A Security Pattern for Cloud service certification

Cloud computing is interesting from the economic, operational and even energy consumption perspectives but it still raises concerns regarding the security, privacy, governance and compliance of the data and software services offered through it. However, the task of verifying security properties in services running on cloud is not trivial. We notice the provision and security of a cloud service is sensitive. Because of the potential interference between the features and behavior of all the inter-dependent services in all layers of the cloud stack (as well as dynamic changes in them). Besides current cloud models do not include support for trust-focused communication between layers. We present a mechanism to implement cloud service certification process based on the usage of Trusted Computing technology, by means of its Trusted Computing Platform (TPM) implementation of its architecture. Among many security security features it is a tamper proof resistance built in device and provides a root of trust to affix our certification mechanism. We present as a security pattern the approach for service certification based on the use TPM.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Estimating Footfall From Passive Wi-Fi Signals: Case Study with Smart Street Sensor Project

Measuring the distribution and dynamics of the population at granular level both spatially and temporally is crucial for understanding the structure and function of the built environment. In this era of big data, there have been numerous attempts to undertake this using the preponderance of unstructured, passive and incidental digital data which are generated from day-to-day human activities. In attempts to collect, analyse and link these widely available datasets at a massive scale, it is easy to put the privacy of the study subjects at risk. This research looks at one such data source - Wi-Fi probe requests generated by mobile devices - in detail, and processes it into granular, long-term information on number of people on the retail high streets of the United Kingdom (UK). Though this is not the first study to use this data source, the thesis specifically targets and tackles the uncertainties introduced in recent years by the implementation of features designed to protect the privacy of the users of Wi-Fi enabled mobile devices. This research starts with the design and implementation of multiple experiments to examine Wi-Fi probe requests in detail, then later describes the development of a data collection methodology to collect multiple sets of probe requests at locations across London. The thesis also details the uses of these datasets, along with the massive dataset generated by the ‘Smart Street Sensor’ project, to devise novel data cleaning and processing methodologies which result in the generation of a high quality dataset which describes the volume of people on UK retail high streets with a granularity of 5 minute intervals since August 2015 across 1000 locations (approx.) in 115 towns. This thesis also describes the compilation of a bespoke ‘Medium data toolkit’ for processing Wi-Fi probe requests (or indeed any other data with a similar size and complexity). Finally, the thesis demonstrates the value and possible applications of such footfall information through a series of case studies. By successfully avoiding the use of any personally identifiable information, the research undertaken for this thesis also demonstrates that it is feasible to prioritise the privacy of users while still deriving detailed and meaningful insights from the data generated by the users

Unmanned Aerial Vehicle (UAV)-Enabled Wireless Communications and Networking

The emerging massive density of human-held and machine-type nodes implies larger traffic deviatiolns in the future than we are facing today. In the future, the network will be characterized by a high degree of flexibility, allowing it to adapt smoothly, autonomously, and efficiently to the quickly changing traffic demands both in time and space. This flexibility cannot be achieved when the network’s infrastructure remains static. To this end, the topic of UAVs (unmanned aerial vehicles) have enabled wireless communications, and networking has received increased attention. As mentioned above, the network must serve a massive density of nodes that can be either human-held (user devices) or machine-type nodes (sensors). If we wish to properly serve these nodes and optimize their data, a proper wireless connection is fundamental. This can be achieved by using UAV-enabled communication and networks. This Special Issue addresses the many existing issues that still exist to allow UAV-enabled wireless communications and networking to be properly rolled out

Codifying Contract Law in Australia: Issues and Obstacles

In March 2012, the Commonwealth Attorney-General’s Department issued a brief but wide-ranging discussion paper which explored the possibility of codifying or otherwise significantly reforming Australian contract law. Though the 2012 Discussion Paper attracted 58 insightful and closely-argued submissions along with a number of thoughtful papers, there nonetheless remains a clear disjunct between the significance and scope of the questions raised by the discussion paper and the response which it attracted. Indeed, though the notion of codifying Australian contract law has been mooted several times in the past fifty years, the merit of such a reform has rarely been the subject of sustained and detailed analysis. This thesis seeks to go some way towards filling this gap. It grapples with a wide range of important issues thrown up by the question of whether the Australian law of contract ought to be codified, with the aim of arriving at a concluded view as to whether that significant step ought to be taken. It shows that there are strong reasons to conclude that the Australian law of contract ought not to be codified. It shows that many of the traditional arguments proffered in favour of the codification of Australian contract law – including the notion that such a reform would promote ‘certainty’ in the law and amount to an ideal mechanism for substantive law reform – begin to break down upon sustained scrutiny. It further shows that there are a number of serious cultural, practical, and theoretical hurdles which would have to be overcome if codification were to be successful. These hurdles are all the more imposing for having been paid too little attention by the proponents of reform. The result is that, in addition to the serious difficulties which attend the positive case for codification, there is also a strong negative case which has received too little serious attention.Thesis (Ph.D.) -- University of Adelaide, Adelaide Law School, 201

