Vegetation mapping in solving environmental problems

2013 ◽  
pp. 3-31 ◽  
Author(s):  
A. V. Belov ◽  
L. P. Sokolova

This paper presents the stages of cartographic study into vegetation of Baikalian Siberia (the southern part of East Siberia). It highlights the ways toward shaping the principles and methods of the Irkutsk (Siberian) school of mapping vegetation as a component of geosystems, the founder of which was Academician V.B.Sochava. The initial stage in studying vegetation of Baikalian Siberia involved cartographic support of the resolution of ecological problems within national programs of integral development and exploitation of natural resources in the country’s eastern regions. The current stage of cartographic study into vegetation of Baikalian Siberia is determined by changes in the nature management paradigm in circumstances where the market economy is being shaped. This stage is characterized by the transition from general purpose-regional small-scale universal mapping to generation of medium- and large-scale assessment-forecast maps of vegetation for ecological accompaniment of a variety of economic measures, such as development of oil and gas fields in the Prebaikalia, an enhancement and promotion of recreation at Baikal, etc. Presented is the algorithm of geobotanical forecasting as a multistage process of conjugate mapping of vegetation. Using the key areas on the Angara-Lena interfluve and in Northern Priolkhonie as an example, different aspects of anthropogenic and natural stability of vegetation are considered from the perspective of geobotanical forecasting. The economic value of vegetation is determined according to its ecologo-protective and resource potentials. Recommendations are made for nature management optimization on a forecasting-geobotanical basis.

2013 ◽  
Vol 421 ◽  
pp. 917-921
Author(s):  
De Xun Liu ◽  
Shu Heng Tang ◽  
Hong Yan Wang ◽  
Qun Zhao

Affected by the constant development of global economy and the imbalance in distribution of conventional oil and gas, oil and gas resources can no longer meet the demand in many countries. Development of unconventional oil and gas has begun to take shape. Shale gas and tight oil become the focus of global attention. Unconventional oil and gas resources are relatively abundant in China. Preliminary results have been achieved in the development of shale gas. Tight oil has been developed in small scale, and the main technologies are maturing gradually. Yet we face many challenges. Low in work degree, resources remain uncertain. Environmental capacity is limited, and large scale batch jobs will confront with difficulties.


Forests ◽  
2018 ◽  
Vol 9 (11) ◽  
pp. 701 ◽  
Author(s):  
Lorenzo Sallustio ◽  
Marco di Cristofaro ◽  
Maaz Hashmi ◽  
Matteo Vizzarri ◽  
Tommaso Sitzia ◽  
...  

Land use by humans strongly alters the landscape mosaic, either by reducing or increasing its heterogeneity. One of the most recent and widespread land use changes in Europe has been the spontaneous reforestation of marginal agricultural lands. These primarily affected small landscape patches, such as trees outside forests (TOF) and small open areas (SOA), often represent the most diversifying features of landscape’ structures. Nevertheless, only small-scale studies can be found in the literature and thus it remains a relatively unexplored issue. Integrating inventory and cartographic approaches, this work assesses changes in abundance, coverage, and average size of small patches in Italy between 1990 and 2013. Main results showed an overall increase in number and coverage of small patches during the reference period. The average patch size remains unaltered for TOF but decreases significantly for SOA, due to trees encroachment and canopy cover increasing in forests. Our findings confirm the important changes in Mediterranean land mosaics and contribute to a better understanding of current conditions and recent trends regarding TOF and SOA. The integrated approach has proven to be helpful for the large-scale assessment of small patches dynamics, representing a viable monitoring tool to encourage the inclusion of small patches in landscape policy and planning.


Author(s):  
M. T. Rahmati ◽  
G. Alfano ◽  
H. Bahai

Flexible risers which are used for transporting oil and gas between the seabed and surface in ultra-deep waters have a very complex internal structure. Therefore, accurate modeling of their behaviour is a great challenge for the oil and gas industry. Constitutive laws based on beam models which allow the large-scale dynamics of pipes to be related to the behaviour of its internal components can be used for multi-scale analysis of flexible risers. An integral part of these models is the small-scale FE model chosen and the detailed implementation of the boundary conditions. The small scale FE analyses are typically carried out on models of up to a few meters length. The computational requirements of these methods limit their applications for only multi-scale structural analysis based on a sequential approach. For nested multi-scale approaches (i.e. the so called FE2 method) and for multi-scale multi-physic analyses, e.g. fluid structure interaction modeling of flexible risers, more efficient methods are required. The emphasis of the present work is on a highly efficient small-scale modelling method for flexible risers. By applying periodic boundary conditions, only a small fraction of a flexible pipe is used for detailed analysis. The computational model is firstly described. Then, the capability of the method in capturing the detailed nonlinear effects and the great advantage in terms of significant CPU time saving entailed by this method are demonstrated. For proof of concept the approach is applied on a simplified 3-layer pipe made of inner and outer polymer layers and an intermediate armour layer made of 40 steel tendons.


