521 research outputs found
Bumper crops, producer incentives and persistent poverty
Food aid has played a useful role in Government of Bangladesh efforts to increase food security in the last three decades, adding to foodgrain availability, supplying wheat for targeted distribution to poor households, and helping to finance development projects and programs. However, sustained increases in domestic production of both rice and wheat have increased the likelihood of disincentive effects arising from continued large inflows of food aid. The analysis shows that if good rice harvests continue so that real rice prices remain at their levels of 2000, and if international wheat prices return to their average 1995-99 levels, then public wheat distribution may need to be cut to levels below the current amount of food aid received (650 thousand tons in 2000/2001) to avoid reducing domestic prices below import parity. However, resources will continue to be required for programs that increase access to food by the poor, contribute to increased utilization of food and result in improved nutritional outcomes, even if the need for food aid to increase availability of foodgrains diminishes.Food relief Bangladesh. ,Food security. ,Development projects. ,Rice Prices Bangladesh. ,Wheat Prices. ,
Study of areas and development strategy for regional planning in East Pakistan.
Massachusetts Institute of Technology. Dept. of City and Regional Planning. Thesis. 1965. M.C.P.Bibliography: leaves 178-180.M.C.P
A Chain Oriented Data Collection Protocol for Energy-Aware and Delay-Constrained WSN
Energy awareness plays an important role in
developing routing protocol for the battery powered wireless sensor networks. As the replacement of the battery is often unfeasible in practical situations, we present here an optimal solution for the maximum utilization of precious available energy at the same time trying to minimize the latency in data delivery. We propose to form hierarchical chains with deployed sensors to collect information from a
target field where data get fused at every node level before transmitted finally. Our protocol utilizes the higher energy nodes for more frequent long distance transmissions so that the energy expenditure become even between all nodes in the network irrespective of their physical locations. It has been found in our simulation that this protocol outperforms other hierarchical protocols like LEACH and PEGASIS in both the cases of energy consumption and time requirements respectively. It has been also found that the overall lifetime of the sensor network also increases in our protocol
Prospective study on quality of newborn care
Background: Quality of services provided by health care provider, the closest health functionary to the community has impact on neonatal mortality. Aims: Study on quality of newborn care in rural areas. Settings and Design: This is a prospective study in the field practice areas of J.N. Medical College and areas under primary health centre of public health care system in Wardha district. Methods and Material: Modified quality check list on the basis of PHC MAP module guidelines for assessing the quality of service-module 6-user’s guide was prepared. Face to face interview with 205 (group-A/104 nos + group-B/101 nos) mother of newborn was method to collected information in three postnatal visits. Statistical analysis: Quality (verbal response) of each service was quantified as acceptable, average and worst. Quality of both the groups was compared by calculating P-value after utilizing Z-test. Results: Over all acceptable quality of medical history was 30.03%, physical examination was 21.73%, preventive service was 91.17% and counseling was 24.83%. Significant difference between two groups were found on history taking for (cry, breathing and body movement of baby), recording weight and counseling regarding exclusive breast feeding for first 6 month of life. Worst quality in this study were observed in history for anything applying to eyes, umbilical cord stump and complication of baby for which appropriate management was taken. Except for weight recording and examination of head and fontanels all other variables under physical examination were not acceptable. Counseling regarding high risk condition of baby was only 13.66%. Conclusion: Existing newborn services except immunization is inadequate and needs to be strengthened especially physical examination and counseling services
Effect of laser parameters on colour marking of Ti6Al4V titanium alloy
Colour laser marking is a contemporary method for adding colours onto metal surfaces, suitable for creating logos, barcodes, metal crafts, and jewelry. This study focused on colour laser marking on the biomedical alloy Ti6Al4V (TC4), examining how different colours manifest on its surface. Power settings ranged from 9 W to 18 W, while frequencies spanned 500 kHz to 2000 kHz. The research investigated how altering laser frequency and defocus distance influenced colour variation. Surface features were assessed using 3D optical microscopy, revealing texture and roughness traits. Results illustrated a spectrum of colours, shifting from the alloy's original silver hue to shades like blue, gold, orange, shiny silver, violet, and several greys. Each colour displayed distinct surface texture and roughness parameters. The highest mean roughness of 2.504 μm occurred with grey, while silver had the lowest at 0.504 μm. Nevertheless, trends differed when measuring parameters like maximum peak-to-valley height and valley depth, emphasizing surface topography's role in colour effects. This research advances the understanding of colour laser marking's intricacies on TC4 alloy, providing insights into optimizing laser settings for specific colour outcomes and underlining the nuanced relationship between colour, texture, and surface characteristics
