bluuebunny/crossref_metadata_2025 huggingface dataset:
poder infraestructural del ferrocarril en Chile: una mirada histórica
Authors: Guajardo Soto Guillermo
Published: June 2024

Este artículo entrega una reflexión histórica sobre el papel que cumplió la infraestructura del ferrocarril en el despliegue del poder territorial del Estado chileno entre las décadas de 1850 y 1970. Sus objetivos son, primero, aportar una reflexión sobre la historia territorial de Chile a través de la historia del ferrocarril, también destacar la persistencia histórica de las infraestructuras y finalmente entender el ferrocarril como un medio de transporte que entregó una base material para el Estado. Se basa en los resultados de investigaciones del autor, el estado del arte del último medio siglo sobre la historia del ferrocarril y en conceptos provenientes de la ingeniería, sociología y geografías históricas sobre el concepto de infraestructura. Se plantea que entre las décadas de 1880 y 1930 se estructuró un proyecto gubernamental para conectar longitudinalmente el país por el interior, enfrentando las dimensiones geográficas y económicas transversales del territorio. Desde el decenio de 1950 esta conexión enfrentó la competencia de otros medios, hasta que ser cancelado por la dictadura cívico militar (1973-1990) que implantó la subsidiariedad en el transporte para traspasar el tráfico a la carretera y desconectar el proyecto ferroviario longitudinal.
DESIGNING LANDLINKS: Strategies for enhancing the natural and cultural heritage along the edge of the Llanquihue Lake (Chile)
Authors:   , Muñoz Balbontín Sofía
Published: June 2024

The following thesis aims to study the landscape on the Llanquihue Lake edge, situated in the North Patagonia of Chile. Therefore, the investigation analyzes the different systems that characterize the lake edge, focusing on facing the fragmentation of the natural and cultural heritage systems. This fragmentation is a discontinuity that produces the degradation of the heritage, due to its insolation or friction with other systems such as the rural and urban. The importance of reconnecting and reconciling them. Consequently, the thesis proposes a design strategy based on the operational concept of ‘landlinks’. The strategy works on different scales, from the vast to the local one, to approach the fragmentation of the lake edge. It enhances aban- doned spaces, fosters recreation, and makes accessible different kinds of landscapes. The design strategy does not oppose one system with another, it connects them, making them coexist in structured systems that allow a healthy transition.
Optimización dinámica de operaciones same-day delivery integradas con recogida de productos
Authors:   , Gaete Silva Matías Gonzalo
Published: June 2024

En este trabajo, estudiamos el problema de same-day delivery (SDD) integrado con recogida de productos (SDDP-PP). El SDDP-PP es un modelo de planificación operacional enfrentado por un operador logístico que ejecuta e-commerce desde un centro de distribución (CD). El operador logístico recibe dinámicamente solicitudes de entrega a domicilio y recogida de productos hacia el CD durante el día. Para ello, dispone de una flota de vehículos para atender las solicitudes. Las solicitudes de entrega se caracterizan por tener tiempos límite de entrega ajustados. Las solicitudes de recogida representan devoluciones, residuos o productos de proveedores que abastecen al operador logístico. Estudiamos integrar la operación de recogida con la de entrega y así aprovechar las economías de consolidación geográficas presentes en la operación de ruteo de los vehículos. El objetivo es maximizar el beneficio esperado por atender solicitudes, asumiendo que el operadorlogístico asigna un beneficio distinto a cada tipo de solicitud. Para resolver este modelo se requiere de políticas de decisión dinámicas que sean reactivas frente al estado de la flota y las solicitudes del sistema y también proactivas frente al arribo futuro de solicitudes. Dada esta naturaleza dinámica de decisión y los aspectos geográficos y temporales presentes en el estado del sistema, proponemos una política basada en el método Multiple Scenario Approach para anticipar eventos futuros combinado con la heurística Adaptive Large Neighborhood Search para optimizar los planes de rutas. Nuestro método de solución es evaluado en instancias computacionalmente simuladas con diferentes tasas de arribo y distribuciones espaciales de solicitudes, tamaño de flota y beneficios por atendercada tipo de solicitud. Comparamos el beneficio de integrar recogidas en la operación SDD versus operaciones que dividen la flota de vehículos para realizar SDD y recogidas por separado. Para un operador logístico que valora el doble atender solicitudes de entrega versus atender solicitudes de recogida, nuestros resultados computacionales muestran que integrar recogidas en la operación mejora el beneficio obtenido en un 6.9% versus una operación que solo realiza SDD sin considerar recogidas. Esta mejora disminuye cuando: aumenta la tasa de arribo de solicitudes, disminuye el número de vehículos o aumenta la razón entre el beneficio por atender solicitudes de entrega y recogida. Además, concluimos que integrar recogidas con entregas versus separar ambas operaciones mejora el beneficio en un 7.7%.
Síntesis de productos químicos de alto valor agregado mediante reacciones One-Pot Tándem condensación/hidrogenación sobre catalizadores del tipo MOFS
Authors:   , Pazo Carballo César Alexander
Published: June 2024

