Search results for: autonomous outdoor flight

Authors: Emeka Thaddues Njoku

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Since 2009, the Nigerian Government has established diverse counter-terrorism legislations and practices in response terrorism in North Eastern part of the country. However, these measures have hampered not only the ability of civil society organizations to sustain the autonomous spaces that define/locate them at the intersection between the state and public but also the balance between freedom and security. Hence, this study examines the various elements associated with the interface between the counter terrorism security framework of the government and the capacity of civil society organizations to carry out their mandates in Nigeria. In order to achieve this, the survey research of the ex-post facto type will be adopted using the multi-stage sampling technique. A total of two hundred (200) copies of questionnaire will be administered to members of the civil society organizations and 24 In-Depth Interviews (IDI) will be conducted for officials of security agencies, Ministry of Defence and operators of civil society organizations. Fifty respondents will be drawn from each civil society organisations in the areas of humanitarian assistance, human rights Advocacy, development-oriented, peace-building. Moreover, 24 interviewees drawn from the key members of the security agencies (6), Ministry of Defence (6) and 12 operators of civil society organizations-three respondents each will represent the four civil society organizations mentioned above. Also, secondary data will be used to complement In-depth Interview (IDI) sessions. All collected data will be coded and analysed using descriptive statistics of frequency counts and simple percentage in the Statistical Package for Social Science (SPSS). Content analysis will be used for the In-depth interview and secondary data.

Keywords: counter-terrorism, civil society organizations, freedom, terrorism

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Authors: Ridho Widyantama Putra, Endang Wiwik Dyah Hastuti

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The study area is located in Lahat Regency, South Sumatra and is part of a 500 m – 2000 m elevated perbukitan barisan zone controlled by the main fault of Sumatra (Semangko Fault), administratively located on S4.08197 - E103.01403 and S4.16786 - E103.07700, the product of Semangko Fault in the form of normal fault flight trending north-southeast, composed of lithologic is a pyroclastic rock, volcanic rock and plutonic rock intrusion. On the Manna and Enggano sheets of volcanic quartenary products are located along perbukitan barisan zone. Petrology types of pyroclastic rocks encountered in the form of welded tuff, tuff lapilli, agglomerate, pyroclastic sandstone, pyroclastic claystone, and lava. Some pyroclastic material containing sulfide minerals (pyrite), the type of sedimentation flow with different grain size from ash to lapilli. The present of tuff lapilli covers almost 50% of the total research area, through observation petrography encountered minerals in the form of glass, quartz, palgioklas, and biotite. Lava in this area has been altered characterized by the presence of minerals such as chlorite and secondary biotite, this change is caused by the structure that develops in the hilly zone and is proved by the presence of secondary structures in the form of stocky and normal faults as well as the primary structure of columnar joint, From medial facies to distal facies, the division of facies is divided based on geomorphological observations and dominant types of lithology.

Keywords: tuff lapili, pyroclastic, mineral, petrography, volcanic, lava

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Authors: Syed Muhammad Basit Ali, Usama Saleem, Irtiza Ali

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Internal combustion engines have been pioneers in the aviation industry, use of piston engines for aircraft propulsion, from propeller-driven bi-planes to turbo-prop, commercial, and cargo airliners. To provide an adequate amount of thrust piston engine rotates the propeller at a specific rpm, allowing enough mass airflow. Thrust is the only forward-acting force of an aircraft that helps heavier than air bodies to fly, depending on the mathematical model and variables included in that with the correct measurement. Test-benches have been a bench-mark in the aerospace industry to analyse the results before a flight, having paramount significance in reliability and safety engineering, depending on the mathematical model and variables included in that with the correct measurement. Calculation of thrust from a piston engine also depends on environmental changes, the diameter of the propeller, and the density of air. The project would be centered on piston engines used in the aviation industry for light aircraft and UAVs. A static thrust test bench involves various units, each performing a designed purpose to monitor and display. Static thrust tests are performed on the ground, and safety concerns hold paramount importance. The execution of this study involves research, design, manufacturing, and results based on reverse engineering initiating from virtual design, analytical analysis, and simulations. The final evaluation of results gathered from various methods such as co-relation between conventional mass-spring and digital loadcell. On average, we received 17.5kg of thrust (25+ engine run-ups – around 40 hours of engine run), only 10% deviation from analytically calculated thrust –providing 90% accuracy.

Keywords: aviation, aeronautics, static thrust, test bench, aircraft maintenance

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Authors: Melissa Hachem, Maxime Loizeau, Nadine Saleh, Isabelle Momas, Lynda Bensefa-Colas

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Professional drivers are exposed inside their vehicles to high levels of air pollutants due to the considerable time they spend close to motor vehicle emissions. Little is known about ultrafine particles (UFP) or black carbon (BC) adverse respiratory health effects compared to the regulated pollutants. We aimed to study the short-term associations between UFP and BC concentrations inside vehicles and (1) the onset of mucosal irritation and (2) the acute changes in lung function of Parisian taxi drivers during a working day. An epidemiological study was carried out on 50 taxi drivers in Paris. UFP and BC were measured inside their vehicles with DiSCmini® and microAeth®, respectively. On the same day, the frequency and the severity of nose, eye, and throat irritations were self-reported by each participant and a spirometry test was performed before and after the work shift. Multivariate analysis was used to evaluate the associations between in-taxis UFP and BC concentrations and mucosal irritation and lung function, after adjustment for potential confounders. In-taxis UFP concentrations ranged from 17.9 to 37.9 × 103 particles/cm³ and BC concentrations from 2.2 to 3.9 μg/m³, during a mean of 9 ± 2 working hours. Significant dose-response relationships were observed between in-taxis UFP concentrations and both nasal irritation and lung function. The increase of in-taxis UFP (for an interquartile range of 20 × 103 particles/cm3) was associated to an increase in nasal irritation (adjusted OR = 6.27 [95% CI: 1.02 to 38.62]) and to a reduction in forced expiratory flow at 25–75% by −7.44% [95% CI: −12.63 to −2.24], forced expiratory volume in one second by −4.46% [95% CI: −6.99 to −1.93] and forced vital capacity by −3.31% [95% CI: −5.82 to −0.80]. Such associations were not found with BC. Incident throat and eye irritations were not related to in-vehicle particles exposure; however, they were associated with outdoor air quality (estimated by the Atmo index) and in-vehicle humidity, respectively. This study is the first to show a significant association, within a short-period of time, between in-vehicle UFP exposure and acute respiratory effects in professional drivers.

