Studies on morphometry and hydrology of Gandhisagar Reservoir with special reference to its fisheries

Gandhisagar, the second largest reservoir of India is located in Mandsaur district of Madhya Pradesh at latitude 24°44'N and longitude 75°33'E at an altitude of 403.56m MSL in orientation from NE to SE. It has an extensive water spread area of 66000 ha at full reservoir level with a maximum and mean depth of 49.52 and 11.73 m respectively. The maximum length and width of the reservoir are 112 and 16km having a total shore line of 442km. Details of catchment area, bathymetry, standard hydrological data giving water level relation of the basin to water spread area, volume and fish production and the bottom topographical details of 11 experimental fishing stations and 6 fish landing centres are discussed.

Increase in fish production achieved by stocking exotic species (Lake Kyoga, Uganda)

The Lake Kyoga complex lies towards the north of Uganda, at 311 altitude of 3,400 feet, between 10 and 2° north of the Equator. The lake is extremely elongate and digitate, shallow (1 metre-7 metres), and almost all the coast-line is swampy, with many papyrus beds. Floating islands of sud are a feature. At its eastern extremity, it breaks up into many swampy, isolated lakes. The Nile from its source at Jinja enters Lake Kyoga on its southern side, and leaves the lake at its western extremity, and winds on through to Lake Albert and the Sudan. The Kyoga/Salisbury /Kwania complex covers 2,354 sq. km. of water. Geologically, the lake is a series of flooded river valleys, probably resulting from the uplifting of the western edge of the basin in the Pliocene and the Pleistocene ages aud the endemic fish fauna is very similar to that of Lake Victoria, although Kyoga has not developed the species flocks of haplochromis which characterise the larger lake. The Victoria fauna extends down-stream of Lake Kyoga to the Murchison Falls on the Nile, which forms an almost complete barrier between Kyoga and the typical nilotic fauna of the Nile below Murchison and Lake Albert.

La peche dans le fleuve Niger

The fish production of the River Niger can best be estimated from a country by country evaluation of the tonnage exported and that consumed locally. All exported and some locally consumed fish are preserved by smoking or sun drying, a process which entails a loss of weight. Coefficients to correct for this of between 2.6 to 4 have been calculated depending on the type of product. A further loss occurs due to handling and to insect attack, which may account for up to 40% of the production. Taking the above factors into account the productions estimated for the various countries of the Niger River basin are as follows: Guinea (3,600 t), Mali (90,000 t), Upper Volta and Ivory Coast (negligible), Niger (5,200 t), Dahomey (1,200 t), Nigeria (25,000 t), Cameroon (3,000 t). A total production of 128,000 t is, therefore, obtained for the basin as a whole, excluding the Kainji Reservoir. At this level of production, there have been no intimations of overfishing from any part of the basin, and there is unanimity that fishing could be intensified. On the basis of the estimates of existing production and local estimates of potential production it is possible that up to 200,000 t of fish could be produced annually from the basin as a whole.

Minimalistic control of biped walking in rough terrain

Toward our comprehensive understanding of legged locomotion in animals and machines, the compass gait model has been intensively studied for a systematic investigation of complex biped locomotion dynamics. While most of the previous studies focused only on the locomotion on flat surfaces, in this article, we tackle with the problem of bipedal locomotion in rough terrains by using a minimalistic control architecture for the compass gait walking model. This controller utilizes an open-loop sinusoidal oscillation of hip motor, which induces basic walking stability without sensory feedback. A set of simulation analyses show that the underlying mechanism lies in the "phase locking" mechanism that compensates phase delays between mechanical dynamics and the open-loop motor oscillation resulting in a relatively large basin of attraction in dynamic bipedal walking. By exploiting this mechanism, we also explain how the basin of attraction can be controlled by manipulating the parameters of oscillator not only on a flat terrain but also in various inclined slopes. Based on the simulation analysis, the proposed controller is implemented in a real-world robotic platform to confirm the plausibility of the approach. In addition, by using these basic principles of self-stability and gait variability, we demonstrate how the proposed controller can be extended with a simple sensory feedback such that the robot is able to control gait patterns autonomously for traversing a rough terrain. © 2010 Springer Science+Business Media, LLC.