Small cells deployment for traffic handling in centralized heterogeneous network

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonAs the next phase of mobile technology, 5G is coming with a new vision that is characterized by a connected society, in which everything will be effectively connected, providing a variety of services and diverse business models that require more than just higher data rates and more capacity to target new kinds of ultra-reliable and flexible connection. However, next generation of applications, services and use cases will have extreme variation in requirements which in turn amplified the demand on the network resources. Therefore, 5G will require a whole new design that take into consideration efficient resource management and utilisation. An observation that was made throughout this research refers to the demand for more capacity, reduced latency, and increased density as common factors of many of the next generation use cases. This inescapably implies that the use of small cells is an ideal solution for next generation applications requirements, provided that the necessary storage and computing resources need to be distributed closer to the actual user. In this context, this research proposed an architecture of a centralised heterogenous network, consisting of Macro and Small cells with storage and computing resources, all controlled by a centralized functionality embedded within a gateway at the edge of the network. Compared to the basic network, the proposed solutions have been proven to provide overall system performance enhancement. This involves extending the system by adding small cells to serve dedicated services for User Equipment (UE) with dual connectivity from local server which reduces the overall system delay while increasing the overall system throughput. The added centralized mobility management was proven to be capable of tracing the mobility of the UEs within the system coverage, by keeping one connection with the main cell while moving between small cells resulting in enhancement to the handover delay by 11% without service interruptions. Finally, the proposed slicing model demonstrated the system’s ability to provide different levels of services to users based on different Quality of Service (QoS) requirements and to differentiate between various applications without affecting the performance of other services, benefiting from more flexible infrastructure than the traditional network. In addition, a 50% improvement in the performance was observed in terms of the CPU utilization. In such architecture, the required capacity can be added exactly where it is needed and when it is needed, coverage problems can be directly addressed, higher throughput, lower latency, and efficient mobility management can be achieved as a result of efficient resource management and distribution which is one of key factors in the deployment of next generation mobile network system

Wireless indoor localisation within the 5G internet of radio light

This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University LondonNumerous applications can be enhanced by accurate and efficient indoor localisation using wireless sensor networks, however trade-offs often exist between these two parameters. In this thesis, realworld and simulation data is used to examine the hybrid millimeter wave and Visible Light Communications (VLC) architecture of the 5G Internet of Radio Light (IoRL) Horizon 2020 project. Consequently, relevant localisation challenges within Visible Light Positioning (VLP) and asynchronous sampling networks are identified, and more accurate and efficient solutions are developed. Currently, VLP relies strongly on the assumed Lambertian properties of light sources. However, in practice, not all lights are Lambertian. To support the widespread deployment of VLC technology in numerous environments, measurements from non-Lambertian sources are analysed to provide new insights into the limitations of existing VLP techniques. Subsequently, a novel VLP calibration technique is proposed, and results indicate a 59% accuracy improvement against existing methods. This solution enables high accuracy centimetre level VLP to be achieved with non- Lambertian sources. Asynchronous sampling of range-based measurements is known to impact localisation performance negatively. Various Asynchronous Sampling Localisation Techniques (ASLT) exist to mitigate these effects. While effective at improving positioning performance, the exact suitability of such solutions is not evident due to their additional processes, subsequent complexity, and increased costs. As such, extensive simulations are conducted to study the effectiveness of ASLT under variable sampling latencies, sensor measurement noise, and target trajectories. Findings highlight the computational demand of existing ASLT and motivate the development of a novel solution. The proposed Kalman Extrapolated Least Squares (KELS) method achieves optimal localisation performance with a significant energy reduction of over 50% when compared to current leading ASLT. The work in this thesis demonstrates both the capability for high performance VLP from non- Lambertian sources as well as the potential for energy efficient localisation for sequentially sampled range measurements.Horizon 202

