bluuebunny/crossref_metadata_2025 huggingface dataset:
Fracture Conductivity Decrease Due to Proppant Deformation and Crushing, a Parametrical Study
Authors: Han Jiahang , Wang John Yilin
Published: October 2014

Sustainable high fracture conductivity is a key to successful stimulation. The reduction of hydraulic fracture conductivity due to proppant deformation and crushing is frequently observed. Previous researches are based on laboratory experiments and empirical correlations, which can not fully explain proppant damage in field cases. In this paper, we applied our fully coupled fluid flow and geomechanical model to further understand the proppant pack deformation and crushing.

Parametric studies on wellbore and reservoir pressures, formation properties, and proppant biot constant were performed to understand proppant deformation and crushing in different conditions. Additionally, an analytical model for avoiding proppant crushing was developed for fractured wells.

Through this research, we found fracture conductivity loss due to deformation and crushing are severer than laboratory results. Large deformation and high probability of crushing were observed near wellbore according to the net pressure. Fast flow back (low bottom hole pressure) would generate large proppant crushed zone. Various reservoir properties as pressure gradient, formation stiffness, and matrix permeability were also investigated. Strong proppant is highly recommended for natural fractures, and hydraulic fracture near well bore especially for tight formations. Small chock size (high BHP) is also recommended during early production. Additionally, a simple analytical model is provided, accoding to the parametrical studies, for operating well without breaking proppant pack.
Enhancement of Filtration Properties in Surfactant-Based and Polymeric Fluids by Nanoparticles
Authors: Fakoya M. F. , Shah S. N.
Published: October 2014

Currently, there are few available publications regarding the application of nanotechnology in fluid loss control; hence, this technology needs more exploration. During hydraulic fracturing, fracture conductivity damage and other problems associated with excessive leak-off rate can be significantly curtailed by utilizing nano-fluid systems that evolve from further research studies.

An experimental study is presented on the application of nanotechnology on filtration properties of surfactant-based fluids (SBF), polymeric fluids, and SBF-polymeric fluid blends. The concentration of SBF is 5%, while that of polymeric fluids is 33 lb/Mgal guar. Besides, both fluids contained 4% potassium chloride (KCl). Additionally, Blend-A and Blend-B were prepared by mixing SBF and polymeric fluids in the ratio of 75/25% vol. and 25/75% vol. respectively. Nano-fluids were prepared by adding 20 nm silica nanoparticles, at concentrations of 0.058, 0.24, and 0.4% wt., to the clean fluids. Filtration tests were conducted with a wall mount filter press, and at ambient temperature and 100 psi differential pressure.

Excellent results were displayed with surfactant-based nano-fluids and Blend-A nano-fluids, but their outcome at 0.24 and 0.4% wt. respectively is slightly better. Polymeric nano-fluids and Blend-B nano-fluids revealed very good results, with better outcome at 0.24 and 0.058% wt. respectively. A trial run was made with a commercially available fluid loss additive (polyanionic cellulose, PAC) in polymeric fluids at the same nanoparticle concentrations; the result confirmed that nanosilica facilitates the achievement of a superior filtration property. Furthermore, Blend-A nano-fluid, at 0.058% wt., is selected as the best based on performance evaluation and economic analysis. In conclusion, the selected Blend-A nano-fluid at 0.058% wt. was optimized at lower nanoparticle concentrations (0.02, 0.01 and 0.002% wt.) in order to probe further into its filtration performance. Interestingly, using Blend-A nano-fluid at 0.002% wt., as regards the initial recommendation of 0.058% wt., reduces the cost of nanoparticles required for preparing 1 barrel of this fluid by 96.6%. Therefore, Blend-A nano-fluid is recommended for use at nanoparticles concentration of 0.002% wt.

The application of Blend-A nano-fluid will promote fluid economy, substantially reduce fluid loss and fracture conductivity damage, and enhance production from unconventional reservoirs.
History Matching and Rate Forecasting in Unconventional Oil Reservoirs Using an Approximate Analytical Solution to the Double Porosity Model
Authors: Ogunyomi B. A. , Patzek T. W. , Lake L. W. , Kabir C. S.
Published: October 2014

Production data from most fractured-horizontal wells in gas and liquid-rich unconventional reservoirs plot as straight lines with a one half slope on a log-log plot of rate versus time. This production signature (half slope) is identical to that expected from a one-dimensional linear flow from reservoir matrix to the fracture face, when production occurs at constant-bottomhole pressure. In addition, microseismic data obtained around these fractured wells suggest that an area of enhanced permeability is developed around the horizontal well, and outside this region is an undisturbed part of the reservoir with low permeability. Based on these observations geoscientists have, in general, adopted the conceptual double-porosity model in modeling production from fractured horizontal wells in unconventional reservoirs. The analytical solution to this mathematical model exists in Laplace space but it cannot be inverted back to real-time space without using a numerical inversion algorithm. We present a new approximate analytical solution to the double-porosity model in real-time space and its use in modeling and forecasting production from unconventional-oil reservoirs.