Discharges and sediments as sources of extracellular alkaline phosphatase in a shallow Chinese eutrophic lake

Total alkaline phosphatase activity (APA) and soluble reactive phosphorus (SRP) concentrations were measured in municipal wastewater, and a shallow Chinese freshwater lake receiving it. Activities of Dissolved alkaline phosphatase ( ADAP) in overlying and interstitial water were also analyzed monthly at three sites for several years. The lake was enriched with SRP and alkaline phosphatase by discharge of the wastewater, indicating that the inclusion of APA for estimating water pollution was reasonable. Annual data showed that APA in coarser fraction was significantly higher at the site receiving more wastewaters, both in surface and overlying water, suggesting that resuspension of enzyme most likely occurred in the basin heavily discharged. ADAP was an order of magnitude higher in the wastewater than those in lake waters, and was generally higher in interstitial water, a feature more striking at the site receiving more discharges. Besides, it was irrespectively inhibited by Na2WO4, L-cysteine and EDTA-Na, but stimulated by Cu2+, Zn2+, CTAB and Triton X-100 in interstitial, overlying and surface waters. This similarity of responding patterns to the stressors indicated an analogy between dissolved alkaline phosphatase in water column and that in interstitial water, supporting the hypothesis that the polluted sediments act as source of dissolved alkaline phosphatase in eutrophic lakes.

多层企业应用的关键:J2EE应用服务器

Application server provides a platform that helps users to create,deploy,execute,integrate and maintainmulti-tier enterprise applications. This paper analyzes a variety of implementation strategies of application servers,th eh gives evaluating features for J2EE application server and compares the 4 representative products.

Analysis of orthogonal memory patterns

It is well known that the storage capacity may be large if all memory patterns are orthogonal to each other. In this paper, a clear description is given about the relation between the dimension N and the maximal number of orthogonal vectors with components +/-1, and also the conception of attractive index is proposed to estimate the basin of attraction. Theoretic analysis and computer simulation show that each memory pattern's basin of attraction contains at least one Hamming ball when the storage capacity is less than 0.33N which is better than usual 0.15 N.

Characteristic rainfall for warning of debris flows

A characteristic rainfall is introduced to overcome the difficulties encountered in determining a critical rainfall value for triggering debris flow. The characteristic value is defined as the rainfall at which debris-flow occurrence probability shows a rapid increase, and can be used as a warning rainfall threshold for debris flows. Investigation of recorded debris flows and 24-hour rainfall data at Jiangjia basin, Yunnan Province, in southwestern China, demonstrates the existence of such a characteristic rainfall. It was found that the characteristic rainfall corresponds to the daily rainfall of 90% cumulative probability by analyzing the basin's daily rainfall histogram. The result provides a simple and useful method for estimating a debris-flow warning rainfall threshold from the daily rainfall distribution. It was applied to estimate the debris-flow warning rainfall threshold for the Subaohe basin, a watershed in the 2008 Wenchuan earthquake zone with many physical characteristics similar to those of the Jiangjia basin.

A Unified Tensor Level Set for Image Segmentation

This paper presents a new region-based unified tensor level set model for image segmentation. This model introduces a three-order tensor to comprehensively depict features of pixels, e.g., gray value and the local geometrical features, such as orientation and gradient, and then, by defining a weighted distance, we generalized the representative region-based level set method from scalar to tensor. The proposed model has four main advantages compared with the traditional representative method as follows. First, involving the Gaussian filter bank, the model is robust against noise, particularly the salt-and pepper-type noise. Second, considering the local geometrical features, e. g., orientation and gradient, the model pays more attention to boundaries and makes the evolving curve stop more easily at the boundary location. Third, due to the unified tensor pixel representation representing the pixels, the model segments images more accurately and naturally. Fourth, based on a weighted distance definition, the model possesses the capacity to cope with data varying from scalar to vector, then to high-order tensor. We apply the proposed method to synthetic, medical, and natural images, and the result suggests that the proposed method is superior to the available representative region-based level set method.

