Solutions for wireless internet connectivity in remote and rural areas

Abstract. These days internet connectivity is listed in the basic needs of human habitat. Internet provides inevitable support in getting knowledge, professional and social connectivity, entertainment media, and in running majority of businesses. Human dependency on internet for efficient, proficient and time saving work has increased the demand of internet connectivity worldwide. The global index shows a percentage increase in internet users from 16% to 48% (of the world population) from 2005 to 2019. The users are accessing internet via different media, inclusive of fixed lines and wireless connectivity. In wireless connectivity by 2019, 86% of the world population is using mobile broadband services offered by different telecom operators in different regions. Around 44.7% of the world population lives in rural areas as projected in 2018. Telecom operators are now seeking to cover all urban and rural, segregated, and dense, plateaus and hills, small and big geographical areas for internet connectivity. The majority of challenges faced by operators for deployment of internet connectivity services are in rural areas. Internet users cited in rural areas experience poor coverage and bad quality of service (QoS) in wireless internet access. This thesis covers the rural area internet connectivity challenges, existing deployable solutions against the challenges, and provides example solutions to overcome these challenges, to provide wireless network coverage in rural areas of Finland. Many of the existing wireless communication services are directly deployable or adjustable to the remote or rural areas almost the same way as for the urban areas. The major challenge is the low annual revenue per unit and segregated population densities of rural areas, which increase the return of investment time of network service providers. There are other challenges like ease of assembly, technology, backhaul connectivity, and electricity discussed in the thesis. The possible wireless network solutions deployable for wide area network regions and local area network regions are presented in this thesis. Thesis presents all emerging wireless technologies like small cell base station, super tower, balloon Loon project, power line Airgig project, satellite Viasat service, fixed wireless internet, and signal booster. Two possible network solutions for wireless network coverage in rural areas of Finland are analysed in the thesis. Huawei’s RuralStar small cell base station is presented as the first network solution from the viewpoint of network service provider. Hajakaista network services to individual user are presented as the second network solution from the viewpoint of end user. An addition of outdoor router in Hajakaista network architecture is presented as an additional advantage of outdoor Wi-Fi service together with indoor Wi-Fi. The limitations of the network solutions and future work scope are discussed in the discussion part of the thesis.Langattomia tietoliikenneratkaisuja syrjäalueille. Tiivistelmä. Nykyisin internetyhteys nähdään perustarpeeksi koska se antaa pääsyn tietoon, mahdollistaa ammatilliset ja sosiaaliset yhteydet sekä toimii viihdeväylänä ja tärkeänä osana liiketoimintaa. Tämän vuoksi tarve internetyhteydelle on kasvanut maailmanlaajuisesti. Vuonna 2005 maailman ihmisistä 16 % oli yhteys internettiin ja 2019 48 %. Internetyhteys voidaan saada usealla eri tavalla kuten valokuidulla ja langatonta yhteyttä käyttäen. Vuonna 2019 maailman ihmisistä 86 % käytti langatonta tekniikkaa. Vuonna 2018 44,7 % ihmisistä asui maaseutualueilla. Teleoperaattorit yrittävät kattaa kaikki kaupunki- ja maaseutualueet; eristyneet, tasaiset, kukkulaiset, isot ja pienet maantieteelliset alueet. Suurimmat haasteet ovat maaseudulla, jossa ihmiset kokevat huonoa yhteyspeittoa ja yhteyden laatua. Tämä diplomityö tarkastelee, miten nykyisiä langattomia järjestelmiä voitaisiin käyttää maaseudulla toimivien yhteyksien luomiseksi. Työ esittää kaksi esimerkkiratkaisua Suomen olosuhteisiin. Monet nykyisin kaupungeissa käytettävät ratkaisut ovat suoraan tai lähes suoraan sovellettavissa maaseudulle. Päähaasteet ovat matala vuosittainen yksikkötuotto ja hajallaan olevat alueet, jotka syyt kasvattavat investoinnin kuoletusaikaa. Muita haasteita ovat asennus, teknologia, siirtoyhteydet (tukiasemasta verkkoon) ja sähkön saanti, joita tarkastellaan työssä. Mahdollisia langattomia ratkaisuja ovat laajan alueen ja paikalliset ratkaisut, kuten työssä tuodaan esille. Työ tarkastelee solukkoverkkoja, supertornia, palloprojekti Loonia, sähkölinjoihin pohjautuvaa Airgig-projektia, Viasat-satelliittiratkaisua, kiinteää solukkoyhteyttä ja signaalin passiivista vahvistamista. Työ esittää kaksi ratkaisumallia Suomen olosuhteisiin. Toinen perustuu Huawein RuralStar-kevyttukiasemaan, jolla voi jatkaa operaattorin verkkoa. Toinen ratkaisu on kuluttajalähtöinen ja se perustuu Hajakaista Oy:n ratkaisuun. Siinä lisätään Hajakaista Oy:n perusratkaisun eli talon sisäisen Wi-Fi-verkon rinnalle ulkoinen Wi-Fi-verkko. Ratkaisujen rajoitteita tarkastellaan työn keskusteluosuudessa

