A Review: Circuit Theory of Microstrip Antennas for Dual-, Multi-, and Ultra-Widebands

In this chapter, a review has been presented on dual-band, multiband, and ultra-wideband (UWB). This review has been classified according to antenna feeding and loading of antennas using slots and notch and coplanar structure. Thereafter a comparison of dual-band, multiband, and ultra-wideband antenna has been presented. The basic geometry of patch antenna has been present along with its equivalent circuit diagram. It has been observed that patch antenna geometry for ultra-wideband is difficult to achieve with normal structure. Ultra-wideband antennas are achieved with two or more techniques; mostly UWB antennas are achieved from coplaner structures

Framework for ad-hoc invention sharing over a campus network

Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2007.Includes bibliographical references (leaves 57-60).In the future, there will be a large number of devices, and most of us will own more than one (some of us already do). Many individual innovators write programs that exploit features on such devices for interesting, non-standard uses. Usually such inventions are lost over time. In this thesis, we propose a framework called UniPlug that encourages rapid and ad-hoc sharing of such inventions. It works by providing distributed repositories to make inventions publicly available, and providing an easy to use client that locates and fetches inventions for devices that a user owns. We begin by introducing the problem and related work. We then formulate the problem technically and design a solution. This is followed by the description of the implementation of a proof of concept. Further, we discuss its applicability to disseminating inventions for medical devices along with an example scenario. We conclude by summarizing this work, and briefly describing our planned future work.by Durga Prasad Pandey.S.M

Morbidity Pattern and Health Seeking Behavior of Elderly People in Surnaya Rural Municipality, Baitadi, Nepal

Background: The number of older persons in the world has increased substantially in recent years and the growth is projected to accelerate in the coming decades. With an increase in the proportion of aged population, the elderly with ailments is also on the rise. The aged population has special health problems that are different from those of adults or young. This study aims to assess the morbidity patterns and health seeking behavior of elderly people. Methods: A community-based, cross-sectional study was conducted among 197 elderly people in Surnaya Rural Municipality, Baitadi. Data was collected through face-to-face interview using a pre-tested structured questionnaire. Ethical approval was received, and ethical issues were addressed. Data were processed using IBS SPSS v.25.0. Descriptive statistics and chi-square test was used. Results: The prevalence of morbidity was 71.6%. Respiratory condition was most reported, followed by digestive, musculoskeletal, and cardiovascular diseases. Further, 17.0% sustained injury. Healthcare seeking by 77.3% and 76.1% had treatment compliance. The morbidity condition was significantly associated with economic status (p=0.041), spiritual activity (p=0.032), and difficulty falling asleep (p=0.003). Distance to reach the nearest health facility (p=0.022) and presence of chronic health problems (p<0.001) was significantly associated with healthcare seeking behavior of the elderly. Conclusion: The high prevalence of multiple morbidities was reported among the elderly and respiratory condition was leading. Still, large numbers of elderly do not seek healthcare and have low treatment compliance. Elderly-friendly health services, an extension of health insurance, and elderly health screening services are recommended to enhance health seeking behavior of the elderly

NUMERICAL INVESTIGATION OF ON-POWER REFUELING IN A NATURAL CIRCULATION BOILING WATER REACTOR

ABSTRACT Most two-phase heat exchangers consist of multiple parallel boiling channels, and studies concerning multi-channel instabilities in boiling systems are of significant interest. The natural circulation boiling water reactor (NCBWR) considered in the present work is a pressure tube type boiling light water cooled and heavy water moderated reactor. The primary heat transport loop, comprising a number of parallel channels, is modeled by RELAP5/MOD3.4. The effects of on-power refueling on the flow rate and stability of the system are investigated. The conditions under which a sustainable flow rate can be maintained during on-power refueling are explored. It is observed that during on-power refueling, a near-stagnation condition or low-velocity reverse flow can occur, the possibility of reverse flow being higher at low pressures and low powers

Dosimetric Validation of Physical and Biological Indexes from the Dose-Volume Histogram for Evaluation of 3D-CRT and IMRT Techniques with VMAT Treatment Plan Techniques in Cervical Tumors from In-House Developed Software

