Improvement of volumetric sweep efficiency during oil production using ECO-clay

Excess water production during oil production is a big challenge that may affect the economics and environmental concerns. Different methods have been developed to reduce water production and improve the efficiency of oil recovery. One promising approach is using a nanocomposite that creates a gel for plugging fractures in the reservoir. This system can potentially improve volumetric sweep efficiency during oil production by decreasing water permeability and creating a better path for the oil to flow to the well. This study investigates the potential of an ECO-clay system comprising Laponite and Hydrolyzed Polyacrylamide (HPAM) as a water conformance technique in fractured reservoirs. The investigation involves bulk experiments to screen different concentrations of clay and polymer, while also evaluating the effects of various ions and additives on gel performance. Promising systems are subsequently subjected to filtration tests to assess their suitability for gel placement into fractures. Ultimately, the goal was to identify the most effective gel system and conduct core flooding tests to evaluate its potential for plugging fractures and improving oil recovery. Among the systems tested, two were selected for dynamic experiments: A Laponite S482-CaCl2 system and a nanocomposite system with HPAM addition. Both showed good results in the filtrations and floods, achieving a water permeability reduction of 19.6 and 5.3 times lower than the pre-treatment permeability respectively. Finally, the Laponite S482-CaCl2 system represented the most promising gel system for fracture plugging in chalk, because its higher permeability reduction. These findings highlight the potential of the identified gel system for effectively addressing water production issues in fractured chalk reservoirs, thereby improving oil recovery efficiency, reducing water production and CO2 emission. To improve the understanding and implementation of these gel systems, further work is required in a more in-depth gel structure tests, long-term stability and performance evaluation, compatibility with other reservoir fluid study, and finally field-scale experiments and simulations. Addressing these issues will help create a reliable and cost-effective fractured reservoir water conformance technique

Comparative study of lactation curves and milk quality in Holstein versus Swedish Red and White-Holstein Cross Cows

The objective of this study reported in this research paper was to compare the lactation curves of the production of milk, fat, protein, percentages of fat and protein, and somatic cell score in purebred Holstein (H) cows and Swedish Red and White (SRW) - Holstein (SxH) crossbred cows in the south-central region of the province of Cordoba, Argentina. The data set consisted of 32847 herd-test records from 1244 purebred H cows and 310 SRW x H crossbred cows, from three commercial dairy farms with cows of first to fifth or more lactations. The curves were modeled using the fourth-order Legendre orthogonal polynomials. In this study, the data of production of milk, fat production, protein production, percentage of fat, percentage of protein and somatic cell score (SCS) were analyzed. Purebred H cows had significantly higher milk production, more fat production and higher protein production levels than did SxH crossbred cows. However, SxH crossbred cows produced milk that had a higher percentage of fat and a higher percentage protein than did purebred H cows. In none of the lactations did somatic cell score differ significantly between the two breed groups. The results of our study showed that, SxH crossbred cows had significantly higher percentages of fat and protein; however, purebred H cows were significantly superior to SxH crossbred cows for the production of 305-d milk, fat, and protein. Mammary health, expressed in SCS, did not differ significantly between the two breed groups. Thus, suggest that crossbreeding Holstein purebred cows with SRW bulls can improve the composition of milk solids without affecting mammary health and, in this way, compensate substantially for any potential loss in the production and/or quality of the milk of the crossbred cows compared to H purebred cows.Fil: Pipino, Diego. Agroveterinaria Pipino; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; ArgentinaFil: Piccardi, Mónica Belén. Universidad Nacional de Córdoba. Facultad de Ciencias Agropecuarias. Departamento de Desarrollo Rural. Area de Estadística y Biometría; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lembeye, Felipe. Soprole. Gerencia de Abastecimiento. Departamento Agropecuario; ChileFil: Lopez Villalobos, Nicolas. Massey University; Nueva ZelandaFil: Vazquez, Maria Isabel. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Shallow versus Deep Integration between Mediterranean Countries and the EU and within the Mediterranean Region

