109 research outputs found
INVESTIGATION OF TECHNIQUES FOR REDUCING UNINTENTIONAL ELECTROMAGNETIC EMISSIONS FROM ELECTRONIC CIRCUITS AND SYSTEMS
This dissertation describes three independent studies related to techniques for reducing unintentional electromagnetic emissions from electronic circuits and systems. The topics covered are: low-inductance multi-layer ceramic capacitor for high frequency circuit board decoupling, the application of imbalance difference model to various circuit board and cable geometries, and balanced cable interface for reducing common-mode currents from power inverter. The first chapter discusses the importance and the meaning of the connection inductance associated with MLCCs and analyzes the effect of plate orientation in MLCCs. It demonstrates that vertically oriented plates have no more or less inductance than horizontally oriented plates when the overall dimensions of the plate stack are similar. Decoupling capacitance options at the various levels of a high-speed circuit is investigated to determine the range of frequencies that decoupling at each level is likely to be is effective. Innovative low-inductance capacitive-stem capacitor configurations are described and their connection impedance is compared to that of standard surface-mounted capacitors. The second chapter investigates the imbalance difference model that is a method for modeling how differential-mode signal currents are converted to common-mode noise currents. Various cable geometries to determine how well imbalance factor`s values of DM-to-CM conversion compare to full-wave calculations are explored. The imbalance difference model can be applied to cables with more than two conductors are demonstrated. The third chapter investigates the balanced cable interface for reducing common-mode currents from power inverter. The concept of a balancing network to reduce the common-mode currents on power inverter cables above 30 MHz is introduced. An experimental test set-up is used to demonstrate the effect of a balancing network on the common-mode current, differential-mode current and the common-mode rejection ratio on a balanced cable with an imbalanced termination. The balancing network is also evaluated using a 3-phase brushless DC motor driver to verify its effectiveness in a real application
Semiconductor integrated circuit chip, multilayer chip capacitor and semiconductor integrated circuit chip package
Disclosed are a semiconductor integrated circuit chip, a multilayer chip capacitor, and a semiconductor integrated circuit chip package. The semiconductor integrated circuit chip includes a semiconductor integrated circuit chip body, an input/output terminal disposed on the outside of the semiconductor integrated circuit chip body, and a decoupling capacitor disposed at a side face of the semiconductor integrated circuit chip body and electrically connected to the input/output terminal. The semiconductor integrated circuit chip cab be obtained, which can maintain an impedance of a power distribution network below a target impedance in a wide frequency range, particularly at a high frequency, by minimizing an inductance between a decoupling capacitor and a semiconductor integrated circuit chip
Integration between WSNs and Internet based on Address Internetworking for Web Services
There has been an increasing interest in wireless sensor networks as a new technology to realize ubiquitous computing, and demands for internetworking technology between the wireless sensor networks and the Internet which is based on IP address. For this purpose, this paper proposes and implements the internetworking scheme which assigns IP addresses to the sensor nodes and internetworks based on the gateway-based integration for internetworking between the wireless sensor networks and the Internet. That is, the proposed scheme makes the access to the wireless sensor networks be serviced as like the Web service with internetworking Internet IP address and ZigBee address which is allocated to the sensor node in wireless sensor networks. For validating the proposed scheme, we made experiments using Berkeley TinyOS, Mica Motes, dual protocol stack based on ZigBee and IP, and showed the service result using browser (IE) and IPv6 address based on DNS
Continuous Tip Widening Technique for Roll-to-Roll Fabrication of Dry Adhesives