The first step in developing the approximate solution was to convert the systems of partial differential equations for the dual-porosity model into a system of ordinary-differential equations. After which we developed a function that gives the relationship between the average pressures in the high-and the low-permeability regions. Using this relationship, the system of ordinary differential equations was solved and used to obtain a rate/time function that can be used to predict oil production from unconventional reservoirs. The approximate solution was validated with numerical reservoir simulation.

We then performed a sensitivity analysis on the model parameters to understand how the model behaves. Once the model was validated and tested, we applied it to field production data by partially history matching and forecasting the expected ultimate recovery. The rate/time function fits production data and also yields realistic estimates of ultimate oil recovery. We also investigated the existence of any correlation between the model-derived parameters and available reservoir and well completion parameters.
Fully Coupled Finite Element Model to Study Fault Reactivation during Multiple Hydraulic Fracturing in Heterogeneous Tight Formations
Authors: Zhong Ruizhi , Bao Jinqing , Fathi Ebrahim
Published: October 2014

Multiple hydraulic fracturing is a proven stimulation technique to improve hydrocarbon production especially in tight, unconventional hydrocarbon bearing reservoirs. A two dimensional (2D) plane strain model, based on linear elastic fracture mechanics (LEFM), has been developed to study multiple fracture propagation and their impact on reactivation of underground discontinuities such as faults. New model solves coupled non-local relationship between fracture width and net pressure in the fracture and non-linear dependence of fluid flow on fracture width and its linear dependence on pressure gradient using finite element method.

In this paper, multiple hydraulic fracturing with different number of fractures, fracture spacing and reservoir rock properties are considered. It is found that the number of hydraulic fractures and their spacing significantly impacts fractures geometry and ultimately production performance. The impact found to be more pronounced in heterogeneous reservoir with multiple layers. Slip-tendency analysis performed to investigate the possibility of fault reactivation and discontinuities failure in surrounding areas. Simulation results clearly show dynamics of stable and unstable zones around the hydraulic fracturing area. Discontinuities failure in reactivation zones leads to increase the permeability of formation therefore improving hydraulic fracturing performance. This study is a unique approach for our further understanding of multiple hydraulic fracturing, and it is important for the development of sound numerical hydraulic fracturing optimization models.
Cost Effective Treatment of Produced Water Using Co-Produced Energy Sources
Authors: Abdallah Issah
Published: October 2014

Produced water (PW) treatment is a daunting significant challenge that continues to have negative impacts on the oil and gas industry, especially, small oil producers. The total dissolved solids (TDS) in produced water from most oil fields can be higher than 250,000ppm (parts per million) in concentration and may also contain a significant percentage of dissolved organic carbons. Many small oil producing companies operate at the edge of profitability; the current cost of treating a barrel of produced water can exceed $2.50 if the operator has to pay for hauling and disposal. This can make it uneconomical to operate mature producing wells which tend towards high watercuts.

As part of a RPSEA (Research Partnership to Secure Energy for America) research project, a Humidification-Dehumidification (HDH) Unit (figure 3) has been built tested and optimized to treat PW using co-produced heat and active solar energy. This has very low electricity consumption and has been tested to process PW at a cost less than $0.50 per barrel if co-produced, or latent heat sources are used. The HDH Unit effectively treats produced water with varying degrees of inorganic dissolved solids concentration and yields fresh water with TDS in the neighborhood of 400ppm when optimized for maximum throughput which is suitable for most oil field activities, irrigation, and could satisfy other basic human needs of water. The existing 80ft3 HDH Unit can process about 50 barrels of PW per day with high total dissolve solids concentration, and reducing this waste stream into concentrated waste and fresh water. Each pass of PW through the system has approximately 19% efficiency with some variations due to changes in seasonal humidity and temperature.

The process works using simple thermodynamic principles. Air (at atmospheric pressure) has the capacity to tremendously increase water vapor saturation pressure to about 50Kpa when the temperature is about 180°F. Consequently, the efficiency of the unit is primarily contingent on ambient temperature and relative humidity. The system uses the high solar radiations prevalent in the Southwest United States to heat PW to about 180°F which is then pumped into an 80ft3 stainless steel that has evaporation and condensation compartments; air is then pumped into the Unit through the opposite direction (to the water) for the humidification of the air at elevated temperature. The heated and humidified air is then cooled to or below dew point to produce fresh water.
Graptolite shale - worldwide distributed Ordovician and Silurian source rock
Authors: Agapitov I.
Published: October 2014

Graptolite shales are a type of fossil shales that contain a large number of graptolite imprints and remains. These deposits are characterized by high TOC contents (Corg = 2–18%). Based on the data of many studies, graptolite shales are one of the main hydrocarbon sources that formed oil and gas fields in Paleozoic deposits around the world, e.g., the Silurian graptolite shales make up to 9–15% of all hydrocarbons that form the oil and gas fields in the largest petroleum basins.