Keywords: black carbon, lung function, mucosal irritation, taxi drivers, ultrafine particles

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Authors: Boudraa Wahiba, Chettibi Farah, Lahlah Naouel, Bouslama Zihad, Houhamdi Moussa

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The marsh of Boussedra (55 ha) is a peri-urban wetland, located in the city of El - Bouni, wilaya of Annaba (North-east of the Algeria). This city hosts every year, 53 species of waterfowl, belonging to 15 different families, of which the most represented family is the Anatidae with almost 12 species. The Glossy ibis (Plegadis falcinellus) is the only representative of the family of the threskiornithidae. After a total absence for almost a decade, this species has established in North Africa and started breeding since 2000. The Glossy ibis (plegadis falcinellus), breeds with low numbers in distant areas. At the wetland of Boussedra, the population of this species was observed with numbers approaching 160 individuals. During the breeding season of 2014 (between march and july), this species bred in mixed heronries (Cattle egret Bubulcus ibis , Little egret Egretta garzetta, The black-crowned night heron Nycticorax nycticorax , Squacco heron Ardeola ralloides and Little bittern Ixobrychus minutus), where a total of 120 nests were counted. This represents the largest colony observed in North Africa. The reproduction of the studied species took place on a Tamaricaceae (Tamarix gallica), where more than 2000 nest were constructed. During this breeding season, we have monitored the colony's installation and evolution and tried to characterize the reproduction, at the urban water plan of Boussedra (measurements of nests, measurements of eggs and monitoring the growing rate and weight gaining of the chicks, since their birth until their flight).

Keywords: glossy ibis, reproduction, peri-urban wetland, mixed heronry, Boussedra, Algeria

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Authors: Matthew D. Baffa

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Infrared thermography is a non-destructive test method used to estimate surface temperatures based on the amount of electromagnetic energy radiated by building envelope components. These surface temperatures are indicators of various qualitative building envelope deficiencies such as locations and extent of heat loss, thermal bridging, damaged or missing thermal insulation, air leakage, and moisture presence in roof, floor, and wall assemblies. Although infrared thermography is commonly used for qualitative deficiency detection in buildings, this study assesses its use as a quantitative method to estimate the overall thermal conductance value (U-value) of the exterior above-grade walls of a study home. The overall U-value of exterior above-grade walls in a home provides useful insight into the energy consumption and thermal comfort of a home. Three methodologies from the literature were employed to estimate the overall U-value by equating conductive heat loss through the exterior above-grade walls to the sum of convective and radiant heat losses of the walls. Outdoor infrared thermography field measurements of the exterior above-grade wall surface and reflective temperatures and emissivity values for various components of the exterior above-grade wall assemblies were carried out during winter months at the study home using a basic thermal imager device. The overall U-values estimated from each methodology from the literature using the recorded field measurements were compared to the nominal exterior above-grade wall overall U-value calculated from materials and dimensions detailed in architectural drawings of the study home. The nominal overall U-value was validated through calendarization and weather normalization of utility bills for the study home as well as various estimated heat loss quantities from a HOT2000 computer model of the study home and other methods. Under ideal environmental conditions, the estimated overall U-values deviated from the nominal overall U-value between ±2% to ±33%. This study suggests infrared thermography can estimate the overall U-value of exterior above-grade walls in low-rise residential homes with a fair amount of accuracy.

Keywords: emissivity, heat loss, infrared thermography, thermal conductance

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Authors: Tuğçe Kiper Elibol, İbrahim Uslan, Mehmet Ali Guler, Murat Buyuk, Uğur Yolum

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According to the FAA report, 142603 bird strikes were reported for a period of 24 years, between 1990 – 2013. Bird strike with aerospace structures not only threaten the flight security but also cause financial loss and puts life in danger. The statistics show that most of the bird strikes are happening with the nose and the leading edge of the wings. Also, a substantial amount of bird strikes is absorbed by the jet engines and causes damage on blades and engine body. Crash proof designs are required to overcome the possibility of catastrophic failure of the airplane. Using computational methods for bird strike analysis during the product development phase has considerable importance in terms of cost saving. Clearly, using simulation techniques to reduce the number of reference tests can dramatically affect the total cost of an aircraft, where for bird strike often full-scale tests are considered. Therefore, development of validated numerical models is required that can replace preliminary tests and accelerate the design cycle. In this study, to verify the simulation parameters for a bird strike analysis, several different numerical options are studied for an impact case against a primitive structure. Then, a representative bird mode is generated with the verified parameters and collided against the leading edge of a training aircraft wing, where each structural member of the wing was explicitly modeled. A nonlinear explicit dynamics finite element code, LS-DYNA was used for the bird impact simulations. SPH methodology was used to model the behavior of the bird. Dynamic behavior of the wing superstructure was observed and will be used for further design optimization purposes.

Keywords: bird impact, bird strike, finite element modeling, smoothed particle hydrodynamics

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Authors: Mostafa Mjahed

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This paper concerns the control of a nonlinear system using two different methods, reference model and genetic algorithm. The quadcopter is a nonlinear unstable system, which is a part of aerial robots. It is constituted by four rotors placed at the end of a cross. The center of this cross is occupied by the control circuit. Its motions are governed by six degrees of freedom: three rotations around 3 axes (roll, pitch and yaw) and the three spatial translations. The control of such system is complex, because of nonlinearity of its dynamic representation and the number of parameters, which it involves. Numerous studies have been developed to model and stabilize such systems. The classical PID and LQ correction methods are widely used. If the latter represent the advantage to be simple because they are linear, they reveal the drawback to require the presence of a linear model to synthesize. It also implies the complexity of the established laws of command because the latter must be widened on all the domain of flight of these quadcopter. Note that, if the classical design methods are widely used to control aeronautical systems, the Artificial Intelligence methods as genetic algorithms technique receives little attention. In this paper, we suggest comparing two PID design methods. Firstly, the parameters of the PID are calculated according to the reference model. In a second phase, these parameters are established using genetic algorithms. By reference model, we mean that the corrected system behaves according to a reference system, imposed by some specifications: settling time, zero overshoot etc. Inspired from the natural evolution of Darwin's theory advocating the survival of the best, John Holland developed this evolutionary algorithm. Genetic algorithm (GA) possesses three basic operators: selection, crossover and mutation. We start iterations with an initial population. Each member of this population is evaluated through a fitness function. Our purpose is to correct the behavior of the quadcopter around three axes (roll, pitch and yaw) with 3 PD controllers. For the altitude, we adopt a PID controller.

