scholarly journals The model to predict sand production for production wells at Cuu Long basin

2014 ◽  
Vol 17 (3) ◽  
pp. 172-178
Author(s):  
Dung Quoc Ta ◽  
Tung Thanh Hoang
Keyword(s):  
Failure Analysis ◽  
Complex Problem ◽  
Urgent Problem ◽  
Sand Production ◽  
Surface Formation ◽  
Advantages And Disadvantages ◽  
Production Wells ◽  
Long Time ◽  
Sandstone Reservoirs

Sand production in Sandstone reservoirs is a complex problem to Oil & Gas companies. Many methods have used to solve this problem but these methods only have effect for the first period of production without effective in long time. Sand production causes big damages such as: producing tools corrosion in hole, separating tools corrosion at surface, formation collapse, so sand production in well is always the urgent problem. Based on formation characteristic research, advantages and disadvantages of sand failure analysis and combining the advanced methods, this study introduces Production Sand Pressure Model to predict sand productivity in sedimentary reservoirs in field X in Cuu Long basin.

New Rapid Failure Analysis Techniques for Multilevel Metallization

MRS Bulletin ◽  
1995 ◽  
Vol 20 (11) ◽  
pp. 74-77
Author(s):  
Edward I. Cole ◽  
Richard E. Anderson
Keyword(s):  
Integrated Circuits ◽  
Product Development ◽  
Failure Analysis ◽  
New Product Development ◽  
New Product ◽  
Electronics Industry ◽  
New Techniques ◽  
Analysis Techniques ◽  
Advantages And Disadvantages ◽  
Failure Site

Open interconnections on integrated circuits (ICs) are a serious and ubiquitous problem throughout the micro-electronics industry. The efforts to understand the mechanisms responsible for producing open interconnections and to develop analytical methods to localize them demonstrate the concern manufacturers have for this problem. Multiple layers of metallization not only increase the probability that an open conductor or via will occur because of the increased number of interconnections and vias but also increase the difficulty in localizing the site of the failure because upper layers may mask the failure site.Rapid failure analysis of open-conductor defects is critical in new product development and reliability assessment of ICs where manufacturing and product development delays can cost millions of dollars a day. In this article, we briefly review some standard failure analysis approaches and then concentrate on new techniques to rapidly locate open-conductor defects that would have been difficult or impossible to identify using earlier methods. Each method is described in terms of the physics of signal generation, application, and advantages and disadvantages when compared to existing methods.

Review on critical technology development of avian radar system

2022 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Weishi Chen ◽  
Yifeng Huang ◽  
Xianfeng Lu ◽  
Jie Zhang
Keyword(s):  
Technology Development ◽  
Time Integration ◽  
Radar System ◽  
Content Type ◽  
Advantages And Disadvantages ◽  
Detection And Tracking ◽  
Critical Technology ◽  
Long Time ◽  
Long Time Integration ◽  
Target Characteristics

Purpose This paper aims to review the critical technology development of avian radar system at airports. Design/methodology/approach After the origin of avian radar technology is discussed, the target characteristics of flying birds are analyzed, including the target echo amplitude, flight speed, flight height, trajectory and micro-Doppler. Four typical airport avian radar systems of Merlin, Accipiter, Robin and CAST are introduced. The performance of different modules such as antenna, target detection and tracking, target recognition and classification, analysis of bird information together determines the detection ability of avian radar. The performances and key technologies of the ubiquitous avian radar are summarized and compared with other systems, and their applications, deployment modes, as well as their advantages and disadvantages are introduced and analyzed. Findings The ubiquitous avian radar achieves the long-time integration of target echoes, which greatly improves detection and classification ability of the targets of birds or drones, even under strong background clutter at airport. In addition, based on the big data of bird situation accumulated by avian radar, the rules of bird activity around the airport can be mined to guide the bird avoidance work. Originality/value This paper presented a novel avian radar system based on ubiquitous digital radar technology. The authors’ experience has confirmed that this system can be effective for airport bird strike prevention and management. In the future, the avian radar system will see continued improvement in both software and hardware, as the system is designed to be easily extensible.

