat lab, questions for check and practice.
[en] This book is about chemical process control, which includes the basis of process control with conception, function, composition of system and summary, change of laplace and linearization, modeling of chemical process, transfer function and block diagram, the first dynamic property of process, the second dynamic property of process, the dynamic property of combined process, control structure of feedback on component of control system, the dynamic property of feedback control loop, stability of closed loop control structure, expression of process, modification and composition of controller, analysis of vibration response and adjustment controller using vibration response.
[en] An experimental study has been conducted to measure the temperature fields for two and three staggered rows of the rectangular shaped-holes with high turbulence intensity. 10% turbulence intensity is obtained by installation of two kinds of grids which have different shapes. One grid which is installed at 30d upstream from center of 1st row of holes is composed of vertical cylinders of which diameter is 10mm and center to center distance is 18mm. The other installed 15d apart to upstream from center of 1st row of holes which has square pattern is constructed of 3mm square bars and bar spacing is 25mm. Temperature fields are measured by using a thermocouple rake which is attached on three-axis traversing system. The results show that the overall values are decreased and the thicker film of coolant is formed downstream of rows of holes for high mainstream turbulence intensity
[en] To evaluate the patterns of pseudo-lesions present on spiral CT hepatic arteriography (CTHA). One hundred and seventy five patients (161 men and 14 women, aged 15-70 years [mean, 52 years]) who underwent spiral CTHA for the detection of hepatic lesions were retrospectively reviewed. Pseudo-lesion type was determined by comparing hyperattenuating lesions on CTHA with the findings of ultrasonography, conventional or multi-phase CT, Lipiodol CT, angiography, CT arterial portography(CTAP), and follow-up of spiral CTHA. Pseudo-lesions were classified according to site, size and shape. A total of 77 pseudo-lesions were found in 56 of the 175 patients(32.6%), and were classified into the following types : peritumoral(n=18), segment I(n=3), segment IV(n=3), gallbladder fossa (n=13), subsegmental (n=3), subcapsular (n=13), straight line sign (n=10), arterioportal shunt (n=13), and technical error (n=1). Fifteen of 77 pseudo-lesions(19.5%) showed hyperattenuation on CTHA and isoattenuation on CTAP, in contrast to adjacent liver parenchyma. In patients with hepatic mass, it is very important to understand the characteristic site, shape and size of pseudo-lesions for the correct interpretation of CT and subsequent management of the patient
[en] Sn-doped In_2O_3 (Indium tin oxide, ITO) is widely utilized in numerous industrial applications due to its high electrical conductivity and high optical transmittance in the visible region. High quality ITO thin-films have been grown at room temperature by oxygen radical assisted e-beam evaporation without any post annealing or plasma treatment. The introduction of oxygen radicals during e-beam growth greatly improved the surface morphology and structural properties of the ITO films. The obtained ITO film exhibits higher carrier mobility of 43.2 cm"2/V·s and larger optical transmittance of 84.6%, resulting in a higher figure of merit of ∼ 2.8 × 10"−"2 Ω"−"1, which are quite comparable to the ITO film deposited by conventional e-beam evaporation. These results show that ITO films grown by oxygen radical assisted e-beam evaporation at room temperature with high optical transmittance and high electron conductivity have a great potential for organic optoelectronic devices.
[en] Percutaneous biopsy of bone lesion is usually performed under the guide of fluoroscopy or CT. However ultrasound (US) guided biopsy of bone lesion has seldom reported. We studied the usefulness of US guided biopsy of various bone lesions. We performed the US guided biopsy of various bone lesions in 14 patients (13 male, 1female). Biopsy site was in rib in 2, clavicle in 3, humerus in 3, ileum in 3 and femur in 3 patients. Before the biopsy, we examined the bone lesion with US and anesthesized the overlying skin and the soft tissue. When thedestructed cortex and soft tissue lesion was found, we performed US guided aspiration or tissue biopsy with 21Gspinal needle or the Tru-cut needle. When the cortical defect or soft tissue lesion could not be found, biopsy was done with 15G Ostycut needle. In 13 (93%) of total 14 cases, we could obtain sufficient aspirate or tissue for the pathologic examination. During our early experience, we failed to obtain adequate tissue in one case with plasmacytoma. The biopsy material was proved as pyogenic bone abscess in 1, tuberculous osteomyelitis in 2,primary bone tumor in 3 and metastatic bone tumor in 7. In conclusion, US guided biopsy of bone lesion is safe,useful, and accurate method in the preoperative tissue diagnosis and staging of metastatic bone tumor, primary bone tumor and infectious bone disease. It is particularly valuable as it is performed without radiation
[en] ZnO thin films with thickness of 150 nm were grown on ITO/glass (ITO-coated glass) substrates by using the radio-frequency (RF) sputtering technique at 400 ◦C in an Ar atmosphere. An excimer laser irradiation (ELI) treatment was performed on the surface of ZnO thin films at different excimer laser energy densities of 150, 200, and 250 mJ/cm2 in a N2 atmosphere. The ELI treatment promoted the lateral recystallization of the surface area of the ZnO, resulting in a significant improvement of the crystallinity of the ZnO thin films without substrate damage. As-grown ZnO and ELI-treated ZnO thin films were characterized by using scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). The analyses showed that the ZnO thin film treated with ELI at an excimer laser energy density of 150 mJ/cm2 exhibited the best structural properties.