In this study, we reported continuous partial curing and tip-shaped modification methods for continuous production of dry adhesive with microscale mushroom-shaped structures. Typical fabrication methods of dry adhesive with mushroom-shaped structures are less productive due to the failure of large tips on pillar during demolding. To solve this problem, a typical pillar structure was fabricated through partial curing, and tip widening was realized through applying the proper pressure. Polyurethane acrylate was used in making the mushroom structure using two-step UV-assisted capillary force lithography (CFL). To make the mushroom structure, partial curing was performed on the micropillar, followed by tip widening. Dry adhesives with properties similar to those of typical mushroom-shaped dry adhesives were fabricated with reasonable adhesion force using the two-step UV-assisted CFL. This production technology was applied to the roll-to-roll process to improve productivity, thereby realizing continuous production without any defects. Such a technology is expected to be applied to various fields by achieving the productivity improvement of dry adhesives, which is essential for various applications
Dysphagia in patients with isolated pontine infarction
Little is known about dysphagia after pontine infarction. In this study, we evaluated the incidence of dysphagia after isolated pontine infarction and identified the predictive factors for the occurrence of dysphagia. A total of 146 patients were included in this study. All patients underwent clinical testing for dysphagia within 1 day after admission and at the time of discharge. We compared the incidence of dysphagia between patients with unilateral pontine infarction and those with bilateral pontine infarction. To evaluate the functional status of patients, we investigated their initial modified Rankin Scale (mRS) score and initial National Institutes of Health Stroke Scale (NIHSS) score within 1 day of admission. Of 146 patients, 50 (34.2%) had dysphagia initially within 1 day after admission. At the second evaluation at the time of discharge, dysphagia was diagnosed in 24 patients (16.4%). Patients with bilateral pontine infarction were more likely to present with dysphagia. In addition, clinical severity (in terms of mRS and NIHSS scores) was identified as a predictor of dysphagia in patients with cerebral infarction (multiple binary logistic regression analysis, mRS: P = 0.011, NIHSS: P = 0.004). Dysphagia frequently occurs in patients with isolated pontine infarction. Clinicians should pay particular attention to the occurrence of dysphagia, especially in patients with bilateral pontine infarction or high functional disability
Clinical Outcomes and Prognostic Factors of Up-Front Autologous Stem Cell Transplantation in Patients with Extranodal Natural Killer/T Cell Lymphoma
AbstractLimited data exist on up-front autologous stem cell transplantation (ASCT) in extranodal natural killer/T cell lymphoma (ENKTL). Sixty-two patients (43 men and 19 women) with newly diagnosed ENKTL who underwent up-front ASCT after primary therapy were identified. Poor-risk characteristics included advanced stage (50%), high-intermediate to high-risk International Prognostic Index (25.8%), and group 3 to 4 of NK/T Cell Lymphoma Prognostic Index (NKPI, 67.7%). Pretransplant responses included complete remission in 61.3% and partial remission in 38.7% of patients, and final post-transplantation response included complete remission in 78.3%. Early progression occurred in 12.9%. At a median follow-up of 43.3 months (range, 3.7 to 114.6), 3-year progression-free survival (PFS) was 52.4% and 3-year overall survival (OS) was 60.0%. Patients with limited disease had significantly better 3-year PFS (64.5% versus 40.1%, P = .017) and OS (67.6% versus 52.3%, P = .048) than those with advanced disease. Multivariate analysis showed NKPI and pretransplant response were independent prognostic factors influencing survival, particularly NKPI in limited disease and pretransplant response in advanced disease. Radiotherapy was an independent factor for reduced progression and survival in patients with limited disease, but anthracycline-based chemotherapy was a poor prognostic factor for progression in patients with advanced disease. Up-front ASCT is an active treatment in ENKTL patients responding to primary therapy
Prognostic Factors and Clinical Outcomes of High-Dose Chemotherapy followed by Autologous Stem Cell Transplantation in Patients with Peripheral T Cell Lymphoma, Unspecified: Complete Remission at Transplantation and the Prognostic Index of Peripheral T Cell Lymphoma Are the Major Factors Predictive of Outcome