La transformación catalítica de la biomasa se presenta como una ruta eficiente y selectiva para la generación de combustibles no convencionales y de productos químicos con valor agregado. El acoplamiento C-C de moléculas derivadas de la biomasa y posterior hidrogenación se ha planteado hoy día como una reto científico y novedoso. En este trabajo de tesis doctoral se estudió la actividad catalítica de las mallas metal-orgánicas (MOFs por sus siglas en inglés) sobre la condensación aldólica del benzaldehído y acetona sobre catalizadores mono- y bimetálicos-UiO-66 de Zr(IV), Hf(IV) y Ce(IV). Todos los catalizadores fueron sintetizados por el método solvotermal y se caracterizaron utilizando diversas técnicas analíticas. La actividad catalítica de las reacciones de condensación e hidrogenación se llevaron a cabo en un reactor discontinuo. Los resultados mostraron que la mayor actividad se observó sobre el Hf-UiO-66 debido al carácter oxofílico del metal, mostrando una mayor velocidad inicial de reacción para dar benzalacetona sin desactivar sus sitios activos. Efecto contrario se observó al cambiar el enlazador orgánico (ácido-2,5-piridin tereftálico) conllevando a cambios en la actividad catalítica y selectividad. En base a estos resultados, se seleccionó al Hf-UiO-66 como base del MOF con mejor potencial para su uso como soporte de las nanopartículas de ReOx- y ReOx-Pd. La caracterización fisicoquímica puso de manifiesto que las propiedades de estos materiales tras la adición con éxito de estas especies químicas, no alteró la cristalinidad del soporte microporoso. La evaluación catalítica de estos materiales en la hidrogenación de la benzalacetona mostró que todos presentan actividad catalítica con pequeñas variaciones en la selectividad hacia la formación de productos químicos de interés industrial. Finalmente, el ReOx-Pd/UiO-66 se evaluó en la reacción one-pot tándem condensación/hidrogenación mostrando actividad para ambas reacciones partiendo de la mezcla de sustratos benzaldehído/acetona.
СОВРЕМЕННИК БУДУЩЕГО
Authors: Фельдман Д. М.
Published: June 2024

Александр Романович Беляев вошел в историю отечественной литературы как писатель-фантаст. Так его обычно характеризовали авторы многочисленных публикаций в советскую эпоху.
Exploring the Factors that Affect Creativity among Adolescents
Authors: Khan Deepanjana , Mandal Swagata
Published: June 2024

Aims: Ideas are the key to innovation. In this competitive era the excellence of the mankind depends on their innovation. Innovative outcomes laid stress on how to think divergently. Creativity is varied in nature. Several factors are responsible to perform any creative task. Therefore, it is necessary to find out the most important factor which can help to expedite creativity among the person, more specifically to explore the scientific reason behind the specific factor and multivariate relationship between two or more factors.
Study Design: In the present study the investigator used explanatory-case study method.
Methodology: The present research included under non-probability sampling technique. For conducting the present research work systematically researcher used purposive sampling method for sample selection. It is basically selected for solving several purposes properly. Therefore the willing and accessible 31 subjects are chosen for this purpose. Out of 31 subjects, 20 students arefrom Bengali Medium School and remaining 11students are from English Medium School. These schools are affiliated to West Bengal Board of Secondary Education and CBSE Board.
Results: A scatter analysis is used to compare two data sets for finding out the relationship between them. Simultaneously, curve fitting algorithm is used to examine the relationship between one or more predictors (independent variable) and a response variable (dependent variable) with the goal of defining a best fit model of the relationship. The major aim of this study is to find out the relationship between one or more predictors (independent variable) and a response variable (dependent variable) with the goal of defining a best fit model of the relationship.
Conclusion: Exploring the effective factors of creativity is addressed on 14 years age of boys and girls.
Edible Coatings: A Novel Approach to Extending the Shelf Life of Fruits and Vegetables
Authors: Rajial Harshit , Varma Suraj
Published: June 2024

The rapid deterioration of fruits and vegetables during pre- and post-harvest conditions leads to significant post-harvest losses, affecting both quality and shelf life. Edible coatings have emerged as an effective solution to mitigate these issues, providing a protective layer that can be safely consumed as part of the food. Recently, there has been growing interest in using herbal extracts such as lemongrass, oregano, Aloe vera, Tulsi, mint, neem, cinnamon, and clove for edible coatings due to their beneficial properties. These herbal-based coatings have been shown to prevent water loss, control the ripening process and respiration rate, delay oxidative browning, and reduce microbial growth in various fruits and vegetables, including grapes, papaya, oranges, cucumbers, tomatoes, apples, and mangoes. Research indicates that these herbal edible coatings can extend the storage time of fresh produce to 15-35 days at low temperatures, compared to the 8-10 days for uncoated produce. The use of herbal extracts in edible coatings is a promising alternative to post-harvest chemical treatments, offering an innovative approach for commercial application. Edible coatings not only extend the post-harvest life of fresh produce but also improve food appearance and safety due to their environmentally friendly nature. They can be derived from animal or vegetable sources and may consist of proteins, lipids, polysaccharides, resins, or combinations thereof. Acting as barriers to moisture and gases, these coatings reduce food deterioration and enhance safety, often incorporating antimicrobial compounds. The advantages of edible coatings include reduced packaging waste, extended shelf life, and protection from environmental effects while maintaining the transfer of oxygen, carbon dioxide, moisture, aroma, and taste. Given the high market demand for nutritious fruits and vegetables and their perishable nature, edible coatings present an effective method to address post-harvest challenges, benefiting both consumers and the environment. This review discusses the components, benefits, and application techniques of edible coatings, focusing on their potential to enhance the shelf life and quality of fresh produce.
Umgehung(sversuche) bei Vorkaufsrechten an Grundstücken
Authors: Grziwotz Herbert
Published: June 2024