Physics-Based Approaches For Structural Health Monitoring And Nondestructive Evaluation With Ultrasonic Guided Waves

The engineering infrastructures have a growing demand for damage monitoring systems to avoid any potential risk of failure. Proper damage monitoring solutions are of a great interest to this growing demand. The structural health monitoring (SHM) and nondestructive evaluation (NDE) offer appropriate online and offline damage monitoring solutions for a variety of mechanical and civil infrastructures that includes unmanned aerial vehicles (UAV), spaceships, commercial aircraft, ground transportation, wind turbines, nuclear spent fuel storage tanks, bridges, naval ships, and submarines. The fundamentals of the ultrasonic SHM and NDE consist of multi-disciplinary fields. The dissertation addresses SHM and NDE using ultrasonic guided waves, with an emphasis on the development of an analytical solution for non-axisymmetric guided wave propagation, multiphysics simulation, and experimental study of acoustic emission from the structural fatigue damage. An analytical solution for non-axisymmetric coupled guided wave propagation in plate-like structures was developed based on the equations of motion and elasticity relations. A general non-axisymmetric solution of guided wave propagation inplateis needed to analyze the guided wave-scatter from non-axisymmetric damage as encountered in practice. Under non-axisymmetric conditions, the problem is highly coupled and no potential based analytical solution has been reported in the literature so far. Helmholtz decomposition theorem was applied to the Navier-Lame equations that yielded a set of four coupled partial differential equations in four unknowns, the scalar potential Φ and the three components of the vector potential Hr, Hz, HΘ. A fourth equation, the ‘gauge condition’ was then added to the decomposition. A particular interpretation of the gauge condition is proposed. Our proposed approach decouples the governing equations and reduced the number of unknowns from four to three thus allowing one to express the solution in an elegant straight-forward way. The Rayleigh-Lamb characteristic equations were recovered and a general normal-modes expression for the solution was obtained. A hybrid global analytical and local finite element method was used to solve a practical aerospace rivet hole crack detection. The scatter cube of complex-valued wave damage interaction coefficients (WDICs) was developed to analyze any rivet hole of a multiple-rivet-hole lap joint system. It had been shown that not all parameters such as actuator-sensor locations, and frequencies were equally sensitive to the damage scatter. The optimum combination of parameters could better detect the crack in the rivet hole. The simulated time domain signals were produced for the optimum combination of parameters. Multiphysics simulations for fatigue crack generated acoustic emission (AE) were performed and the results were validated by the experiments. A novel application of inexpensive piezoelectric wafer active sensors (PWAS) has been explored. It has been shown that PWAS transducers successfully captured the fatigue-crack generated acoustic emissions in the thin plate-like aerospace materials. PWAS performance was compared with existing commercial AE sensors. It was found that PWAS captured richer frequency content than the existing AE sensors. Various AE waveform signatures were found from the fatigue crack advancement during the fatigue load evolution. Some AE waveform signatures were found to be related to the fatigue-crack extension while some of them were related to the fatigue-crack fretting, rubbing, and clapping. This observation was confirmed viii by synchronizing the fatigue loading with AE measurement by the same AE instrument. The in-situ microscopic measurement was performed during fatigue loading in MTS which provided the insights of the AE waveform evolution. It was hypothesized that the crack length estimation could be related the AE waveform signatures. FEM simulations and experiments were conducted using laser Doppler vibrometer (LDV) to verify our hypothesis. Two case studies are discussed showing the implementation of SHM and NDE approach in practical applications: (1) horizontal crack detection, size, and shape estimation in stiffened structures, (2) impact damage detection in manufactured aerospace composite structures. The dissertation finishes with conclusions, major contributions, and suggestions for future work

