Overlay Cognitive Radio Based on OFDM with Channel Estimation Issues

Cognitive radio (CR) has been proposed as a technology to improve the spectrum efficiency by giving an opportunistic access of the licensed-user spectra to unlicensed users. We consider an overlay CR consisting of a primary macro-cell and cognitive small cells of cooperative secondary base stations (SBS). We suggest studying a CR where an orthogonal frequency division multiplexing is used for both the primary users (PU) and the secondary users (SU). In order to cancel the interferences, a precoding is required at the SBS. Therefore, we first derive the interferences expression due to SU at the PU receiver. Then, zero forcing beamforming (ZFBF) is considered to cancel the interferences. However, applying ZFBF depends on the channels between the SBS and the PU. A channel estimation is hence necessary. For this purpose, we propose to approximate the channel by an autoregressive process (AR) and to consider the channel estimation issue by using a training sequence. The received signals, also called the observations, are considered to be disturbed by an additive white measurement noise. In that case, the AR parameters and the channel can be jointly estimated from the received noisy signal by using a recursive approach. Nevertheless, the corresponding state space representation of the system is non-linear. Then, we propose to carry out a complementary study by compare non-linear Kalman filter based approaches

Credit scoring models for Egyptian banks : neural nets and genetic programming versus conventional techniques

Credit scoring has been regarded as a core appraisal tool of banks during the last few decades, and has been widely investigated in the area of finance, in general, and banking sectors, in particular. In this thesis, the main aims and objectives are: to identify the currently used techniques in the Egyptian banking credit evaluation process; and to build credit scoring models to evaluate personal bank loans. In addition, the subsidiary aims are to evaluate the impact of sample proportion selection on the Predictive capability of both advanced scoring techniques and conventional scoring techniques, for both public banks and a private banking case-study; and to determine the key characteristics that affect the personal loans' quality (default risk). The stages of the research comprised: firstly, an investigative phase, including an early pilot study, structured interviews and a questionnaire; and secondly, an evaluative phase, including an analysis of two different data-sets from the Egyptian private and public banks applying average correct classification rates and estimated misclassification costs as criteria. Both advanced scoring techniques, namely, neural nets (probabilistic neural nets and multi-layer feed-forward nets) and genetic programming, and conventional techniques, namely, a weight of evidence measure, multiple discriminant analysis, probit analysis and logistic regression were used to evaluate credit default risk in Egyptian banks. In addition, an analysis of the data-sets using Kohonen maps was undertaken to provide additional visual insights into cluster groupings. From the investigative stage, it was found that all public and the vast majority of private banks in Egypt are using judgemental approaches in their credit evaluation. From the evaluative stage, clear distinctions between the conventional techniques and the advanced techniques were found for the private banking case-study; and the advanced scoring techniques (such as powerful neural nets and genetic programming) were superior to the conventional techniques for the public sector banks. Concurrent loans from other banks and guarantees by the corporate employer of the loan applicant, which have not been used in other reported studies, are identified as key variables and recommended in the specific environment chosen, namely Egypt. Other variables, such as a feasibility study and the Central Bank of Egypt report also play a contributory role in affecting the loan quality.The Egyptian Governmen

