Search results for: optical force

Authors: Pradip Choudhury, Tapobrata Sanyal

Abstract:

Effectiveness of Jute Geotextiles (JGT) in hill slope management now stands substantiated. The reasons of its efficacy are attributed to its bio-degradability, hygroscopic property and its thickness. Usually open weave JGT is used for slope management. Thickness of JGT helps in reducing the velocity of surface run-off, thus curbing the extent of migration of soil particles detached as a result of kinetic energy of rain-drops and also of wind effects. Initially JGT acts as cover of the surface of slope thus protect movement of loose soil particles. Hygroscopic property of jute effects overland storage of the flow. JGT acts as mulch and creates a congenial micro-climate that fosters quick growth of vegetation on bio-degradation. In fact JGT plays an important role in bio-remediation of slope-erosion problems. Considering the environmental aftermath, JGT is the preferred option in developed countries for surface soil conservation against erosion. In India JGT has not been tried in low temperature zones at high altitudes where temperature goes below the freezing point (even below - 25° Celsius). The behavior of JGT in such low-temperature zones is not precisely known. The 16th BRTF of Project Himank of Border Roads Organization (BRO) has recently taken the initiative to try two varieties of JGT , ie, 292 gsm and 500 gsm at two different places for hill slope management in Leh, a high altitude place of about 2,660 mtrs and 4900 mtrs above MSL respectively in Jammu & Kashmir where erosion is caused more as a result of rapid movement of sand particles due to high wind (wind erosion. Soil particles of the region formed naturally by weathering of fragile rocks are usually loosely bonded (non-cohesive), undergo dissociation with the rise in wind force and kinetic energy of rain drops and are blown away by wind. Open weave JGT interestingly was observed to contain the dissociated soil particles within its pores and lend stability the affected soil mass to a great extent thus preventing its movement by extraneous agents such as wind. The paper delineates about climatic factors, type of JGT used and the prevailing site conditions with an attempt to analyze the mechanism of functioning of JGT in low temperature zones.

Keywords: climate, erosion, jutegeotextile, stabilize

Procedia PDF Downloads 410

Authors: Pornthep Rachnavy

Abstract:

The purpose of this paper is twofold. First, we believe that there are a significant relationship between sculling angle and sculling style among adaptive rowing. Second, we introduce a methodology used for adaptive rowing, namely simulation, to identify effectiveness of adaptive rowing. For our study we simulate the arms only single scull of adaptive rowing. The method for rowing fastest under the 1000 meter was investigated by study sculling angle using the simulation modeling. A simulation model of a rowing system was developed using the Matlab software package base on equations of motion consist of many variation for moving the boat such as oars length, blade velocity and sculling style. The boat speed, power and energy consumption on the system were compute. This simulation modeling can predict the force acting on the boat. The optimum sculling angle was performing by computer simulation for compute the solution. Input to the model are sculling style of each rower and sculling angle. Outputs of the model are boat velocity at 1000 meter. The present study suggests that the optimum sculling angle exist depends on sculling styles. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the first style is -57.00 and 22.0 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the second style is -57.00 and 22.0 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the third style is -51.57 and 28.65 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the fourth style is -45.84 and 34.38 degree. A theoretical simulation for rowing has been developed and presented. The results suggest that it may be advantageous for the rowers to select the sculling angles proper to sculling styles. The optimum sculling angles of the rower depends on the sculling styles made by each rower. The investigated of this paper can be concludes in three directions: 1;. There is the optimum sculling angle in arms only single scull of adaptive rowing. 2. The optimum sculling angles depend on the sculling styles. 3. Computer simulation of rowing can identify opportunities for improving rowing performance by utilizing the kinematic description of rowing. The freedom to explore alternatives in speed, thrust and timing with the computer simulation will provide the coach with a tool for systematic assessments of rowing technique In addition, the ability to use the computer to examine the very complex movements during rowing will help both the rower and the coach to conceptualize the components of movements that may have been previously unclear or even undefined.

