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Low-Cost Household Groundwater Supply Systems for Developing CommunitiesMaccarthy, Michael 24 June 2014 (has links)
ABSTRACT
Self-supply is widely reported across various contexts, filling gaps left by other forms of water supply provision. This research assesses low-cost household groundwater supply technologies in markets in developing country contexts of sub-Saharan Africa and Latin America, with a focus on the potential for improving Self-supply technology implementation and markets in sub-Saharan Africa. Specifically, a mature and unsubsidized Self-supply market for Pitcher Pump systems (suction pumps fitted onto hand-driven boreholes) is studied in an urban context in Madagascar, EMAS low-cost water supply technologies are assessed in Bolivia, and a technical comparison is completed with manual EMAS Pumps and family versions of the Rope Pump in Uganda.
In Madagascar, locally manufactured Pitcher Pump systems are widely provided by the local private sector, enabling households to access shallow groundwater. This market has developed over several decades, reaching a level of maturity and scale, with 9000 of these systems estimated to be in use in the eastern port city of Tamatave. The market is supplied by more than 50 small businesses that manufacture and install the systems at lower cost (US$35-100) than a connection to the piped water supply system. Mixed methods are used to assess the performance of the Pitcher Pump systems and characteristics of the market. Discussion includes a description of the manufacturing process and sales network that supply Pitcher Pump systems, environmental health concerns related to water quality, pump performance and system management.
The research additionally considers the potential of EMAS low-cost household water supply technologies in accelerating Self-supply in sub-Saharan Africa, and consists of a field assessment of EMAS groundwater supply systems (handpumps on manually-driven boreholes) and rainwater harvesting systems as used at the household level in Bolivia, focusing on user experiences and the medium/long-term sustainability of the pump (cost, functionality, etc.).
The EMAS Pump is a low-cost manual water-lifting device appropriate for use at the household level. Developed in the 1980s, the EMAS Pump has been marketed extensively for local manufacture and use at the household level in Bolivia, and marketed to a lesser extent in other developing countries (mainly in South and Central America). The simple design of the EMAS Pump, using materials commonly found locally in developing countries, allows for it to be fabricated in many rural developing community contexts. Its capability for pumping from significant depths to heights above the pump head makes it quite versatile (e.g. for pumping to household tanks, reservoirs at higher elevations, or for installing multiple pumps on wells). A survey/inspection of 79 EMAS Pumps on household water supply systems in areas of three regions of Bolivia (La Paz, Santa Cruz and Beni regions) showed nearly all EMAS Pumps (78 out of 79) to be operational. 85% of these operational pumps were found to be functioning normally, including 72% that were reported to have been installed eleven or more years earlier. It is shown that rural households in Bolivia are able to maintain EMAS Pumps. The EMAS Pump can be installed and repaired by local technicians, and numerous examples were seen of small groups of local technicians that operate small businesses installing and repairing such systems. The cost of a new EMAS Pump was reported by users to be US$ 30-45. Maintenance and repair costs of the EMAS Pump were found to be reasonable, with pump valve replacement (the repair most commonly reported by users) costing an average of US$9 (materials and labor).
The Rope Pump has some similar attributes to the EMAS Pump, in that it is can be made locally from materials commonly available in developing communities, it has a relatively low cost, and is simple to understand. The Rope Pump is well-known among international rural water supply professionals, and thus serves as a good baseline to compare the lesser-known EMAS Pump. A technical comparison completed in Uganda of the EMAS Pump and the Rope Pump considered performance (flow rates and energy expended, pumping from various depths), material costs, and requirements for local manufacture. The study concluded that, based on its relative low-cost (material costs ranging from 21-60% that of the family Rope Pump, dependent on depth and pumping pipe size), similar technical performance to the Rope Pump when pumping from a range of depths, and the minimal resources needed to construct it, the EMAS Pump has potential for success in household water supply systems in sub-Saharan Africa. Combined with the conclusion from the research in Bolivia, it is believed that there is considerable potential for the EMAS Pump as a low-cost option for Self-supply systems in sub-Saharan Africa.
