17 research outputs found
Morphological response to dredging of the Upper Gorai River
No full textThe Gorai River is a tributary of the Ganges River and is the only river in the Southwest region of Bangladesh, which provides fresh water from upstream. In the past decades the flows in the Gorai River have been decreasing. From 1988 on, the flows in the lean season were even reduced to zero, due to heavy sedimentation in the off-take. In 1996 the government of Bangladesh initiated the Gorai River Restoration Project (GRRP). The main target of the GRRP is to augment the flows in the Gorai River and to ensure flow in the dry season. Until a permanent solution can be realised, a channel is dredged during the falling stage of the water level to keep the Gorai River flowing. With the Pilot Priority Works, an immediate improvement has been realised and valuable insight into the response of the river to dredging is gained. During the dredging works data has been collected on the Gorai River and the off-take, consisting of measurements of the bed topography, water levels, discharge and sediment transport. In this report the data from April 1999 to April 2001 are used to study the morphological response to dredging. For the analysis, the GIS application ArcView with the Spatial Analyst is used. Besides a qualitative analysis, the effects of dredging are studied based on an analysis of the change in the cross-sections of the river and its effect on the discharge and the sediment transport capacity. Moreover, the sediment balance is extrapolated to include the effect of future maintenance dredging.Civil Engineering and Geoscience
Weerstand tegen stroming in de Gorai rivier
No full textIn deze studie wordt de weerstand tegen strorning in de Gorai rivier onderzocht. Als basis voor deze studie zijn veldmetingen gebruikt die gedaan zijn door een joint venture van Baggermaatschappijen onder leiding van Koninklijke Boskalis Westminister. Deze studie is gedaan in opdracht van Koninklijke Boskalis Westminister. De ruwheid is een bepalende factor in de wisselwerking tussen waterafvoer en sedimenttransport. Ook vereisen simulaties van waterbeweging en sedimenttransport middels computermodellen een nauwkeurig beeld van de ruwheid. Twee hoofdvraagstellingen worden in deze studie beantwoord: 1. In welke mate verandert de weerstand tegen strorning in de Gorai rivier gedurende dalende waterstanden. 2. In hoeverre voorspellen bestaande ruwheidvoorspellers de stromingsweerstand in de Gorai. Alvorens een samenvatting te geven van het gedane onderzoek naar weerstand tegen stroming worden eerst een aantal kenmerken en eigenschappen van de Gorairivier beschreven. De gemiddelde afvoeren van de Gorai varieren van ongeveer 50 m3/s tijdens laagwater in de maanden maart en april tot 5000 m3/s in de maanden augustus en september. Het waterstandsverschil tussen hoog en laagwater kan oplopen tot ca. 10 meter. De bedding van de Gorairivier bestaat overwegend uit zeer fijn cohesieloos alluviaal materiaal. De korreldiameter waarbij 50% en 90% gewichtspercentage van het zand een kleinere diameter heeft (D50, D90), bedraagt respectievelijk 134 en 211 micron. In de bodemmonsters wordt soms een zeer groot gewichtspercentage silt gevonden (D < 63 micron). De rivier is overwegend meanderend, maar heeft ook vlechtende kenmerken, met name in de eerste 15 km vanaf het splitsingspunt. Met het I-dimensionaal computermodel Sobek is de ruwheidsparameter onderzocht op de tijdstippen waarop de ruwheidswaarden berekend zijn. Op deze manier kan een vergelijking worden gemaakt tussen de in het model gekalibreerde ruwheidsparameter en de ruwheidsparameter berekent uit over het riviervak gemiddelde dwarsprofielconfiguraties en een aangenomen constant waterspiegelverhang. De gekalibreerde ruwheidswaarden wijken nogal eens af van berekende ruwheidswaarden. Dit is te wijten aan het feit dat in de berekening geen rekening wordt gehouden met afwijking van individuele dwarsprofielgeometrie t.o.v. het gemiddelde, wat in de Gorai vaak het geval is. Ook de aanname van constant waterspiegelverhang over een riviervak introduceert fouten in de berekening. Uit de simulaties blijkt dat het waterspiegelverhang zich concentreert over gedeelten waar het doorstroomoppervlak vemauwt. De plaats hiervan komt overeen met in het veld geobserveerde probleemlocaties. Er is ook getracht de waterbeweging te voorspellen over een korte periode van ongeveer twee weken, waarbij een vaste bodem wordt aangenomen en de gekalibreerde ruwheidswaarden constant worden gehouden. Door deze aannames blijkt het model al snel de gemeten waterstanden niet meer accuraat te voorspellen, en daarmee wordt de voorspellingswaarde gering. Tijdens het veldonderzoek in Bangladesh is getracht gegevens te verzamelen over het sedimenttransport in de Gorai en Ganges. De beschikbare gegevens van december, januari en februari zijn