The paper aims at assessing the specific impact of shallow versus deep integration between Mediterranean (MED) countries1 and their partners in the European Union (EU) as well as between the MED countries themselves. It relies on dataset developed for this project concerning tariffs (as a proxy for shallow integration) and Non Tariff Measures (NTMs)2 (as a proxy for deep integration). Additional data are also included in order to take into account other trade costs, especially transport costs and logistics costs. In this regard, an original dataset of maritime freight cost (Maersk, 2007) is introduced as well as the trade logistics performance (TLP) index produced by the World Bank. Such datasets are useful for providing additional insight into deep integration. The paper starts by calculating the magnitude of NTMs in terms of ad valorem tariff equivalent (AVEs). The estimation of NTMs through ad valorem equivalents (AVEs) shows that Algeria and Jordan have the highest value of AVEs, whereas Tunisia, Morocco, and Egypt have the lowest value. A gravity model is then estimated with special emphasis on trade costs which are the crucial point in our research study. Given the limitation of data on NTMs, the gravity model is estimated for only one year (2001), and for each MED country. Trade costs are represented by tariffs, AVEs of NTMs, and transport and logistics costs. The idea is to test which of the three elements of trade costs are the most impeding to bilateral trade between MED countries and EU countries as well as amongst MED countries. The model shows that tariffs, NTMs, and trade and logistics costs have a significant impact on trade, but is highly vivid in countries suffering from high tariff rates, prevalence of NTMs, and trade costs. A number of simulations are carried out trying to differentiate between the impact of partial liberalization and full liberalization on trade creation. The results obtained show that full liberalization has a significant effect whether it is only related to shallow integration (tariff removal) or deep integration (NTMs and trade and logistics). The effect is higher if trade costs and logistics are improved. The results are far less if only partial liberalization takes place and in several countries is insignificant implying that marginal reductions in NTMs or tariffs cannot always help to create trade. Finally the study shows that there is a huge potential for enhancing trade amongst MED countries if trade costs are lowered, logistics is improved, and NTMs are abolished.Regional Trade Agreements, Regional Integration, Non-Tariff-Measures, Deep versus shallow integration, South Mediterranean countries, European Union Trade Agreements

Sibling Worlds

David Nicolas Lopez Moncayo was awarded Honorable Mention for his essay

On the Incidence of C IV Absorbers Along the Sightlines to Gamma-Ray Bursts

We report on the statistics of strong (W_r > 0.15 A) C IV absorbers at z=1.5-3.5 toward high-redshift gamma-ray bursts (GRBs). In contrast with a recent survey for strong Mg II absorption systems at z < 2, we find that the number of C IV absorbers per unit redshift dN/dz does not show a significant deviation from previous surveys using quasi-stellar objects (QSOs) as background sources. We find that the number density of C IV toward GRBs is dN/dz(z~1.5)= 2.2 +2.8/-1.4, dN/dz(z~2.5)= 2.3 +1.8/-1.1 and dN/dz(z~3.5)= 1.1 +2.6/-0.9. These numbers are consistent with previous C IV surveys using QSO spectra. Binning the entire dataset, we set a 95% c.l. upper limit to the excess of C IV absorbers along GRB sightlines at twice the incidence observed along QSO sightlines. Furthermore, the distribution of equivalent widths of the GRB and QSO samples are consistent with being drawn from the same parent population. Although the results for Mg II and C IV absorbers along GRB sightlines appear to contradict one another, we note that the surveys are nearly disjoint: the C IV survey corresponds to higher redshift and more highly ionized gas than the Mg II survey. Nevertheless, analysis on larger statistical samples may constrain properties of the galaxies hosting these metals (e.g. mass, dust content) and/or the coherence-length of the gas giving rise to the metal-line absorption.Comment: Accepted version (for publication in ApJ), results unchanged, 18 pages, 3 tables, 5 figure

Mobile travel services: A three-country study into the impact of local circumstances

In this paper we explore the difference in acceptance patterns of mobile services that are related to travelling in three countries: Finland, The Netherlands and New Zealand. The objective of this paper is to understand differences in the use of Mobile Travel Services in three countries that differ with regard to national travel patterns. This paper also contributes to the discussion of the relevance of the Technology Acceptance Model for mobile applications by focusing on the importance of context characteristics, such as the degree of mobility of the user, the social situation people are in, and their need for social interaction. Based on surveys in the three countries as executed in 2009, we use structural equation modelling to find differences in patterns. The paper concludes that context factors have an impact on the relation between the core concepts as used in TAM and DOI approach, and that t here is a clear need for closer research in the moderating effect of physical (e.g. mobile and fixed context) and social context, as well as the need for social interaction. Moreover it is clear that country specific characteristics play a role in the acceptance of mobile travel services. As we pointed out in many of our research projects before the acceptance and use of mobile services requires deep understanding from individual, context and technology related characteristics and their mutual interactions

RGB-D Tracking and Optimal Perception of Deformable Objects

Addressing the perception problem of texture-less objects that undergo large deformations and movements, this article presents a novel RGB-D learning-free deformable object tracker in combination with a camera position optimisation system for optimal deformable object perception. The approach is based on the discretisation of the object''s visible area through the generation of a supervoxel graph that allows weighting new supervoxel candidates between object states over time. Once a deformation state of the object is determined, supervoxels of its associated graph serve as input for the camera position optimisation problem. Satisfactory results have been obtained in real time with a variety of objects that present different deformation characteristics