Recommendations for further research focus on: (1) improvements to the Pitcher Pump system (focusing on reducing risk of water contamination); (2) formative research to identify factors that have led to the sustainability of the Pitcher Pump market in eastern Madagascar, and (3) development of the Self-Supply Market in Madagascar beyond Pitcher Pump systems.
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The monopoly on water supply public service in Spain: conflicts and legal protection / El monopolio en el servicio público de suministro de agua en España: conflictos y tutelaVillar Rojas, Francisco José 10 April 2018 (has links)
In Spain, the monopoly provision of potable water supply struggles with means to obtain that resource from other sources. The viability of the public service requires mechanisms of protection against such supplies. This study analyzes the foundation and meaning of the declaration of monopoly; legal exceptions to that regime, particularly self-consumption cases; and mechanisms to protect public service provision and, if necessary, restore the monopoly and its balances. / En España, la prestación del servicio de suministro de agua potable en régimen de monopolio pugna con la existencia de medios que permiten obtener ese recurso de fuentes alternativas. La viabilidad del servicio público requiere mecanismos de tutela frente a esas conductas. El presente estudio analiza el fundamento y el significado de la declaración de monopolio; las excepciones legales a ese régimen, en particular los supuestos de autoconsumo; y los mecanismos existentes para proteger ese régimen y, en su caso, restablecer el monopolio y sus equilibrios.
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An Evaluation of the Water Lifting Limit of a Manually Operated Suction Pump: Model Estimation and Laboratory AssessmentMarshall, Katherine C. 27 October 2017 (has links)
With 663 million people still without access to an improved drinking water source, there is no room for complacency in the pursuit of Sustainable Development Goal (SDG) Target 6.1: “universal and equitable access to safe and affordable drinking water for all” by 2030 (WHO, 2017). All of the current efforts related to water supply service delivery will require continued enthusiasm in diligent implementation and thoughtful evaluation. This cannot be over-emphasized in relation to rural inhabitants of low-income countries (LICs), as they represent the largest percentage of those still reliant on unimproved drinking water sources. In that lies the motivation and value of this thesis research- improving water supply service delivery in LICs.
Manually operated suction pumps, being relatively robust, low cost, and feasible to manufacture locally, are an important technology in providing access to improved drinking water sources in LICs, especially in the context of Self-supply. It seems widely accepted that the water-lifting limit of suction pumps as reported in practice is approximately seven meters. However, some observations by our research group of manually operated suction pumps lifting water upwards of nine meters brought this “general rule of thumb” limit into question. Therefore, a focused investigation on the capabilities of a manually operated suction pump (a Pitcher Pump) was conducted in an attempt to address these discrepancies, and in so doing, contribute to the understanding of this technology with the intent of providing results with practical relevance to its potential; that is, provide evidence that can inform the use of these pumps for water supply.
In this research, a simple model based on commonly used engineering approaches employing empirical equations to describe head loss in a pump system was used to estimate the suction lift limit under presumed system parameters. Fundamentally based on the energy equation applied to incompressible flow in pipes, the empirically derived Darcy-Weisbach equation and Hydraulic Institute Standards acceleration head equation were used to estimate frictional and acceleration head losses. Considering the theoretical maximum suction lift is limited to the height of a column of water that would be supported by atmospheric pressure, reduced only by the vapor pressure of water, subtracting from this the model was used to predict the suction lift limit, also referred to herein as the practical theoretical limit, assuming a low (4 L/min) and high (11 L/min) flow rate for three systems: 1) one using 1.25-inch internal diameter GI pipes, 2) one using 1.25-inch internal diameter PVC pipes, and 3) one using 2-inch internal diameter PVC pipes. In all considered cases, with an elevation equal to sea level, the suction lift limit was estimated to be over nine meters. At a minimum, the suction lift limit was estimated to be approximately 9.4 meters for systems using 1.25-inch internal diameter pipe and 9.8 meters for systems using 2-inch internal diameter pipe, with essentially no discernable effects noticed between pipe material or pipe age. Additionally, laboratory (field) trials using a Simmons Manufacturing Picher Pump and each of the aforementioned pipe specifications were conducted at the University of South Florida (Tampa, FL, USA) to determine the practical pumping limit for these systems. Results from the pumping trials indicated that the practical pumping limit- the greatest height at which a reasonable pumping rate could be consistently sustained with only modest effort, as perceived by the person pumping- for a Pitcher Pump is around nine meters (9 meters when using 1.25-inch internal diameter GI or PVC pipe and 9.4 meters when using 2-inch internal diameter PVC pipe). Therefore, results from this research present two pieces of evidence which suggest that the practical water-lifting limit of manually operated suction pumps is somewhere around nine meters (at sea level), implying that reconsideration of the seven-meter suction lift limit commonly reported in the field might be warranted.