Enhancement of laser heating process by laser surface modification on titanium alloy
Titanium alloys are widely utilized in laser heating applications. However, it has poor optical properties due to low laser energy absorption. Nevertheless, a higher energy absorption can be realized by modifying the surface profile through increasing the surface roughness. In this present work, the laser surface modification (LSM) process was carried out to increase the roughness on surface of Ti6Al4V titanium alloy. Subsequently, the surface characterization and surface roughness were analysed by using the 3D optical microscope. The effect of laser power on the increment of surface roughness was investigated. It was revealed that an increase in laser power during LSM process could increase the surface roughness. The result shows that, the surface roughness of titanium alloy increased 27 times when modified with the highest laser power (27W) compared to the gritted surface. Furthermore, the modified surface by LSM will be heated using laser radiation in order to analyse the effect of surface roughness towards laser heating temperature. Depending on the value of the power during laser heating, the maximum temperature measured could be increased 27% corresponding to a gritted flat reference surface
Effect of laser surface modification on SS316L surface roughness and laser heating temperature
Nowadays, stainless steel is widely used in laser processing applications, including laser heating, laser brazing, and laser welding. However, it has poor optical properties due to low laser energy absorption. However, this could be improved with the aid of laser surface modification (LSM). The significance of this work is to examine the influence of LSM laser power on the surface roughness of 316L stainless steel samples. First, the LSM laser power was varied from 15 to 27 W. Then, the surface topography and variation of the surface roughness values were examined by using a 3D optical microscope. Furthermore, the modified surface by LSM will be heated using laser radiation in order to analyze the effect of surface roughness towards laser heating temperature. The result revealed that as the LSM power increased, thereby resulting in an increase of surface roughness. The highest LSM laser power (27 W) produced the highest surface roughness with 28.98 μm. Experimental results illustrate that the heating temperature were increased 36%, corresponding to a polished flat reference surface, which indicates the increment in energy absorptivity
Influence of laser surface texturing (LST) parameters on the surface characteristics of Ti6al4v and the effects thereof on laser heating
With rapid growth in laser-based manufacturing technologies, laser brazing has attracted significant attention in various industries such as automotive, biomedical and aerospace. Material heating in laser brazing is one of the factors to ensure maximum reaction between the filler and the base metal. During laser heating the energy needed to melt the filler is also dependent on the laser-material interaction, so in this work the effect of laser surface texturing (LST) parameters such as power, pulse frequency and scan speed on the surface morphology and roughness properties of Ti6Al4V were investigated using a fibre laser. It was found that an increase in laser power accompanied by a decrease in frequency and scan speed could increase the surface roughness. Additionally, the effect of surface roughness towards laser heating temperature was also studied with a fibre laser. When laser beam radiates a rougher surface the maximum temperature attained is 41.4% higher compared to a polished surface. This was mainly due to the laser energy scattering over a larger and rougher surface area causing amplification of the energy absorption in the form of temperature rise
Comparative study between furnace brazing and laser brazing
Nowadays, brazing has been widely used in many industries, especially in the automotive application. The brazing process is introduced as it can be used to join the different metals together without melting the parent material. In this present study, furnace brazing and laser brazing of Ti-6Al- 4V titanium alloy and 316 L stainless steel (SS) with silver-based, BAg 8-1.5Ti filler metal were studied. There are significantly different between furnace brazing, also known as conventional brazing method and laser brazing in terms of joining strength and microstructure reaction. Furnace brazing was performed at 870°C and 880°C with 30 minutes of heating duration. Meanwhile, laser brazing was performed using a 200Watt continuous wave laser with varying laser power. Both of brazing method was conducted with a vacuum pressure of 3×10−3 Pa. Besides, to maintain the accuracy of the temperature measurement of laser brazing, an infrared thermometer is used. The tensile test was conducted to analyse the mechanical properties. The cross-sections of the brazed joints have been examined using an optical microscope. The brazed joints of the furnace brazing show an average tensile strength of 55.89 kPa for 880°C and 43.16 kPa for 870°C. Nonetheless, the maximum tensile strength of laser brazed joints was 27.95 kPa, which is lower than furnace brazed joints
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