Encriptación sobre Capa Física para Ethernet Óptico de Alta Velocidad

INTRODUCCIÓN-------------------------Hoy en día, los enlaces ópticos con tasas de transmisión de hasta 100 Gbps y superiores son ya una realidad. Gracias a los avances logrados en las comunicaciones ópticas durante las últimas décadas es posible afrontar anchos de banda cada vez mayores, lo que satisface las demandas de las aplicaciones más exigentes [CIS16], como por ejemplo las basadas en cloud computing o big data. Por otro lado, la seguridad en la información sigue siendo un asunto de gran importancia en las comunicaciones ya que el volumen de amenazas en la red se ha incrementado durante los últimos años [CIS18]. Los fallos en la seguridad podrían llevar al mal funcionamiento de un servicio o la pérdida de confidencialidad en datos críticos de los clientes. En un sistema de comunicaciones por capas, como por ejemplo en el modelo OSI (Open System Interconnection) o TCP/IP (Transmission Control Protocol/Internet Protocol), se pueden llevar a cabo tanto ataques pasivos como activos en los diferentes niveles de la comunicación. Dependiendo de las capas de comunicación utilizadas, distintos mecanismos pueden ser adoptados para lograr la seguridad de la información. Por ejemplo, protocolos estandarizados tales como MACsec [IEE06] o IPsec [KEN05] son empleados normalmente en la capa 2 (capa de enlace de datos) y capa 3 (capa de red), respectivamente. En ambos casos la encriptación es llevada a cabo en cada trama o paquete de datos de forma individual. Para el caso particular de las redes ópticas, el análisis de las amenazas en su capa 1 (capa física) también es considerado crítico para garantizar unas comunicaciones seguras [SKO16], [FUR14]. En este caso se pueden destacar tres tipos de ataques: ataques de inserción de señal, ataques por splitting y ataques a las infraestructuras físicas. Los ataques por splitting son normalmente empleados para espionaje pasivo o para producir degradación en la señal [SKO16], estos se pueden llevar a cabo fácilmente gracias a técnicas de derivación en la fibra. De hecho, hoy en día ya existen métodos de bajo coste para interceptar la señal óptica gracias a dispositivos de acoplamiento óptico y conversores electroópticos sin la necesidad de interferir perceptiblemente en las comunicaciones [ZAF11]. Con el fin de tratar estas amenazas y proteger la confidencialidad de los datos en la capa física, varios mecanismos relacionados con tecnologías fotónicas han sido propuestos [FOK11], por ejemplo OCDM (Optical Code Division Multiplexing) [JI17], SCOC (Secure Communications using Optical Chaos) [HIZ10] o QKD (Quantum Key Distribution) [ELK13]. Otras técnicas, también relacionadas con protocolos de capa física, cifran la información a nivel de bit independientemente de la tecnología fotónica empleada, como la encriptación de los datos del payload en las tramas OTN (Optical Transport Network) [GUA16]. Algunas de las ventajas reivindicadas por estas técnicas de encriptación consisten en cifrar la información “al vuelo” introduciendo un overhead nulo en los datos y una latencia muy baja (en el rango de nanosegundos) en la información transmitida [GUA16]. De hecho, hoy en día ya están disponibles en el mercado equipos de comunicaciones OTN que realizan el cifrado a la velocidad de línea sin mermar el throughput, es decir consiguiendo un rendimiento de la transmisión del 100% [MIC16]. Esto contrasta con lo que hacen ciertos protocolos en otras capas de comunicación [KOL13], [XEN06]. Por ejemplo, IPsec generalmente introduce latencias en el rango de milisegundos. Además, el overhead introducido por IPsec durante el cifrado limita el rendimiento de transmisión a valores entre el 20% y el 90% de la máxima tasa de datos posible sin encriptación [TRO05], [KOL13]. Aparte de lograr la confidencialidad, alguno de los métodos mencionados anteriormente también es capaz de conseguir privacidad contra intrusos pasivos [FOK11], entendiendo esta como la amenaza cuando dichos intrusos pueden detectar simplemente la presencia de comunicaciones, aunque sean incapaces de descifrar el contenido de la información de las mismas. Esta habilidad puede ofrecer seguridad contra ataques basados en el análisis de