Introduction:This study aims to investigate the Normal Tissue Complication Probability (NTCP) and Tumor Control Probability (TCP) of cervical cancer from Niemierko radiobiological model and compared with Lyman-Kutcher-Butcher (LKB) model’s effective volume parameter in three different planning techniques such as 3-Dimensional Conformal Radiation Therapy (3D-CRT), Intensity Modulated Radiotherapy (IMRT) and Volumetric Arc Therapy (VMAT).Material and Methods:Twenty patients were selected with Grade II and Grade III and the treatment plan was initially generated for 3D-CRT, IMRT and VMAT. The physical dose from each voxel in radiotherapy treatment planning was extracted through a dose volume histogram (DVH) text file from in-built software developed using python program.  Software was developed by freely available python integration with an integrated Oracle database to store the outcome results with user-friendly graphical user interface for editing the radiological parameter values and viewing the DVH graph. The dosimetricconformalities parameters such as homogeneity index (HI) and conformity index (CI) along with radiobiological parameters such as TCP, NTCP and effective volume (Veff) were compared with three different planning techniques.Results:The IMRT and VMAT dose delivery techniques improve the efficiency of the treatment of cervical cancer with good coverage of target volume as well as low irradiation of Organ at Risk (OARs) compared with 3D-CRT.Conclusion: There is no significant difference in effective volume for IMRT and VMAT, which proportionally increases with the advanced planning techniques, causes insignificant complication probability to normal tissues. Other conformalities parameters were showing good agreement for all the three techniques

Variability of French Bean in the Western Mid Hills of Nepal

ABSTRACT Variability was studied among 18 exotic and indigenous French bean (Phaseolus vulgaris L.) genotypes collected from research centers, agro-vets and traditional farming villages of the western hills of Nepal. The collected genotypes were field evaluated at the Agriculture Research Station, Malepatan, Pokhara at 848 m above sea level during the summer season of 2010 with the objectives to assess the variability in the exotic and indigenous genotypes and their potential for utilization in improvement programs. The results of the study showed that the variability was higher in adaptation, vegetative growth, floral and pod characteristics. The plant survival at harvest was higher in pole-type than in bush-type beans ranging from 97.92 to 54.17% with means of 83.71% and 79.80%, respectively. Bush-type beans were earlier in flowering than pole-type beans ranging from 32 to 174.33 d with a mean of 35.76 and 76.61 d, respectively. Pod length and width were higher in pole-type beans than in bush-type beans ranging from 20.45 to 7.67 cm in length and 33.53 to 7.37 mm in width. The variability indicated that the collected genotypes were distinctly different. The results revealed that the French bean genotype in the mid hills of Nepal is highly diverse and could be considered as the secondary center of genetic diversity. The diverse genotypes should be conserved and utilized for varietal improvement

Parametric effects on reactivity instabilities and nonlinear oscillations in a nuclear-coupled double channel natural circulation boiling system

Natural circulation boiling systems consisting of parallel channels can undergo different types of oscillations (in-phase or out-of-phase) depending on the geometric parameters and operating conditions. The coupling between the neutronics and thermal-hydraulics has a strong influence on the modes of oscillations in a multi-channel system. In the present study a natural circulation double channel system is modeled. The reactor kinetics is represented by multi-point neutron kinetics model which includes the spatial variation of neutrons. Parametric effects on stability of the system, frequency, and the oscillation modes (reactivity instabilities) are investigated. It is found that at high powers compact cores will be more stable compared to larger cores, while the opposite will be the case at low powers. Further, nonlinear analysis is carried out to investigate the parametric effects on the bifurcation characteristics, transition from one mode to the other mode and chaotic oscillations. The delay in heat transfer and strong neutron interactions between the subcores delays the occurrence of chaotic oscillations.by G.V. Durga Prasad and Manmohan Pande

Providing connectivity to the Saami nomadic community

Godkänd; 2002; 20070416 (biem)</p

Diffuse ferroelectric transition and relaxational dipolar freezing in (Ba,Sr)TiO<SUB>3</SUB>: III. Role of order parameter fluctuations

Results of a high-temperature x-ray powder diffraction study of the phase transition between cubic and tetragonal phases of (Ba1-xSrx)TiO3are presented for x = 0.08 and 0.12 which exhibit sharp and diffuse dielectric anomalies, respectively. Experimental evidence and arguments are advanced to show that the cubic and tetragonal phases coexist over a wide range of temperatures and that this coexistence is due to the fluctuation of the order parameter which is coupled electrostrictively to strains. For x = 0.08, the phase coexistence disappears below the dielectric anomaly temperature T'm, indicating the critical nature of the fluctuations. For x = 0.12, these fluctuations are non-critical since the phase coexistence persists even below T'm. The complete conversion to the tetragonal phase occurs at Ts ≈ 75° which is nearly 25° lower than T'm (=102 ± 1° ). It is shown that the spontaneous polarization also increases gradually below T'm and levels off at Tp ≈ 75°. The existence of structural and polarization anomalies well below the frequency-independent dielectric anomaly temperature T'm cannot be rationalized either in terms of the Landau-like theories for ferroelectric transitions which predict Ts=Tp=T'm or in terms of dipole glass transitions and/or relaxor ferroelectric transitions for which T'm should be frequency dependent