2021 ◽  
Author(s):  
Mareike Donaji Duffing Romero ◽  
Jordan K. Matley ◽  
Jiangang Luo ◽  
Jerald S. Ault ◽  
Simon J. Pittman ◽  
...  

Abstract Background Atlantic tarpon (Megalops atlanticus) are a highly migratory species ranging along continental and insular coastlines of the Atlantic Ocean. Due to their importance to regional recreational and sport fisheries, research has been focused on large-scale movement patterns of reproductively active adults in areas where they are of high economic value. As a consequence, geographically restricted focus on adults has left significant gaps in our understanding of tarpon biology and their movements, especially for juveniles in remote locations where they are common. Our study focused on small-scale patterns of movement and habitat use of juvenile and subadult tarpon using acoustic telemetry in a small bay in St. Thomas, U. S. Virgin Islands. Results Four juvenile tarpon (80 – 95 cm FL) were tracked from September 2015 to February 2018, while an additional eight juveniles (61 – 94 cm FL) left the study area shortly after tagging and were not included in analysis. The four resident tarpon had >78% residency and average activity space of 0.76 km2 (range = 0.08-1.17 km2) within Brewers Bay (1.8km2). Their vertical distribution was <18 m depth with occasional movements to deeper water. Activity was greater during day compared to night, with peaks during crepuscular periods. During the day tarpon used different parts of the bay with consistent overlap around the St. Thomas airport runway and at night tarpon typically remained in a small shallow lagoon. However, when temperatures in the lagoon exceeded 30 °C, tarpon moved to cooler, deeper waters outside the lagoon. Conclusion Our results, although limited to only four resident fish, provides new baseline data on the movement ecology of juvenile Atlantic tarpon. We showed that juvenile tarpon had high residency within a small bay and relatively stable non-overlapping daytime home ranges, except when seasonally abundant food sources were present. Fine-scale acoustic tracking for over a year showed the effects of extreme environmental conditions on tarpon movement and habitat use. These observations highlight the need for more extensive studies of juvenile and subadult tarpon across a broader range of their distribution, and compare the similarities and differences in behavior among various size classes of individuals from small juveniles to reproductively mature adults.


2018 ◽  
Vol 12 (3) ◽  
pp. 297-307 ◽  
Author(s):  
Takashi Tanizaki ◽  
Hideki Katagiri ◽  
António Oliveira Nzinga René ◽  
◽  

This paper proposes scheduling algorithms using metaheuristics for production processes in which cranes can interfere with each other. There are many production processes that involve cranes in manufacturing industry, such as in the steel industry, so a general purpose algorithm for this problem can be of practical use. The scheduling problem for this process is very complicated and difficult to solve because the cranes must avoid interfering with each other plus each machine has its own operational constraints. Although several algorithms have been proposed for a specific problem or small-scale problem, general purpose algorithms that can be solved in real time (about 30 minutes or less) in the company’s production planning work have not been developed for large-scale problems. This paper develops some metaheuristic algorithms to obtain suboptimal solutions in a short time, and it confirms their effectiveness through computer experiments.


2015 ◽  
Vol 08 ◽  
pp. 1-25 ◽  
Author(s):  
Robert W. Garnett ◽  
Richard L. Sheffield

An overview of the application of accelerators and accelerator technology in energy is presented. Applications span a broad range of cost, size, and complexity and include large-scale systems requiring high-power or high-energy accelerators to drive subcritical reactors for energy production or waste transmutation, as well as small-scale industrial systems used to improve oil and gas exploration and production. The enabling accelerator technologies will also be reviewed and future directions discussed.