东北亚构造-盆地演化及油气资源控制作用

The oil and gas potential of Northeast Asia is enormous, but the degree of exploration is very low in Northeast Asia (the degree is below 3%-10%).The reasons are as follows: First, it is relatively difficult to study the oil and gas bearing basins(OGB), which are of multiple types, in different tectonic settings, with complex geologic frameworks and with long-term geologic evolution. Secondly, because of the non-equilibrium in development of economy and regional market, application of theories and techniques and the research levels in different countries, the conclusions are not conformable, and even contradictory. Thirdly, most of the former researches were limited to one territory or one basin, and lack of systematical and in-depth study on geotectonic evolution, classification of basins, and the evaluation of hydrocarbon resources. In this thesis, integrated study of the regional tectonic feature and basin features of Northeast Asia was done, to understand the basin evolution history and the controlling action on oil and gas. Then, new conclusions are and exploration proposals are as following: 1. Geotectonic evolution in Northeast Asia: The main structural motion system in Paleozoic Era was longitudinal, and in Meso-cenozoic was latitudinal with the Pacific Ocean. The whole evolution history was just the one of pulling-apart, cutting-out, underthrusting and collision of the Central Asia- Mongolia Ocean and the Pacific Ocean. 2. The evolution characteristics of basins in Northeast Asia: mainly developed from longitudinal paste-up, collision and relaxation rifting motion in Paleozoic-Early Mesozoic Era and from underthrust, accretion, and receding of subducted zone of the Pacific Ocean in Late Mesozoic Era-Cenozoic Era. 3. The research in basin classification of Northeast Asia: According to geotectonic system, the basins can be classified into three types: intracratonic, pericratonic and active zone basin. And they can be further classified into 18 different types according to genetic mechanism and dynamic features. 4. The master control factors of oil and gas accumulation in Northeast Asia: high quality cap-rock for craton and pericrationic basin, the effective source rock and high quality cap-rock for Mesozoic rifted basins, intra-arc, fore-arc and back-arc basins. Graded exploration potential of oil and gas for basin in Northeast Asia according to 7 factor, hereby, divided the oil and gas potential of basins into 5 levels. 5. Evaluation of hydrocarbon resources: The difference of resource potential among these basins is huge in Northeast Asia. The evaluation of Mesozoic rifted basin and Pacific Ocean basin showed that the large scale rifted basin and retroarc basin(including backarc marginal sea basin) have great resource potential. 6. The writer believes that the next step should pay more attention to the evaluation of petroleum resource in Far East part of Russia and trace them. On the other hand, according to integrated analysis of oil/gas resource potential and the operation difficulty in this area, suggests that East-Siberia basin, East-Gobi-Tamchag basin, Sakhalin basin, North-Okhotck basin, West-Kamchatka basin could be as cooperation priority basins in future.

柴达木盆地西区新生代构造演化

The Qaidam Basin constitutes a major portion of the northeastern Tibetan Plateau, and an understanding of its tectonic development will help decipher how the Tibetan Plateau was formed. It is shown that Late Cretaceous–Paleocene deposits of the western Qaidam Basin can be well correlated with their counterparts of the southwestern Tarim Basin, implying that the two regions were originally connected or were in the same depositional basin during that period of time. The Qaidam Basin commenced subsiding due to crustal shortening in the Eocene, and it has subsequently evolved into an independent basin since the Miocene. The main depocenter was noticeably persistent in the middle of the western Qaidam Basin from Eocene to Miocene time, and then it shifted to the east. On the basis of spatial stratigraphic correlation and restoration of sedimentary processes, we surmise that there existed a proto–Qaidam Basin during the Paleogene, where the Suhai and Kumukol Basins represent its northern and southern margins, respectively. The Suhai and Kumukol Basins were subsequently isolated from the Qaidam Basin as a result of basinward thrusting in basin-margin areas. It is shown that the western Qaidam Basin experienced three distinct stages: the first stage was characterized by a simple synclinal depression; the second stage was marked by occurrence of reverse faults at inflection points of the megafold and continuous subsidence in the middle of the basin; and the third stage featured intrabasinal deformation and uplift. The eastern Qaidam Basin underwent a diverse evolution and became the main depositional area in the Quaternary. It is suggested that the Qaidam Basin should be generated as a result of crustal buckling or folding, manifesting itself as a synclinal depression. The crustal folding model can account for a number of observations, including localization of the depocenter in the middle of the basin, nearly concomitant deformation on the south and north sides of the Qaidam Basin, occurrence of major high-angle reverse faults at basin margins, and generation of adjacent intermontane Suhai and Kumukol Basins. A tectonic model is accordingly advanced to illustrate Cenozoic tectonics of the Qaidam Basin.