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An Assessment of the EMAS Pump and its Potential for Use in Household Water Systems in UgandaCarpenter, Jacob Daniel 01 May 2014 (has links)
Rural improved water supply coverage in Uganda has stagnated around 64% for a number of years and at this point more than 10 million rural people do not have access to an improved drinking water source. It has been recognized that progress toward improved water supply coverage and increased service levels may be gained through Government and nongovernmental organization (NGO) support of private investment in household and shared water supplies, commonly known as Self-supply. Self-supply can be promoted by introducing and building local capacity in appropriate and affordable water supply technologies such as hand-dug wells, manually drilled boreholes, low-cost pumps, and rainwater harvesting. Support can also be focused on technical support, marketing, financing, and strategic subsidies that promote and enhance user investment. The Uganda Ministry of Water and Environment has embraced Self-supply as a complementary part of its water supply strategy while government and NGO programs that support Self-supply have emerged.
The EMAS Pump is a low-cost handpump appropriate for use in household water systems in the developing world. There are more than 20,000 in use in Bolivia, with many constructed through Self-supply. The EMAS Pump is constructed from simple materials costing about $US 10-30, depending largely on installation depth, and can be fabricated with simple tools in areas with no electricity. The EMAS Pump is used with low-cost groundwater sources such as hand-dug wells and manually drilled boreholes or with underground rainwater storage tanks. It can lift water from 30 m or more below ground and pump water with pressure overland
or to an elevated tank. The objectives of this research were to conduct an assessment of the EMAS Pump that considers pumping rates, required energy, and associated costs, to characterize the EMAS Pump for its potential for use in household water systems in Uganda, and to make relevant recommendations.
The potential of the EMAS Pump was assessed through testing its use with 2 subject participants (male and female) on wells of 5.1 m, 12.6 m, 17.0 m, 18.4 m, 21.1 m, and 28.3 m static water levels as part of a side-by-side comparative assessment with the Family Model version of the Rope Pump, a more widely known low-cost handpump that has recently been introduced and promoted in Uganda. Shallow and deep versions of each pump were tested on selected wells for 40-liter pumping trials. The status and feasibility of low-cost groundwater development and underground storage tanks were also explored in order to help characterize the potential of the EMAS Pump as an option for low-cost household water systems in Uganda.
In general, it was observed that the EMAS Pump performed comparably to the Rope Pump in terms of pumping rates for shallow depths, but the Rope Pump outperformed it on deeper wells. It was determined that the EMAS Pump required more energy for pumping during nearly all trials. A study of relevant supply chains in Uganda concluded that the EMAS pump has a material cost that is less than 50% of the Rope Pump for most applications and 21% of the cost for shallow wells. It was also determined that the EMAS Pump could feasibly be produced nearly anywhere in the country. There are indications that low-cost wells and underground rainwater tanks are applicable in many parts of Uganda and could be paired with an EMAS Pump to achieve significant affordability for Self-supply household water systems. Recommendations are provided in terms of the feasibility of introducing the EMAS Pump as a part of Self-supply strategy in Uganda.
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Lead (Pb) Contamination of Water Drawn from Pitcher Pumps in Eastern MadagascarAkers, David Bradlee 25 March 2014 (has links)
Access to safe water supply--a major determinant of public health--is less than 50% in Madagascar, and access to piped, treated water remains out of reach financially for many in the urban and peri-urban areas where available. The Self-supply option of the Pitcher Pump has been meeting the need for household water in coastal areas of Madagascar since the early 1960s and has proven a sustainable option for many. These pumps make use of leaded components in the construction, however, which may pose a health risk for heavy metal intoxication and therefore cause the water to be unsafe for drinking and cooking. This study assesses the potential for lead (Pb) leaching from Pitcher Pump systems into water at levels of health concern. The objectives of this study are to assess Pb concentrations in water drawn from Pitcher Pumps, to determine the relationship between various factors and the Pb levels, to make a preliminary assessment of public health implications of Pb contamination, and to offer informed recommendations to reduce the likelihood of consuming contaminated water.