Keywords: simulation, sculling, adaptive, rowing

Procedia PDF Downloads 445

Authors: Mario P. Walker, Masaaki Okuma

Abstract:

Ships are subjected to motions which can disrupt on-board operations and damage equipment. Roll motion, in particular, is of great interest due to low damping conditions which may lead to capsizing. Therefore finding ways to reduce this motion is important in ship designs. Several techniques have been investigated to reduce rolling. These include the commonly used anti-roll tanks, fin stabilizers and bilge keels. However, these systems are not without their challenges. For example, water-flow in anti-roll tanks creates complications, and for fin stabilizers and bilge keels, an extremely large size is required to produce any significant damping creating operational challenges. Additionally, among these measures presented above only anti-roll tanks are effective in zero forward motion of the vessels. This paper proposes and investigates a method to reduce rolling by inducing Coriolis effect using water-flow in the radial direction. Motion in the radial direction of a rolling structure will induce Coriolis force and, depending on the direction of flow will either amplify or attenuate the structure. The system is modelled with two degrees of freedom, having rotational motion for parametric rolling and radial motion of the water-flow. Equations of motion are derived and investigated. Numerical examples are analyzed in detail. To demonstrate applicability parameters from a Ro-Ro vessel are used as extensive research have been conducted on these over the years. The vessel is investigated under free and forced roll conditions. Several models are created using various masses, heights, and velocities of water-flow at a given time. The proposed system was found to produce substantial roll reduction which increases with increase in any of the parameters varied as stated above, with velocity having the most significant effect. The proposed system provides a simple approach to reduce ship rolling. Water-flow control is very simple as the water flows in only one direction with constant velocity. Only needing to control the time at which the system should be turned on or off. Furthermore, the proposed system is effective in both forward and zero forward motion of the ship, and provides no hydrodynamic drag. This is a starting point for designing an effective and practical system. For this to be a viable approach further investigations are needed to address challenges that present themselves.

Keywords: Coriolis effect, damping, rolling, water-flow

Procedia PDF Downloads 437

Authors: Robin Anderson, Elizabeth Latham, David Nisbet

Abstract:

Propagation and dissemination of antimicrobial resistant and pathogenic microbes from spoiled silages and composts represents a serious public health threat to humans and animals. In the present study, the antimicrobial activity of the short chain nitro-compound, 2-nitro-1-propanol (9 mM) as well as the medium chain fatty acid, lauric acid, and its glycerol monoester, monolaurin, (each at 25 and 17 µmol/mL, respectfully) were investigated against select pathogenic and multi-drug resistant antimicrobial resistant Gram-positive bacteria common to spoiled silages and composts. In an initial study, we found that growth rates of a multi-resistant Enterococcus faecalis (expressing resistance against erythromycin, quinupristin/dalfopristin and tetracycline) and Staphylococcus aureus strain 12600 (expressing resistance against erythromycin, linezolid, penicillin, quinupristin/dalfopristin and vancomycin) were more than 78% slower (P < 0.05) by 2-nitro-1-propanol treatment during culture (n = 3/treatment) in anaerobically prepared ½ strength Brain Heart Infusion broth at 37oC when compared to untreated controls (0.332 ± 0.04 and 0.108 ± 0.03 h-1, respectively). The growth rate of 2-nitro-1-propanol-treated Listeria monocytogenes was also decreased by 96% (P < 0.05) when compared to untreated controls cultured similarly (0.171 ± 0.01 h-1). Maximum optical densities measured at 600 nm were lower (P < 0.05) in 2-nitro-1-propanol-treated cultures (0.053 ± 0.01, 0.205 ± 0.02 and 0.041 ± 0.01, respectively) than in untreated controls (0.483 ± 0.02, 0.523 ± 0.01 and 0.427 ± 0.01, respectively) for E. faecalis, S. aureus and L. monocytogenes, respectively. When tested against mixed microbial populations during anaerobic 24 h incubation of spoiled silage, significant effects of treatment with 1 mg 2-nitro-1-propanol (approximately 9.5 µmol/g) or 5 mg lauric acid/g (approximately 25 µmol/g) on populations of wildtype Enterococcus and Listeria were not observed. Mixed populations treated with 5 mg monolaurin/g (approximately 17 µmol/g) had lower (P < 0.05) viable cell counts of wildtype enterococci than untreated controls after 6 h incubation (2.87 ± 1.03 versus 5.20 ± 0.25 log10 colony forming units/g, respectively) but otherwise significant effects of monolaurin were not observed. These results reveal differential susceptibility of multi-drug resistant enterococci and staphylococci as well as L. monocytogenes to the inhibitory activity of 2-nitro-1-propanol and the medium chain fatty acid, lauric acid and its glycerol monoester, monolaurin. Ultimately, these results may lead to improved treatment technologies to preserve the microbiological safety of silages and composts.