op een rijtje gezet. Er is geprobeerd een relatie te geven tussen stroomsnelheid en sedimenttransport per meter breedte en tussen water- en sedimentafvoer. Alleen het zwevend transport is gemeten omdat het onmogelijk bleek met de beschikbare instrumenten het bodemtransport te meten. Uit een analyse blijkt echter dat de valsnelheid van het sediment klein is t.o.v. de schuifspanningssnelheid. Daarom mag worden aangenomen dat in de morfologisch actieve periode het zwevend transportmechanisme overheerst. Het verdient aanbeveling dit te verifieren met het meten van bodemtransport. Er zijn te weinig metingen gedaan om hierop kwantitatieve conclusies te baseren. Er zijn meer gegevens over het sedimenttransport nodig om een sedimenttransportformule accuraat te kalibreren.Hydraulic EngineeringCivil Engineering and Geoscience
Discovery of the Yamato Meteorites in 1969
No full textAbstractThe first discovery of Yamato Meteorites by an inland survey team of the Japanese Antarctic Research Expedition (JARE) in 1969 was reported by Yoshida et al. (1971). However, there are important events, issues, and data related to this discovery that have so far not been published. Prior to the author's departure for Antarctica, M. Gorai suggested the author to consider collecting meteorites during the trip. On 21 December 1969, when geodetic measurements for the 250 km span of a triangulation chain were approaching its completion, members of the inland survey team collected three stones on the surface of the ice sheet in the southeastern marginal area of the Yamato Mountains. The author realized that these rocks were possibly meteorites, recalled the suggestion by M. Gorai, and requested all members of the team to collect other possible meteorites while conducting the geodetic survey. After returning to Japan, the nine stones collected in Antarctica were all identified as meteorites by M. Gorai. The concept of a mechanism by which meteorites became concentrated in the area in which they were found, involving the flow, structure, and ablation of the ice sheet, was developed in the field in 1969 during the collection program, and was mentioned briefly in Yoshida et al. (1971); a schematic figure was shown in a Japanese newspaper in the same year. With all these as background, further collections of meteorites in the Yamato Mountains were conducted in the 1973 and 1974–1975 seasons, and a project involving the collection of meteorites was formally incorporated as an important component of the work undertaken by the geology group within JARE from the 1975–1976 season onwards
Development of scientific research on problems of accounting consequences of warfare defense and building of public territories
No full textThe research analyzes the dissertation researches concerning the direction of the organization development and the methods of accounting the consequences of military actions and the occupation of state territories. The initial provisions of the dissertation research on the problems of accounting the consequences of emergencies are investigated. Analyzing the scientific novelty of dissertation research in terms of theory and methodology, the author outlines the directions of the transformation of elements of the accounting method: documenting and inventory, estimating and calculating, accounts and double entry, balance and reporting. The assessment of the current state of accounting as the system for generating the required information is made. As a result, the non-compliance of existing organizational and methodological provisions of accounting and their inability to generate information for management of economic activities in emergency situations are established
Ab-initio study of pressure evolution of structural, mechanical and magnetic properties of cementite (Fe3C) phase
No full textDevelopment of scientific research on problems of accounting consequences of warfare defense and building of public territories
No full textПроаналізовано дисертаційні дослідження, як стосуються напряму розвитку організації та методики бухгалтерського обліку наслідків бойових дій та окупації державних територій. Досліджено вихідні положення дисертаційних досліджень з проблем бухгалтерського обліку наслідків надзвичайних ситуацій. Аналізуючи наукову новизну дисертаційних досліджень в розрізі теорії та методології можна окреслити напрями трансформації елементів методу бухгалтерського обліку: документування та інвентаризація, оцінка та калькулювання, рахунки та подвійний запис, баланс та звітність. Було здійснено оцінку сучасного стану бухгалтерського обліку як системи генерування потрібної інформації. В результаті встановлено не відповідність діючих організаційно-методичних положень бухгалтерського обліку та їх неспроможність генерувати інформацію для управління господарською діяльністю в умовах надзвичайних ситуацій.The research analyzes the dissertation