The main accumulation areas of graptolite shales during the Ordovician were the margins of Baltica, Laurentian, and Gondwana (Yapetus Ocean shelf). One of the belts (northern) extended from the southern periphery of the Baltic Shield to the Appalachian Basin; another (southern) belt stretched from the sedimentary basins of the African–Arabian margin of Gondwana to the shelf and continental slope of southern Laurentia, the present-day Western Interior Coal Region, Permian basin, and Ouachita belt. In the Silurian, the southern (northern Gondwanan) belt began to play the leading role, while another northern belt incorporated the southern regions of Baltica and the microcontinents approaching to it (Armorica, Perunica, and Iberica). In the sedimentary basins of Laurentia, Silurian graptolite shales were not widespread; they are reported only for east Greenland and in the Michigan basin. The contribution of Paleozoic graptolite shales into the generation of hydrocarbons that formed multiple oil and gas fields worldwide is quite high. Based on the data of G. Ulmishek and H. Klemme (1991), oil-and-gas source rocks of Ordovician and Silurian ages, which are mostly graptolite shales, produced up to 9% of all the hydrocarbon reserves discovered by the late 20th century. For particular regions, this contribution was even more. It is believed that Silurian graptolite shales produced 80 to 90% of the hydrocarbons stored in giant oil field of North Africa. The Silurian graptolite shales are also thought to have played the main role in the formation of the South Pars/North Field gas condensate field in the Persian Gulf, which is the largest field for natural gas in the world.

During work with more than 41 publications schemes of distribution of graptolitic shales in Ordovician and Silurian was composed. Such knowledge about source rock is one of the many steps to Petroliferous basins insight.
Characterization and Modeling of a Thick Carbonate Transition Zone
Authors: Gomes Jorge C.
Published: October 2014

Naturally, tight carbonate reservoirs exhibit thick transition zones [TZ's] that contain large amounts of oil initially in place [OIIP] and hence significant addition of reserves could be left behind. TZ's are characterized by two-phase flow of both water and oil and there are experimental and field evidences indicating that wettability variation with respect to height above free water level [FWL] is a reality. This variation has to be accounted for in the dynamic model to accurately capture the reservoir performance. However, in real field applications, the situation becomes more complicated while production due to hysteresis effect.

To model rock and fluid property [SCAL/PVT] variations across TZ's and its effect on fluid distribution and ultimate oil recovery, a thorough criterion is required to capture all these variations and their inter-relationships. This was done by developing a mechanistic flow model using a unique approach to model wettability variation with respect to depth and space, taking into account thick TZ. This is extremely important for all professionals involved in field development activities to better understand the fluid flow behavior of porous carbonates at different heights above the FWL, as a function of oil trapping and rock wettability. The simulation work presented here is a continuation of the research done by Carvalho, Dias et al. [1] on the behavior of mixed-wet, oil-wet and water-wet systems for a cyclic carbonate reservoir with different rock types.
Rearing broiler chickens under monochromatic blue light improve performance and reduce fear and stress during pre-slaughter handling and transportation
Authors: Mohamed R.A. , Eltholth M.M. , El-Saidy N.R.
Published: October 2014

The aim of this study was to evaluate the effect of monochromatic light on
broiler performance, fear and stress response during pre-slaughter handling
and transportation. Two thousand unsexed one-day old Cobb broiler chicks were
used. At day 34, two hundreds broilers of similar live body weight were
selected and divided into two equal groups (2 group x 5 replicates). Broilers
were reared under white light (WL) from 0-34 day. From 35 to 49 day, the
first group was reared under WL and the second group under blue light (BL).
Final body weight (FBW), tonic immobility reactions (TI), respiratory rate
(RR), heterophils to lymphocytes (H/L) ratio and interlukien-1? (IL-1?) were
estimated at day 49 before and after transportation. After transportation,
weight of internal organs (liver, spleen, heart and bursa of fabricius) as a
percentage of FBW was calculated. Results showed that there was a significant
(P<0.05) increase in FBW and reduced weight loss due to transportation in
broilers reared under BL. In broilers reared under BL: TI duration, RR, H/L
ratio, IL-1? and weight of internal organs (except the heart) were
significantly (P < 0.05) lower. The interaction effect of light and
transportation on TI duration, RR, lymphocytes, H/L ratio and IL-1? were
significant (P < 0.05). Therefore, it is suggested that BL may be a good tool
for improving welfare and mitigating stress not only in pre-slaughter
handling but also during transportation of broilers.
Impact of copper cyanide on the key metabolic enzymes of freshwater fish Catla catla (Hamilton)
Authors: Dube Praveen , Shwetha A. , Hosetti B.B.
Published: October 2014

Short term toxicity experiments were conducted to study the effect of metal
cyanide complex (copper cyanide) on the key metabolic enzymes viz., lactate
dehydrogenase (LDH), succinate dehydrogenase (SDH), glucose-6 phosphate
dehydrogenase (G6PDH), aspartate amino transferase (AST) alanine amino
transferase (ALT), acid phosphatase (AcP) and alkaline phosphatase (ALP)
activity in Catla catla juveniles. A total of 60 fingerlings were (2?0.5 cm;
1.5?0.2 g) exposed to two sublethal concentrations (0.253 and 0.152 mg/L) for
a period of 15 days. Copper cyanide had significant (P> 0.05) effect on the
key metabolic enzymes, the highest activities were observed in the group
exposed to 0.253 mg/L. Results suggest that metal cyanide complex
significantly altered enzyme activities of fish in both the sublethal
concentrations.
Influence of inter-row spacing and cultivar on the productivity of soybean
Authors: Kolaric Lj. , Zivanovic Lj. , Popovic V. , Ikanovic J. , Srebric M.
Published: October 2014