Application of Nonlinear Site Response Analysis in Coastal Plain South Carolina

The 1933 Long Beach, 1957 San Francisco, 1967 Caracas, 1985 Mexico City, 1989 Loma Prieta, and 1994 Northridge earthquake events left evidences of how the local site condition can affect the characteristics of propagating earthquake wave from the bedrock through the top soil. The ground motion amplitude, frequency content or the duration can be affected by the local site condition and thus can cause significant amplification or de-amplification to the original bedrock motion which can seriously affect the structures. Quantification of such site effect on ground motions is a challenging task. This dissertation is dedicated to improve the existing ground response quantification techniques and the related knowledge base. The first major attempt towards ground response quantification was the development of the 1994 NEHRP (BSSC, 1995) seismic site factor provision. Since the development of the NEHRP provisions, several studies have found these factors to produce inadequate predictions for the state of South Carolina. In an attempt to generate seismic site factors based on conditions specific to South Carolina Coastal Plain (SCCP), a series of nonlinear one-dimensional ground response analyses are performed by this author as part of a research team considering appropriate soil profiles and location specific ground excitations. After the generation of this new site factor model, a systematic repercussions study is performed by applying earthquake loads, considering both NEHRP and the new site factors, on typical highway bridge structures

Creating "Good Muslims": Qawmi Madrasa schooling in a rural town of Bangladesh

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis is about the processes and practices that underpin everyday life in a Bangladeshi qawmi madrasa, a rather contentious faith-based Islamic schooling system that is very popular among the rural poor. Based on 15 months of ethnographic fieldwork that took place in Biswanath, a rural town in northeastern Bangladesh, this thesis focuses specifically on the processes that are considered by the qawmi madrasa system to be crucial for the creation of a “good Muslim” persona. The thesis is, therefore, primarily about a particular form of (religious) schooling and (religious) identity formation processes in rural Bangladesh. This study describes a wide range of issues, traditions, and practices embedded within the qawmi madrasa system. The economic and social dynamics of the locality have also been observed closely, as these are directly linked with and influenced by the centrality of Islam in the life of the people. The protagonists of this system believe that every Muslim requires authentic Islamic schooling in order to become a “good Muslim”. Essential to the construction of the “good Muslim” within the qawmi madrasa system therefore lies the assumption that this type of schooling is transformative in nature. Hence, my analysis highlights the centrality of the believer’s body and suggests that for the successful construction of a Muslim persona it is the Islamic orthopraxy, rather than the orthodoxy, that they (learners) receive here most of their faith schoolings on. Central to such orthopraxy is Sunnah (ritual and non-ritual actions approved by the Prophet), which is reinforced and inculcated by the wider community of adults (parents, teachers) into learners by systematically addressing and synchronizing various qualities and expectations through the schooling process. Loyalty is one such quality that both the qawmi protagonists and the wider society believe is infusible. Loyalty towards the moral and social order is thought to be achievable through both moral and corporal discipline. Hence, accustoming one’s body and mind to the knowledge of adab (manner) constitutes the fundamental knowledge of all within this system. In other words, in this study I suggest that the qawmi madrasa system is a system of schooling where adab signifies not only the moral but also the political identity of a person. However, an ideal Muslim persona or an approved Muslim body’s construction within this context also rests on religious beliefs (iman) and deeds (amal). In Bangladesh the qawmi madrasa system is categorized as an ultra orthodox Islamic schooling system on the basis of its stance for authentic and scripture based Islam. However, as I will demonstrate, in reality, the system is sustained by both accommodating many secular expectations of the people and by compromising many of its stances.This work is funded by the Commonwealth Commission and the British Council