Nicht nur bei drohenden Vorkaufsrechten der öffentlichen Hand, sondern auch bei den gesetzlichen Vorkaufsrechten des Mieters und der Miterben sowie ferner bei rechtsgeschäftlich vereinbarten Vorkaufsrechten wird häufig anlässlich der Veräußerung der betroffenen Immobilie gefragt, wie man das Vorkaufsrecht „vermeiden“ oder zumindest seine Ausübung erschweren könne. Der nachfolgende Beitrag stellt die Grenzen für diesbezügliche Gestaltungen anhand der Rechtsprechung dar und kritisiert ihre teilweise ungenügende Umsetzung.
Nonparametric (Distribution‐Free) Quality Control Charts
Authors: Chakraborti Subha
Published: August 2011

Control charts that are typically based on the assumption of a specific form of a parametric distribution, such as the normal, are called parametric control charts. In many applications, however, there is not enough information to justify this assumption and control charts that do not depend on a particular distributional assumption are desirable. Nonparametric or distribution‐free control charts can serve this broader purpose. A key advantage of nonparametric charts is that its in‐control run length distribution is the same for all continuous process distributions. This means, for example, that the false alarm rate and the in‐control average run length of a nonparametric chart is the same for all continuous distributions. This is not true for parametric control charts in general and consequently their in‐control robustness can be a legitimate concern. Nonparametric charts are often more robust and efficient than their normal theory counterparts under heavy‐tailed and/or asymmetric distributions. In this paper we discuss developments, mostly in the area of univariate nonparametric control charts; this includes cases when the underlying parameters are specified as well as when they are unknown and are therefore estimated from the data. The majority of the charts are for monitoring the location; few charts are available for scale.
Optimal Sample Size Allocation for Accelerated Degradation Test Based on Wiener Process
Authors: Tseng Sheng‐Tsaing , Tsai Chih‐Chun , Balakrishnan N.
Published: August 2011

Degradation tests are widely used to assess the reliability of highly reliable products which are not likely to fail under traditional life tests or accelerated life tests (ALT). However, for some highly reliable products, the degradation may be very slow, and thus it seems impossible to have a precise assessment within a reasonable test time. In such cases, an alternative technique is to use higher stresses to extrapolate the product's reliability at the normal use stress. This is called an accelerated degradation test (ADT). In this article, motivated by a LEDs data, we discuss the optimal allocation problem under accelerated degradation experiment when a Wiener process is used to describe the product's degradation path. We derive the Fisher information and the approximate variance of the estimated mean‐time‐to‐failure (MTTF) under normal use. Three optimality criteria are defined and the optimal allocation of test units are determined. Finally, the LEDs data is illustrated to demonstrate the efficiency of the optimal allocation of test units.
Structural Results forPOMDPs
Authors: Zheltova Ludmila V.
Published: August 2011

Partially observable Markov decision processes (POMDP) are used to describe stochastic systems with incomplete information about the state of the system. Owing to the complexity of POMDP analysis, a primary goal is to identify conditions under which the optimal policy has a structure that is simple to implement.A prioriknowledge of policy structure makes its computation, communication, and implementation fast and effective. This article discusses the optimal policy structures for the general POMDP model and provides examples of such structures in the context of maintenance optimization. A brief overview of the research results concerning policy structures in different application areas is provided.
The Canadian Operational Research Society/Société Canadienne De Recherche Opérationelle
Authors: Caron Richard J. , Ingolfsson Armann , Quan Vinh
Published: August 2011

Founded in 1958 and incorporated on 25 February 1964, the Canadian Operational Research Society (CORS) takes a leadership role in the advancement of both the theory and practice of operational research (OR) in Canada, and it represents the Canadian OR community in the International Federation of Operational Research Societies (IFORS). We meet our objectives with our publications, Web site (
www.cors.ca
), and annual conference and by supporting a diverse array of local section activities. The society is bilingual and is also known as the Société canadienne de recherche opérationelle (SCRO).
Compounds of Selenium and Tellurium with Nitrogen Bonds
Authors: M. Klapötke Thomas , Krumm Burkhard , Moll Richard
Published: August 2011

In the last three decades the field of the traditionally more exotic selenium nitrogen and tellurium nitrogen compounds has developed considerably. This review presents some of the recent results with a focus on crystal structures. The application of nitrogen NMR spectroscopy will be illustrated as an additional useful tool for the characterization of SeN and TeN materials. This chapter includes newer results on binary, ternary, organoselenium and organotellurium amides, imides, azides and other classes of compounds divided into the different oxidation states of selenium and tellurium. Furthermore, the latest selenium and tellurium nitrogen‐containing carbocycles will be mentioned.
Selenium and Tellurium (1,2,3)‐Oxygen‐containing Acids and Derivatives
Authors: Drabowicz Józef , Dorota Krasowska Wanda Halina Midura
Published: August 2011