Influence of inter-row spacing on a productivity of soybean yield was studied
on the experimental field on low carbonate chernozem soil. The greatest grain
weight per plant (13.22 g) was achieved at the smallest row spacing. It
decreased at higher row spacing, except for cultivar Balkan, where value of
these parameters was the highest (13.09 g). The highest grain yield (4,868 kg
ha-1) was determined at the 20 cm inter-row width. It decreased equally at
bigger row spacing for 7.0-12.9%. The highest grain yield was achieved with
Balkan cultivar (4,773 kg ha-1), and the lowest with Dragana cultivar (4,284
kg ha-1).
Genetic variability of red clover seedlings in relation to salt stress
Authors: Mandic V. , Krnjaja V. , Bijelic Z. , Tomic Z. , Simic A. , Ruzic-Muslic D. , Stanojkovic A.
Published: October 2014

Red clover is highly salt-sensitive plant, especially during germination and
early seedling growth stages. The aim of this investigation was to estimate
the effects of different saline conditions (0, 50, 100, 150, and 200mM NaCl)
on germination and early seedling growth in four red clover varieties
(Kolubara, K-32, K-17 and K-39). Germination test was conducted in the
laboratory conditions using sterile plastic vessels on filter paper moistened
with 10ml of the appropriate salt test solutions. It was observed that the
germination energy (GE), germination (G), percentage of dead or infected
seeds (DIS), normal seedlings (NS), root length (RL), shoot length (ShL),
fresh weight (FW) and dry weight of seedling (DW) and seedling vigor index
(SVI) were significantly decreased with increasing concentrations of NaCl in
the growing medium. The tested varieties of red clover showed different NaCl
tolerance at the seedling stage. Generally, studied red clover varieties are
very sensitive to salt, especially K-32 which has the lowest values for GE,
G, NS and SVI and highest for DIS. Variety K-17 proved to be a variety that
the best tolerates conditions of salt stress because the values for GE, G,
NS, RL and SVI were highest. Testing of varieties of red clover in the early
seedling growth at different concentrations of NaCl in the growing medium
could be helpful in the identification and selection of varieties for
cultivation on saline soils.
Cognitive Responses to Partitioned Pricing of Consumption Taxes: Consequences for State and Local Tax Revenues
Authors: Blanthorne Cynthia , Roberts Michael L.
Published: October 2014

How do taxpayers respond cognitively to add-on sales taxes versus all-inclusive excise taxes? If structural variations produce cognitive differences, then do the differences affect buying behavior? These are important questions because consumer spending drives the U.S. economy and directly determines the amount of tax revenues collected from consumption taxes.

If the negative opinion that people have about taxes (Tax Foundation 2009) increases the saliency of the tax, then an add-on sales tax might decrease consumer spending more than an all-inclusive excise tax pricing structure. Instead, results suggest that demand is higher when the add-on component is a sales tax as compared to an excise tax that is embedded into the total price. The effects on demand are even more pronounced and people recall lower prices when the add-on sales tax is presented as a percentage of the base price—as is generally the case in the U.S.—rather than as an additional currency component.

Data Availability: Contact the authors.
Cosmopolitan Whiteness
Authors: Saraswati L. Ayu
Published: October 2014

Previous scholarship on the immense popularity of skin-whitening frames this practice as revealing women's desire to emulate whiteness and upper class white populations (Burke 1996; Peiss 1998; Hall 2005). Others have focused on whitening practices to highlight the working of racialized color hierarchy and European/Euro-American hegemony in local and global contexts (Hunter 2005; Pierre 2008; Glenn 2009;). This article breaks away from these established theoretical trajectories by arguing that desire for “whiteness” is not the same as desire for “Caucasian whiteness.” Examining advertisements for skin-whitening products in the Indonesian version of Cosmopolitan and skin-tanning products in the American version of Cosmopolitan, I point out the construction of “cosmopolitan whiteness.” Whiteness is not simply racialized or nationalized as such, but transnationalized. Whiteness is represented as “cosmopolitanness,” embodying transnational mobility.
What Makes for Powerful Classrooms, and How Can We Support Teachers in Creating Them? A Story of Research and Practice, Productively Intertwined
Authors: Schoenfeld Alan H.
Published: October 2014

This article and my career as an educational researcher are grounded in two fundamental assumptions: (a) that research and practice can and should live in productive synergy, with each enhancing the other, and (b) that research focused on teaching and learning in a particular discipline can, if carefully framed, yield insights that have implications across a broad spectrum of disciplines. This article begins by describing in brief two bodies of work that exemplify these two fundamental assumptions. I then elaborate on a third example, the development of a new set of tools for understanding and supporting powerful mathematics classroom instruction—and by extension, powerful instruction across a wide range of disciplines.
The record 2013 Southern Hemisphere sea-ice extent maximum
Authors: Reid Phil , Stammerjohn Sharon , Massom Rob , Scambos Ted , Lieser Jan
Published: October 2014