JUVENILE HORMONE BIOSYNTHESIS AND SIGNALING PATHWAY IN DROSOPHILA MELANOGASTER

Insect development and metamorphosis are controlled by two major hormones; 20-hydroxyecdysone (20E) and juvenile hormone (JH). 20E signaling pathway is well recognized while JH signaling is still ambiguous. For a better understanding of JH biosynthesis and signaling we worked on two parallel projects; reverse genetic and forward genetic studies. In the reverse genetic study, we have tested the potential functional redundancy between Methoprene-tolerant (Met) and germ cell-expressed (gce), two paralog bHLH-PAS transcription factors in Drosophila that were suggested to be JH receptors. Met null mutants are viable, resistant to JH and low fecundity. No gce mutant was available at the begening of this project. We generated a gce null allele and found that it phenocopies Met mutants. Met-gce double mutants are lethal at prepupal stage, which is similar to the JH-deficient flies. Krüppel homolog1 (Kr-h1) and broad (br) are two known JH signaling componets. Further investigations revealed that Met-gce double mutant diminishes Kr-h1 expression, induces precocious br expression, and causes premature and enhanced caspase-dependent programmed cell death. Therefore, we conclude that Met and Gce are functionally redundant in transducing JH signals. Expression of br is induced by 20E, but its induction can be suppressed by JH. In the forward genetic study, we designed and conducted a novel genetic screen to isolate mutations that can de-repress br expression at early larval stages. From 4,400 lethal lines, 55 mutations were isolated based on the precocious br expression in 2nd instar larvae. Genes associated with these 55 mutations include apterous, InR, NMAR1, Fpps and Kr-h1, which are known to be involved in JH biosynthesis or signaling. Other genes encode proteins with various molecular functions, including enzymes, signal transduction molecules, and transcriptional factors. Among them, there are three Wnt signaling components, Axin (Axn), supernumerary limbs (slmb), and naked cuticle (nkd) and two TGF-β signaling components, thick vein (tkv) and mothers against Dpp (mad). We further demonstrated that Wnt signaling mediates JH signaling by regulating Met and gce expression, and that TGF-β signaling controls JH biosynthesis by upregulating transcription of JH acid methyltransferase (jhamt), a key regulatory enzyme of JH biosynthesis

Identification Et Cartographie Des Zones Potentielles De Recharge Des Eaux Dans La Région De Dosso (Sud-Ouest, Niger) Par Analyse Multicritère

Les eaux souterraines constituent la principale sourced’approvisionnement en eau des populations de la région de Dosso, située dansle Sud-Ouest du bassin des Iullemmeden. En dépit du climat aride à semi-aridequi caractérise cette région, le renouvellement des eaux des nappessouterraines s’effectue à travers les pluies. Cette recharge des eaux, quiconstitue un élément essentiel dans le cycle hydrologique, se faitpréférentiellement selon des zones qui peuvent aussi être des zonesvulnérables à la pollution des nappes. L’objectif principal de cette étudeconsiste à identifier puis à cartographier les zones potentielles de recharge deseaux. La démarche méthodologique utilisée dans le cadre de ce travail anécessité l’utilisation de l’analyse multicritère combinant le Systèmed’Information Géographique (SIG) et la télédétection. Après le traitement desimages Landsat de Dosso, tous les paramètres influençant les processus derecharge des eaux ont été intégrés au SIG. Il s’agit : des types de sol, del’occupation du sol, des densités des fractures et du drainage, de la lithologiede la zone non saturée et de la pente du terrain. La carte des zones potentiellesde recharge des eaux montre que la majorité de la zone étudiée présente unpotentiel réel d’infiltration des eaux lié à : la nature sableuse des sols, laprésence des zones de cultures pluviales, la présence de fractures et la densitédu réseau hydrographique. Cette carte a aussi permis de confirmer que leszones à potentiel élevé de recharge se situent dans les lits des mares et des"dallols" (larges vallées sèches), qui deviennent ainsi des zones plusvulnérables. Ce support cartographique constitue de ce fait un outil d’aide à ladécision. Groundwater is the main source of water supply in the Dosso regionwhich is located in the southwestern part of the Iullemmeden Basin. Despitethe arid to semi-arid climate that characterizes this region, groundwaterrecharge is occuring mainly through rainfall. This recharge of water which isan essential element in the hydrological cycle is prefentially done accordingto zones which can also be vulnerable to groundwater pollution. The mainobjective of this study is to identify and mapped the potential recharge areas.A methodology based on a multicriteria analysis integrating GIS and remotesensing was used to map the potential recharge areas. After processing theLandsat satellite images of Dosso region, all the parameters influencing thehydrological recharge processes were obtained and integrated into GIS. Theseparameters are: soil types, land cover, fracture density, drainage density,lithology and slope. The map of potential recharge areas obtained shows thatthe majority of the study areas has great recharge potential. According to thisstudy, this great potentiality could be linked to: the sandy nature of the soil,the cultivable areas, the presence of fractures and density of hydrographicnetwork. This map also confirmed that areas with high recharge potential arelocated in the beds of ponds and "dallols" (wide dry valleys), which thusbecome more vulnerable areas. This map of potential recharge areasconstitutes therefore a tool for decision makers