Keywords: quadcopter, genetic algorithm, PID, fitness, model, control, nonlinear system

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Authors: S. Malebary, W. Xu

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Antennas are important components that enable transmitting and receiving signals in mid-air (wireless). The radiation pattern of omni-directional (i.e., dipole) antennas, reflects the variation of power radiated by an antenna as a function of direction when transmitting. As the performance of the antenna is the same in transmitting and receiving, it also reflects the sensitivity of the antenna in different directions when receiving. The main observation when dealing with omni-directional antennas, regardless the application, is they equally radiate power in all directions in reference to Equivalent Isotropically Radiated Power (EIRP). Disseminating radio frequency signals in an omni-directional manner form a doughnut-shape-field with a cone in the middle of the elevation plane (when mounted vertically). In this paper, we investigate the existence of this physical phenomena namely silence cone zone (the zone where radiated power is nulled). First, we overview antenna types and properties that have the major impact on the shape of the electromagnetic field. Then we model various off the shelf dipoles in Matlab based on antennas’ features (dimensions, gain, operating frequency, … etc.) and compare the resulting radiation patterns. After that, we validate the existence of the null zone in Omni-directional antennas by conducting experiments and generating waveforms (using USRP1 and USRP2) at various frequencies using different types of antennas and gains in indoor/outdoor. We capture the generated waveforms around antennas' null zone in the reactive, near, and far field with a spectrum analyzer mounted on a drone, using various off the shelf antennas. We analyze the captured signals in RF-Explorer and plot the impact on received power and signal amplitude inside and around the null zone. Finally, it is concluded from evaluation and measurements the existence of null zones in Omni-directional antennas which we plan on extending this work in the near future to investigate the usability of the null zone for various applications such as localization and path finding.

Keywords: antennas, amplitude, field regions, frequency, FSPL, omni-directional, radiation pattern, RSSI, silence zone cone

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Authors: Herath M. P. C. Jayaweera, Samer Hanoun

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Path planning for on-time obstacle avoidance is an essential and challenging task that enables drones to achieve safe operation in any application domain. The level of challenge increases significantly on the obstacle avoidance technique when the drone is following a ground mobile entity (GME). This is mainly due to the change in direction and magnitude of the GME′s velocity in dynamic and unstructured environments. Force field techniques are the most widely used obstacle avoidance methods due to their simplicity, ease of use, and potential to be adopted for three-dimensional dynamic environments. However, the existing force field obstacle avoidance techniques suffer many drawbacks, including their tendency to generate longer routes when the obstacles are sideways of the drone′s route, poor ability to find the shortest flyable path, propensity to fall into local minima, producing a non-smooth path, and high failure rate in the presence of symmetrical obstacles. To overcome these shortcomings, this paper proposes an on-time three-dimensional obstacle avoidance method for drones to effectively and efficiently avoid dynamic and static obstacles in unknown environments while pursuing a GME. This on-time obstacle avoidance technique generates velocity waypoints for its obstacle-free and efficient path based on the shape of the encountered obstacles. This method can be utilized on most types of drones that have basic distance measurement sensors and autopilot-supported flight controllers. The proposed obstacle avoidance technique is validated and evaluated against existing force field methods for different simulation scenarios in Gazebo and ROS-supported PX4-SITL. The simulation results show that the proposed obstacle avoidance technique outperforms the existing force field techniques and is better suited for real-world applications.

Keywords: drones, force field methods, obstacle avoidance, path planning

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Authors: Jan Bohata, Stanislav Zvanovec, Matej Komanec, Jakub Jaros, David Hruby

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Even though there is a rapid development in new optical networks, still optical communication infrastructures remain composed of thousands of kilometers of aging optical cables. Many of them are located in a harsh environment which contributes to an increased attenuation or induced birefringence of the fibers leading to the increase of polarization mode dispersion (PMD). In this paper, we report experimental results from environmental optical cable tests and characterization in the climate chamber. We focused on the evaluation of optical network reliability in a harsh environment. For this purpose, a special thermal chamber was adopted, targeting to the large temperature changes between -60 °C and 160 C° with defined humidity. Single mode optical cable 230 meters long, having six tubes and a total number of 72 single mode optical fibers was spliced together forming one fiber link, which was afterward tested in the climate chamber. The main emphasis was put to the polarization mode dispersion (PMD) changes, which were evaluated by three different PMD measuring methods (general interferometry technique, scrambled state-of-polarization analysis and polarization optical time domain reflectometer) in order to fully validate obtained results. Moreover, attenuation and chromatic dispersion (CD), as well as the PMD, were monitored using 17 km long single mode optical cable. Results imply a strong PMD dependence on thermal changes, imposing the exceeding 200 % of its value during the exposure to extreme temperatures and experienced more than 20 dB insertion losses in the optical system. The derived statistic is provided in the paper together with an evaluation of such as optical system reliability, which could be a crucial tool for the optical network designers. The environmental tests are further taken in context to our previously published results from long-term monitoring of fundamental parameters within an optical cable placed in a harsh environment in a special outdoor testbed. Finally, we provide a correlation between short-term and long-term monitoring campaigns and statistics, which are necessary for optical network safety and reliability.