Observations of Southern Hemisphere sea ice from passive microwave satellite measurements show that a new record maximum extent of 19.58 x 106 km2 was reached on 30 September 2013; the extent is just over two standard deviations above the 1979-2012 mean and follows a similar record (19.48x 106km2) in 2012. On the record day in 2013, sea-ice extent was greater than the 30 year average (1981-2010) in nearly all Southern Ocean regions. For the year as a whole, Southern Hemisphere sea-ice area and extent were well above average, and numerous monthly and daily records were broken. Analysis of anomaly patterns and the atmospheric and oceanic events suggests that a sequence of regional wind and cold-freshened surface waters is likely responsible for the record maximum and the generally high 2013 extent. In particular, the Ross Sea sector experienced a combination of cold southerly winds associated with the position and depth of the Amundsen Sea low, and lower than normal sea surface temperatures (up to 2°C below normal). The resulting very high anomaly in ice extent in this region was a major component of the overall record maximum.
New Power Quality Analysis Method Based on Chaos Synchronization and Extension Neural Network
Authors: Wang Meng-Hui , Yau Her-Terng
Published: October 2014

A hybrid method comprising a chaos synchronization (CS)-based detection scheme and an Extension Neural Network (ENN) classification algorithm is proposed for power quality monitoring and analysis. The new method can detect minor changes in signals of the power systems. Likewise, prominent characteristics of system signal disturbance can be extracted by this technique. In the proposed approach, the CS-based detection method is used to extract three fundamental characteristics of the power system signal and an ENN-based clustering scheme is then applied to detect the state of the signal, i.e., normal, voltage sag, voltage swell, interruption or harmonics. The validity of the proposed method is demonstrated by means of simulations given the use of three different chaotic systems, namely Lorenz, New Lorenz and Sprott. The simulation results show that the proposed method achieves a high detection accuracy irrespective of the chaotic system used or the presence of noise. The proposed method not only achieves higher detection accuracy than existing methods, but also has low computational cost, an improved robustness toward noise, and improved scalability. As a result, it provides an ideal solution for the future development of hand-held power quality analyzers and real-time detection devices.
Development of 3D in Vitro Technology for Medical Applications
Authors: Ou Keng-Liang , Hosseinkhani Hossein
Published: October 2014

In the past few years, biomaterials technologies together with significant efforts on developing biology have revolutionized the process of engineered materials. Three dimensional (3D) in vitro technology aims to develop set of tools that are simple, inexpensive, portable and robust that could be commercialized and used in various fields of biomedical sciences such as drug discovery, diagnostic tools, and therapeutic approaches in regenerative medicine. The proliferation of cells in the 3D scaffold needs an oxygen and nutrition supply. 3D scaffold materials should provide such an environment for cells living in close proximity. 3D scaffolds that are able to regenerate or restore tissue and/or organs have begun to revolutionize medicine and biomedical science. Scaffolds have been used to support and promote the regeneration of tissues. Different processing techniques have been developed to design and fabricate three dimensional scaffolds for tissue engineering implants. Throughout the chapters we discuss in this review, we inform the reader about the potential applications of different 3D in vitro systems that can be applied for fabricating a wider range of novel biomaterials for use in tissue engineering.
Epoxidized Vegetable Oils Plasticized Poly(lactic acid) Biocomposites: Mechanical, Thermal and Morphology Properties
Authors: Chieng Buong , Ibrahim Nor , Then Yoon , Loo Yuet
Published: October 2014

Plasticized poly(lactic acid) PLA with epoxidized vegetable oils (EVO) were prepared using a melt blending method to improve the ductility of PLA. The plasticization of the PLA with EVO lowers the Tg as well as cold-crystallization temperature. The tensile properties demonstrated that the addition of EVO to PLA led to an increase of elongation at break, but a decrease of tensile modulus. Plasticized PLA showed improvement in the elongation at break by 2058% and 4060% with the addition of 5 wt % epoxidized palm oil (EPO) and mixture of epoxidized palm oil and soybean oil (EPSO), respectively. An increase in the tensile strength was also observed in the plasticized PLA with 1 wt % EPO and EPSO. The use of EVO increases the mobility of the polymeric chains, thereby improving the flexibility and plastic deformation of PLA. The SEM micrograph of the plasticized PLA showed good compatible morphologies without voids resulting from good interfacial adhesion between PLA and EVO. Based on the results of this study, EVO may be used as an environmentally friendly plasticizer that can improve the overall properties of PLA.
Land Cover Characterization and Mapping of South America for the Year 2010 Using Landsat 30 m Satellite Data
Authors: Giri Chandra , Long Jordan
Published: October 2014

