2,849 research outputs found
Generating large scale images using GANs
Generative Adversarial Networks have been used for the task of image generation and has achieved impressive results. There is always a challenge to train networks that generate large scale images since they tend to be huge and training needs a lot of data. In this work, we tackle this problem by dividing it into two smaller parts. We first generate small scale images using GANs then use a super resolution network to enlarge the generated images resulting in large scale images. Using a super resolution network helps in adding more details to the image which results in a better quality image. This technique has been tested with a small amount of data and obtained better inception scores over the baseline GAN
A Comparison of SOR, ADI and Multigrid Methods for Solving Partial Differential Equations
This article presents several numerical techniques for solving Laplace
equation. A numerical FORTRAN solver is developed to solve the 2D laplace
equation. The numerical approaches implemented in the solver include Jacobi,
Gauss-Siedel, Successive Over Relaxation, Alternating Direct Implicit and
Multigrid methods. Detailed comparison between different numerical methods is
presented and discusse
Work force assignment and planning for onshore oil and gas wells cementing operations
In oil and gas well cementing operations, workers are exposed to long consecutive hours of work and irregular off times due to the nature of such service and inefficient workforce assignment. Overloading human resources increases the potential of errors during service execution, which is mostly considered catastrophic in this field of services. Efficiency of human resources overall reduces as they become over utilized. Finally, loyalty of employees to the company becomes unstable.
The objective of this project is to develop a more efficient workforce assignment policy for oil and gas well cementing operations. Cementing operation is critical and vital in a life cycle of any oil or gas well. Operating companies consider this operation as one of the most critical operations during the construction of a well and they explicitly place a zero margin of error in this operation.
A case study from the land field of Dukhan is examined in this project. An international oil field services provider is the current service provider for cementing services. The main deficiency of the existing planning policy is the overloading of resources performing the service operation. The project ultimately aims to reduce the average positive deviation from the maximum shift duration for each member of the service team. A sub-objective of the project is limit the maximum waiting time a drilling rig spend waiting on crew members to execute the job to 24 hours.
Methodology of the project starts by studying the current personnel deployment policy and defining the problem. Following that, previous operational data is collected over the span of 1 year and probability distributions are determined for uncertain variables. Finally, the new proposed planning policy is simulated in AnyLogic Multimethod Simulation software to examine its efficiency, where generated data is collected, analyzed and compared to the existing planning policy.
The combination of both the project methodology and the relevant literature review provide strong bases for developing alternative personnel assignment policies. Methodology in general is considered a good foundation for staff assignment problems, while literature review gives insight for the possibility of improving current assignment policy in order to have a more balanced work load distribution.
Obtained results confirm superiority of proposed planning policy. Average positive deviation dropped considerably compared to the current assignment policy. Drilling rig waiting time remains below pre-set maximum waiting time. Thus, proposed policy enhanced personnel assignment without compromising the integrity of operations
Trading Wireless Information and Power Transfer: Relay Selection to Minimize the Outage Probability
This paper studies the outage probability minimization problem for a multiple
relay network with energy harvesting constraints. The relays are hybrid nodes
used for simultaneous wireless information and power transfer from the source
radio frequency (RF) signals. There is a trade-off associated with the amount
of time a relay node is used for energy and information transfer. Large
intervals of information transfer implies little time for energy harvesting
from RF signals and thus, high probability of outage events. We propose relay
selection schemes for a cooperative system with a fixed number of RF powered
relays. We address both causal and non-causal channel state information cases
at the relay--destination link and evaluate the trade-off associated with
information/power transfer in the context of minimization of outage
probability.Comment: IEEE GlobalSiP, 201
The failure of vernacular housing policy and design in Egypt, the case of Nubia