Engagement of Information Systems Professionals in Open Source Software Development

Open source (OS) development of software is becoming increasingly desirable for individuals and organizations alike. Organizations that heavily resisted this new way of developing software are now actively participating in this process. Participation of information systems (IS) professionals in the open source environment has been a focal point in this stream of research in information systems. The dissertation goes beyond participation and examines engagement of IS professionals in the open source environment. The concept of engagement facilitates a more comprehensive understanding of the relationship between a person and a his or her work. The three essays in the dissertation examine three aspects of IS professional’s engagement in the open source domain: job engagement, platform engagement, and continued participation. The first essay, using the job characteristics model as a theoretical framework, explores the role of job characteristics in driving job engagement and job satisfaction in open source projects. The second essay examines factors that can influence IS professionals continued contribution to future activities of an open source development platform. Using the social exchange theory, the second essay examines how perceived justice of rewards in OS projects can impact IS professionals’ platform engagement and intention to participate in future platform activities. The third essay explores the role of external feedbacks in open source projects. Using the signaling theory, this essay examines how characteristics of external feedback can interact with motivations to influence continued participation intention. The three essays are expected to enrich the information systems literature by providing new insights on various factors that can enhance engagement of IS professionals in the open source domain. The essays also contribute to the IS literature by applying the job characteristics model, social exchange theory, and signaling theory in the context of open source development

Improving Management and Understanding of Major Diseases of Sugar Beet

Sugar beet is a sugar-yielding crop, that contributes 25% of the global sucrose production. Economic production of sugar beet is hampered by Cercospora leaf spot (CLS) (Cercospora beticola), Rhizoctonia crown and root rot (RCRR) (Rhizoctonia solani), Sclerotinia root rot (SRR) (Sclerotinia sclerotiorum), and Rhizopus root rot (Rhizopus arrhizus) diseases. These diseases can reduce yield by 15 to 40%. On CLS, buildup of fungicide-resistance strains is a major issue due to poor implementation of fungicides and understanding of disease development at early stages. The identification of germplasm resistant to RCRR disease is hindered by the lack of effective inoculation methods. Identification of SRR and RRR pathogens is crucial for their proper management. The objectives of this research were 1. to evaluate the role of adjuvants in improving the efficacy of fungicides on CLS, 2. to characterize the infection process during early stages of infection by C. beticola, 3. to identify an effective inoculation method for RCRR, and 4. to identify and characterize the causal organisms of SSR and RRR. The value of adjuvants was evaluated in greenhouse and field conditions. Application of fungicides with or without adjuvants before disease onset reduced disease severity of CLS in greenhouse condition. In field conditions, additions of adjuvants did not improve the effectiveness of fungicides and few of them negatively impacted root yield. The initial stage of infection on CLS susceptible and resistant sugar beet variety were compared using confocal microscopy. C. beticola biomass accumulation, percent leaf cell death and disease severity were all significantly greater in the susceptible variety compared to the resistant variety (P<0.05). R. solani inoculated on the crown and roots were compared in a replicated trial in greenhouse conditions. The root inoculation method provided a more consistent disease rating of the sugar beet variety in the greenhouse for screening of RCRR cultivars in a resistance breeding program. Based on morphological and molecular techniques, causal organisms of SRR and RRR were characterized and was found to be pathogenic to sugar beet varieties tested in-vitro and in the greenhouse conditions

GENERIC FRAMEWORKS FOR INTERACTIVE PERSONALIZED INTERESTING PATTERN DISCOVERY

The traditional frequent pattern mining algorithms generate an exponentially large number of patterns of which a substantial portion are not much significant for many data analysis endeavours. Due to this, the discovery of a small number of interesting patterns from the exponentially large number of frequent patterns according to a particular user\u27s interest is an important task. Existing works on patter