The chapter presents the advances in the chemistry of oxoacids of selenium and tellurium and their derivatives, which have emerged in recent years (mostly after 1998) based on the division of the discussed compounds into particular subclasses arising from the oxidation state of a central chalcogen atom. It begins with a brief discussion on the nature of bonding between the chalcogen and oxygen atoms. Next this chapter presents for the first time all the available data on basic synthetic protocols leading to alkane (arene) oxoacids of selenium and tellurium, and the acid halides, esters and amides derived from them. A brief discussion on their structure and reactivity is also included. The derivatives are presented in the following order: (a) divalent, dicoordinated selenenic and tellurenic acids, RChOH (ChSe or Te), and their derivatives; (b) tetravalent, tricoordinated seleninic and tellurinic acids, RCh(O)OH, and their derivatives RCh(O)L (ChSe or Te; LX, OR, NR1R2); (c) hexavalent, tetraacoordinated selenonic and telluronic acids, RCh(O)2OH, and their derivatives RCh(O)2L (ChSe or Te; LX, OR, NR1R2).
A Study of Twin Variant Selection and Twin Growth in Titanium
Authors: Bao Lei , Schuman Christophe , Lecomte Jean‐Sébastien , Philippe Marie‐Jeanne , Zhao Xiang , Esling Claude
Published: August 2011

An in depth analysis on twin variant selection and twin growth character during compression by means of “interrupted in situ” EBSD orientation measurement was carried out. An experimental verification and geometrical analysis of the use of Schmid's law as a criterion for selecting twin variants was performed, and proved to be conclusive. Twin variants having Schmid factors higher than 0.4 have a good chance to be activated. The twin growth exhibits two modes: {11–22} twins show a tendency to multiple variants system (MVS) and {10–12} twins show predominant variant system (PVS). The Schmid factor plays an important role in MVS and PVS.
Cancer Nanotheranostics: Improving Imaging and Therapy by Targeted Delivery Across Biological Barriers
Authors: Kievit Forrest M. , Zhang Miqin
Published: August 2011

Cancer nanotheranostics aims to combine imaging and therapy of cancer through use of nanotechnology. The ability to engineer nanomaterials to interact with cancer cells at the molecular level can significantly improve the effectiveness and specificity of therapy to cancers that are currently difficult to treat. In particular, metastatic cancers, drug‐resistant cancers, and cancer stem cells impose the greatest therapeutic challenge for targeted therapy. Targeted therapy can be achieved with appropriately designed drug delivery vehicles such as nanoparticles, adult stem cells, or T cells in immunotherapy. In this article, we first review the different types of nanotheranostic particles and their use in imaging, followed by the biological barriers they must bypass to reach the target cancer cells, including the blood, liver, kidneys, spleen, and particularly the blood‐brain barrier. We then review how nanotheranostics can be used to improve targeted delivery and treatment of cancer cells. Finally, we discuss development of nanoparticles to overcome current limitations in cancer therapy.
An ontology‐based mechanism for automatic categorization of web services
Authors: Kehagias Dionysios D. , Giannoutakis Konstantinos M. , Gravvanis George A. , Tzovaras Dimitrios
Published: August 2011

The addition of semantic information into Web services (WS) results in more accurate search and retrieval in service registries. The key issue to facilitate organization of services, taking into account their semantics, is the development of automatic mechanisms that generate appropriate mappings between Web service elements and their semantics‐enabled counterparts. In this paper, we introduce an ontology‐based mechanism for automatic semantic categorization of WS and their structural components. The presented approach, as opposed to similar ones, takes into account the lexicographic, structural, and data type characteristics of WS. Moreover, a software tool that implements the proposed service categorization mechanism is presented, and a benchmark process is executed that reveals outstanding performance of the developed mechanism in comparison with a relevant state‐of‐the‐art approach. Copyright © 2011 John Wiley & Sons, Ltd.
LFTM, linguistic fuzzy trust mechanism for distributed networks
Authors: Gómez Mármol Félix , Marín‐Blázquez Javier G. , Martínez Pérez Gregorio
Published: August 2011

Trust is, in some cases, being considered as a requirement in highly distributed communication scenarios. Before accessing a particular service, a trust model is then being used in these scenarios to determine if the service provider can be trusted or not. It is done usually on behalf of the final user or service customer, and with a little intervention of him or her. This is usually happening with the main aim of automatizing the process and because trust models are normally making use of reasoning mechanisms and models difficult to understand by humans. In this paper, we propose the adaptation of a bio‐inspired trust model to deal with linguistic fuzzy labels, which are closer to the human way of thinking. This Linguistic Fuzzy Trust Model also uses fuzzy reasoning. Results show that the new model keeps the accuracy of the underlying bio‐inspired trust model and the level of client satisfaction, while enhancing the interpretability of the model and thus making it closer to the final user. Copyright © 2011 John Wiley & Sons, Ltd.
Trusted information exchange in peer‐to‐peer mobile social networks
Authors: Qureshi Basit , Min Geyong , Kouvatsos Demetres
Published: August 2011