Coupling Secondary Ion Mass Spectrometry and Atom Probe Tomography for Atomic Diffusion and Segregation Measurements

2019 ◽  
Vol 25 (2) ◽  
pp. 517-523
Author(s):  
Alain Portavoce ◽  
Khalid Hoummada ◽  
Lee Chow
Keyword(s):  
Mass Spectrometry ◽  
Atom Probe Tomography ◽  
Secondary Ion Mass Spectrometry ◽  
Depth Resolution ◽  
Atom Probe ◽  
Atomic Diffusion ◽  
Advantages And Disadvantages ◽  
Ion Mass Spectrometry ◽  
Long Time ◽  
Secondary Ion

AbstractFor a long time, secondary ion mass spectrometry (SIMS) was the only technique allowing impurity concentrations below 1 at% to be precisely measured in a sample with a depth resolution of few nanometers. For example, SIMS is the classical technique used in microelectronics to study dopant distribution in semiconductors and became, after radiotracers were forsaken, the principal tool used for atomic transport characterization (diffusion coefficient measurements). Due to the lack of other equivalent techniques, sometimes SIMS could be used erroneously, especially when the analyzed solute atoms formed clusters, or for interfacial concentration measurements (segregation coefficient measurements) for example. Today, concentration profiles measured by atom probe tomography (APT) can be compared to SIMS profiles and allow the accuracy of SIMS measurements to be better evaluated. However, APT measurements can also carry artifacts and limitations that can be investigated by SIMS. After a summary of SIMS and APT measurement advantages and disadvantages, the complementarity of these two techniques is discussed, particularly in the case of experiments aiming to measure diffusion and segregation coefficients.

scholarly journals Application of Type-1 and Type-2 Fuzzy Logic Controller for The Real Swarm Robot

2019 ◽  
Vol 15 (06) ◽  
pp. 83 ◽  
Author(s):  
Ade Silvia Handayani ◽  
Nyayu Latifah Husni ◽  
Siti Nurmaini ◽  
Irsyadi Yani
Keyword(s):  
Fuzzy Logic ◽  
Fuzzy Logic Controller ◽  
Complex Problem ◽  
The Real ◽  
Advantages And Disadvantages ◽  
Path Navigation ◽  
Swarm Robot ◽  
Interval Type

Navigation is one of the typical problem domains occurred in studying swarm robot. This task needs a special ability in avoiding obstacles.  This research presents the navigation techniques using type 1 fuzzy logic and interval type 2 fuzzy logic. A comparison of those two fuzzy logic performances in controlling swarm robot as tools for complex problem modeling, especially for path navigation is presented in this paper.  Each hierarchical of fuzzy logic shows its advantages and disadvantages.  For testing the robustness of type-1 fuzzy logic and interval type-2 fuzzy logic algorithms, 3 robots for the real swarm robot experiment are used.  Each is equipped with one compass sensor, three distance sensors, and one X-Bee communication module.  The experimental results show that type-2 fuzzy logic has better performance than type-1 fuzzy logic.

scholarly journals Pressure ulcers: Current understanding and newer modalities of treatment

2015 ◽  
Vol 48 (01) ◽  
pp. 004-016 ◽  
Author(s):  
Surajit Bhattacharya ◽  
R. K. Mishra
Keyword(s):  
Pressure Ulcers ◽  
Treatment Options ◽  
Healing Process ◽  
Treatment Algorithm ◽  
Wound Debridement ◽  
Advantages And Disadvantages ◽  
Prone Area ◽  
Long Time