Impacts of ocean acidification and other (global change) stressors on marine invertebrates

The hypervariable nearshore marine ecosystem is home to intrinsic stressors for marine organisms. Global climate change and human activity are already affecting this aquatic environment and are expected to intensify over the next decades. These diverse changes include a rise in global temperature and a decrease in ocean pH. More carbon dioxide dissolves in the sea, lowers the pH, and makes the ocean more acidic. Now the main scientific challenge is to understand and predict the response of marine life to the predicted environmental change in the ecosystem. These challenges include a better understanding of the marine life’s response to changes in distribution and tribute to evolutionary changes or extinction. Species can respond to global change in a variety of ways. They can move from the environment of tolerance zone to newly available zones, can extend tolerance by summarizing and/or modifying their physiology or behaviour, and can demonstrate that the range shrinks when the environment of certain variable environmental factors is exceeded. Most marine species can respond to transformations, including behavioural or generational genetic selections that can improve perception, individual morphology, physiology, and/or performance in changing environmental conditions when undergoing periodic and rapid changes in the environment. Familiarity and adaptability to a changing environment is a type of environmental reaction due to the plasticity of an organism. In this doctoral dissertation, studies have been carried out to understand the potential physiological or biochemical effects of some global change stressors on five important marine and estuarine invertebrates: the anthuroid isopod Cyathura carinata (Krøyer, 1847), the benthic ragworm Hediste diversicolor (O.F. Müller, 1776), the sea snail Tritia neritea (Linnaeus, 1758), the most versatile amphipod Ampelisca brevicornis (Costa, 1853), and the pseudodiaptomid copepod Calanipeda aquaedulcis (Kritschagin, 1873) from the Iberian Peninsula (SW of Spain), because all of these invertebrates have been abundantly occupying and performing dynamic roles in the estuarine food chain for a long time, they have served as a viable food source for avifauna and ichthyofauna in those areas. In Chapter 3 we investigated the physiological or biochemical plasticity of OA in isopod C. carinata, and in Chapter 4 we describe how OA and ocean warming can alter the physiological and biological changes in a ragworm H. diversicolor. The effects of temperature rises and contamination of emerging pollutants such as lithium on the sea snail are discussed in Chapter 5. To determine whether OA includes propagating effects in the ecotoxicological study, the amphipod A. brevicornis is described in Chapter, 6 and finally, whether intragenerational plasticity can offset the negative effects that OA had on the life cycle of the copepod C. aquaedulcis is described in Chapter 7. To determine the tolerance and pH threshold that C. carinata could tolerate in future acidification scenarios, estuarine isopod was exposed to four pH treatments (control: 7.9; 7.5, 7.0, 6.5). Seawater acidification had a significant impact on the longevity of C. carinata, where the population density decreased significantly when treated at the lowest pH. The longevity, survival, and swimming activity of these isopods decreased with decreasing pH. Also, the swimming activity, Na+/K+-ATPase activity, and the RNA:DNA ratio of two populations of C. carinata, one in a stable environment (pH 7.5-8.0) and the other in a variable pCO2 regime (pH 3.3-8.5), were measured to assess the probable metabolic adaptability of this species. Populations in environments with a high pCO2 regime not only showed tolerance to pH 6.5 but had higher life spans and metabolic plasticity compared to habitat populations with little pCO2 conditions. These results indicate that C. carinata populations in stable environments may be susceptible to ocean acidification and can have a detrimental effect on survival and growth. Nevertheless, ocean acidification has limited effects on the energy budget and survival of C. carinata populations in highly variable habitats, indicating that they can cope with the elevated energy demand. Differences between the indicated populations probably indicate genetic differences in resistance to ocean acidification, possibly related to local adaptation, which may provide the raw materials needed to adapt to future conditions. In addition, our results indicate that population changes and metabolic responses should be considered when evaluating the response of marine crustaceans to changes in the global environment. Ragworm H. diversicolor was exposed in the laboratory to multi-stressors effects of elevated temperature and carbon dioxide levels mimicking the future OA and GC and we assess the physiological, behavioral, and biochemical changes in this species. The temperature rise