A field study was undertaken to measure concentrations of dissolved Pb in water from Pitcher Pumps under recently flushed and first-draw pumping conditions at 18 households in the city of Tamatave, Madagascar. Variables potentially affecting Pb leaching were determined including pump age, depth to the well screen, pump manufacturer, season of sample collection, and basic water quality indicators. Sampling campaigns were conducted three times over the course of eight months. Time-release case studies were also carried out at two households to determine the time scale over which the Pb concentration in stationary water reaches equilibrium with the Pb-containing system components. Pilot studies of iron (Fe)-for-Pb substitution of select pump system components were carried out at the same two households to attribute the major contribution of Pb leaching to one set of parts and to assess one strategy for decreasing dissolved Pb concentrations. Finally, the Internal Exposure Uptake Biokinetic Model for Lead in Children (IEUBK Model) of the US Environmental Protection Agency (EPA) was employed to estimate realistic blood lead levels (BLLs) in children under five years of age, based on Pb concentrations measured in the water.
Of the 18 pumps sampled, 15 produced at least one sample exceeding the World Health Organization (WHO) provisional guideline of 10 [um]g/L dissolved Pb in water. Specifically, 67% of all samples showed concentrations above 10 [um]g/L under first-draw pumping conditions. Flushing the pumps prior to use decreased the Pb levels significantly (p < 0.0001), with only 35% of samples exceeding the provisional guideline. Under flushed conditions, the median Pb concentration in pumped water was 9 [um]g/L, down from 13 [um]g/L at one hour of inactivity. No statistically significant correlations were observed between measured Pb concentrations and factors like the season of sample collection, pump age, manufacturer, or water quality indicators like pH or temperature. Under first-draw conditions, the concentration of Pb in water increased with increasing duration of pump inactivity, until equilibrium was reached with the leaded pump components. For two pumps, substitution of Fe valves for Pb greatly decreased Pb concentrations in the water, from 37-100 [um]g/L and 7-24 [um]g/L down to 3-4 [um]g/L and 2-8 [um]g/L, respectively. Model-predicted geometric mean BLLs in children range from about 2-8 [um]g/dL, in some instances exceeding the Centers for Disease Control and Prevention (CDC) guideline for an elevated BLL (5 [um]g/dL), depending on the exposure concentrations.
This study finds that water provided by Pitcher Pump systems in Madagascar frequently exceeds the WHO provisional guideline value for safe consumption under first-draw conditions, and may do so even after flushing the pumps. The Pb concentrations measured in the field have the potential to elevate BLLs in children under five to levels implicated in serious health issues. Leaching of Pb into the water is therefore an issue of concern for users of the Pitcher Pump systems in Tamatave, and likely for other areas served by this technology. Flushing the pumps before water collection generally reduces Pb levels in the water. These results suggest that most of the Pb leaches from pure Pb check valve weights at the mouth of the pump, and consequently, a substitution of Fe weights on the valves greatly reduces Pb concentrations and the probability for exceeding the WHO provisional guideline. Relatively simple operational changes on the part of the pump manufacturers and the pump users might, therefore, help to ensure the continued sustainability of Pitcher Pumps in eastern Madagascar.