In the developing countries, it has been argued that most vernacular settlements are unsatisfactory for many reasons, one of them is the way in which the culture of the people is disregarded. Therefore, it is the objective of this research to find a relevant social scientific approach to the design of houses in these areas, with special reference to the Nubian settlement in Egypt. This study attempts to delineate the development of cultural influences on housing needs which affect the life of the Nubian people. A general view of the various problems in the developing countries that have affected house design is outlined. This is discussed in connection with the problems of contemporary vernacular houses in Egypt in order to reveal the reasons and causes that led to the establishment of new settlement in particular. Some steps towards identifying significant morphological factors in an Egyptian Nubian community are examined and the empirical task has been to establish why the Government house design falls short of the needs of the Nubian settlers. The case of the village of Kom-Ombo is examined as an example and comparison of the four case studies groups that were found there was used to help analyse the satisfaction results. In doing so, a field study was undertaken to compare Government with self-built houses that have been built in the present site and homeland. The field study was accomplished using interviews to explore and investigate the Nubians' socio-economical and psychological needs that consequently led them to abandon their Government houses and build more satisfactory ones back in the homeland. The conclusions drawn from these studies could be used to recommend a design approach to Government architects based on the concept of how the people settle down to help build their own houses collaboratively. This, however, is not intended to be an ultimate solution but merely an example of the results that could be attained using a methodological objective. The above approach is to emphasise rather than achieve conceptual (alternative) optimum solutions, since every project must develop its own solutions according to its own needs.In the developing countries, it has been argued that most vernacular settlements are unsatisfactory for many reasons, one of them is the way in which the culture of the people is disregarded. Therefore, it is the objective of this research to find a relevant social scientific approach to the design of houses in these areas, with special reference to the Nubian settlement in Egypt. This study attempts to delineate the development of cultural influences on housing needs which affect the life of the Nubian people. A general view of the various problems in the developing countries that have affected house design is outlined. This is discussed in connection with the problems of contemporary vernacular houses in Egypt in order to reveal the reasons and causes that led to the establishment of new settlement in particular. Some steps towards identifying significant morphological factors in an Egyptian Nubian community are examined and the empirical task has been to establish why the Government house design falls short of the needs of the Nubian settlers. The case of the village of Kom-Ombo is examined as an example and comparison of the four case studies groups that were found there was used to help analyse the satisfaction results. In doing so, a field study was undertaken to compare Government with self-built houses that have been built in the present site and homeland. The field study was accomplished using interviews to explore and investigate the Nubians' socio-economical and psychological needs that consequently led them to abandon their Government houses and build more satisfactory ones back in the homeland. The conclusions drawn from these studies could be used to recommend a design approach to Government architects based on the concept of how the people settle down to help build their own houses collaboratively. This, however, is not intended to be an ultimate solution but merely an example of the results that could be attained using a methodological objective. The above approach is to emphasise rather than achieve conceptual (alternative) optimum solutions, since every project must develop its own solutions according to its own needs
Load Balancing Hotspots in Sensor Storage Systems
Sensor networks provide us with the means of effectively monitoring and interacting with the physical world. A sensor network usually consists of a large number of small inexpensive battery-operated sensors deployed in a geographic area. This dissertation considers a sensor network deployed to monitor a disaster area. First responders continuously issue ad-hoc queries while moving in the disaster area. In such an environment, it is often more beneficial to store sensor readings and process ad-hoc queries within rather than outside the sensor network.Recently, this led to an increased popularity of Data-Centric Storage (DCS).A DCS scheme is based on a mapping function from readings to sensors based on the attribute values of each reading. This mapping function defines the DCS index structure.Two significant problems arising in this DCS network model due to data and traffic skewness are storage hotspots and query hotspots. Storage hotspots are formed when many sensor readings are mapped for storage to a relatively small number of sensor nodes. Query hotspots occur when many user queries target few sensor nodes. Both types of hotspots are hard to predict. Storage hotspots result in an uncontrolled reading shedding that decreases the Quality of Data (QoD). Due to the limited wireless bandwidth of sensors, hotspots decrease QoD by increasing collisions (thus losses) of reading/query packets. When lasting long enough, hotspots affect the Quality of Service (QoS) by unevenly depleting energy in the sensor network.This dissertation addresses both problems of hotspots through load balancing. The main dissertation hypothesis is that data migration resulting from local or global load balancing of the DCS index structure can effectively solve the hotspot problems. The contributions of this dissertation lie in developing two schemes, namely, the Zone Sharing/Zone Partitioning/Zone Partial Replication (ZS/ZP/ZPR) scheme and the K-D tree based Data-Centric Storage (KDDCS) scheme. ZS/ZP/ZPR detects and decomposes both types of hotspots through load balancing in the hotspot area. KDDCS avoids the formation of hotspots through globally load-balancing the underlying DCS index structure. Experimental evaluation shows the effectiveness of the proposed schemes in coping with hotspots in comparison to the state-of-the-art DCS schemes
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