Keywords: optical fiber, polarization mode dispersion, harsh environment, aging

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Authors: Rubaiyat Jahan

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This paper reports some findings of a study on the issues related to teacher autonomy in the Bangladeshi school contexts, and data of this research was collected from fourteen practicing English teachers of Bangladesh through semi structured interviews. The theoretical underpinning of teacher autonomy, on an apparent note, focuses on the behavioral aspects of teacher autonomy hence emphasizing mostly on the teachers’ capacity for self-directed acts of teaching and self-directed acts of professional development. Yet, a contemporary literature survey of teacher autonomy seems to be concerned more on the political interpretations of teacher autonomy. Thus, autonomous teachers are expected to generate their personal theories of teaching from their practices. The idea of personal theories of practice upholds the view that along with the teaching, teachers need to engage themselves in various classroom based research with a view to theorising from their practices. The findings of this research indicate enormous evidence of behavioral aspects of teacher autonomy. As the data of this research suggests, the participant teachers’ understanding of classroom situations, their reflections on the situational realities and opting for classroom decisions on the basis of those realizations are some good examples of teacher autonomy. Also, a few teachers’ stated teaching practices seem to reflect, though in a subtle way, their effort of outlining context embedded personal theories of teaching. This paper has got one significant pedagogical implication for the teacher education. Any teacher education must promote the conditions and capabilities for the present and prospective teachers for the role of theorisers in addition to develop their professional, procedural, and personal knowledge base.

Keywords: personal theories of practice, self-directed acts of professional development, self-directed acts of teaching, teacher autonomy

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Authors: Muhammad Nawaz, Waqas Ahmad

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Dimension stone is used in construction since prehistoric time; however, its use in the construction has gained significant attention for the last few decades. The present study is designed to investigate the physical and strength properties of volcanic rocks from the Kohistan Island Arc to assess their use as dimension stone. On the basis of the composition, color and texture, five varieties of andesites (MMA, PMA-1, PMA-2, CMA and FMA) and two varieties of agglomerates (AG-1 and AG-2) were identified. These were characterized in terms of their petrography (compositional and textural), physical properties (specific gravity, water absorption, porosity) and strength properties (Unconfined compressive strength and Unconfined tensile strength). Two non-destructive tests (Ultrasonic pulse velocity test and Schmidt Hammer) were conducted and the degree of polishing was evaluated. In addition, correlation analyses were carried out to establish possible relationships among these parameters. The presence of chlorite, epidote, sericite and recrystallized quartz showed the signs of low-grade metamorphism in andesites. The results showed feldspar, amphibole and quartz imparted good physical and strength properties to the samples MMA, CMA, FMA, AG1 and AG2. Whereas, the abundance of alteration products such as chlorite, sericite and epidote in PMA-1 and PMA-2 reduced the physical and strength properties. The unconfined compressive strength showed a strong correlation with ultrasonic pulse velocity, dry density, porosity and water absorption. The values of ultrasonic pulse velocity and Schmidt hammer were considerably affected by the weathering grade. The samples PMA-1 and PMA-2, due to their high water absorption and low strength values, were not recommended for use in load-bearing masonry units and outdoor applications. Whereas, the excellent properties, i.e. high strength and good polishing, the samples, FMA and MMA suggested their use as a decorative and facing stone, in the external pavement, ashlar, rubbles and load-bearing masonry units etc.

Keywords: Physico-mechanical properties, Volcanic rocks, Kohistan Island Arc, Pakistan

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Authors: Wafa Ghonaim

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Though quite fast on growth, Islamic financing at large, and its diverse instruments, is a controversial matter among scholars. This is evident from the ongoing debates on its Shariah compliance. Arguments, however, are inciting doubts and concerns among clients about its credibility, which is harming this lucrative sector. The work here investigates, particularly, some issues related to the Tawarruq instrument. The work examines the issues of linking Murabaha and Wakala contracts, the reselling of commodities to same traders, and the transfer of ownerships. The work affirms that a multi-agent smart electronic market design would facilitate Shariah compliance. The smart market exploits the rational decision-making capabilities of autonomous proxy agents that enable the clients, traders, brokers, and the bank buy and sell commodities, and manage transactions and cash flow. The smart electronic market design delivers desirable qualities that terminate the need for Wakala contracts and the reselling of commodities to the same traders. It also resolves the ownership transfer issues by allowing stakeholders to trade independently. The bank administers the smart electronic market and assures reliability of trades, transactions and cash flow. A multi-agent simulation is presented to validate the concept and processes. We anticipate that the multi-agent smart electronic market design would deliver Shariah compliance of personal financing to the aspiration of scholars, banks, traders and potential clients.

Keywords: Islamic finance, share'ah compliance, smart electronic markets design, multiagent systems

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Authors: Nataša Stojić, Mira Pucarević, Nebojša Ralević, Vojislava Bursić, Gordan Stojić

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Surface soil (0 – 10 cm) samples from 52 sampling sites along the length of railway tracks on the territory of Srem (the western part of the Autonomous Province of Vojvodina, itself part of Serbia) were collected and analyzed for 7 polychlorinated biphenyls (PCBs) in order to see how the distance from the railroad on the one hand and dump on the other hand, affect the concentration of PCBs (CPCBs) in the soil. Samples were taken at a distance of 0.03 to 4.19 km from the railway and 0.43 to 3.35 km from the landfills. For the soil extraction the Soxhlet extraction (USEPA 3540S) was used. The extracts were purified on a silica-gel column (USEPA 3630C). The analysis of the extracts was performed by gas chromatography with tandem mass spectrometry. PCBs were not detected only at two locations. Mean total concentration of PCBs for all other sampling locations was 0,0043 ppm dry weight (dw) with a range of 0,0005 to 0,0227 ppm dw. On the part of the data that were interesting for this research with statistical methods (PCA) were isolated factors that affect the concentration of PCBs. Data were also analyzed using the Pearson's chi-squared test which showed that the hypothesis of independence of CPCBs and distance from the railway can be rejected. Hypothesis of independence between CPCB and the percentage of humus in the soil can also be rejected, in contrast to dependence of CPCB and the distance from the landfill where the hypothesis of independence cannot be rejected. Based on these results can be said that railway transport is a potential source of PCBs. The next step in this research is to establish the position of transformers which are located near sampling sites as another important factor that affects the concentration of PCBs in the soil.