Social networks have recently been gaining popularity. In a peer‐to‐peer mobile social network (MSN), users with similar interests establish groups or communities and share information without relying on a centralized infrastructure. Users socially interact with each other using handheld mobile devices and membership in a group/community of MSNs is granted by a pre‐existing group member. However, it is possible that a group of malicious users can collude to promote another untrustworthy user in becoming a group member. Moreover, revoking membership without the existence of a central authority in a group is also a grant challenge. To address these problems in peer‐to‐peer MSNs, we propose a decentralized framework and the related algorithms for trusted information exchange and social interaction among users based on the dynamicity aware graph relabeling system. In contrast to the existing implementations of social networks based on a client/server paradigm, the proposed framework utilizes a lightweight trust model for identifying trustworthy users and aims at creating communities of trusted users while isolating and reducing interactions with untrustworthy users. Simulation results demonstrated the effectiveness of the proposed framework compared with the traditional dynamicity aware graph relabeling system algorithm.Copyright © 2011 John Wiley & Sons, Ltd.
Experimental and numerical study of burning behaviors of flaxboard with intumescent coating and nanoparticles in the cone calorimeter and single burning item tests
Authors: Zhang Jianping , Delichatsios Michael A. , McKee Maurice , Ukleja Sebastian
Published: August 2011

This paper presents an experimental and numerical investigation of the effects of intumescent coating and nanoparticles on the burning behaviors of flaxboard. Virgin flaxboard samples and those coated with intumescent coatings (with/without nanoparticles) were tested in the cone calorimeter and single burning item (SBI) test. Experimental results show a significant increase in the time to ignition and also a reduction in the heat release rate by the intumescent coatings. In order to explain quantitatively and predict the effects of the intumescent coating, a global fractional factor (the ratio of the heat flux at the interface of the intumescent surface and the char layer of flaxboard to the surface heat flux when there is no intumescent coating layer) was introduced based on analytical solutions for charring materials. The fractional factor for the intumescent coatings was found by comparing predictions to the experimental data in the cone calorimeter test and, subsequently, was incorporated in an upward flame spread model, along with the ignition and thermal properties deduced from the ignition tests, to predict the burning rates in the SBI tests. Copyright © 2011 John Wiley & Sons, Ltd.
In vivo measurement of bladder wall oxygen saturation using optical spectroscopy
Authors: Amelink Arjen , Kok Dirk J. , Sterenborg Henricus J. C. M. , Scheepe Jeroen R.
Published: August 2011

Current diagnosis, follow‐up and treatment of patients suffering from bladder dysfunction are mainly symptom‐targeted. A recently recognized cause of continuing bladder function loss is a deteriorated bladder microvasculature. Incorporating this aspect into the clinical diagnostic toolbox may improve treatment results. Recent developments in the field of optical spectroscopy now allow for non‐invasive measurement of microvascular blood oxygen saturation in living tissue. We have recently reported pre‐clinical data that show that this marker can be successfully measured in an animal bladder. In the animal model the marker differentiated bladders with loss of function from those with normal function. In the present paper, we report on the first in vivo measurement of this marker in the human bladder, as proof of principle, in the muscle of bladders with a normal function. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Monitoring blood volume and saturation using superficial fibre optic reflectance spectroscopy during PDT of actinic keratosis
Authors: Middelburg Tom A. , Kanick Stephen C. , de Haas Ellen R. M. , Sterenborg Henricus J. C. M. , Amelink Arjen , Neumann Martino H. A. M. , Robinson Dominic J.
Published: August 2011

Optically monitoring the vascular physiology during photodynamic therapy (PDT) may help understand patient‐specific treatment outcome. However, diffuse optical techniques have failed to observe changes herein, probably by optically sampling too deep. Therefore, we investigated using differential path‐length spectroscopy (DPS) to obtain superficial measurements of vascular physiology in actinic keratosis (AK) skin. The AK‐specific DPS interrogation depth was chosen up to 400 microns in depth, based on the thickness of AK histology samples. During light fractionated aminolevulinic acid‐PDT, reflectance spectra were analyzed to yield quantitative estimates of blood volume and saturation. Blood volume showed significant lesion‐specific changes during PDT without a general trend for all lesions and saturation remained high during PDT. This study shows that DPS allows optically monitoring the superficial blood volume and saturation during skin PDT. The patient‐specific variability supports the need for dosimetric measurements. In DPS, the lesion‐specific optimal interrogation depth can be varied based on lesion thickness. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Intense tropical cyclone activities in the northern Indian Ocean
Authors: Hoarau Karl , Bernard Julien , Chalonge Ludovic
Published: August 2011

This research concerning the northern Indian Ocean demonstrates the variability of intense tropical cyclones (categories 3–5) both on an inter‐annual and intra‐seasonal scale. All the cyclones intensity have been re‐analysed with the Dvorak technique using both National Oceanic and Atmospheric Administration and geostationary satellites with a 4‐km infrared resolution. During the period from 1980 to 2009, 21 cyclones became intense. The decade from 1990 to 1999 was by far the most active with 11 intense cyclones while 5 intense cyclones formed in each of the other two decades. There has been no trend towards an increase in the number of categories 3–5 cyclones over the last 30 years. An early study, not based on re‐analysed data, found a significant increase in the number of intense cyclones. Thirteen cyclones became intense when the Oceanic Nino Index was negative and matched with lower vertical wind shear. And, La Nina events have had a noticeable influence with eight intense cyclones. The monthly distribution is bimodal with seven and eight cyclones, respectively in the months of May and November. No intense cyclones were observed from July to September, being the peak of the monsoon season. Over these 3 months, the vertical wind shear is too strong to allow a significant intensification of storms. Despite particularly warm ocean waters, only 6% of categories 1–5 cyclones approached their maximum potential intensity. However, extreme intensities (05B at 155 knots in 1999) are comparable to other basins despite lower in terms of activity level. The proximity of land limits most cyclones from reaching a greater intensity. However, 16 of the 21 cyclones reached land with sustained winds of 100 knots and more. India and Bangladesh have been hit frequently by intense cyclones. Since 1990s, there is an increasing hit in Burma and Pakistan. Copyright © 2011 Royal Meteorological Society
APPRAISAL OF SOIL EROSION RISK IN THE EASTERN HIMALAYAN REGION OF INDIA FOR SOIL CONSERVATION PLANNING
Authors: Mandal D. , Sharda V. N.
Published: August 2011