researches concerning the direction of the organization development and the methods of accounting the consequences of military actions and the occupation of state territories. The initial provisions of the dissertation research on the problems of accounting the consequences of emergencies are investigated. Analyzing the scientific novelty of dissertation research in terms of theory and methodology, the author outlines the directions of the transformation of elements of the accounting method: documenting and inventory, estimating and calculating, accounts and double entry, balance and reporting. The assessment of the current state of accounting as the system for generating the required information is made. As a result, the non-compliance of existing organizational and methodological provisions of accounting and their inability to generate information for management of economic activities in emergency situations are established
Accounting assessment of consequences of military operations and occupation of public territories
No full textThe article is devoted to the issues of assessing the consequences of military operations and the occupation of state territories in accounting. The analysis of the researches concerning the problems of estimation in accounting is carried out. The normative and legal regulation concerning the options for assessing the objects with which the consequences of hostilities and the occupation of state territories may be related, namely: non-current assets, current assets and receivables. The paper determines the properties of the consequences of military operations and the occupation of state territories, which must be taken into account when evaluating the accounting method as an element. The author develops the register of objects that are connected with military operations and the occupation of state territories, and the form of the act on revaluation of the object of non-current assets. The procedure for the assessing the consequences of emergencies and the occupation of state territories is proposed; the procedure takes into account the six stages and provides for the application of different types of assessment
Diversifying vegetable production systems for improving the livelihood of resource poor farmers on the East Indian Plateau
No full textFailure of the rice crop, or low rice yield has dire consequences for rice-dependent households, including food insecurity and malnutrition, for India’s poorest farmers in the East Indian Plateau region. Crop diversification could reduce the risks of rice production from the vagaries of rainfall and provide cash income which is not generated from subsistence rice. Being the primary household laborers women bear the brunt of these difficult conditions in patriarchal societies. For this reason we engaged with the women farmers in Bokaro and West Singhbhum in the State of Jharkhand, and Purulia in West Bengal who participated in experiments conducted with vegetable crops and legumes in the upland and medium uplands where the traditional crop is broadcasted paddy rice. We explored four different vegetable systems, (i) cucurbits (rainy/kharif) (season—June to September), (ii) growing tomatoes in the “off season” (rainy season—July to October), (iii) growing legume crops in rotation with direct sown rice (dry/rabi season—November to January), and (iv) intercropping beans with maize (rainy season—June to September). The results showed that all the above crops proved much better in terms of income to the farmers, return per person day, although the input cost varied it was higher with the new systems explored. The research with the small-holding women farmers enabled them to try new options and make informed decisions about these opportunities. This study showed that farmers can increase crop diversity and expand the area sown to non-paddy crops. The farmers are now looking for new crops where the demand exceeds the supply. Importantly this study has demonstrated that the direct involvement of communities’ in research enables the farmers to sustainability explore solutions to the future problems with limited support from the external agencies
Feasibility of dredging the Old Brahmaputra Off-take