[en] Hepatic atrophy has been recognized as a complication of hepatic and biliary disease but we have often found it in follow up CT after transcatheter arterial embolization (TACE). The purpose of this study is to evaluate the characteristics of hepatic atrophy after TACE. Of 53 patients who had TACE. We evaluated the relationship between the incidence of hepatic atrophy and the number of TACE, and also evaluated the average number of TACE in patients with hepatic atrophy. Of 20 patients who had received more than average number of TACE for development of hepatic atrophy (2 times with portal vein obstruction, 2.7 times without portal vein obstruction in this study), we evaluated the relationship between the lipiodol uptake pattern of tumor and the incidence of hepatic atrophy. There were 8 cases of hepatic atrophy (3 with portal vein obstruction, 5 without portal vein obstruction), average number for development of hepatic atrophy were 2.5 times. As the number of TACE were increased, the incidence of hepatic atrophy were also increased. Of 20 patients who received more than average number of TACE for development of hepatic atrophy, we noted 6 cases of hepatic atrophy in 11 patients with dense homogenous lipiodol uptake pattern of tumor and noted only 1 case of hepatic atrophy in 9 patient with inhomogenous lipiodol uptake pattern. Hepatic atrophy was one of the CT findings after TACE even without portal vein obstruction. Average number of TACE was 2.5 times and risk factors for development of hepatic atrophy were portal vein obstruction, increased number of TACE, and dense homogenous lipiodol uptake pattern of tumor
[en] The purpose of this study is to evaluate the findings of magnetic resonance imaging (MRI) of posterior fossa hemanangioblastoma and usefulness of contrast enhancement with Gd-DTPA. Seven patients with posterior fossa hemangioblastoma were studied with both pre- and post-enhanced MRI. The MR images were reviewed regarding the location, size, signal intensities of cysts and mural nodules, and their contrast enhancement pattern. Five tumors were located in cerebellar hemisphere, one in vermis, and one in posterior part of medulla. One patient with von Hippel-Lindau disease had a medullary hemangioblastoma with multiple pancreatic cysts. In 6 cases, the major portion of the tumor was cysts and had small mulkal nodules. The solid portion was relatively lange in one cases, cemprising half of the tumor cysts were oval shaped and their sized were 3-6.7 cm in diameter. In five cases(71%), septations were noted within the cysts. Cysts were isointense or slightly hyperintense on T1-weighted image and hyperintense on T2- weighted image compared with cerebrospinal fluid. Mural nodules were oval or rounded radiotherapy had better prognosis than those treated with radiotherapy alwas 0.5-2.5 cm in diameter. Mural nodules were isointense to gray matter. They were detected in five cases on T1-weighted images and one case on T2-weighted images. In two cases, vascular signal void area was noted in mural nodules. On contrast-enhanced T1-weighted images, all mural nodules were intensely enhanced. MRI provide to be a good diagnostic method to detect and characterize posterior fossa hemangioblastoma. The most common finding is Cystic posterior fossa lesion with enhancing mural nodule. Contrast enhancement is essential for specific diagnosis
[en] This study was performed to evaluate the disease-free survival and risk factors of recurrence in early breast cancer patients who have undergone breast conserving surgery and radiation therapy. Materials and Methods: From March 1997 to December 2002, 77 breast cancer patients who underwent breast conserving surgery and radiation therapy were reviewed retrospectively. The median follow-up time was 58.4 months (range 43.8-129.4 months) and the mean subject age was 41 years. The frequency distribution of the different T stages, based on the tumor characteristics was 38 (49.3%) for T1, 28 (36.3%) for T2, 3 for T3, 7 for Tis and 1 for an unidentified sized tumor. In addition, 52 patients (67.5%) did not have axillary lymph metastasis, whereas 14 patients (18.1%) had 1-3 lymph node metastases and 3 (0.03%) had more than 4 lymph node metastases. The resection margin was negative in 59 patients, close (≤2 mm) in 15, and positive in 4. All patients received radiation therapy at the intact breast using tangential fields with a subsequent electron beam boost to the tumor bed at a total dose ranging from 59.4 Gy to 66.4 Gy. Patients with more than four positive axillary lymph nodes received radiation therapy (41.4-60.4 Gy) at the axillary and supraclavicular area. Chemotherapy was administered in 59 patients and tamoxifen or fareston was administered in 29 patients. Results: The 5 year overall survival and disease-free survival rates were 98.08% and 93.49%, respectively. Of the 77 patients, a total of 4 relapses (5.2%), including 1 isolated supraclavicular relapse, 1 supraclavicular relapse with synchronous multiple distant relapses, and 2 distant relapses were observed. No cases of local breast relapses were observed. Lymph node metastasis or number of metastatic lymph nodes was not found to be statistically related with a relapse (p=0.3289) nor disease-free survival (p=0.1430). Patients with positive margins had a significantly shorter disease-free survival period (p<0.0001) and higher relapse rates (p=0.0507). However, patients with close margins were at equal risk of relapse and disease-free survival as with negative margins (p=1.000). Patients younger than 40 years of age had higher relapse rates (9.3% vs. 0%) and lower disease-free survival periods, but the difference was not statistically significant (p=0.1255). The relapse rates for patients with tumors was 14% for tumor stage T2, compared to 0% for tumor stage T1 tumors (p=0.0284). A univariate analysis found that disease-free survival and relapse rates, T stage, positive resection margin and mutation of p53 were significant factors for clinical outcome. Conclusion: The results of this study have shown that breast conservation surgery and radiation therapy in early breast cancer patients has proven to be a safe treatment modality with a low relapse rate and high disease-free survival rate. The patients with a positive margin, T2 stage, and mutation of p53 are associated with statistically higher relapse rates and lower disease-free survival