2021 ◽  
Vol 9 (1) ◽  
Author(s):  
James Soland ◽  
Megan Kuhfeld ◽  
Joseph Rios

AbstractLow examinee effort is a major threat to valid uses of many test scores. Fortunately, several methods have been developed to detect noneffortful item responses, most of which use response times. To accurately identify noneffortful responses, one must set response time thresholds separating those responses from effortful ones. While other studies have compared the efficacy of different threshold-setting methods, they typically do so using simulated or small-scale data. When large-scale data are used in such studies, they often are not from a computer-adaptive test (CAT), use only a handful of items, or do not comprehensively examine different threshold-setting methods. In this study, we use reading test scores from over 728,923 3rd–8th-grade students in 2056 schools across the United States taking a CAT consisting of nearly 12,000 items to compare threshold-setting methods. In so doing, we help provide guidance to developers and administrators of large-scale assessments on the tradeoffs involved in using a given method to identify noneffortful responses.


Author(s):  
Gunay Vagifgiz

Oil and gas deposits differ depending on the bed size, geological-physical development conditions, oil quality and geographic location. Including them in the development is connected with various investments to the main constructions; subsistence and current material expenses also differ. Therefore, from the point of view of economic efficiency, oil and gas deposits are not equal. Location of oil and industry leads to the problem of the sequence of putting of various deposits into operation and their development rate. The sizes of oil and gas beds and available oil and gas reserves in them give reason to say which of these beds will be put into operation in the near future. Completion and development of large scale deposits require less investments compared to small scale deposits. Such deposits are usually highly productive, expenses per a production unit in them is small. All these determined importance of the use of reserves in large scale deposits in the first turn.


Author(s):  
J. Schupp ◽  
B. W. Byrne ◽  
N. Eacott ◽  
C. M. Martin ◽  
J. Oliphant ◽  
...  

Small diameter pipelines are routinely used to transport oil and gas between offshore production plants and the mainland, or between remote subsea well-heads and a centralised production facility. The pipelines may be placed on the soil surface but it is more usual that they are placed into trenches, which are subsequently backfilled. For the buried pipelines a well established problem has been that of upheaval buckling. This occurs because the fluid is usually pumped through the pipes at elevated temperatures causing the pipeline to experience thermal expansion which, if restrained, leads to an increase in the axial stress in the pipeline possibly resulting in a buckling failure. A secondary phenomenon that has also been identified, particularly in loose silty sands and silts, involves floatation of pipelines through the backfill material, usually shortly after burial. At the University of Oxford a project sponsored by EPSRC and Technip Offshore UK Ltd has commenced to investigate in detail the buckling and floatation problems. The main aim of the research programme is to investigate three-dimensional effects on the buckling behaviour. The initial experiments involve the more typical plane strain pipeline unburial tests to explore the relationship between depth of cover, uplift rate, pipeline diameter and pullout resistance under drained and undrained conditions. The second and main phase of experiments involves inducing a buckle in a model pipeline under laboratory conditions and making observations of the pipe/soil response. This paper will describe the initial findings from the research including a) plane strain pipe unburial tests in loose dry sand, and, b) initial small scale three-dimensional buckling tests. The paper will then describe the proposed large scale three-dimensional testing programme that will be taking place during 2006 and 2007.


1994 ◽  
Vol 3 (4) ◽  
pp. 288-308 ◽  
Author(s):  
David N. Snowdon ◽  
Adrian J. West

VR is already evolving away from single user small-scale demonstrators, and inexorably toward sophisticated environments in which many geographically distributed users can perform a diverse range of activities. There will therefore be a pressure to make such environments increasingly general purpose and dynamic in their support of applications, paralleling perhaps the historical evolution of conventional operating systems. It is from speculations about the nature of such a future large-scale VR system that the AVIARY project has developed. AVIARY provides multiple worlds, each with its own set of laws, that may be tailored to suit particular application domains. The overall structure enables a coherent relationship between worlds to be maintained, which is important both for purposes of code reuse, and to aid users in navigating the system. A prototype implementation exists that addresses underlying implementation issues in the AVIARY model, and, in particular, distribution across heterogeneous processor networks, dynamic management of objects and message types within the system, the separation of graphics processing, and the management of spatial extent. Implementations of the prototype have been tested on a Transputer array, and a heterogeneous network of Sun and Silicon Graphics workstations. The system is currently being ported to a 2.4-Gflop KSR-1 parallel supercomputer. This paper reviews approaches to distributed, multi-application VR systems, presents pertinent elements of the AVIARY design, and describes the prototype implementation with particular attention given to the issues of distribution.


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