Detailed and accurate land cover and land cover change information is needed for South America because the continent is in constant flux, experiencing some of the highest rates of land cover change and forest loss in the world. The land cover data available for the entire continent are too coarse (250 m to 1 km) for resource managers, government and non-government organizations, and Earth scientists to develop conservation strategies, formulate resource management options, and monitor land cover dynamics. We used Landsat 30 m satellite data of 2010 and prepared the land cover database of South America using state-of-the-science remote sensing techniques. We produced regionally consistent and locally relevant land cover information by processing a large volume of data covering the entire continent. Our analysis revealed that in 2010, 50% of South America was covered by forests, 2.5% was covered by water, and 0.02% was covered by snow and ice. The percent forest area of South America varies from 9.5% in Uruguay to 96.5% in French Guiana. We used very high resolution (<5 m) satellite data to validate the land cover product. The overall accuracy of the 2010 South American 30-m land cover map is 89% with a Kappa coefficient of 79%. Accuracy of barren areas needs to improve possibly using multi-temporal Landsat data. An update of land cover and change database of South America with additional land cover classes is needed. The results from this study are useful for developing resource management strategies, formulating biodiversity conservation strategies, and regular land cover monitoring and forecasting.
Temperature Sensing in Seawater Based on Microfiber Knot Resonator
Authors: Yang Hongjuan , Wang Shanshan , Wang Xin , Wang Jing , Liao Yipeng
Published: October 2014

Ocean internal-wave phenomena occur with the variation in seawater vertical temperature, and most internal-wave detections are dependent on the measurement of seawater vertical temperature. A seawater temperature sensor based on a microfiber knot resonator (MKR) is designed theoretically and demonstrated experimentally in this paper. Especially, the dependences of sensing sensitivity on fiber diameter and probing wavelength are studied. Calculated results show that sensing sensitivity increases with the increasing microfiber diameter with the range of 2.30–3.91 μm and increases with the increasing probing wavelength, which reach good agreement with results obtained by experiments. By choosing the appropriate parameters, the maximum sensitivity measured can reach to be 22.81 pm/°C. The seawater temperature sensor demonstrated here shows advantages of small size, high sensitivity, easy fabrication, and easy integration with fiber systems, which may offer a new optical method to detect temperature of seawater or ocean internal-wave phenomenon and offer valuable reference for assembling micro sensors used for other parameters related to seawater, such as salinity, refractive index, concentration of NO3− and so on.
Sensitivity-Improved Strain Sensor over a Large Range of Temperatures Using an Etched and Regenerated Fiber Bragg Grating
Authors: Wang Yupeng , Qiao Xueguang , Yang Hangzhou , Su Dan , Li Ling , Guo Tuan
Published: October 2014

A sensitivity-improved fiber-optic strain sensor using an etched and regenerated fiber Bragg grating (ER-FBG) suitable for a large range of temperature measurements has been proposed and experimentally demonstrated. The process of chemical etching (from 125 µm to 60 µm) provides regenerated gratings (at a temperature of 680 °C) with a stronger reflective intensity (from 43.7% to 69.8%), together with an improved and linear strain sensitivity (from 0.9 pm/με to 4.5 pm/με) over a large temperature range (from room temperature to 800 °C), making it a useful strain sensor for high temperature environments.
Support for Sport Events and the Economy of Appearances: A Case Study of the 2011 World Rally Championship in Australia
Authors: Reis Arianne , Sperandei Sandro
Published: October 2014

This article proposes an alternative way of analyzing the support commonly given by different members of host communities to staging large-scale sport events. It includes the contextualization of this phenomenon within the concept of the “society of the spectacle” and its
derivate economy of appearances. Drawing from Debord we argue that the desire to be on the “world-stage,” be labeled as “international,” and win a competition with local neighbors may overrule the tangible losses often incurred by staging such large-scale events. We
present data from a survey of 226 local business managers from the relatively small community of Coffs Coast in New South Wales, Australia, as well as analysis of local newspaper articles that support the premise of the economy of appearances. This theoretical position has hence proven useful
in understanding some “hidden” players in this game and can be a useful tool for further developing research in this field.
Guanxi and the Organization of Chinese New Year Festivals in England
Authors: Fu Yi , Long Philip , Thomas Rhodri
Published: October 2014

This article explores how Chinese diaspora communities use guanxi, a unique Chinese interpretation of personal relationships, in the organization of Chinese New Year (CNY) festivals in England. A case-study approach that incorporated mixed qualitative methods was used to investigate
the interactions and interrelationships between the ethnic Chinese communities involved in the organization of CNY festivals in five English cities. The article argues that Chinese diaspora communities use their guanxi to establish collaboration at CNY festivals. However, the process
of organizing CNY festivals has also exposed divisions among Chinese communities. The article proposes that guanxi has important implications for the relationships among Chinese diaspora communities in the context of CNY festivals. Although it facilitates collaboration and promotes
solidarity among Chinese communities, it may also intensify competition for power. Diaspora festivals in general are a neglected area of research and this article is the first to study the organization of Chinese New Year festivals in detail.
Papua New Guinea's Indigenous Cultural Festivals: Cultural Tragedy or Triumph?
Authors: Whitford Michelle , Dunn Ashley
Published: October 2014