元谋盆地河湖相沉积记录的上新世印度季风转型事件

The Indian monsoon, an integral part of the global climate system, has been extensively investigated during the past decades. Most of the proxy records are derived from marine sediments and focused on time periods of the late Miocene and Pleistocene. The Pliocene represents a period when Earth’s boundary conditions underwent dramatic changes. However, variations of the Indian monsoon during the Pliocene and its forcing mechanisms have remained unclear. The Yuanmou Basin, located in the region of the Indian monsoon, provides an ideal target for understanding the Pliocene history of Indian monsoon variations. Detailed investigations on the lithostratigraphy, magnetostratigraphy and limnology of a 650-m-thick fluvio-lacustrine sedimentary sequence from the basin are carried out in the present study. The clay and clay-plus-fine-silt fractions of the sediments are referred to the midlake-facies components, and changes in the percentages of both fractions generally reflect changes in the water level of the lakes developed in the basin closely related to variations in the intensity of the Indian monsoon. Whereas the greenish-gray lacustrine mud beds represent the environment of deep-water lakes, and the frequency of individual lacustrine mud beds is considered to indicate the frequency of the deep-water lakes developed in the basin associated with the variability of the Indian monsoon. The proxy data suggest that the Indian monsoon experienced abrupt shifts at 3.53, 3.14, 2.78 and 2.42 Ma, respectivey. 1) Since 3.53 Ma, the midlake-facies components displayed a general trend of increase in the concentrations, accompanied by an increase in the sedimentation rate from an average ~10 to 25 cm ka–1. The data suggest that high stands of the lakes in the basin rose progressively, implying a gradual intensification of the Indian monsoon since that time. This shift occurred coeval with the accelerated uplift of the northern Tibetan Plateau, denoting a close link between the Indian monsoon strengthening and the Tibetan Plateau uplifting. 2) 2.78 Ma ago, the concentrations of the midlake-facies components decreased abruptly and the dominant fraction of the sediments turned to fluvial sands. The data indicate that lakes in the basin disappeared, reflecting a dramatic decline in the intensity of the Indian monsoon at that time. This shift coincided with the formation of extensive Northern Hemisphere ice sheets, implying a quick response of the low-latitude monsoon regime to the high-latitude glaciation. 3) At 3.14 Ma, the initial appearance of blackish-grey mud beds with long durations and occasional occurrences of lacustrine mud beds indicate that the basin was overall dominated by shallow lakes, implying a shift to decreased variability of the Indian monsoon at that time. At 2.42 Ma, an increase in the frequency and a decrease in the duration of the lacustrine mud beds suggest that deep-water lakes were frequently developed in the basin, denoting a shift to increased variability of the Indian monsoon at that time. The former shift coincides with the onset of large-scale glaciation in the circum Atlantic region and the latter corresponds to the inception of predominance of the 41 ka periodicity in Northern Hemisphere ice-sheet cover fluctuations, presumably suggesting a physical link between the Indian monsoon system and the high-latitude ice sheets in the Northern Hemisphere.

油气勘探中的弱磁异常提取与区域场分析

Petroleum and natural gas is an important strategic resources. The short of the reserves will block the development of economy and threaten the safety of nation, along with the main oil fields of our country coming to the height of power and splendor of the exploitation and exploration. Therefore, it makes a great sense to inaugurate new explorative field and increase the reserves of petroleum and natural gas. Magnetic exploration is a main method of geophysics exploration. the developing observation apparatus and the perfect processing method provide wide space for magnetic exploration in these years. The method of magnetic bright spot is an application of magnetic exploration. The vertical migration of the hydrocarbon changes physical and chemical environment above the hydrocarbon reservoir, the new environment make tervalent iron translate into bivalent iron, that produce small scale magnetic anomaly, that is magnetic bright spot. The method of magnetic bright spot explores oil and gas field by the relation between the hydrocarbon and magnetic anomaly. This paper systemically research to pick-up and identify magnetic bright spot combining an oil field item, then point out advantaged area. In order to test the result, the author use the seismic information to superpose the magnetic bright spot, that prove the magnetic bright spot is reliable. then, the author complete a software to pick and identify the magnetic bright spot. The magnetic basement is very important to research forming and evolvement of the basin, especially, it is a crucial parameter of exploring residual basin in the research on pre-Cenozoic residual. This paper put forward a new method to inverse the interface of the magnetic layer on the basis of previous work, that is the method of separation of magnetic field step by step. The theory of this method is to translate the result of magnetic layer fluctuation to the result of magnetization density change, and the magnetic layer is flat, the paper choose thickness of magnetic layer as unit thickness, and define magnetic layer as a unit-thickness layer in order to convenient calculation, at the same time, define the variational magnetization density as equivalent magnetic density. Then we translate the relation between magnetic field and layer fluctuation to the relation between magnetic field and equivalent magnetic density, then, we can obtain the layer fluctuation through calculating equivalent magnetic density. Contrast to conventional parker method, model experimentation and example checkout prove this method is effective. The merit of this method is to avoid flat result in a strongly fluctuant area because of using a uniform average depth, the result of this method is closer to the fact, and this method is to inverse equivalent magnetic density, then translate equivalent magnetic density to layer fluctuation, this lays a foundation to inverse variational magnetic density in the landscape orientation and portrait.