los patrones del tráfico, que permitirían revelar información del comportamiento de una compañía o instalación. Dentro de los estándares de comunicaciones ópticas, Ethernet es uno de los más empleados hoy día. Un claro ejemplo es el acceso a las redes de transporte ópticas donde este estándar es utilizado normalmente cuando las tasas de acceso superan el gigabit por segundo. Tal y como se muestra en la Fig.1-1, algunas tecnologías de acceso en los tramos de última milla de las CEN (Carrier Ethernet Networks) son Ethernet sobre fibra (Fibra Directa con Ethernet, Ethernet sobre SONET/SDH, Ethernet sobre PON), Ethernet sobre PDH o Ethernet inalámbrico [MET09]. Dos de los estándares ópticos Ethernet más empleados hoy en día son los denominados 1000Base-X y 10GBase-R con tasas de transmisión de 1 Gbps y 10 Gbps, respectivamente.OBJETIVOS-------------------En el caso de las comunicaciones sobre Ethernet óptico no existe ningún mecanismo que logre la mencionada privacidad al mismo tiempo que la confidencialidad, sin que además introduzca un overhead o latencias indeseadas. El objetivo de esta tesis es el de proporcionar soluciones a dos de los estándares ópticos Ethernet más empleados, tales como 1000Base-X o 10GBase-R, logrando las características citadas anteriormente. En general los principales aspectos que se pretenden desarrollar en esta tesis son los siguientes: • Realizar propuestas viables de modificación de ambos estándares, 1000Base-X y 10GBase-R, de forma que se pueda llevar a cabo la encriptación en la capa física. • Lograr la compatibilidad de las nuevas arquitecturas de encriptación con dichos estándares de forma que el hardware electrónico más dependiente del medio de transmisión, como los módulos ópticos SFP, los SERDES o los circuitos de recuperación de reloj y datos, no necesite modificaciones adicionales. • Realizar un estudio de los posibles esquemas de encriptación por streaming que sean capaces de cifrar datos a velocidades superiores a 1 Gbps y adaptarlos a las arquitecturas propuestas. • Estudiar posibles mecanismos para llevar a cabo la sincronización de los módulos de encriptación entre dos terminales remotos.• Lograr que las soluciones propuestas lleven a cabo la encriptación introduciendo la menor latencia posible, al menos en un orden de magnitud igual o inferior al de soluciones en otros estándares de comunicaciones como OTN. • Llevar a cabo un análisis de la seguridad de las soluciones propuestas, incluyendo el estudio de la capacidad de privacidad en las comunicaciones. • Proponer un esquema de chequeo de integridad, autenticación y refresco de claves a nivel de capa física. • Llevar a cabo la implementación y verificación física de las soluciones propuestas.PUBLICACIONES----------------------------[PER19a] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "Chaotic Encryption Applied to Optical Ethernet in Industrial Control Systems". IEEE Transactions on Instrumentation and Measurement, 68(12):4876–4886, Dec 2019. [PER19b] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "Physical Layer Encryption for Industrial Ethernet in Gigabit Optical Links". IEEE Transactions on Industrial Electronics, 66(4):3287–3295, April 2019. [PER19c] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "Chaotic Encryption for 10-Gb Ethernet Optical Links". IEEE Transactions on Circuits and Systems I: Regular Papers, 66(2):859–868, Feb. 2019. [PER19d] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "Self-Synchronized Encryption for Physical Layer in 10Gbps Optical Links". IEEE Transactions on Computers, 68(6):899–911, June 2019. [PER19e] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "Self-Synchronized Encryption Using an FPE Block Cipher for Gigabit Ethernet". In 2019 15th Conference on Ph.D Research in Microelectronics and Electronics (PRIME), pages 81–84, Lausanne, Switzerland, July 2019. [PER20a] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "A New Method for Format Preserving Encryption in High-Data Rate Communications". IEEE Access, 8:21003–21016, 2020. [PER20b] A. Pérez-Resa, M. Garcia-Bosque, C. Sánchez-Azqueta, and S. Celma. "Self-synchronized Encryption for Physical Layer in 1Gbps Ethernet Optical Links". IEEE Access, Pending Acceptance.<br /