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A comparative assessment of communal water supply and self supply models for sustainable rural water supplies : a case study of Luapula, ZambiaKumamaru, Koji January 2011 (has links)
Over the last couple of decades, a significant amount of research has been carried out on rural water supplies in developing countries, and have identified the fact that the communal water supply model is not sustainable everywhere, especially in sparsely populated rural areas; factors obstructing sustainability include lack of spare parts, management systems and private/public capacity. Despite their enormous contribution to the water sector, the extant studies stay within the subsidized communal water supply and capacity building, post construction support or management system. In other words, very few studies have been done into household (private) level water supply. The Self Supply model is an approach which provides support to households/communities to complement their efforts and accelerate sustainable access to safe water incrementally through improvement to traditional water sources (hand dug wells) by putting in their own investment. The Self Supply model may give significant benefits for sustainable safe water supplies, especially in sparsely populated rural areas, in comparison with the communal water supply though to date there has been little monitoring and systematic analysis of what impact these changes have made at the grassroots level. The standpoint of this study is pragmatic, and herein, mixing quantitative and qualitative methods was justified in order to design the research methodologies. The research was conducted in the Luapula Province of Zambia using a concurrent triangulation strategy to offset the weakness inherent within one method with the strengths of the other. The data was collected through inventory and sanitary surveys, water quality testing, household surveys, document analyses, focus group discussions and key informant interviews to determine the most appropriate water supply model for safe, accessible, sustainable, cost-effective and acceptable water supplies for households in sparsely populated rural areas of Zambia. The principal argument of this study is that reliance only on a communal water supply model limits the achievement of increased sustainable access to a safe water supply; hence a Self Supply model is needed which does not compete with the communal models but works alongside them in sparsely populated rural areas of developing countries for the purpose of increasing access and achieving sustainability. It was strongly defended by the overall findings that a Self Supply model could significantly reduce the faecal contamination risk in water quality and deliver a higher per capita water use and better convenience of access than the communal model; however its reliability with respect to the water source drying up needs to be monitored. Further, this does not mean that the communal model is not sustainable anywhere, rather that it is important to build blocks for a sustainable environment to access safe water in a symbiotic way between the communal and Self Supply models under the condition that the government and NGOs/external support agencies overcome the temptation to provide a water supply to rural dwellers as a giveaway social service.
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Assessment of Drinking Water Quality Management and a Treatment Feasibility Study for Brick by Brick Water Storage Tanks in Rakai UgandaMurduca, James V. 23 March 2018 (has links)
Reliable access to safe drinking water is one necessity for humans to live without concern for major health risks. The overall goal of this research is to improve the public health, through improved drinking water, for communities in the Rakai District in Uganda, directly, and other communities in the world, indirectly, via dissemination of knowledge. This study specifically assessed the knowledge of drinking water quality in regards to public health, their sanitation measures, and water treatment methods for users of Brick by Brick rainwater harvesting tanks in the Rakai District (N = 28) by using a knowledge, attitudes, and practice survey and a sanitary inspection; tested the water quality of the Brick by Brick rainwater harvesting tanks (N = 33) in the Rakai District for physical, chemical, and microbial parameters; and piloted a sustainable treatment technology called the chulli system that uses excess heat from a cookstove to treat water. Twenty of the participants identified contaminated water as a cause of diarrheal disease (N = 28). Participants perceived boiling (1), chlorine (2), and filtering (3) as the best three methods of treating water. The average score for the sanitary inspection was 2.27±2.31, which falls between the low and medium expected risk score categories. Fourteen of the thirty-three samples showed detectable levels of colony forming units for coliforms, and two of the thirty-three samples showed detectable levels of colony forming units for E. coli. A demonstration chulli system was constructed for St. Andrew’s Primary School in Rakai District and operated successfully. The research supports that the chulli system along with proper sanitation measures identified in the sanitary inspections can be a sustainable option for users of Brick by Brick rainwater harvesting tanks in the Rakai District.