柴达木盆地北缘西段油气运聚动力学研究

Hydrocarbon migration and accumulation are the important process to form reservoirs in sedimentary basins, and their researches are usually very difficult to be done in petroleum geology. In this paper, the west segment of northern margin of the Qaidam Basin was selected as study area. The concept of fault open coefficient, that combines multi-factors dealing with fault sealing, was applied to estimate semi-quantitatively the sealing characteristics of six faults which were considered controlling the hydrocarbon migration and accumulation. The data from boreholes were investigated to appraise the permeable characteristics of lithology combinations upon and beneath the unconformity surface. The result suggests that the basal conglomerates consist frequently the carriers. The data from boreholes and outcrops were collected to describe the sand carrier system. In order to eliminate the influence of inverse activities of the basin that made the formations be very steep, author adopts the phase method to build the basin models: for the steps before Pliocene the recovered true thickness maps were used to build the basin block; for the steps after Pliocene, the structure maps of today were used to build the basin block. During the modeling process, the results were calibrated by various measured data . the modeled results includes the dynamic evolvement course of trap form phase, vitrinite reflectance mature, the source rock expelled hydrocarbon intensity and fluid potential and petroleum plays. Author integrates the source rock expelled hydrocarbon intensity, fluid potential and carrier system and apply the migration technology based on percolation theory to simulate the oil and gas migration and accumulation course in the main accumulation times. The dominant pathways of oil and gas may show clearly the prospect distribution. Based on the hydrocarbon migration characteristics, the main control factors were synthesized, that including the effective source rock distribution, the match relationship of structural trap forming and hydrocarbon expelling from source rocks, the unconformity of Mesozoic and Cenozoic, the structures and the faults movement at Quaternary Finally, the author figures out the prospect plays in the study area.

辽河盆地西部凹陷深部流体的地球化学特征与成藏效应

The main research area of this thesis is the Western Depression in the Liaohe Basin. Based on the drilling core observation and mud logging data, the features of the mantle–derived fluids and their effects on oil/gas generation in the Western Depression of the Liaohe Basin,was studied with comprehensive methods of volcanic petrology, sediment petrology, fluid geochemistry, sedimentlogy, and structural geology, and use of polarized light microscope, fluorescence microscope, electron microscope, fluid and melt inclusion test, and isotopic test of nature gas etc. The observation of drill cores in study area and other studies reveal that the main passageway of the volcanic eruption in the Cenozoic was the Xibaqian-Gaosheng fault, and the volcanic rocks of each stage were distributed around it. Mantle-derived fluid which affected on oil/gas generation formed later than the volcanic spew and those fluids entered into the depression through the Taian-Dawa fault and the Central fault. The volatile fraction analysis of the melt inclusion reveals the presence of two kinds of mantle fluids; they are hydrogen-rich fluid and carbon dioxide-rich fluid. These the two kinds of fluids were mainly distributed in olivine and pyroxene respectively. The hydrothermal veins development have multiple stages, from high temperature quartz vein to low temperature calcite vein and analcime vein, in which the fluid inclusion extremity component are methane and carbon dioxide, which indicate that when mantle-derived fluids ascended and entered into the basin, most of these fluids interacted with the organic matter in the basin even though some of these entered into atmosphere. The present isotopic test of the nature gas reveals the high 3He/4He value between the region of the Taian-Dawa fault and the Central fault, which also imply the feature of origin in mantle. This phenomenon indicates that the Mesozoic basement faults and the main Cenozoic faults had connected crust and the mantle during the basin evolution, so the mantle derived fluids could enter the basin along those faults. The main source rocks of the ES3 and ES4 members of the Shahejie Formation began to expel hydrocarbon at the end period of the ES1 member of the Shahejie Formation, and reached its peak during the period of the Dongying Formation deposition. During these periods, the mantle derived-fluids entered the basin constantly along the main faults, and supplied lots of hydrogen for hydrocarbon generation. Though the volcanic rocks and the mantle-derived fluids in the Eastern Depression were more developed than in the Western Depression, the source rocks and the deep fluids were not interacted better than the Western Depression because of the affection of structural evolution. In the Eocene, the Eastern Depression did not deposit the ES4 member of the Shahejie Formation, furthermore, the mantle-fluid formed in the Fangshengpao stage escaped to the atmosphere, which confined the later stage hydrocarbon generation capability.