Indigenous cultural festivals are increasingly being recognized for their contribution to the growth and vitality of communities around the globe. Such festivals invigorate the communication and celebration of indigenous culture, tradition, and rituals. Additionally, indigenous cultural
festivals are often used as a draw card to attract tourists to a host destination and contribute to the development of the region. In Papua New Guinea (PNG), festivals have long been essential to community life and are fundamental in sharing and sustaining Indigenous culture. More recently,
local communities and the PNG Government alike are recognizing that these festivals have the capacity to facilitate development of the country's embryonic tourism and event industry. The purpose of this qualitative research was to identify and examine cultural festivals in PNG, to develop
a footprint of indigenous cultural festivals in PNG, and explore the extent to which tourism influences the cultural commodification of indigenous cultural festivals in PNG. Weaver and Lawton's cultural commodification model provided theoretical scaffolding for the development of the PNG Indigenous
Festival Cultural Commodification Framework, which revealed that overall, cultural festivals in PNG are a relatively unspoiled resource. To date, tourism has had little influence on the festivals, which celebrate, among other things, PNG culture and traditions. However as tourism in PNG gains
momentum, arguably a key issue will be the extent to which tourism development adopts the principles of sustainability and, concomitantly, avoids turning a triumph into a tragedy as a result of over commodification of PNG indigenous cultural festivals.
Controlling the Delivering of Projects in Mega-Events: An Application on Expo 2015
Authors: Locatelli Giorgio , Mancini Mauro
Published: October 2014

The preparation of mega-events like Olympic Games, music festivals, or world expositions requires the successful and timely delivering of many correlated projects: buildings, ICT infrastructure, marketing projects, etc. The international market is increasingly characterized by large and mega-events. The size of these events escalates the complexity of management, often causing budget overruns and scope reduction. As a consequence it is fundamental to effectively monitor the progress of the entire program to react in case the progress does not follow the expected baseline. Project-controlling methodologies are well analyzed in the literature with respect to individual projects. For that which concerns the overall delivery of correlated projects (i.e., a program) the literature provides strategic and operational guidelines; however, far too little attention has been paid to developing quantitative methodology to control their execution phase. The purpose of this article is to review recent research into event planning and program management to propose a quantitative approach, based on the Petri nets and dynamic systems, to obtain the project envelope, a fundamental tool to assess and manage the progress of a program. The methodology is implemented on a real case study: EXPO 2015.
Subject Areas and Future Research Agendas in Exhibition Research: Visitors' and Organizers' Perspectives
Authors: Lee Myong Jae , Lee Sanggun
Published: October 2014

This thematic review of exhibition literature highlights major research themes in current exhibition research and directions for future exhibition research. A total of 55 exhibition studies published in academic journals and conference proceedings were contents analyzed for the review.
A number of exhibition studies have targeted exhibition visitors and organizers. This thematic review presents four major research themes: (1) motives for exhibition visit, (2) the role of visitors in the buying center, (3) exhibition service marketing, and (4) exhibition site selection. Research
agendas for future exhibition research are discussed.
Embedded Catheters: Minimizing Excessive Embedment Time and Futile Placement While Maintaining Procedure Benefits
Authors: Crabtree John H. , Burchette Raoul J. , Siddiqi Rukhsana A.
Published: October 2014

Background

Embedding peritoneal catheters far in advance of anticipated need may successfully commit patients to their modality choice and reduce central venous catheter use but can be complicated by excessive embedment periods and futile catheter placement.

Objective

Embedded catheter outcomes were studied to identify factors that minimize inordinate embedment time and futile placement while maintaining procedure benefits.

Methods

Clinical and laboratory data were examined in 107 patients with embedded catheters that were either externalized, remained embedded, or were futilely placed.

Results

Externalization of 84 catheters was performed after a median embedment period of 9.4 months. Flow dysfunction occurred in 14.3% of externalized catheters. Overall function rate was 98.8% after laparoscopic revision. One patient changed their mind about modality choice. Except for 1 patient hospitalized acutely in a facility unfamiliar with embedded catheters, none remaining on a peritoneal dialysis pathway initiated dialysis with a central venous catheter. Including catheters with extremely long embedment periods, the incidence of futile placement was 13.1%. Multiple regression analysis identified estimated glomerular filtration rate (eGFR) and serum albumin as the 2 variables best associated with catheter embedment duration (r2 = 0.44, p < 0.0001). Diabetic nephropathy was statistically more likely to be associated with lower serum albumin values ( p < 0.0001); however, no association was noted between diabetic status and embedment duration ( p = 0.62).

Conclusions

Timing of the embedment procedure should include appraisal of both eGFR and serum albumin. Appropriate consideration of these values together may help minimize excessive embedment periods and decrease futile placements while preserving procedure benefits.
Oral Astaxanthin Supplementation Prevents Peritoneal Fibrosis in Rats
Authors: Wakabayashi Keiichi , Hamada Chieko , Kanda Reo , Nakano Takanori , Io Hiroaki , Horikoshi Satoshi , Tomino Yasuhiko
Published: October 2014

Background

Preventing peritoneal damage during peritoneal dialysis is critical. Reactive oxygen species (ROS) have an important role in peritoneal damage; however, few studies have investigated this. We aimed to determine the effects of oral astaxanthin (AST) supplementation in a peritoneal fibrosis (PF) rat model.

Methods

Thirty-seven Sprague-Dawley rats were divided into 5 groups: Control 1 (fed a normal diet without stimulation), Control 2 (fed an AST-supplemented diet without stimulation), Group 1 (fed a normal diet with 8% chlorhexidine gluconate [CG] stimulation for 3 weeks), Group 2 (fed a 0.06% AST-supplemented diet with CG stimulation), and Group 3 (fed a 0.06% AST-supplemented diet that was initiated 4 weeks before CG stimulation). Peritoneal fibrosis, vascular proliferation, and fibrosis-related factor expression were examined.