Management practices to minimise soil erosion can be effectively carried out if the magnitude and the spatial distribution of soil erosion risk areas are known. Prioritisation of soil erosion risk areas is a challenging task, especially in the developing countries because of non‐availability of relevant data and analytical tools for such an assessment. As a result, it becomes difficult to establish appropriate soil conservation measures on the risk‐prone areas to reduce soil loss and ensure development of a sustainable management of soil resources. Such a database can be better generated and analysed in a geographical information system (GIS) environment to delineate and prioritise the soil erosion risk areas at state or regional level. Therefore, a methodology was developed to assess the soil erosion risks in eastern Himalayan region by integrating spatial data on prevailing erosion rates and soil loss tolerance limits in GIS environment. By comparing the potential erosion rates with permissible rates, we observed that about 58·94 per cent of total geographical area (TGA) of the region requires different degrees of erosion management and 28·38 per cent of TGA falls under no treatment category because of higher values of permissible erosion limits. It can be successfully applied to assess and prioritise soil erosion risks in any region or country and identify best management practices to bring the erosion losses within the permissible limits. Copyright © 2011 John Wiley & Sons, Ltd.
Cultural Patterns Influencing Project Team Behavior in Sub-Saharan Africa: A Case Study in Ethiopia
Authors: Jetu Fanta Tesgera , Riedl René , Roithmayr Friedrich
Published: August 2011

Despite the increasing attention paid to the human element of project success found in the project management literature, empirical studies exploring cultural patterns influencing this particular human element continue to be far from satisfactory. To help further understand the influence of cultural patterns within Sub-Saharan Africa project environments, we draw on a case study conducted in Ethiopia's service sector. Apart from the well-perceived cultural values commonly referred to in the existing literature, we specifically investigated the deep-rooted underlying causes, which include Ethiopian cultural habits, as a principal factor in influencing project team behavior. The article concludes with implications and recommendations for future research.
Mechanical and electron‐transport properties of graphene nanoribbons under tensile strain: A first‐principles study
Authors: Yu Shan‐Sheng , Wang Chun , Zheng Wei‐Tao , Jiang Qing
Published: August 2011

We calculate the mechanical and electron‐transport properties of graphene nanoribbons (GNRs) under uniaxial tensile strain with first‐principles density functional theory. Our calculations reveal that armchair‐ and zigzag‐shaped edges decrease and increase the tensile strength of GNR, respectively. The I–V curve for GNR with armchair edges changes drastically under tensile strain, while the influence of tensile strain on the electron‐transport properties of GNR with zigzag edges is negligible. Our calculations propose one way to design and fabricate nanoscale mechanical sensors and devices based on GNRs.
A study of the luminescence and energy transfer in Ba1.6Ca0.4P2O7 codoped with Eu2+ and Mn2+
Authors: Zhang Xin‐min , Li Wen‐lan , Seo Hyo Jin
Published: August 2011

Eu2+,Mn2+‐doped phosphors in the novel system Ba1.6Ca0.4P2O7 were prepared by solid‐state reactions. The photoluminescence (PL) properties of Eu2+,Mn2+ in Ba1.6Ca0.4P2O7 are reported and discussed. The emission spectrum of Ba1.6Ca0.4P2O7:0.04Eu2+ consists of two distinct broad bands peaking at about 400 and 470 nm, and the excitation spectra exhibit broad band in the range of 250–400 nm. A broad yellow emission band is observed around 565 nm in a Mn2+ single‐doped sample, and the intensity can be enhanced by codoping with Eu2+ ions. Evidence is presented for the energy transfer from Eu2+ to Mn2+ in this host lattice.
Effect of an external magnetic field on the morphology and magnetic properties of CoFe nanostructures
Authors: Rajan Ganesh. K. , Ramaswamy Shivaraman , Gopalakrishnan C. , Thiruvadigal D. John
Published: August 2011

The effect of an external magnetic field with a flux density of 0.2 T and different configurations relative to the plane of the sample (normal‐to and in‐plane) on the nucleation and growth of CoFe nanostructures has been investigated. CoFe nanostructures were grown on N‐type Si (111) substrate using an e‐beam evaporation system. The samples were subjected to an external magnetic field of 2 T normal‐to and in‐plane to the plane of the samples during the growth period. The influence of the magnetic field on the morphology of the CoFe nanostructures was studied using atomic force microscopy and scanning electron microscopy. Significant changes in the structural characteristics due to the influence of the magnetic fields were evident. Further, the influence of the external magnetic field on the magnetic properties of the materials was analyzed using a vibrating sample magnetometer (VSM) and the composition of the samples was analyzed using energy dispersive X‐ray spectrometry. These results indicate that the easy axis of magnetization in both the samples (normal‐to and in‐plane) is along the direction of the applied magnetic field.
Pressure and temperature dependence of gain in InGaAs/GaAs laser diode
Authors: Bajda Monika , Piechal Bernard , Dybała Filip , Bercha Artem , Trzeciakowski Witold , Majewski Jacek A.
Published: August 2011

