469 research outputs found
CLIC RF High Power Production Testing Program
The CLIC Power Extraction and Transfer Structure (PETS) is a passive microwave device in which bunches of the drive beam interact with the impedance of the periodically loaded waveguide and generate RF power for the main linac accelerating structure. The demands on the high power production (~ 150 MW) and the needs to transport the 100 A drive beam for about 1 km without losses, makes the PETS design rather unique and the operation very challenging. In the coming year, an intense PETS testing program will be implemented. The target is to demonstrate the full performance of the PETS operation. The testing program overview and test results available to date are presented
A Multi-Moded RF Delay Line Distribution System for the Next Linear Collider
The Delay Line Distribution System (DLDS) is an alternative to conventional
pulse compression, which enhances the peak power of rf sources while matching
the long pulse of those sources to the shorter filling time of accelerator
structures. We present an implementation of this scheme that combines pairs of
parallel delay lines of the system into single lines. The power of several
sources is combined into a single waveguide delay line using a multi-mode
launcher. The output mode of the launcher is determined by the phase coding of
the input signals. The combined power is extracted from the delay line using
mode-selective extractors, each of which extracts a single mode. Hence, the
phase coding of the sources controls the output port of the combined power. The
power is then fed to the local accelerator structures. We present a detailed
design of such a system, including several implementation methods for the
launchers, extractors, and ancillary high power rf components. The system is
designed so that it can handle the 600 MW peak power required by the NLC design
while maintaining high efficiency.Comment: 25 pages, 11 figure
An Overview of Challenges on Smallholder Agroforestry Farms in Jigawa State, Northern Nigeria
Under the threat from a cocktail of climate change, environmental and soil, degradation and present economic meltdown in the country and world over, the practice of agroforestry come under a myriad of challenges. This study looks at Jigawa state, which has an agrarian based economy. With an estimate of 0.8ha being the average size of farmlands in the state, this study attempts to outline the pressing challenges facing these smallholder farms. A multistage sampling was employed for the study. Using division of the state into 3 zones which include; Jigawa southwest, Jigawa northwest, Jigawa northeast and. Out of each zone, 3LGA were selected out of which 50 respondents were purposively targeted from each community providing the study with sampling frame of 450 respondents. The analysis proceeded by using mean, percentages and use of table and figures. The results show that tenure insecurity, herder problems as challenges to the farmers. Laxity on part of the institutions adds to the list. The study recommends the revitalization of relevant bodies charged with maintenance and dissemination of information and incentives on use of modern agroforestry to ensure its sustainability. Keywords: Agroforestry, Smallholder, Tenure insecurity, Herder Proble
An Assessment of Suitability of Climate for Tourism in Northwestern Nigeria
Tourism is vital to national economies and income of its individual citizens. This paper investigated the suitability of climate for tourism in Northwestern Nigeria using the tourism climate index developed by Mieczkowski (1985). Parameters used for calculating the index include monthly average maximum daily temperature, rainfall, mean daily relative humidity, minimum relative humidity, total wind speed and sunshine hours. The stations used for the calculation of TC index include Kaduna, Kano, Katsina and Sokoto. The result is presented in the form of charts using excel, while GIS is used for zoning of tourism climatic conditions in different months. Result shows that the study area is suitable for tourism throughout the year, as all the TCI scores ranges from 94 to 41 (‘ideal’ to ‘marginal') except for Kano in the month of June which has a TCI score of 39 (‘unfavorable’). The months of January, February, November and December are the best months for tourism as they recorded higher TCI values of 73 to 94 (‘very good’ to ‘ideal’). It is therefore concluded that the best time for tourist to visit Northwestern Nigeria is during the months of January, February, November and December. Keywords: Climate, Tourism, Tourism Climate Index, Nigeri
Recommended from our members
X-Band Traveling Wave Rf Deflector Structures
Design studies on the X-Band transverse RF deflectors operating at HEM{sub ll} mode have been made for two different applications. One is for beam measurement of time-sliced emittance and slice energy spread for the upgraded LCLS project, its optimization in RF efficiency and system design are carefully considered. Another is to design an ultra-fast RF kicker in order to pick up single bunches from the bunch-train of the B-factory storage ring. The challenges are to obtain very short structure filling time with high RF group velocity and good RF efficiency with reasonable transverse shunt impedance. Its RF system will be discussed
Active RF Pulse Compression Using Electrically Controlled Semiconductor Switches
In this paper, we present the recent results of our research on the ultra-high power fast silicon RF switch and its application on active X-Band RF pulse compression systems. This switch is composed of a group of PIN diodes on a high purity silicon wafer and has achieved a switching time of 300ns. The wafer is inserted into a cylindrical waveguide operating in the TE01 mode. Switching is performed by injecting carriers into the bulk silicon through a high current pulse. The RF energy is stored in a room-temperature, high-Q 375 ns delay line; it is then extracted out of the line in a short time using the switch. The pulse compression system has achieved a gain of 8, which is the ratio between output and input power
Recommended from our members
Active RF Pulse Compression using Electrically Controlled Semiconductor Switches
In this paper, we will present our recent results on the research of the ultra-fast high power RF switches based on silicon. We have developed a switch module at X-band which can use a silicon window as the switch. The switching is realized by generation of carriers in the bulk silicon. The carriers can be generated electrically or/and optically. The electrically controlled switches use PIN diodes to inject carrier. We have built the PIN diode switches at X-band, with <300ns switching time. The optically controlled switches use powerful lasers to excite carriers. By combining the laser excitation and electrical carrier generation, significant reduction in the required power of both the laser and the electrical driver is expected. High power test is under going
Knowledge-Based System for the Diagnosis of Flatulence
Diagnosing flatulence involves a thorough assessment of an individual's symptoms, medical history, and, if necessary, the use of diagnostic tests. Healthcare providers gather information about the patient's medical background and conduct a physical examination to identify any signs of gastrointestinal issues. Dietary habits are evaluated, and potential triggers are identified through an elimination diet. Diagnostic tests such as breath tests, stool analysis, or imaging studies may be performed to further investigate the underlying causes of excessive flatulence. Accurate diagnosis is crucial for effective management and treatment of flatulence, enabling individuals to gain control over their symptoms and address any underlying conditions
- …