AbstractHigh-dose chemotherapy followed by autologous stem cell transplantation (HDT/ASCT) offers a rescue option for T cell lymphoma patients with poor prognosis. However, the effectiveness of HDT/ASCT in patients with various peripheral T cell subtypes, optimal transplant timing, and the prognostic factors that predict better outcomes, have not been identified. We retrospectively investigated the clinical outcomes and prognostic factors for HDT/ASCT in 64 Korean patients with peripheral T cell lymphoma, unspecified (PTCL-U) between March 1995 and February 2007. The median age at transplantation was 44 years (range: 15-63 years). According to the age-adjusted International Prognostic Index (a-IPI) and the prognostic index of PTCL (PIT), 8 patients (12.5%) were in the high-risk group and 16 (26.6%) had the 2-3 PIT factors, respectively. After a median follow-up of 29.7 months, the 3-year overall survival (OS) and progression-free survival (PFS) rates were 53.0% ± 7.5% and 44.3% ± 7.0%, respectively. Univariate analysis showed that poor performance status, high lactate dehydrogenase (LDH) levels, high a-IPI score, high PIT classes, failure to achieve complete response (CR) at transplantation, and nonfrontline transplantation were associated with poor OS. Multivariate analysis showed that failure to achieve CR at transplantation (hazard ratio [HR] 2.23; 95% confidence interval [CI] 1.78-7.93) and 2-3 PIT factors (HR 3.76; 95% CI 1.02-5.42) were independent prognostic factors for OS. Failure to achieve CR at transplantation and high PIT are negative predictable factors for survival following HDT/ASCT in patients with PTCL-U
Influence of Nasogastric Tubes on Swallowing in Stroke Patients: Measuring Hyoid Bone Movement With Ultrasonography
Objective To investigate the influence of a nasogastric tube (NGT) on swallowing simulated saliva in stroke patients. Methods Three groups of participants were enrolled into the study: group A (20 stroke patients with a NGT), a control group B (25 stroke patients without a NGT), and group C (25 healthy adults with no brain lesions or dysphagia). Participants swallowed 1 mL of water to simulate saliva. Patients in group A were tested twice: once with a NGT (group A1) and once after the NGT was removed (group A2). The distance of hyoid bone movement was measured by subtracting the shortest distance between the mandible and hyoid bone (S) from the distance at resting state (R) measured with ultrasonography. The degree of the movement was calculated by (R–S)/R. The trajectory area of hyoid bone movement (Area) and the interval between the beginning of hyoid bone movement and the moment of the shortest hyoid−mandible approximation (Interval) was calculated by a computer program. Results From group A: R–S and (R–S)/R of group A2 at 1.14±0.36 cm and 0.30±0.09 cm and were significantly greater than those of group A1 at 0.81±0.36 cm and 0.22±0.08 cm (p=0.009 and p=0.005). After removing the NGT as seen in group A2, R–S and (R–S)/R were improved to the level of those of group B at 1.20±0.32 cm and 0.30±0.09 cm (p=0.909 and p=0.997). The Area of group A2 was larger and the Interval of group A2 was shorter than those of group A1 though a comparison of these factors between A2 and A1 did not show a statistically significant difference. Conclusion A NGT interferes with the movement of the hyoid bone when swallowing 1 mL of water in stroke patients though the movement is restored to normal after removing the NGT
Influence of Donor's Renal Function on the Outcome of Living Kidney Transplantation: 10-Year Follow-up
Purpose: With the improved surgical techniques and immunosuppression available today, conventional prognostic factors have taken on less significance. Accordingly, the native renal function of the donor is thought to be more important. Thus, we analyzed the prognostic significance of the donor’s renal function as assessed by 24-hour urine creatinine clearance on kidney graft survival for 10 years after living kidney transplantation. Materials and Methods: From January 1998 to July 2000, 71 living kidney transplantations were performed at a single institution. From among these, 68 recipients were followed for more than 6 months and were included in the present analysis. We analyzed kidney graft survival according to clinical parameters of the donor and the recipient. Results: Mean follow-up duration of recipients after living kidney transplantation was 115.0±39.4 months (range, 10 to 157 months), and 31 recipients (45.6%) experienced kidney graft loss during this time period. Estimated mean kidney graft survival time was 131.8±6.2 months, and 5-year and 10-year kidney graft survival rates were estimated as 88.2 % and 61.0%, respectively. Donor’s mean 24-hour urine creatinine clearance (Ccr) before kidney transplantation was 122.8±21.2 ml/min/1.73 m 2 (range, 70.1 to 186.6 ml/min/1.73 m 2). The 10-year kidney graft survival rates for cases stratified by a donor’s Ccr lower and higher than 120 ml/min/1.73 m 2 were 39.0 % and 67.2%, respectively (p=0.005). In univariate and multivariate analysis, donor’s Ccr was retained as an independent prognostic factor of kidney graft survival (p=0.001 and 0.005, respectively). Conclusions: Donor’s 24-hour urine Ccr before living kidney transplantation was an independent prognostic factor of kidney graft survival. Therefore, it should be considered before living kidney transplantation
The effect of propofol on emergence agitation in children receiving sevoflurane for adenotonsillectomy
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