Keywords: GC/MS, landfill, PCB, railway, soil

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Authors: Fengmei Yao, Pengcheng Qin, Jiahua Zhang, Min Liu

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Global warming is expected to reduce the risk of low temperature stress in rice grown in temperate regions, but this impact has not been well verified by empirical studies directly on chilling injury in rice. In this study, a case study in Northeast China was presented to investigate whether the frequencies of chilling injury declined as a result of climate change, in comprehensive consideration of the potential effects from autonomous adaptation of rice production in response to climate change, such as shifts in cultivation timing and rice cultivars. It was found that frequency of total chilling injury (either delayed-growth type or sterile-type in a year) decreased but only to a limit extent in the context of climate change, mainly owing to a pronounced decrease in frequency of the delayed-growth chilling injury, while there was no overwhelming decreasing tendency for frequency of the sterile-type chilling injury, rather, it even increased considerably for some regions. If changes in cultivars had not occurred, risks of chilling injury of both types would have been much lower, specifically for the sterile-type chilling injury for avoiding deterioration in chilling sensitivity of rice cultivars. In addition, earlier planting helped lower the risk of chilling injury but still can not overweight the effects of introduction of new cultivars. It was concluded that risks of chilling injury in rice would not necessarily decrease as a result of climate change, considering the accompanying adaptation process may increase the chilling sensitivity of rice production system in a warmer climate conditions, and thus precautions should still be taken.

Keywords: chilling injury, rice, CERES-rice model, climate warming, North east China

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Authors: Evangelos Koumparoudis

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The definition of death is a deep philosophical question, and no single meaning can be ascribed to it. This essay focuses on the ontological, epistemological, and ethical aspects of death and dying in view of technological progress in information technology and biomedicine. It starts with the ad hoc 1968 Harvard committee that proposed that the criterion for the definition of death be irreversible coma and then refers to the debate over the whole brain death formula, emphasizing the integrated function of the organism and higher brain formula, taking consciousness and personality as essential human characteristics. It follows with the contribution of information technology in personalized and precision medicine and anti-aging measures aimed at life prolongation. It also touches on the possibility of the creation of human-machine hybrids and how this raises ontological and ethical issues that concern the “cyborgization” of human beings and the conception of the organism and personhood based on a post/transhumanist essence, and, furthermore, if sentient AI capable of autonomous decision-making that might even surpass human intelligence (singularity, superintelligence) deserves moral or legal personhood. Finally, there is the question as to whether death and dying should be redefined at a transcendent level, which is reinforced by already-existing technologies of “virtual after-” life and the possibility of uploading human minds. In the last section, I refer to the current (and future) applications of nanomedicine in diagnostics, therapeutics, implants, and tissue engineering as well as the aspiration to “immortality” by cryonics. The definition of death is reformulated since age and disease elimination may be realized, and the criterion of irreversibility may be challenged.

Keywords: death, posthumanism, infomedicine, nanomedicine, cryonics

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Authors: P. Moskal, T. Bednarski, P. Bialas, E. Czerwinski, A. Gajos, A. Gruntowski, D. Kaminska, L. Kaplon, G. Korcyl, P. Kowalski, T. Kozik, W. Krzemien, E. Kubicz, Sz. Niedzwiecki, M. Palka, L. Raczynski, Z. Rudy, P. Salabura, N. G. Sharma, M. Silarski, A. Slomski, J. Smyrski, A. Strzelecki, A. Wieczorek, W. Wislicki, M. Zielinski, N. Zon

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A new concept and results of the performance tests of the TOF-PET detection system developed at the Jagiellonian University will be presented. The novelty of the concept lies in employing long strips of polymer scintillators instead of crystals as detectors of annihilation quanta, and in using predominantly the timing of signals instead of their amplitudes for the reconstruction of Lines-of-Response. The diagnostic chamber consists of plastic scintillator strips readout by pairs of photo multipliers arranged axially around a cylindrical surface. To take advantage of the superior timing properties of plastic scintillators the signals are probed in the voltage domain with the accuracy of 20 ps by a newly developed electronics, and the data are collected by the novel trigger-less and reconfigurable data acquisition system. The hit-position and hit-time are reconstructed by the dedicated reconstruction methods based on the compressing sensing theory and the library of synchronized model signals. The solutions are subject to twelve patent applications. So far a time-of-flight resolution of ~120 ps (sigma) was achieved for a double-strip prototype with 30 cm field-of-view (FOV). It is by more than a factor of two better than TOF resolution achievable in current TOF-PET modalities and at the same time the FOV of 30 cm long prototype is significantly larger with respect to typical commercial PET devices. The Jagiellonian PET (J-PET) detector with plastic scintillators arranged axially possesses also another advantage. Its diagnostic chamber is free of any electronic devices and magnetic materials thus giving unique possibilities of combining J-PET with CT and J-PET with MRI for scanning the same part of a patient at the same time with both methods.

Keywords: PET-CT, PET-MRI, TOF-PET, scintillator

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Authors: Komala Arsi, Terrel Spencer, Casey M. Owens, Dan J. Donoghue, Ann M. Donoghue

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Organic poultry production is becoming increasingly popular in the United States with approximately 17% increase in the sales of organic meat and poultry in 2016. As per the National Organic Program (NOP), organic poultry production system should operate according to specific standards, including access to outdoors. In the United States, organic poultry farmers are raising both fast growing and slow growing genotypes for alternative productive systems. Even though heritage breed birds grow much slower compared to commercial breeds, many free range producers believe that they are better suited for outdoor production systems. We conducted an on-farm trial on a working pasture poultry farm to compare the performance and meat quality characteristics of a slow-growing heritage breed (Freedom Rangers, FR), and two commonly used fast growing types of chickens (Cornish cross, CC and Naked Neck, NN), raised on pasture, in side by side pens segregated by breed (n=70/breed). CC and NN group birds were reared for eight weeks whereas FR group birds were reared for 10 weeks and all the birds were commercially processed. By the end of the rearing period, the final body weight of FR group birds was significantly lower than both the fast growing genotypes (CC and NN). Both CC and NN birds showed significantly higher live weight, carcass weight as well as fillet, tender and leg yield (P < 0.05). There was no difference in the wing and rack yield among the different groups. Color of the meat was measured using CEILAB method and expressed as lightness (L), redness (a*) and yellowness (b*). The breast meat from FR birds was much redder (higher a* values) and less yellow (lesser b* values) compared to both the fast growing type of chickens (P < 0.05). Overall, fast growing genotypes produced higher carcass weight and meat yield compared to slow growing genotypes and appear to be an economical option for alternative production systems.