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日本糧食問題與臺灣米穀對策之研究 (1900-1942) / The Grain Problems in Japan and the Countermeasures of Taiwanese Rice(1900-1942)森功佑, Kosuke, Mori Unknown Date (has links)
本論文是在日本帝國經濟構造的脈絡之下,來檢討日本政府跟臺灣總督府在糧食政策制定過程的互動關係,以及臺灣總督府對臺灣米穀政策之調整。本論文以此問題意識出發,有幾點問題的釐清與發現,以下分別敘述之。
日本帝國在明治維新之後邁進產業革命化,在此之後日本帝國漸漸從農業國家變成工業國家,這導致勞動者與技術者流入都市,使都市人口增加率自1890年開始慢慢增加。這些大量流入都市的人口,導致日本帝國出現米穀不足的現象。為了解決國內米穀不足的問題,日本政府開始大量進口外國米,在日俄戰爭前後每年所需的外國米就有200到500萬石。 日本帝國糧食不足的問題也使日本在1900年之後從糧食出口國變成糧食進口國。
日本政府在面對糧食不足的問題時,主要是仰賴進口外國米來解決,殖民地米的進口則是處於輔助地位。此時,臺灣總督府為因應日本帝國糧食不足的問題,從1903年開始增加臺灣米移入到日本的數量。但是,這仍無法解決日本糧食不足的問題,因為臺灣米與日本米的口感不相同,所以輸出量無法提升。為此,臺灣總督府開始進行米穀的品種改良政策。
1918年受到米騷動的影響,日本政府開始構想包含日本米與殖民地米的糧食自給政策,並於1920年正式提出以日本國內的開墾事業及朝鮮米的增殖計劃為核心的方案。但是,糧食自給政策的施行並不順利,1924到1925年間的日本還面臨外匯嚴重不足的問題,日本政府便轉為注重殖民地米的輸入。此時,臺灣開發出蓬萊米、宣告米穀品種改良的成功,在此狀況下蓬萊米輸往日本的數量亦逐年提升。因為輸出量的提升,臺灣總督府在日本政府的要求之下,從1920年後半開始擬定蓬萊米增產計劃,並在1930年的「臨時產業調查會」被提出討論。由此可知,臺灣蓬萊米在此時對於日本的糧食政策之影響力,乃隨著輸出量提升而逐漸變大。
日本帝國在經歷世界大恐慌之後,因為日本國內米穀的大豐收,導致米穀過剩的狀況出現。為此,日本政府開始管制殖民地米輸往日本的數量,並在1933年提出了「米穀統制法」,以管制日本國內的米穀供需量。但是,因為「米穀統制法」而產生的高米價不僅沒有解決日本米大豐收的問題,反而使殖民地米輸往日本的數量不斷提升,尤其是指相對低價格的蓬萊米。為了解決這個問題,日本政府於1936年實施「米穀自治管理法」,加強對於殖民地米輸往日本移出量的控管。
在臺灣方面,日本政府為了控管蓬萊米的移出,要求臺灣總督府施行「臺灣米穀移出管理令」。雖然臺灣總督府在中日戰爭爆發後,被日本政府要求必須抑制米穀耕作面積的擴大,但臺灣總督府在聽命於日本政府的同時,也隨即提出了一漸進式的米穀增產計畫。這是因為自1920年代以來,蓬萊米輸往日本的數量擴大,並在日本糧食自給政策之中扮演重要角色,從而無形中提升臺灣在日本帝國的地位。但是,當蓬萊米輸日被限制後,就意味著此一重要性的喪失,這是臺灣總督府所不願意見到,這也是為何臺灣總督府從一開始就不願意放棄蓬萊米增產計畫的原因。
在1930年代日本政府為了解決日本米大豐收的問題而開始控管殖民地米之際,雖然有法規的限制,但蓬萊米輸往日本的數量並沒有減少。此外,當日本於1936年加強對殖民地米的管制,並進一步要求臺灣總督府必須施行米穀移出管理令時,臺灣總督府在不得不聽日本政府命令的同時,卻仍提出蓬萊米增殖計劃。
透過以上問題的處理,可以看出一開始臺灣總督府在面對日本政府的糧食政策時,主要是為了配合日本人的要求及提高對日本的移出量,並因此展開米穀改良政策。從這時候看來,臺灣總督府在米穀政策的擬定上,對日本政府是處在從屬位置,這樣的情況在1922年蓬萊米開發成功之後,慢慢改變。隨著蓬萊米的開發成功,臺灣米對日本的移出量漸漸上升,又因為日本政府外匯的缺乏與糧食自給政策施展不順利,蓬萊米對日本糧食自給政策的影響力逐漸提高,這也使得臺灣總督府的立場逐漸顯現。再加上,從日本政府蓬萊米增殖計劃的提出看來,臺灣總督府表面上是聽從了日本政府的命令,但實際仍是想要進行蓬萊米的增產。而且,臺灣總督府已經從最初從屬於日本政府,轉而漸漸有自己立場出現。為了保有臺灣在日本帝國的地位,臺灣總督府甚至在日本政府的限制下,仍是持續發展蓬萊米的增產計劃。
總的來說,透過1900年到1942年臺灣總督府與日本政府在糧食政策上面的互動,可以看出日本政府在施行糧食政策的時候,乃會因著國內的糧食狀況而隨時進行調整,臺灣總督府在這個過程中所展現出來的態度,也就不是一成不變。
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Vers de nouveaux modules de puissance intégrés / Toward new integrated power modulesTran, Manh Hung 02 February 2011 (has links)
Ce travail de thèse s’inscrit dans la démarche engagée depuis quelques années et concernant l’intégration monolithique en électronique de puissance avec pour objectif de faire émerger une nouvelle structure de bras d’onduleur plus compacte, plus fiable et plus performante. En s'appuyant sur des technologies à base de transistors « complémentaires » sur substrat N et P, la nouvelle structure étudiée présente de nombreux avantages vis-à-vis de la CEM conduite, de la simplification de commande rapprochée et de la mis en œuvre. Ces aspects sont abordés et validés de manières "théoriques" et expérimentales. Le point pénalisant concernant le rendement de la structure par l’introduction du transistor sur substrat P est également analysé et de nouvelles topologies sont proposées afin d’améliorer cette limitation. Des techniques d’alimentation pour la commande bipolaire offrant un niveau maximal intégration sont ainsi développées. / The work presented in this Phd manuscript was targeted to the monolithic integration of the generic power stage of static converters with the goal of bringing out a new inverter leg structure. It is based on "complementary" transistors, N and P types, and it presents several advantages regarding the conducted EMC reduction, the simplification of the gate driver and its implementation. These aspects are studied and validated thanks to experimental results. The drawback concerning the lack of performance due to the introduction of the P type transistor is also analyzed. Several evolutions are proposed to improve the structure’s efficiency while maintaining the obtained advantages at their highest levels. Finally, bipolar gate driver supply techniques, offering high integration levels, are also developed.