No full textThe annual mean discharge of the Old Brahmaputra reduced from about 700 m3/s during the mid seventies to about 400 m3/s at the end of the nineties. Because of the on-going deterioration of the. oft-take, the Old Brahmaputra does not convey fresh water originating from the Jamuna during the lean season. By then the minor Jinjiram river, which joins the Old Brahmaputra just downstream of the oft-take, is her feeder. This results in a virtually dry river during the lean season. The paucity of fresh water in the basin of the Old Brahmaputra has severe adverse impacts on navigability, fisheries, trade, water quality, nature and agriculture. Sailing on the river is not possible anymore during a major part of the year. This hampers the transport of people and goods over water and forces transportation over land. The Old Brahmaputra is also an important migratory route for fish to and from the wetlands in the Northeast. This migratory route is cut-oft from the Jamuna during a major part of the year, and causes a decline of fish stock. As a consequence, fishery is declining and many fishermen are loosing their job. It also means that an important source of protein in the diet of the common man is lost. The lack of flushing water from the Old Brahmaputra towards the industrial areas around Dhaka is causing pollution of the surface water. Moreover, the quantity of surface water is insufficient to maintain the adjacent groundwater tables, reducing crop production and crop variation. The objective of the study is to investigate the technical feasibility of a stand alone dredging intervention in the Old Brahmaputra in order to augment dry season flows of the river. Moreover, the study should indicate environmental and socio-economic impacts of the intervention and assess costs and benefits. This study provides an answer on whether it is possible to keep the Old Brahmaputra flowing throughout the lean season by dredging only. CONCLUSIONS 1. The findings indicate that augmenting dry season flows of the Old Brahmaputra by dredging is technically feasible. The Old Brahmaputra can be kept flowing by dredging through the oft-take area, by making a connecting channel in the Jamuna (between the oft-take and a main Jamuna channel) and removing the bottlenecks in the upper reach of the Old Brahmaputra. These statements need confirmation by pilot dredging. 2. The most feasible dredging option in terms of low flow conditions and project costs is a channel with the following characteristics: Length of channel from oft-take: 60 km Theoretical estimated dredge volume: 12 Mm3 Expected minimum discharge: 50 m3/s 3. The duration of the pilot project will be about three years. The project includes two dredging seasons, a starting period for mobilisation, survey and design and a final period for survey (monitoring) and demobilisation. The probable time window for each dredging season will be about four months. 4. Prior to the design work the supporting studies, being an essential part of the pilot works will start. The objectives of these studies are to test design options and to predict impact of planned dredging interventions. 5. The AFPM type of dredging will be done in case a suitable Jamuna channel is too far away from the OB oft-take area. Then by dredging near a Jamuna bifurcation the natural morphological processes during the next monsoon should reshape the Jamuna near the oft-take towards a more favourable planform. This type of very experimental dredging will be done between the usual dredging season (Sep to Dec) and the start of the monsoon (May). 6. A first estimate of the required dredge capacity follows straightforward from the volume to be dredged, the available dredge capacity and the time window. The required dredge capacity is 3 to 4 Mm3/month or 0.7 to 0.9 Mm3/week. The available dredge capacity is assessed to amount in the OB 0.25 to 0.30 Mm3/week per medium size cutter suction dredger (Gemini type). The required number of dredgers in the first dredging season is 3 (three). Based on expected sedimentation it is expected that the works in the second dredging can be executed by deploying 2 (two) dredgers. 7. Environmental and socio-economic impacts of augmenting lean season flows are: - Re-establish migratory routes for fish and dispersion of spawn, which increases fish production and fish diversity in the Old Brahmaputra. This results in higher protein intake, security of employment and income of local population. - Increasing crop-production with positive effects on employment, variety of food and public health - Establishing navigable routes, providing year-round water borne transport along the important NW-SE corridor. - Ecological improvements resulting in an increase of the bio-diversity - Improving the water quality in the river thus improving public health 8. The costs of pilot dredging as outlined above amount to some MNLG 40 per year, during 3 years. The main benefits are expected to come from the sectors fisheries, agriculture and navigation (see previous point). First assessments show that costs and benefits are of the same order of magnitude. 9. Pilot dredging can only be successful when executed independently as a design-and-construct project. Also, 'Main Studies' are necessary to analyse other methods (e.g. structures combined with dredging) to improve the river conditions in the long term (comparable with the Gorai projects), Running the pilot dredging and Main Studies simultaneously with strong interrelations will be profitable for both projects
