902 research outputs found
Case Study #6-7 of the Program: ''Food Policy For Developing Countries: The Role Of Government In The Global Food System''
9 pp.©Cornell University, Ithaca, New York. All rights reserved. This case study may be reproduced for educational purposes without express permission but must include acknowledgment to Cornell University. No commercial use is permitted without permission.Tanzanian agriculture is dominated by small-scale subsistence farming. Like the entire economy, agriculture is in a transition from being a command to a market-based production system. The transition process started in the mid-1980s as part of the economic adjustment and structural reform programs and policies supported by Tanzania's development partners. Despite some impressive macroeconomic achievements resulting from the reform programs, agricultural growth and rural poverty reduction continue to present daunting challenges. Few smallholder producers understand how markets work, and even if they do, they do not have the information they need to participate effectively. In response to these development issues, the government of Tanzania, in consultation with International Fund for Agricultural Development (IFAD), identified the suboptimal structure and functioning of the agricultural marketing system as a key area for attention. Liberalization policy has removed many of the old certainties but has not yet provided adequate basis for an efficiently functioning alternative. To meet this need, an investment program entitled Agricultural Marketing Systems Development was proposed to remove constraints to effective operation of the agricultural marketing system and to help smallholder producers acquire the tools needed to participate on favorable terms in the open market. The program consists of four components: producer empowerment and market linkages, financial market support services, rural marketing infrastructure, and agricultural marketing policy development. The producer empowerment and market linkages component was designed to transform agriculture from a subsistence activity to a profitable enterprise in the mindset of smallholder producers by building the management and marketing capacity of these producers and small-scale traders and processors. About 50 percent of all participating producer groups are now well organized, have adopted collective marketing, and can understand which enterprises are profitable. This shift will lead to the commercialization of agriculture. The financial market support services component was created to improve access to financial services for smallholders and small-scale rural traders and processors, and this goal has been achieved among 20 percent of targeted beneficiaries. The rehabilitation of marketing infrastructure, including markets, warehouses, and rural roads, has been 43 percent achieved. The agricultural marketing policy component was designed to create a conducive policy environment for smallholder farmers to gain access to both domestic and export markets in an organized and sustainable manner, with the help of both financial market support services and infrastructure. Issues that currently impede smallholder farmers' access to markets include a weak legal, regulatory, and institutional framework; poor-quality agricultural products; inadequate entrepreneurial skills; poor facilities for processing agricultural products; poorquality agricultural marketing infrastructure; and poor access to market information and intelligence. The program has come up with some policy options designed to facilitate the strategic marketing of agricultural products and ensure fair returns to all stakeholders based on a competitive, efficient, and equitable marketing system. Policy options include harmonizing legislation and regulations to enhance fair and free marketing of food and cash crops; establishing an institutional framework that will improve performance of the agricultural marketing systems based on needs assessments; creating awareness of quality, standards, grades, and governing regulations among agricultural marketing stakeholders; supporting training in entrepreneurial and marketing skills for agricultural marketing stakeholders; promoting primary agroprocessing and value-addition chains; strengthening links between local and foreign firms; mobilizing adequate resources for investment in agriculture and development of agricultural marketing infrastructure in rural areas; and strengthening the Agricultural Marketing Information