Wavelength dependent gain has been calculated for InGaAs/GaAs quantum‐well (QW) lasers as a function of hydrostatic pressure and temperature. The shift of the gain maximum for such laser is equal to −140 nm by increasing the pressure up to 20 kbar and −60 nm by cooling down from 300 to 100 K. The width of the gain curve (determining the possible tuning range with external grating) is significantly reduced at low temperatures and (to a lower extent) at high pressures. Our results indicate that pressure tuning is much more effective than temperature tuning when combined with tuning by external grating.
Low‐temperature growth of multi‐walled carbon nanotubes by thermal CVD
Authors: Halonen Niina , Sápi András , Nagy László , Puskás Róbert , Leino Anne‐Riikka , Mäklin Jani , Kukkola Jarmo , Tóth Geza , Wu Ming‐Chung , Liao Hsueh‐Chung , Su Wei‐Fang , Shchukarev Andrey , Mikkola Jyri‐Pekka , Kukovecz Ákos , Kónya Zoltán , Kordás Krisztián
Published: August 2011

Low‐temperature thermal chemical vapor deposition (thermal CVD) synthesis of multi‐walled carbon nanotubes (MWCNTs) was studied using a large variety of different precursor compounds. Cyclopentene oxide, tetrahydrofuran, methanol, and xylene:methanol mixture as oxygen containing heteroatomic precursors, while xylene and acetylene as conventional hydrocarbon feedstocks were applied in the experiments. The catalytic activity of Co, Fe, Ni, and their bi‐ as well as tri‐metallic combinations were tested for the reactions. Low‐temperature CNT growth occurred at 400 °C when using bi‐metallic Co–Fe and tri‐metallic Ni–Co–Fe catalyst (on alumina) and methanol or acetylene as precursors. In the case of monometallic catalyst nanoparticles, only Co (both on alumina and on silica) was found to be active in the low temperature growth (below 500 °C) from oxygenates such as cyclopentene oxide and methanol. The structure and composition of the achieved MWCNTs products were studied by scanning and transmission electron microscopy (SEM and TEM) as well as by Raman and X‐ray photoelectron spectroscopy (XPS) and by X‐ray diffraction (XRD). The successful MWCNT growth below 500 °C is promising from the point of view of integrating MWCNT materials into existing IC fabrication technologies.
EPR study of conduction electrons in heavily doped n‐type 4H SiC
Authors: Savchenko Dariya V. , Kalabukhova Ekaterina N. , Pöppl Andreas , Mokhov Evgenij N. , Shanina Bela D.
Published: August 2011

The magnetic properties of conduction electrons (CE) in heavily doped n‐type 4H SiC have been studied with electron paramagnetic resonance (EPR) in the temperature interval from 7 to 140 K. An EPR line with “Dyson lineshape” was observed in 4H SiC wafers with (ND–NA) ≈ 1019 cm−3. The EPR line is composed of two overlapping lines with Lorentzian and Dysonian lineshape, which are responsible for the localized and delocalized spin systems attributed to electrons localized on the nitrogen donors (LE) and CE, respectively. The Dysonian line is characterized by an asymmetry parameter R. The coupling between the two spin systems, which are characterized by S = 1/2 is realized via an exchange interaction of CE with the LE. As a result the g‐factor of the Dysonian spectral line is governed by an exchange interaction between LE and CE and was evaluated as g|| = 2.0045, g⟂ = 2.0003. The temperature dependence of the integral intensity of the CE EPR signal is described by the sum of Curie–Weiss and Pauli paramagnetism. The Curie‐like contribution arises from unpaired spins in the impurity band of heavily doped 4H SiC, while a Pauli‐like contribution that becomes noticeable at T > 80 K indicates the presence of the CE in the conduction band. From the analysis of the temperature dependence of R(T) and the linewidth ΔH(T) of the CE EPR signal the activation energy of the CE into the conduction band was estimated to be 39.4 meV. The obtained value of the activation energy coincides with that for nitrogen donors forming an impurity band in heavily doped n‐type 4H SiC. Thus, the temperature behavior of the CE spin system in highly doped 4H SiC can be interpreted in terms of electrons that are freely moving over the impurity and conduction band. The CE present in the impurity band are strongly coupled with LE by cross‐relaxation processes.
Aloe Vera Juice: IC50 and Dual Mechanistic Inhibition of CYP3A4 and CYP2D6
Authors: Djuv Ane , Nilsen Odd Georg
Published: August 2011