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Optimisation d'une chaîne de traction pour véhicule électrique / Optimization of electronics drives for electrical car (VELECTA project)Sarrazin, Benoît 27 November 2012 (has links)
Les éléments constituant la chaîne de traction sont le plus souvent dissocies et indépendants entre eux (pack de batteries, convertisseur de traction et moteur). L'utilisation des convertisseurs en cascade en tant que convertisseurs de traction a été le cœur de ces travaux de thèse. Les performances énergétiques des convertisseurs en cascade et de l'onduleur de tension classique ont été comparées sur un cycle de conduite normalisé pour différentes configurations sur les convertisseurs de puissance (niveau de tension mis en jeu dans la chaîne de traction, variation du nombre d'onduleurs connectés en série pour les convertisseurs en cascade et variation du nombre de semi-conducteurs en parallèle pour réaliser la fonction des interrupteurs de puissance dans les convertisseurs). D'autres convertisseurs d'électronique de puissance sont nécessaires pour le bon fonctionnement d'un véhicule électrique. L'un de ces convertisseurs est le chargeur de batteries qui puise l'énergie du réseau électrique pour venir recharger les batteries du véhicule. Un autre est le système de monitoring des batteries qui permet d'assurer un équilibrage et un état de charge uniforme entre les différentes cellules qui composent le pack de batteries du véhicule. Dans une optique de mutualisation de fonction du convertisseur de puissance, les convertisseurs en cascade ont été étudiés pour assurer la fonction de chargeur et d'équilibreur lorsque la traction du véhicule n'est pas utilisée. / The elements that can be found in traction chain are usually separate and independent between them (battery pack, traction converter and motor). The use of cascaded inverter in order to drive the vehicle has been the heart of this thesis. The energy performance of cascaded inverter and classical voltage source inverter were compared on a standardized driving cycle for different power converters configurations (voltage level for the traction chain, variation of the number serial inverter for cascaded H-bridge and different number of semiconductors in parallel to do the function of the power switches in converters). Other power electronic converters are necessary for the electrical vehicle. One of these converters is the battery charger which tranfer energy from the network to the vehicle's batteries. Another is the battery monitoring system that ensures a balance and uniform state between the different cells which make up the battery pack of the vehicle. With an objective of increasing the function of the power converter, cascaded H-bridge have been designed to provide the function of charger and balance the battery cell when the traction chain of the vehicle is not used.
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