Juridical gyroscopic orientation of transnational business negotiations

L'hypothèse de notre doctorat pose qu’il y a une meilleure moyen pour le droit de régler TBN. Pour cet amélioration, un cadre juridique alternatif est nécessaire pour le règlement de négociations commerciales transnationales [TBN] entre des parties privées dans le contexte de vente internationale de marchandises. La prémisse fondamentale réside dans la manière dont les négociations sont généralement mal comprise dans la complexité du pluralisme, contradictoires ou le chevauchement des régimes juridiques entraînant l'incohérence des remèdes de mesures pour les parties commerciales. Même les parties commerciales sophistiquées labeur d’un façon nébuleux de quand et comment les droits et obligations juridiques sont créés. Les parties souvent ne sont pas suffisamment anticiper les obstacles qui peuvent surgir, et comptent souvent sur des accords oraux ou incomplètes qui peut conduire à une interprétation erronée de l'étendue de leurs droits et de leurs obligations les uns envers les autres. La loi a un intérêt dans cette activité innée pour trois raisons : (1) pour protéger les exigences du marché en matière d'efficacité ; (2) en raison de son caractère opportuniste, pour orienter la conduite entre TBN parties; et (3) d'appuyer l'autonomie des parties. Nous mettrons l'accent sur l'expansion de la théorie juridique actuel des négociations dans la recherche d'une nouvelle théorie normative qui pourraient contribuer à l'amélioration du règlement de TBN. Le projet comprendra l'analyse de la théorie de la négociation juridique actuel pour atteindre un portrait de la façon dont le droit juridique vues négociations d'affaires. Nous avons observé la pauvreté des outils juridiques disponibles pour peser des conséquences juridiques de mouvements de négociation. Négociations tangibles peuvent se révéler dans diverses formes d'accords; certains qui sont reconnus par les arbitres si elles passent des tests de validité du contrat alors que d'autres omettent de produire la reconnaissance. Lorsque des accords apparaissent incomplètes, les arbitres sont obligés de refuser l'exécution des accords de négociation ou se tourner vers les rationalisations fictive. À l'inverse, des obligations juridiques au cours des négociations peut être interprétée dans le cadre général du droit des obligations qu'elles ont été prévues entre les parties ou non. Cette étude devrait mettre à jour les menaces de se heurter et normes contradictoires ainsi que des facteurs qui concilie les sources de réglementation juridique vers une culture marchande juridique mondial. L'éclairage d'une nouvelle compréhension des négociations peut être accompli par le biais d'une approche interdisciplinaire des stratégies opérationnelles et de perception, de même que l'examen de l'étique et les séquences comportementales de négociation émique identifiées par les scientifiques du comportement. Les patrons d'affacturage de négociations commerciales séquentiel normative peut fournir des éléments fondamentaux pour exposer l'intangibilité des négociations par la fusion des valeurs normatives émanant de l'autonomie des parties. Les négociations sont souvent considérées comme un phénomène inadapté en droit; voyageant entre les doctrines juridiques traditionnellement séparées. Remontant aux transformations historiques dans la recherche des racines des sources de réglementation peut s'éclairer les négociations à partir de " l'ombre de la loi " dans un modèle révélant l'expansion vers l'interdépendance et de la coopération. La compréhension des facteurs qui influent sur le système normatif que les parties présupposent tout en négociant contribueront ensemble à notre tridimensionnelle analyse de droit comparé. Une nouvelle conscience critique du portrait de négociations seront proposés par l'intermédiaire de l'application de Hogg's co-operative theory of contracts à des négociations, ouvrant la porte à une vision nouvelle de négociations. Configuration par défaut de normes de conduite par le biais d'une théorie de la négociation juridique normative pourrait éventuellement conduire à l'examen de règles sui generis pour surveiller l'évolution de notre société globale afin de la loi de fournir de l'efficacité et l'autonomie nécessaire titrisés par TBN parties. Entre-temps, l'autonomie des parties menant grâce à de nouveaux mécanismes de commerce que nous avons appelé "Bills of Negotiation [BON]", fournissant TBN parties avec des normes claires de communications qui fonctionnent à travers exprimé parti choix pour exprimer les intentions des parties, qui devraient soutenir les normes d'affaires et servir le droit d’inestimables de données empiriques et de preuves.The hypothesis of our doctorate posits that there is a better manner for law to regulate TBN. We posit to improve legal regulation of TBN that an alternative legal framework is necessary for the regulation of transnational business negotiations [TBN] between private parties in context of international sale of goods. The fundamental premise lies in the manner in which negotiations are commonly misunderstood within the complexity of pluralistic, conflicting or overlapping legal regimes causing inconsistent measurement and enforcement of remedies to business parties. Even the most sophisticated business parties toil with the nebulous line of when and how legal rights and obligations are created. Parties do not sufficiently anticipate obstacles that may arise, and often rely on oral or incomplete agreements which may lead to the misinterpretation of the extent of their rights and obligations to one another. The law has an interest in this innate activity for three reasons: (1) to protect market requirements of efficiency; (2) because of its opportunist nature, to guide conduct between TBN parties; and (3) to support party autonomy. We will be focusing on the expansion of current legal theory of negotiations in search of a new normative theory that could contribute to the improvement of regulation of TBN. The project will comprise an analysis of current legal negotiation theory to attain a legal portrait of how law views business negotiations. We have observed the poverty of legal tools available to weigh juridical consequences of negotiation movements. Tangible negotiations may reveal themselves in various forms of agreements; some that are recognized by adjudicators if they pass tests of validity of contract while others fail to produce recognition. When agreements appear incomplete, adjudicators are forced to either deny enforcement of negotiating agreements or turn to fictitious rationalizations. Conversely, legal obligations during negotiations may be construed within the general scope of the law of obligations whether they have been intended between the parties or not. This study is expected to reveal the threats of colliding and conflicting norms as well as factors that reconcile the legal regulatory sources towards a global legal merchant culture. Illuminating a new understanding of negotiations can be accomplished through an interdisciplinary glimpse of business strategies and perception, along with examination of the etic and emic negotiating behavioral sequences identified by behavioral scientists. Factoring patterns of normative sequential business negotiations may provide fundamental elements to expose the intangibility of negotiations by amalgamating normative values emanating from party autonomy. Negotiations are often considered a phenomenon misfit in law; traveling between traditionally separated legal doctrines. Reaching back to historical transformations in search of the roots of the regulatory sources may illuminate negotiations from the “shadow of the law” into a model revealing the expansion into interdependency and cooperation. Comprehension of the factors that influence the normative frameworks that parties presuppose while negotiating together will contribute to our tri-dimensional comparative law analysis. A new critical awareness of the portrait of negotiations will be proposed through the application of Hogg’s co-operative theory of contracts to negotiations, opening the door to a fresh vision of negotiations. Setting default standards of conduct through a normative legal negotiation theory may eventually lead to the consideration of sui generis rules to monitor our evolving global society in order for law to provide the securitized efficiency and autonomy required by TBN parties. Meanwhile, party autonomy may seize leadership through new trade mechanisms which we have termed "Bills of Negotiations [BON]", providing TBN parties with transparent standards of communications that operate through expressed party choice to record parties’ intentions, which are expected to support business norms and serve law with invaluable empirical data and evidence