ABSTRACTThis article reviews the mechanism, symptoms, causes, severity, diagnosis, prevention and present recommendations for surgical as well as non-surgical management of pressure ulcers. Particular focus has been placed on the current understandings and the newer modalities for the treatment of pressure ulcers. The paper also covers the role of nutrition and pressure-release devices such as cushions and mattresses as a part of the treatment algorithm for preventing and quick healing process of these wounds. Pressure ulcers develop primarily from pressure and shear; are progressive in nature and most frequently found in bedridden, chair bound or immobile people. They often develop in people who have been hospitalised for a long time generally for a different problem and increase the overall time as well as cost of hospitalisation that have detrimental effects on patient’s quality of life. Loss of sensation compounds the problem manifold, and failure of reactive hyperaemia cycle of the pressure prone area remains the most important aetiopathology. Pressure ulcers are largely preventable in nature, and their management depends on their severity. The available literature about severity of pressure ulcers, their classification and medical care protocols have been described in this paper. The present treatment options include various approaches of cleaning the wound, debridement, optimised dressings, role of antibiotics and reconstructive surgery. The newer treatment options such as negative pressure wound therapy, hyperbaric oxygen therapy, cell therapy have been discussed, and the advantages and disadvantages of current and newer methods have also been described.

scholarly journals Aflatoxin species: their health effects and determination methods in different foodstuffs

2012 ◽  
Vol 10 (3) ◽  
pp. 675-685 ◽  
Author(s):  
Sezgin Bakırdere ◽  
Selin Bora ◽  
E. Bakırdere ◽  
Fırat Aydın ◽  
Yasin Arslan ◽  
...  
Keyword(s):  
Health Effects ◽  
Analytical Techniques ◽  
The Other ◽  
Advantages And Disadvantages ◽  
Time Period ◽  
Long Time ◽  
Sensitive Determination ◽  
Determination Methods ◽  
And Storage

AbstractCarcinogenic and mutagenic properties of aflatoxin species are known in literature. Their intake over a long time period might be health-dangerous for human even at trace levels. It is well known that different foodstuffs can be contaminated by aflatoxin species through growing and storage. Due to the serious health effects, sensitive determination of aflatoxin species in any matrices related with the human being is very crucial at trace levels. In literature, there are sensitive techniques to analyze the different samples for the contents of their aflatoxin species. Each technique has some advantages and disadvantages over the other techniques. This review aims to summarize the different health effects of aflatoxin species, development of analytical techniques and applications of developed techniques in a variety of matrices.

Failure Criteria and its Application in Wellbore Studies

2016 ◽  
Vol 1133 ◽  
pp. 624-628
Author(s):  
Sonny Irawan ◽  
Mahmood Bataee ◽  
Mohammad Reza Zare
Keyword(s):  
Oil And Gas ◽  
Failure Criteria ◽  
Rock Surface ◽  
Sand Production ◽  
Injection Wells ◽  
Surface Failure ◽  
Production Wells ◽  
Oil Flow ◽  
The Stability ◽  
Wellbore Failure

This paper has reviewed the failure criteria that had been applied in the wellbore studies. Rock failure studies had applied in the wellbore and reservoir to establish the stability, which is a major problem in oil and gas wells. There problems are both in injection wells and production wells. In injection wells, fracturing is a problem and in production wells, sand production affects the oil flow rate. The stress state of the well determines the stability of the well using the failure criteria.Different failure criteria and their applications had been studied. The theory of the failure has expressed; then applied criteria, formulation and modification of different criteria is expressed for different wellbore studies. And finally the important aspects and differences in wellbore failure rather than the rock surface failure has been discussed.