The aim of this study was to evaluate the inhibitory potency (IC50 values) of ethanol extracts of two commercially available aloe vera juice (AVJ) products, on CYP3A4 and CYP2D6 activities in vitro and to determine if such inhibitions could be mechanism‐based. Recombinant human CYP3A4 and CYP2D6 enzymes were used and the activities were expressed by the metabolism of testosterone and dextromethorphan with ketoconazole and quinidine as positive inhibitor controls, respectively. The formed metabolites were quantified by validated HPLC techniques. Time‐ and NADPH‐ dependent inhibition assays were performed to evaluate a possible mechanism‐based inhibition. One of the AVJ extracts showed about twice the inhibitory potency towards both CYP enzymes over the other with IC50 values of 8.35 ± 0.72 and 12.5 ± 2.1 mg/mL for CYP3A4 and CYP2D6, respectively. The AVJ was found to exert both CYP mediated and non‐CYP mediated inhibition of both CYP3A4 and CYP2D6. This dual mechanistic inhibition, however, seems to be governed by different mechanisms for CYP3A4 and CYP2D6. Estimated IC50 inhibition values indicate no major interference of AVJ with drug metabolism in man, but the dual mechanistic inhibition of both enzymes might be of clinical significance. Copyright © 2011 John Wiley & Sons, Ltd.
Real‐Time Template‐Assisted Manipulation of Nanoparticles in a Multilayer Nanofluidic Chip
Authors: Chen H. Matthew , Pang Lin , Gordon Michael S. , Fainman Yeshaiahu
Published: August 2011

The ability to control dynamically the flow and placement of nanoscale particles and biomolecules in a biocompatible, aqueous environment will have profound impact in advancing the fields of nanoplasmonics, nanophotonics, and medicine. Here, an approach based on electrokinetic forces is demonstrated that enables dynamically controlled placement of nanoparticles into a predefined pattern. The technique uses an applied voltage to manipulate nanoparticles in a multilayer nanofluidic chip architecture. Simulations of the nanoparticles' motion in the nanofluidic chip validate the approach and are confirmed by experimental demonstration to produce uniform 200‐nm‐diameter spherical nanoparticle arrays. The results are important as they provide a new method that is capable of dynamically capturing and releasing nanoscale particles and biomolecules in an aqueous environment, which could lead to the creation of reconfigurable nanostructure patterns for nanoplasmonic, nanophotonic, biological sensing, and drug‐delivery applications.
Entire network load‐aware cooperative routing algorithm for video streaming over mobile ad hoc networks
Authors: Kwon Oh Chan , Oh Hyung Rai , Lee Zae‐Kwun , Lee GyeongCheol , Park Youngho , Song Hwangjun
Published: August 2011

In this paper, we present an entire network load‐aware cooperative routing algorithm based on IEEE 802.11 multi‐rate for video streaming over mobile ad hoc networks. The proposed routing algorithm is designed to minimize the consumed time slots while guaranteeing the required time slots at all the pairs of adjacent nodes over the route and the contention neighbors of these nodes to support the route. Furthermore, the proposed routing algorithm can distribute the network loads well over the entire network. This technology is essential because video streaming applications require stringent quality of service and even larger network resources compared with traditional data services, and these demands may dramatically increase the entire network load and/or cause network congestion. Finally, experimental results are provided to show a performance of the proposed routing algorithm. Copyright © 2011 John Wiley & Sons, Ltd.
A pilot‐aided detector for spectrum sensing of Digital Video Broadcasting—Terrestrial signals in cognitive radio networks
Authors: Yin Wenshan , Ren Pinyi , Cai Jun , Su Zhou
Published: August 2011

In this paper, the main properties of digital television broadcasting signals based on the Digital Video Broadcasting—Terrestrial (DVB‐T) standard are analyzed, and these properties are utilized to design a new pilot‐aided detector for spectrum sensing in cognitive radio networks. The proposed detector consists of a processing unit and a combination and decision unit. In the processing unit, multiple statistics that correspond to different enhanced pilot components are computed. In the combination and decision unit, three newly proposed combination schemes are adopted to combine these statistics, and then, a final decision on the presence or absence of the DVB‐T signals is made on the basis of the Neyman–Pearson criterion. The proposed pilot‐aided detector exploits both the periodic continual and scattered pilots that are intrinsic in the DVB‐T signals, processes the observed data timely, experiences short sensing duration, and requires no time synchronization information. Furthermore, the proposed pilot‐aided detector is able to distinguish DVB‐T signals from interference. Theoretical analysis and simulation results show that spectrum bands that are not currently occupied by the DVB‐T systems can be detected accurately by using the proposed pilot‐aided detector. Simulation results also demonstrate the significant performance gain of the proposed detector compared with the counterparts.Copyright © 2011 John Wiley & Sons, Ltd.
Weighted partial network coding and its applications in wireless mesh networks
Authors: Chen Fajun , Wang Yijie , Wang Dan , Liu Jiangchuan
Published: August 2011

Network coding (NC) has showed to be beneficial to improve transmission performance in wireless mesh networks. Random linear coding is usually applied as the default coding schema. However, random linear coding causes significant decoding delay and jitter at receiver. Further, current NC does not support weight assignment to original packets, which is however indispensable for popular applications such as quality of service control and multipath media streaming in wireless mesh networks. Partial network coding (PNC) can largely reduce decoding delay and receiving fluctuation while keeping the benefit of NC. However, PNC does not support weight‐based data replacement and weight assignment to original packets. In this work, we propose weighted partial network coding (WPNC), which is a generalized coding schema of PNC. WPNC inherits all merits of PNC and part of NC. With WPNC, both decoding delay and receiving fluctuation will be reduced as observed in PNC. Also, WPNC is quite suitable for those applications that require weight assignment to original packets. After providing the whole framework of WPNC and thorough theoretical analysis to its performance, we have demonstrated how WPNC can be integrated with quality of service control and multipath routing supported media streaming in wireless mesh networks. Performance of WPNC is inter‐validated by both theoretical analysis and numeric evaluations. Copyright © 2011 John; Wiley & Sons, Ltd.