Keywords: fast growing chickens, meat quality, pasture, slow growing chickens

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Authors: Andres Bautista, Alicia Porras, Juan P. Casas, Maribel Silva

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The Colombian aeronautical industry has stimulated research in the mechanical behavior of materials under different loading conditions aircrafts are generally exposed during its operation. The Calima T-90 is the first military aircraft built in the country, used for primary flight training of Colombian Air Force Pilots, therefore, it may be exposed to adverse operating situations such as hard landings which cause impact loads on the aircraft that might produce the impact fatigue phenomenon. The Calima T-90 structure is mainly manufactured by composites materials generating assemblies and subassemblies of different components of it. The main method of bonding these components is by using adhesive joints. Each type of adhesive bond must be studied on its own since its performance depends on the conditions of the manufacturing process and operating characteristics. This study aims to characterize the typical adhesive joints of the aircraft under usual loads. To this purpose, the evaluation of the effect of adhesive thickness on the mechanical performance of the joint under quasi-static loading conditions, constant amplitude fatigue and cyclic impact fatigue using single lap-joint specimens will be performed. Additionally, using a double cantilever beam specimen, the influence of the thickness of the adhesive on the crack growth rate for mode I delamination failure, as a function of the critical energy release rate will be determined. Finally, an analysis of the fracture surface of the test specimens considering the mechanical interaction between the substrate (composite) and the adhesive, provide insights into the magnitude of the damage, the type of failure mechanism that occurs and its correlation with the way crack propagates under the proposed loading conditions.

Keywords: adhesive, composites, crack propagation, fatigue

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Authors: Andres Gonzalez, Adam Boies, Jacob Swanson, David Kittelson

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The concern of the indoor air quality (IAQ) has been increasing due to its risk to human health. The smoking, sweeping, and stove and stovetop use are the activities that have a major contribution to the indoor air pollution. Outdoor air pollution also affects IAQ. The most important factors over IAQ from cooking activities are the materials, fuels, foods, and ventilation. The low-cost, mobile air quality monitoring (LCMAQM) sensors, is reachable technology to assess the IAQ. This is because of the lower cost of LCMAQM compared to conventional instruments. The IAQ was assessed, using LCMAQM, during cooking activities in a University of Minnesota graduate-housing evaluating different ventilation systems. The gases measured are carbon monoxide (CO) and carbon dioxide (CO₂). The particles measured are particle matter (PM) _2.5 micrometer (µm) and lung deposited surface area (LDSA). The measurements are being conducted during April 2019 in Como Student Community Cooperative (CSCC) that is a graduate housing at the University of Minnesota. The measurements are conducted using an electric stove for cooking. The amount and type of food and oil using for cooking are the same for each measurement. There are six measurements: two experiments measure air quality without any ventilation, two using an extractor as mechanical ventilation, and two using the extractor and windows open as mechanical and natural ventilation. 3The results of experiments show that natural ventilation is most efficient system to control particles and CO₂. The natural ventilation reduces the concentration in 79% for LDSA and 55% for PM_2.5, compared to the no ventilation. In the same way, CO₂ reduces its concentration in 35%. A well-mixed vessel model was implemented to assess particle the formation and decay rates. Removal rates by the extractor were significantly higher for LDSA, which is dominated by smaller particles, than for PM_2.5, but in both cases much lower compared to the natural ventilation. There was significant day to day variation in particle concentrations under nominally identical conditions. This may be related to the fat content of the food. Further research is needed to assess the impact of the fat in food on particle generations.

Keywords: cooking, indoor air quality, low-cost sensor, ventilation

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Authors: Charlene N. T. Mfangnia, Henri Tonnang, Berge Tsanou, Jeremy Herren

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The Microsporidia MB found in the populations of anopheles is a recently discovered symbiont responsible for the Plasmodium transmission blocking. From early studies, it was established that the symbiont can be transmitted vertically and horizontally. The present study uses compartmental mathematical modelling approach to investigate the dynamics of Microsporidia transmission in the mosquito population with the mindset of establishing a mechanism for use to control malaria. Data and information obtained from laboratory experiments are used to estimate the model parameters with and without temperature dependency of mosquito traits. We carry out the mathematical analysis focusing on the equilibria states and their stability for the autonomous model. Through the modelling experiments, we are able to assess and confirm the contribution of vertical and horizontal transmission in the proliferation of Microsporidia MB in the mosquito population. In addition, the basic and target reproductions are computed, and some long-term behaviours of the model, such as the local (and global) stability of equilibrium points, are rigorously analysed and illustrated numerically. We establish the conditions responsible for the low prevalence of the symbiont-infected mosquitoes observed in nature. Moreover, we identify the male death rate, the mating rate and the attractiveness of MB-positive mosquitoes as mosquito traits that significantly influence the spread of Microsporidia MB. Furthermore, we highlight the influence of temperature in the establishment and persistence of MB-infected mosquitoes in a given area.