Services (AMISs) to enhance timely, demand-driven collection, analysis, storage, and dissemination of marketing information. Through the National Strategy for Growth and Reduction of Poverty, Tanzania aims to reduce poverty by transforming the agriculture-based economy into a market-led, competitive, and semiindustrial economy where smallholder farmers dominate the sector. This approach is strongly supported by Tanzania's development partners, including IFAD and the World Bank. In view of the challenges facing smallholder farmers' agricultural marketing systems, your assignment is to assess the adequacy of the developed policy options in assisting the government of Tanzania to achieve its aim and identify the key policy options for success.Cornell University Division of Nutritional Science
Low-Cost Compact Integrated Rectenna for Implantable Medical Receivers
This work describes a novel fully integrated rectenna circuit using tunnelling-based devices for implanted medical devices. An ASPAT (Asymmetric Spacer Layer Tunnel Diode) was used as the active rectifier due to its high non-linearity and temperature insensitivity features. A miniaturized geometry rectenna ( 1×5 mm 2 ) with improved matching characteristics was demonstrated, by integrating a Cockcroft-Walton rectifier with an L-shaped planar folded antenna structure operating at ISM frequency bands. The circuit performance was experimentally explored at various separation distance between transmitter and receiver units. For a 5cm transmission set-up, the rectenna with a single-stage rectifier delivered 0.8V output at 20dBm transmit power. An extended doubler configuration exhibited enhanced performance when multiple stages are used, is predicted to reach 0.24mW output power at 23dBm transmit power and yielding ~1.6V output voltage with an efficiency of 0.12%. These findings can assist in compensating for the degraded antenna gain attributed to the extremely small effective-radiating area of 0.04λ . Furthermore, the ability of controlling the antenna input impedance helps in circumventing the requirement for a matching circuitry thereby offering further reduction in chip size.UWIPOM2 project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 857654
Satisfiability of Circuits and Equations over Finite Malcev Algebras
We show that the satisfiability of circuits over finite Malcev algebra A is NP-complete or A is nilpotent. This strengthens the result from our earlier paper [Idziak and Krzaczkowski, 2018] where nilpotency has been enforced, however with the use of a stronger assumption that no homomorphic image of A has NP-complete circuits satisfiability. Our methods are moreover strong enough to extend our result of [Idziak et al., 2021] from groups to Malcev algebras. Namely we show that tractability of checking if an equation over such an algebra A has a solution enforces its nice structure: A must have a nilpotent congruence ? such that also the quotient algebra A/? is nilpotent. Otherwise, if A has no such congruence ? then the Exponential Time Hypothesis yields a quasipolynomial lower bound. Both our results contain important steps towards a full characterization of finite algebras with tractable circuit satisfiability as well as equation satisfiability
Effect of short-term school closures on the H1N1 pandemic in Japan: a comparative case study
Purpose The 2009 worldwide influenza A/H1N1 pandemic particularly affected younger people, including schoolchildren. We assessed the effects of class/school closure during the pandemic on the spread of H1N1 infection in Japan. Methods We prospectively monitored 2,141 schoolchildren in 57 classes at two elementary schools and two junior high schools in Japan, and evaluated the effects of class/school closures on the spread of H1N1 using descriptive epidemiological methods. Results The cumulative rate of H1N1 infection among these children was 40.9 % (876 children). There was a total of 53 closures of 40 classes, including school closures, during the pandemic. Time-course changes in the epidemic curve showed that school closure reduced the following epidemic peak more than class closure. A Poisson regression model showed that a longer duration of closure was significantly related to decreased H1N1 occurrence after the resumption of classes. Conclusions School closure more effectively inhibits subsequent epidemic outbreaks than class closure. Longer school closures are effective in reducing the spread of infection, and school closure should be implemented as early as possible.ArticleINFECTION. 40(5):549-556 (2012)journal articl