Results

Peritoneal thickness was significantly suppressed by AST supplementation. Astaxanthin diminished the number of CD68-, 8-hydroxy-2'–deoxyguanosine (8-OHdG)-, and monocyte chemoattractant protein-1 (MCP-1)-positive cells. Type 3 collagen, tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and MCP-1 mRNA expression was significantly lower in Group 3 than in Group 1. Increased transforming growth factor-β (TGF-β) and Snail mRNA expression, vascular density, and the number of α–smooth muscle actin (α–SMA)-positive cells were also decreased in Group 3.

Conclusion

Astaxanthin suppressed PF development through the inhibition of inflammation and oxidation in PF rats. It appears that the anti-oxidative agent AST may be useful for the prevention of peritoneal damage.
Comparing kinetic profiles between bifunctional and binary type of Zn(salen)-based catalysts for organic carbonate formation
Authors: Martín Carmen , Kleij Arjan W
Published: October 2014

Zn(salen) complexes have been employed as active catalysts for the formation of cyclic carbonates from epoxides and CO2. A series of kinetic experiments was carried out to obtain information about the mechanism for this process catalyzed by these complexes and in particular about the order-dependence in catalyst. A comparative analysis was done between the binary catalyst system Zn(salphen)/NBu4I and a bifunctional system Zn(salpyr)·MeI with a built-in nucleophile. The latter system demonstrates an apparent second-order dependence on the bifunctional catalyst concentration and thus follows a different, bimetallic mechanism as opposed to the binary catalyst that is connected with a first-order dependence on the catalyst concentration and a monometallic mechanism.
AN IMPROVED ADAPTIVE TRUST-REGION METHOD FOR UNCONSTRAINED OPTIMIZATION
Authors: Esmaeili Hamid , Kimiaei Morteza
Published: October 2014

In this study, we propose a trust-region-based procedure to solve unconstrained optimization problems that take advantage of the nonmonotone technique to introduce an efficient adaptive radius strategy. In our approach, the adaptive technique leads to decreasing the total number of iterations, while utilizing the structure of nonmonotone formula helps us to handle large-scale problems. The new algorithm preserves the global convergence and has quadratic convergence under suitable conditions. Preliminary numerical experiments on standard test problems indicate the efficiency and robustness of the proposed approach for solving unconstrained optimization problems.
GLOBAL EXISTENCE RESULTS FOR FUNCTIONAL DIFFERENTIAL INCLUSIONS WITH STATE-DEPENDENT DELAY
Authors: Benchohra Mouffak , Henderson Johnny , Medjadj Imene
Published: October 2014

Our aim in this work is to study the existence of solutions of a functional differential inclusion with state-dependent delay. We use the Bohnenblust–Karlin fixed point theorem for the existence of solutions.
SCIENTISTS AND ENGINEERS IN CONVERGENCE TECHNOLOGIES IN KOREA: WHERE ARE THEY GOING AND HOW DO THEY COLLABORATE?
Authors: Lee Jungmann , Om Kiyong , Choi Minseok , Song Chanhoo , Kim Kwanyoung
Published: October 2014

Today convergence technologies have become a major issue in science policy. This paper describes the current state of scientific collaboration in convergence technologies among researchers in South Korea, by conducting survey and the Social Network Analysis (SNA) with a data set of 1,095 researchers who have involved in the development of the convergence technologies. The main research findings are fivefold. First, dominant numbers of researchers are involved in convergence technology with IT because IT is recognized as the most competitive technology in Korea. Second, mobility of researchers is active in convergence technologies. Third, it is found that the researchers in convergence technologies are more productive in terms of the number of research papers per capita than those in other scientific fields. Fourth, they, however, show limited research collaboration, compared with their high productivity. Finally, the members of the network in convergence technologies are closer to each other than those in other scientific fields, but most of their collaborative relationships remain bilateral rather than triangular. Only a few researchers act as hubs, revealing that collaborative research relationship in convergence technologies in Korea is highly concentrated. At the last part, some policy recommendations to promote research collaboration in convergence technologies are discussed.
MEASURING INNOVATION PERFORMANCE OF DEVELOPING REGIONS: LEARNING AND CATCH-UP IN PROVINCES OF IRAN
Authors: Ghazinoory Sepehr , Riahi Parisa , Azar Adel , Miremadi Tahereh
Published: October 2014

Common innovation performance measures, which are based on research and development activities, are not relevant to dominant innovation behaviour of developing countries. The main functions of the innovation system of developing countries are capture, imitation, learning by doing and diffusion of knowledge, to reduce technology gaps with technology frontiers. Hence, the purpose of measuring innovation performance in a developing geographical area should be the evaluation on its success in technological learning and catching-up. Using the learning and technology gap concepts, in this paper we develop a novel model of measuring innovation performance of developing countries/regions, based on common regional statistics. In the virtual absence of mandatory firm level surveys, this model can provide a useful method to compare the innovation behaviour of regions for policymaker. Running the model with the data from the Iranian provinces, the paper concludes each province has its own specific innovation behaviour stemming from different historical development paths and geographical characteristics.