SELECTION OF BEST SITES FOR AQUIFER STORAGE AND RECOVERY IN THE EASTERN DISTRICT OF ABU DHABI EMIRATE, UNITED ARAB EMIRATES

The Emirate of Abu Dhabi relied on groundwater as the main source of fresh water for several decades in the past. This resulted in the deterioration of the non-renewable groundwater aquifers; and thus, desalination plants have become the major source of freshwater supply in the United Arab Emirates (UAE). Diminishing natural groundwater is a serious threat to freshwater security in arid regions. Because UAE has the world’s highest per capita water consumption rate, more than 70 desalination plants have been built in the last two decades. A major concern, therefore, is the vulnerability of these desalination plants to pollution and emergency conditions. In emergency conditions, the maximum amount of stored water in reservoirs and distribution systems will be enough for only 48 hours. Currently, the production of these plants exceeds national water demand and the surplus is used to recharge groundwater in specific locations. While production of desalination plants is constant, demand is continuously increasing and soon will exceed production, and then new plants will be needed. This would require investments of billions of Dirhams; not to mention the effect of these plants on the environment. In other words, the construction of new desalination plants cannot continue forever. The main aim of this thesis will be on increasing strategic water reserves in the Eastern District of Abu Dhabi by selecting the best locations for Aquifer Storage & Recovery (ASR). A limiting factor in applying ASR technology is the lack of suitable sites. Finding the best locations for artificial recharge is one of the crucial design steps. ASR technology offers an opportunity to store large volumes of water for later beneficial use. The artificial aquifer recharge with water for a variety of applications has been successfully used worldwide. There is a range of methods used to recharge aquifers, including infiltration systems and injection wells. The choice of method depends on the type of aquifer, land area available, and intended uses of the recovered water. Upon completion, this study would enhance water management in the Al-Ain region to build a backup reservoir to face potential threats of shortage in freshwater supply from desalination plants. Many hydrogeological factors need to be considered during the site selection process for ASR projects. These factors will be considered to assess the hydrological feasibility includes identifications of the best geological layers to receive the injected water. This work will provide a feasibility study of implementing managed aquifer recharge projects in the Al-Ain region, to increase the groundwater storage in suitable sites in the Al-Ain region and modeling the groundwater aquifers and the feasibility to extract water from an aquifer to satisfy critical needs if a reserve had been established through the implementation of an ASR program

Desert Related Traditional Knowledge, Policies and Management in Wadi Allaqi, South Eastern Desert, Egypt

Traditional knowledge in the desert. By Hanaa Ali Hassaan How do Bedouins survive, living in the dry desert? Part of the secret can be found in their Traditional Knowledge (TK), about plants, rangeland, pastoralism and settlement related issues. Such TK, that supports social resilience to endure harsh conditions, is vanishing because of political and socio-economic conditions. Also globally, traditional knowledge is at stake, notwithstanding intentions laid down in international policy conventions. This thesis describes the TK that has played a role in the subsistence of Bedouins living in the extreme conditions of Wadi Allaqi Biosphere Reserve, Southeastern Desert of Egypt. In this study, we investigated the impact of the formation of Lake Nasser in the mid-1960s and the establishment of a new village in the vicinity of the lake in the early 2000s on TK of a Bedouin community. First, we studied whether Bedouin knowledge of plant species has changed in the context of socio-economic changes during the last 50 years. Then, we focused on items relating to rangelands and settlements. Next, we analyzed whether TK plays a role in Egyptian policy, as reflected in policy documents and in interviews with regional stakeholders. Finally, we explored a possible role of citizen science approaches in the conservation and application of TK in Southern Egypt. Based on interviews with and observations of Bedouin people we demonstrated that indigenous, botanical knowledge gets lost, and that several cultural aspects of Bedouin culture are vanishing. At the other hand new agricultural knowledge has been developed with regard to the use of aquatic species, especially as a source of fodder for their herds of goats. Notwithstanding international conventions on traditional knowledge, practical interest is very limited within regional Egyptian policy, research and education. Derived recommendations imply that a stronger position of TK in regulation and law should be supplemented by social measures and actions, taking into account the perspective of the Bedouin community, in a citizen science approach of public participation. This research, supported by Nuffic, has been carried out under the supervision of Dr. Sjaak Swart and Prof. Dr. Menno Gerkema at the Energy and Sustainability Research Institute of the University of Groningen