65/Detektory MOSFET jako narzędzie do weryfikowania dawek terapeutycznych wiązek elektronów w radioterapii
CelZastosowanie detektorów MOSFET (Metal – Oxide Semiconductor Field Effect Transistor) do pomiaru dawki in vivo wiązek elektronów w radioterapii.Metody i materiałyWykonano pomiary fantomowe polegające na zbadaniu zależności wskazań detektorów MOSFET od: – wartości dawki wiązek elektronów, – temperatury otoczenia detektorów, – kierunku padania wiązki elektronów na detektor, – wielkości napromienianego pola.Zbadano także zmianę czułości detektorów w zależności od skumulowanej dawki. Detektory, ze względu na bardzo małe wymiary, umieszczano w odpowiednio zaprojektowanych nakładkach aluminiowych – w celu zapewnienia równowagi elektronowej podczas pomiaru dawki. Wskazania detektorów porównywano do wskazańkomory jonizacyjnej typu Markus, posiadającej świadectwowzorcowania. Pomiary wykonano z użyciem wiązek elektronów o energii 6, 9, 12, 15, 18,21 MeV.WynikiZbadane zależności i określone na ich podstawie współczynniki korekcyjne umożliwiają zmierzyć dawkę wiązki elektronów z dokładnością ±2.5%.WniosekDetektory MOSFET są dobrym narzędziemdo weryfikowania dawki wejściowej w radioterapii wiązkami elektronów
Global CO2 Distributions over Land from the Greenhouse Gases Observing Satellite (GOSAT)
January 2009 saw the successful launch of the first space-based mission specifically designed for measuring greenhouse gases, the Japanese Greenhouse gases Observing SATellite (GOSAT). We present global land maps (Level 3 data) of column-averaged CO2 concentrations (X(sub CO2)) derived using observations from the GOSAT ACOS retrieval algorithm, for July through December 2009. The applied geostatistical mapping approach makes it possible to generate maps at high spatial and temporal resolutions that include uncertainty measures and that are derived directly from the Level 2 observations, without invoking an atmospheric transport model or estimates of CO2 uptake and emissions. As such, they are particularly well suited for comparison studies. Results show that the Level 3 maps for July to December 2009 on a lO x 1.250 grid, at six-day resolution capture much of the synoptic scale and regional variability of X(sub CO2), in addition to its overall seasonality. The uncertainty estimates, which reflect local data coverage, X(sub CO2) variability, and retrieval errors, indicate that the Southern latitudes are relatively well-constrained, while the Sahara Desert and the high Northern latitudes are weakly-constrained. A probabilistic comparison to the PCTM/GEOS-5/CASA-GFED model reveals that the most statistically significant discrepancies occur in South America in July and August, and central Asia in September to December. While still preliminary, these results illustrate the usefulness of a high spatiotemporal resolution, data-driven Level 3 data product for direct interpretation and comparison of satellite observations of highly dynamic parameters such as atmospheric CO2
Miniaturized Folded Antenna with Improved Matching Characteristic for mm-wave Detections
UCMMT 2021 - UK-Europe-China Work. Millimetre-Waves Terahertz Technol., Sep. 2021UWIPOM2 project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 857654
Penentuan Sifat Mekanis dan Fisis Batu Bata dengan Penambahan Arang Tempurung Kelapa Asal Alor
Telah dilakukan penelitian tentang penentuan sifat mekanis dan fisis batu bata dengan penambahan tempurung kelapa asal alor. Penenlitian ini bertujuan mengetahui kualitas batu bata yang memenuhi standar kelayakan sebagai bahan konstruksi dengan penambahan arang tempurung kelapa aal alor dengan presentasi 0%, 5%, 10%, 15% terhadap tanah liat (lempung). Batu bata dicetak dengan prosedur pemadatan, pengringn dan pembakaran. Setelah prosedur pencetakkan selesai kemudian di lanjutkan dengan pengujian sefat mekanis dan sifat fisis, yaitu uji kuat tekan (compression strength), densitas (density), porositas (porosity) hasil kuat tekan batu bata didapatkan berdasarkan pengujian: a) uji kuat tekan, batu bata tanpa penambahan (0%) : 4,94 meemenuhi standar kuat tekan kelas 50 (SNI 15-2094-2000), b) uji porositas, batu bata 0% dan 5% : 3,82% dan 17,93% memenuhi standar porositas dengan batas maksimum 20% (SNI 15-2094-2000) dan uji densitas, batu bata tidak ada yang memenuhi standar (SII 0021-1978)
Kata kunci: sifat mekanis, sifat fisis, tempurung kelapa, densitas, porositas, kuat teka
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