Keywords: microsporidia MB, vertical transmission, horizontal transmission, compartmental modelling approach, temperature-dependent mosquito traits, malaria, plasmodium-transmission blocking

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Authors: Toshifumi Hiramatsu, Satoshi Morita, Manuel Pencelli, Marta Niccolini, Matteo Ragaglia, Alfredo Argiolas

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Automation technologies for agriculture field are needed to promote labor-saving. One of the most relevant problems in automated agriculture is represented by controlling the robot along a predetermined path in presence of rough terrain or incline ground. Unfortunately, disturbances originating from interaction with the ground, such as slipping, make it quite difficult to achieve the required accuracy. In general, it is required to move within 5-10 cm accuracy with respect to the predetermined path. Moreover, lateral velocity caused by gravity on the incline field also affects slipping. In this paper, a path-tracking controller for tracked mobile robots moving on rough terrains of incline field such as vineyard is presented. The controller is composed of a disturbance observer and an adaptive controller based on the kinematic model of the robot. The disturbance observer measures the difference between the measured and the reference yaw rate and linear velocity in order to estimate slip. Then, the adaptive controller adapts “virtual” parameter of the kinematics model: Instantaneous Centers of Rotation (ICRs). Finally, target angular velocity reference is computed according to the adapted parameter. This solution allows estimating the effects of slip without making the model too complex. Finally, the effectiveness of the proposed solution is tested in a simulation environment.

Keywords: the agricultural robot, autonomous control, path-tracking control, tracked mobile robot

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Authors: M. Pawlaczyk-Łuszczyńska, T. Wszołek, A. Dudarewicz, P. Małecki, M. Kłaczyński, A. Bortkiewicz

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Human tolerance to infrasound is defined by the hearing threshold. Infrasound that cannot be heard (or felt) is not annoying and is not thought to have any other adverse or health effects. Recent research has largely confirmed earlier findings. ISO 7196:1995 recommends the use of G-weighted characteristics for the assessment of infrasound. There is a strong correlation between G-weighted SPL and annoyance perception. The aim of this study was to propose exposure limits for infrasound from wind turbines. However, only a few countries have set limits for infrasound. These limits are usually no higher than 85-92 dBG, and none of them are specific to wind turbines. Over the years, a number of studies have been carried out to determine hearing thresholds below 20 Hz. It has been recognized that 10% of young people would be able to perceive 10 Hz at around 90 dB, and it has also been found that the difference in median hearing thresholds between young adults aged around 20 years and older adults aged over 60 years is around 10 dB, irrespective of frequency. This shows that older people (up to about 60 years of age) retain good hearing in the low frequency range, while their sensitivity to higher frequencies is often significantly reduced. In terms of exposure limits for infrasound, the average hearing threshold corresponds to a tone with a G-weighted SPL of about 96 dBG. In contrast, infrasound at Lp,G levels below 85-90 dBG is usually inaudible. The individual hearing threshold can, therefore be 10-15 dB lower than the average threshold, so the recommended limits for environmental infrasound could be 75 dBG or 80 dBG. It is worth noting that the G86 curve has been taken as the threshold of auditory perception of infrasound reached by 90-95% of the population, so the G75 and G80 curves can be taken as the criterion curve for wind turbine infrasound. Finally, two assessment methods and corresponding exposure limit values have been proposed for wind turbine infrasound, i.e. method I - based on G-weighted sound pressure level measurements and method II - based on frequency analysis in 1/3-octave bands in the frequency range 4-20 Hz. Separate limit values have been set for outdoor living areas in the open countryside (Area A) and for noise sensitive areas (Area B). In the case of Method I, infrasound limit values of 80 dBG (for areas A) and 75 dBG (for areas B) have been proposed, while in the case of Method II - criterion curves G80 and G75 have been chosen (for areas A and B, respectively).

Keywords: infrasound, exposure limit, hearing thresholds, wind turbines

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Authors: Ochuko K. Overen, Golden Makaka, Edson L. Meyer, Sampson Mamphweli

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Low-cost housing provided for people with small incomes in South Africa are characterized by poor thermal performance. This is due to inferior craftsmanship with no regard to energy efficient design during the building process. On average, South African households spend 14% of their total monthly income on energy needs, in particular space heating; which is higher than the international benchmark of 10% for energy poverty. Adopting energy efficient passive solar design strategies and superior thermal building materials can create a stable thermal comfort environment indoors. Thereby, reducing energy consumption for space heating. The aim of this study is to analyse the thermal behaviour of a low-cost house integrated with passive solar design features. A low-cost passive solar house with superstructure fly ash brick walls was designed and constructed in Somerset East, South Africa. Indoor and outdoor meteorological parameters of the house were monitored for a period of one year. The ASTM E741-11 Standard was adopted to perform ventilation test in the house. In summer, the house was found to be thermally comfortable for 66% of the period monitored, while for winter it was about 79%. The ventilation heat flow rate of the windows and doors were found to be 140 J/s and 68 J/s, respectively. Air leakage through cracks and openings in the building envelope was 0.16 m3/m2h with a corresponding ventilation heat flow rate of 24 J/s. The indoor carbon dioxide concentration monitored overnight was found to be 0.248%, which is less than the maximum range limit of 0.500%. The prediction percentage dissatisfaction of the house shows that 86% of the occupants will express the thermal satisfaction of the indoor environment. With a good operation of the house, it can create a well-ventilated, thermal comfortable and nature luminous indoor environment for the occupants. Incorporating passive solar design in low-cost housing can be one of the long and immediate solutions to the energy crisis facing South Africa.

Keywords: energy efficiency, low-cost housing, passive solar design, rural development, thermal comfort

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Authors: N. Maksimentseva

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The issue of public administration in subsoil use, renewal and protection is of high importance for Ukraine since it is strongly linked to energy security of the state as well as it shall facilitate the people of Ukraine to efficiently implement its propitiatory rights towards natural resources and redistribution of national wealth. As it is stipulated in the Article 11 of the Subsoil Code of Ukraine (the Code) the authorities that administer the industry are limited to central executive bodies and local governments. In particular, it is stipulated in the Code that the Ukraine’s Cabinet of Ministers carries out public administration in geological exploration, production and protection of subsoil. Other state bodies of public administration include central public authority responsible for state environmental protection policies; central public authority in charge of implementation of state geological exploration and efficient subsoil use policies; central authority in charge of state health and safety control policies. There are also public authorities in the Autonomous Republic of Crimea; local executive bodies and other state authorities and local self-government authorities in compliance with laws of Ukraine. This article is devoted to the analysis of the legal relations in the area of public administration of subsoil use, renewal and protection in Ukraine. The main approaches to study the essence of legal relations in the named area as well as its tasks, functions and methods are analyzed. It is concluded in this article that legal relationship in the field of public administration of subsoil use, renewal and protection is characterized by specifics of its task (development of natural resources).