exacerbated the negative effects of OA on the survival of the ragworm, delayed the excavation, and amplified the negative effects of lowering the pH on the feeding behavior of this polychaete. This is the first time this species has been shown to reduce its feeding capacity through the acidification of seawater. Wound healing and blastemal formation were slowed by these two climatic factors, which interfere with the regeneration process of the ragworm. Current results also show that even if polychaetes' metabolic capacity increases under stress conditions, organisms can still increase or maintain their energy reserves. Our results are of great importance for the environment, given that predictive conditions for climate change will affect the life, ecological and physiological capabilities of the species. This can lead to a decrease not only at the individual and population level but also at the diversity of microbes and endofauna, waste disposal in the estuary, and biochemical cycles at the ecosystem level. Therefore, the conservation of the H. diversicolor population is very important for the normal functioning of the estuary ecosystem. Sea snail Tritia neritea was exposed to lithium (Li, 0.08 mM) contamination and the rising seawater temperature (21 °C). We investigated the survival and trophic interactions (foraging behavior, success, search time, carrion preference, feeding time, and tissue consumption) of this intertidal scavenger. Trophic interactions were assessed using a Ymaze design using the same amount of two carrion species (Solen marginatus and Mytilus galloprovincialis) given simultaneously to all snails. Lithium pollution and synergistic warming reduce the survival rate of T. neritea, triggering a scenario for potential global change. Lithium contamination changes foraging behavior and increases the time it takes for snails to reach their carrion. Although T. neritea did not show a preference for the proposed carrion species in the control group, it shifted its foraging behavior to a more energetic carrion when contaminated with Li, which may represent a strategy that compensates for the high energy use required for survival. Results showing changes in the foraging activity of coastal mollusks in a global change scenario indicate potential changes in complex nutritional interactions between marine food pathways. Estuarine amphipod A. brevicornis was examined to study the physiological behavior and biochemical effects of the amphipod under OA. Wild harvested ovigerous females were reared in the laboratory and we started the experiment with 7 days old juveniles in a simulated OA scenario with four different levels of pH for a life cycle. Amphipods were incubated for up to 22 weeks to go through F1 production, successful reproduction, and hatching, and the length of F1 progeny compared to F0. The data obtained show that as the pH value of seawater decreases, mortality increases. The fertility rate reduced to 66.1% at pH 7.5 compared to the control group. The survival rate was higher in F1 juveniles than in F0 juveniles, but growth showed the opposite tendency to F1. These physiological parameters may be related to oxidative stress caused by climate-changing conditions as free radical generation interferes with cellular function, affecting the biochemical and physiological properties of the species, including burrowing, locomotory and ventilatory behaviours. This study is critical to assessing the impact of OA and providing baseline data that can be used as a guide for developing long-term strategies for delivering manageable and sustainable solutions. Copepods are an integral part of the marine food network due to their high biomass production and nutrient turnover compared to other zooplanktons in the marine ecosystem. Despite its enormous ecological role in the oceans, little is known about the effects of OA from increasing planetary carbon dioxide emissions in the future. Little information is available on the impact of OA on European copepod C. aquaedulcis. The purpose of this study was to investigate the impact of OA across multiple generations (F1 and F2) on survival, maturity, and fertility (hatching success, nauplii formation, and total adult population). C. aquaedulcis were exposed to three different pH gradients to simulate future seawater acidification scenarios. The survival rate of the copepod from nauplius to adult was significantly reduced in pH reduction and across generations. Results have also shown to have a marked effect on fertility, represented by a much smaller number of eggs per female in each generation. Similarly, hatching success showed a downward trend towards lower pH, and F1 females had significantly lower hatching success rates than F0 females. The results presented here appear to be ecologically important as the decline in the fertility of these animals can negatively affect marine feeding pathways. This is because the nutrition and growth of ichthyofauna are highly dependent on this component in the food web