Elementary excitation and energy landscape in simple liquids

2014 ◽  
Vol 28 (14) ◽  
pp. 1430006 ◽  
Author(s):  
T. Egami
Keyword(s):  
Energy Landscape ◽  
Complex Problem ◽  
Elementary Excitation ◽  
Single Atom ◽  
Topological Excitations ◽  
Atomic Transport ◽  
Potential Energy Landscape ◽  
Metallic Liquids ◽  
Long Time ◽  
Complex Phenomena

The nature of excitations in liquids has been a subject of debate for a long time. In liquids, phonons are extremely short-lived and marginalized. Instead, recent research results indicate that local topological or configurational excitations (anankeons) are the elementary excitations in high temperature metallic liquids. Local topological excitations are those which locally alter the atomic connectivity network by cutting or forming atomic bonds, and are directly tied to the atomistic origin of viscosity in the liquid. The local potential energy landscape (PEL) of anankeons represents the probability weighted projection of the global PEL to a single atom. The original PEL is an insightful concept, but is highly multi-dimensional and difficult to characterize or even to visualize. A description in terms of the local PEL for anankeons appears to offer a simpler and more effective approach toward this complex problem. At the base of these advances, is the recognition that atomic discreteness and the topology of atomic connectivity are the most crucial features of the structure in liquids, which current nonlinear continuum theories cannot fully capture. These discoveries could open the way to the explanation of various complex phenomena in liquids, such as atomic transport, fragility, and the glass transition, in terms of these excitations.

Acidizing Sandstone Reservoirs With Aluminum-Based Retarded Mud Acid

SPE Journal ◽  
2016 ◽  
Vol 21 (03) ◽  
pp. 1050-1060 ◽  
Author(s):  
Qin Ji ◽  
Lijun Zhou ◽  
Hisham Nasr-El-Din
Keyword(s):  
Clay Minerals ◽  
Inductively Coupled Plasma ◽  
Systematic Investigation ◽  
19F Nmr ◽  
Reaction Products ◽  
Inductively Coupled ◽  
Permeability Enhancement ◽  
Reservoir Permeability ◽  
Long Time ◽  
Sandstone Reservoirs

Summary Aluminum chloride (AlCl3) has been used as a retarding agent for mud acid for a long time; its applications are studied in the laboratory and tested in the field. The theory and mechanism of AlCl3 retardation were investigated in many works involving mud acidizing and reservoir-permeability enhancement. This paper furthers this investigation with solubility tests, coreflood tests, and 19F nuclear magnetic resonance (NMR) to better understand the mechanism of AlCl3 working as a retarding agent in mud acid. The reactivity of Al-based retarded mud acid (15 wt% HCl, 1.5 wt% HF, and 5 wt% AlCl3·6H2O) with clay minerals and sandstones at different conditions has not been examined fully. To enhance the acid performance and to minimize formation damage, a systematic investigation of the interactions between the Al-based retarded mud acid and clay minerals in sandstone reservoirs is provided in this study. Furthermore, for the first time, 19F NMR spectroscopy was used to follow the reactions of Al-based retarded mud acid with clay minerals. Solubility tests were performed to evaluate the retardation of the Al-based retarded mud acid when reacted with kaolinite, bentonite, and illite. Inductively coupled plasma (ICP) and 19F NMR were used to analyze the concentrations of key cations and components in the supernatant, whereas the scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) techniques were used to identify the reaction products and to explore the possibility of the presence of any precipitation. Coreflood tests of sandstone cores were also conducted. This study shows that AlCl3 can retard the reaction of hydrofluoric acid (HF) with kaolinite, bentonite, or illite at 75 and 200 °F in Al-based retarded mud acid. Even with 5 wt% AlCl3·6H2O added in the acid system, no AlF3 precipitate was observed in any of the solubility tests. 19F NMR results showed that AlF4− and AlF3 were the only Al-F species existing in the spent Al-based retarded mud acid. H2SiF6 and HSiF5 were also identified. Coreflood tests showed significant permeability improvement to Berea sandstone when Al-based retarded mud acid was used, and the enhancement diminished when the temperature increased to 300 °F. Computed-tomography (CT) scan showed deeper penetration of Al-based retarded mud acid than mud acid at 75 °F, and the penetration reduced when temperature increased to 200 °F. On the basis of these results, new mechanisms were developed to better understand the reaction of Al-based retarded mud acid and clay minerals.

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