Reactions with hydrazonoyl halides 66: Synthesis of some new 1,3,4-thiadiazoles, triazolino[4,3-a]pyrimidines and isoxazolo[3,4-d]pyridazines containing coumarin moiety

2,3-Dihydro-1,3,4-thiadiazoles, triazolino[4,3-a]pyrimidines, isoxazoles and isoxazolo[3,4-d]pyridazines containing coumarin moities were synthesized from the reactions of methyl (or benzyl) carbodithioate, pyrimidine-2-thione and 3-(3-(dimethylamino)acryloyl)-2H-chromen-2-one derivatives with C-coumarinoyl-N-phenylhydrazonoyl bromide. The structures of all the newly synthesized compounds were confirmed by elemental analyses and spectral data

On manimax theory in two Hilbert spaces

In this paper, we investigated the minimax of the bifunction J:H1(Ω)xV2→RmxRn, such that J(v1,v2)=((12a(v1,v1)−L(v1)),v2) where a(.,.) is a finite symmetric bilinear bicontinuous, coercive form on H1(Ω) and L belongs to the dual of H1(Ω)

Impacts des banquettes dans la récupération des terres dégradées au Niger

Objectifs : Le département de Ouallam au Niger est soumis au phénomène de dégradation des terres. La présente étude, conduite sur le plateau dégradé de Sini Bangou dans la Commune de Simiri, a pourobjectif d’évaluer l’efficacité du dispositif des banquettes anti-érosives sur l’amélioration de la couverture végétale et de la qualité du sol.Méthodologie et résultats : Le dispositif expérimental de collecte des données est un site de récupération des terres où des banquettes ont été réalisées, plantées et ensemencées. La méthodologie a consisté à une analyse diachronique de l’occupation du sol à l’aide des images Landsat, une analyse granulométrique, des tests d’infiltration de l’eau et des relevés phytosociologiques. Les résultats montrentune amélioration du couvert végétal de 17,24 ha, soit 11,50% de la superficie du site, l’apparition d’une végétation spontanée de 69 espèces dont 11 ligneuses appartenant à 7 familles et 58 herbacées réparties dans 15 familles dominées par la famille des Poaceae (31,88%) et les types biologiques Thérophytes (69,01%).Les espèces à distribution Soudano-Zambéziennes (33,21%)etSoudano-Zambéziennes-Sahariennes-Sindiennes(31,15%) sont les types phytogéographiques les plus dominants de la flore globale à l’échelle africaine. La vitesse de l’infiltration relativement lente enregistrée pendant les dix premières minutes (≤ 10 cm/mn), a progressé au rythme d’une moyenne de 1 cm/mn en profondeur pour s’arrêter aubout de 30 minutes au profit d’une infiltration latérale. L’épaisseur des dépôts de sédiments varie entre 9 et 15 cm selon les banquettes et la teneur en matière organique fluctuant entre 0,36 à 1,43%, quoique faible, reste plus importante au niveau des horizons de surface de 0-20 cm que ceux de profondeur 20-40 cm. Ces effets associés au caractère dominant sableux du sol ont permis l’amélioration de l’état structural et textural de ce dernier et l’augmentation de l’infiltration et du stockage de l’eau qui aurait résulté au développement quantitatif et qualitatif du couvert végétal.Conclusion et application des résultats : Cette étude montre que les banquettes constituent une méthode efficace pour régénérer le capital productif d’un écosystème dégradé. Cependant, la pérennité des services écosystémiques de l’aménagement devrait être garantie par des modes de gestion rationnelle. Objectives: The department of Ouallam in Niger is subject to land degradation. The study was conducted on the degraded area of Sini Bangou in the district of Simiri with the aim to assess the effectiveness of the anti-erosion terraces system on improving plant cover and soil quality.Methodology and results: Experimental data collection design was a degraded land site where terraces have been made with tree plantation and herbaceous seeds sown. The methodology consisted of a diachronic analysis of land use using Landsat images, a granulometric analysis, water infiltration tests and phytosociological surveys. Results show an improvement in the plant cover of 17.24 ha, or 11.50% of the site area, a spontaneous vegetation of 69 species made up of 11 woody ones belonging to 7 families and 58 herbaceous ones distributed into 15 families dominated by the family of Poaceae (31.88%) and the biological types of Therophytes (69.01%). Soudano-Zambezian (33.21%) and Soudano-Zambezian-Saharan-Sindian (31.15%) species are the most dominant phytogeographic types of the overall flora on anafrican scale. The relatively slow infiltration speed recorded during the first ten minutes (≤ 10 cm / min), increased at the rate of an average of 1 cm / min in depth to stop after 30 minutes in favour of a lateral infiltration. Sediment deposits thickness varied between 9 and 15 cm depending on the terraces and the organic matter content fluctuating between 0.36 to 1.43%, although low, remains greater at the level of the surface horizons of 0-20 cm than those of 20-40 cm deep. These effects associated with the dominant sandy character of the soil allowed the structural and textural soil state improvement and the increase inthe water infiltration and storage which would have resulted in the quantitative and qualitative development of the plant cover.Conclusion and application of findings: The study shows that terraces are an effective method forregenerating the productive capital of a degraded ecosystem. However, the sustainability of the ecosystem services of the treated area should be guaranteed by rational management methods