Keywords: legal relations, public administration, subsoil code of Ukraine, subsoil use, renewal and protection

Procedia PDF Downloads 328

Authors: Saidou Hassidou, Laminou Ary Mahaman Moustapha

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Uncontrolled urbanization of African cities, plus the lack of municipal waste management services in these cities, generate landscapes become places of multiple and varied interactions between health and environment. In this sense, under strong urban growth in a context of sub-equipment sanitation, the city of Maradi doesn’t escape to this situation which results in the spread of pollution (release of unpleasant odors, proliferation of mosquitoes) and many diseases posing multiple health problems. Our study focuses only on liquid waste especially domestic wastewater. To study the different domestic wastewater management options in the town of Maradi, a survey was conducted among 340 households in 17 districts. We note in most cases a crucial of waste management infrastructure (drainage and wastewater treatment) at the city. Thus, only the individual sanitation facilities are used. In the town of Maradi, in addition to the storm drains, there are, in old districts, ditches that discharge wastewater and unfortunately end up in rivers without treatment. Domestic wastewater total production is estimated at 86,761.28 m3 per day. This water is mostly from laundry activities, bathing, dishes, and is discharged in large part through the streets, by more than 60% of households. Also, pit emptying is performed at 39.11% by the vehicle Peugeot tank. The quality of service rendered by an actor is very important to encourage households to join. Existing autonomous sanitation facilities are poorly designed and poorly maintained. Fecal sludge is dumped in a hole near saturated latrines; this work is mainly done by manual scavengers or dumped in fields or on nearby vacant land concessions.

Keywords: management, urban wastewater, domestic wastewater, Maradi, Niger

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Authors: V. G. Cappellesso, D. M. G. da Silva, J. A. Arndt, N. dos Santos Petry, A. B. Masuero, D. C. C. Dal Molin

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Concrete elements are subject to cracking, which can be an access point for deleterious agents that can trigger pathological manifestations reducing the service life of these structures. Finding ways to minimize or eliminate the effects of this aggressive agents’ penetration, such as the sealing of these cracks, is a manner of contributing to the durability of these structures. The cementitious self-healing phenomenon can be classified in two different processes. The autogenous self-healing that can be defined as a natural process in which the sealing of this cracks occurs without the stimulation of external agents, meaning, without different materials being added to the mixture, while on the other hand, the autonomous seal-healing phenomenon depends on the insertion of a specific engineered material added to the cement matrix in order to promote its recovery. This work aims to evaluate the autogenous self-healing of concretes produced with different water/cement ratios and exposed to wet/dry cycles, considering two ages of crack openings, 3 days and 28 days. The self-healing phenomenon was evaluated using two techniques: crack healing measurement using ultrasonic waves and image analysis performed with an optical microscope. It is possible to observe that by both methods, it possible to observe the self-healing phenomenon of the cracks. For young ages of crack openings and lower water/cement ratios, the self-healing capacity is higher when compared to advanced ages of crack openings and higher water/cement ratios. Regardless of the crack opening age, these concretes were found to stabilize the self-healing processes after 80 days or 90 days.

Keywords: sealf-healing, autogenous, water/cement ratio, curing cycles, test methods

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Authors: George Mahalu

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The Chua diode has been configured over time in various ways, using electronic structures like operational amplifiers (AOs) or devices with gas or semiconductors. When discussing the use of semiconductor devices, tunnel diodes (Esaki diodes) are most often considered, and more recently, transistorized configurations such as lambda diodes. The paperwork proposed here uses in the modeling a lambda diode type configuration consisting of two junction field effect transistors (JFET). The original scheme is created in the MULTISIM electronic simulation environment and is analyzed in order to identify the conditions for the appearance of evolutionary unpredictability specific to nonlinear dynamic systems with chaos-induced behavior. The chaotic deterministic oscillator is one autonomous type, a fact that places it in the class of Chua’s type oscillators, the only significant and most important difference being the presence of a nonlinear device like the one mentioned structure above. The chaotic behavior is identified both by means of strange attractor-type trajectories and visible during the simulation and by highlighting the hypersensitivity of the system to small variations of one of the input parameters. The results obtained through simulation and the conclusions drawn are useful in the further research of ways to implement such constructive electronic solutions in theoretical and practical applications related to modern small signal amplification structures, to systems for encoding and decoding messages through various modern ways of communication, as well as new structures that can be imagined both in modern neural networks and in those for the physical implementation of some requirements imposed by current research with the aim of obtaining practically usable solutions in quantum computing and quantum computers.

Keywords: chua, diode, memristor, chaos

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Authors: Klara Smith-Etxeberria

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main goal of this study was to analyze the predictive ability of some variables associated with the parental divorce process alongside attachment history with parents on both, mother-child and father-child relationship quality. Our sample consisted of 173 undergraduate and vocational school students from the Autonomous Community of the Basque Country. All of them belonged to a divorced family. Results showed that adequate maternal strategies during the divorce process (e.g.: stable, continuous and positive role as a mother) was the variable with greater predictive ability on mother-child relationships quality. In addition, secure attachment history with mother also predicted positive mother-child relationships. On the other hand, father-child relationship quality was predicted by adequate paternal strategies during the divorce process, such as his stable, continuous and positive role as a father, along with not badmouthing the mother and promoting good mother-child relationships. Furthermore, paternal negative emotional state due to divorce was positively associated with father-child relationships quality, and both, history of attachment with mother and with father predicted father-child relationships quality. In conclusion, our data indicate that both, paternal and maternal strategies for children´s adequate adjustment during the divorce process influence on mother-child and father-child relationships quality. However, these results suggest that paternal strategies during the divorce process have a greater predictive ability on father-child relationships quality, whereas maternal positive strategies during divorce determine positive mother-child relationships among young adults.

Keywords: father-child relationships quality, mother-child relationships quality, parental divorce process, young adulthood

Procedia PDF Downloads 241