Effects of Irrigation Rate and Planting Density on Maize Yield and Water Use Efficiency in the Temperate Climate of Serbia

Scarce water resources severely limit maize (Zea mays L.) cultivation in the temperate regions of northern Serbia. A two-year field experiment was conducted to investigate the effects of irrigation and planting density on yield and water use efficiency in temperate climate under sprinkler irrigation. The experiment included five irrigation treatments (full irrigated treatment – FIT; 80% FIT, 60% FIT, 40% FIT, and rainfed) and three planting densities (PD1: 54,900 plants ha–1 ; PD2: 64,900 plants ha–1; PD3: 75,200 plants ha–1). There was increase in yield with the irrigation (1.05–80.00%) as compared to the rainfed crop. Results showed that decreasing irrigation rates resulted in a decrease in yield, crop water use efficiency (WUE), and irrigation water use efficiency (IWUE). Planting density had significant effects on yield, WUE, and IWUE which differed in both years. Increasing planting density gradually increased yield, WUE, and IWUE. For the pooled data, irrigation rate, planting density and their interaction was significant (P < 0.05). The highest two-year average yield, WUE, and IWUE were found for FIT-PD3 (14,612 kg ha–1), rainfed-PD2 (2.764 kg m–3), and 60% FITPD3 (2.356 kg m–3), respectively. The results revealed that irrigation is necessary for maize cultivation because rainfall is insufficient to meet the crop water needs. In addition, if water becomes a limiting factor, 80% FIT-PD3 with average yield loss of 15% would be the best agronomic practices for growing maize with a sprinkler irrigation system in a temperate climate of Serbia

Performance analysis for wireless G (IEEE 802.11G) and wireless N (IEEE 802.11N) in outdoor environment

This paper described an analysis the different capabilities and limitation of both IEEE technologies that has been utilized for data transmission directed to mobile device. In this work, we have compared an IEEE 802.11/g/n outdoor environment to know what technology is better. The comparison consider on coverage area (mobility), throughput and measuring the interferences. The work presented here is to help the researchers to select the best technology depending of their deploying case, and investigate the best variant for outdoor. The tool used is Iperf software which is to measure the data transmission performance of IEEE 802.11n and IEEE 802.11g