Effect of Perceived Nursing Work Environment on Nurses Job Outcomes at Primary Health Care Centers – Jeddah

During the new and modern era, the organizations are facing many challenge and diversity of workforces in the health care system because the nursing environment has energetic characteristics for nurses.  In addition, nurses are exposed to an unfavorable environment that affects their practice. Therefore, the healthy nursing work environment is essential for increasing satisfaction of their professional nurses needs through attracting, retaining, and rendering quality of patient care in the hospitals. This study aims to investigate the perception of the nursing work environment on nurses' job outcomes at primary health care centers- Jeddah. A descriptive correlational namely cross-sectional design was employed to collect data using non-probability convenience sampling technique from a group of nurses who accept to participate in the study and working at three primary health care centers affiliated to the Ministry of National Guard in Jeddah region namely; Al-Bahra, Alwaha, and Al-Eskan. The questionnaires were administered to the nurses for data collection using socio-demographic characteristics, Revised Nurse Working Index (NWI-R), Nurses' job outcome was measured through of (a) job satisfaction, (b) intention to leave, and (c) quality of nursing care. Statistical analysis was done using SPSS 20.0.  Also, data was analyzed by using descriptive statistics such as mean and standard deviation and inferential statistics such t-tests (two-tailed) and one way analysis of variance (ANOVA) and Pearson correlations were conducted to investigate the relationships of nursing work  environments and the nurses job outcome. In this study the level of significant was set at 0.05.The present study finds that majority of the nurses had a highest percentage of nursing work environment dimensions. For achieving a high level of nursing work environment it is found that there is statistically significant relationship with nurses' job outcomes in term of job satisfaction. Most of the nurses were satisfied with the work and have the highest means scores in term of growth satisfaction, followed by Co-workers and supervision. Job security was reported to have lowest means scores by nurses. There was a significant relationship between socio-demographic variables with the nursing work environment and nurses' job outcomes in term of primary health care centers, educational qualification, and age group. This study recommended that Hospital administrators should advocate and support the policies and regulations that foster nurses' satisfaction by providing a strong nursing work environment and recognizing more productivity for delivering nursing care in primary health care settings Keyword: nursing work environment, job satisfaction, intention to leave, primary health care DOI: 10.7176/JHMN/63-07 Publication date:June 30th 201