Keywords: 2-nitro-1-propanol, lauric acid, monolaurin, gram positive bacteria

Procedia PDF Downloads 87

Authors: Wei Liu, Shuquan Wang, Yang Gao

Abstract:

Microgravity Science Experiment Rack (MSER) will be onboard TianHe (TH) spacecraft planned to be launched in 2018. TH is one module of Chinese Space Station. Microgravity Vibration Isolation System (MVIS), which is MSER’s core part, is used to isolate disturbance from TH and provide high-level microgravity for science experiment payload. MVIS is two stage vibration isolation system, consisting of Follow Unit (FU) and Experiment Support Unit (ESU). FU is linked to MSER by umbilical cables, and ESU suspends within FU and without physical connection. The FU’s position and attitude relative to TH is measured by binocular vision measuring system, and the acceleration and angular velocity is measured by accelerometers and gyroscopes. Air-jet thrusters are used to generate force and moment to control FU’s motion. Measurement module on ESU contains a set of Position-Sense-Detectors (PSD) sensing the ESU’s position and attitude relative to FU, accelerometers and gyroscopes sensing ESU’s acceleration and angular velocity. Electro-magnetic actuators are used to control ESU’s motion. Firstly, the linearized equations of FU’s motion relative to TH and ESU’s motion relative to FU are derived, laying the foundation for control system design and simulation analysis. Subsequently, two control schemes are proposed. One control scheme is that ESU tracks FU and FU tracks TH, shorten as E-F-T. The other one is that FU tracks ESU and ESU tracks TH, shorten as F-E-T. In addition, motion spaces are constrained within ±15 mm、±2° between FU and ESU, and within ±300 mm between FU and TH or between ESU and TH. A Proportional-Integrate-Differentiate (PID) controller is designed to control FU’s position and attitude. ESU’s controller includes an acceleration feedback loop and a relative position feedback loop. A Proportional-Integrate (PI) controller is designed in the acceleration feedback loop to reduce the ESU’s acceleration level, and a PID controller in the relative position feedback loop is used to avoid collision. Finally, simulations of E-F-T and F-E-T are performed considering variety uncertainties, disturbances and motion space constrains. The simulation results of E-T-H showed that control performance was from 0 to -20 dB for vibration frequency from 0.01 to 0.1 Hz, and vibration was attenuated 40 dB per ten octave above 0.1Hz. The simulation results of T-E-H showed that vibration was attenuated 20 dB per ten octave at the beginning of 0.01Hz.

Keywords: microgravity science experiment rack, microgravity vibration isolation system, PID control, vibration isolation performance

Procedia PDF Downloads 148

Authors: Zahra Mila Elmi, Mahsa Khanekheshi

Abstract:

Almost half of the population and potential manpower in the country and rural areas are women. Manpower especially educated people, plays an important role in the production and economic growth. Also, the potential of rural areas to create employment should not be overlooked. In this research, the effects of socio-economic and demographic factors on women's economic participation in rural areas of Iran's provinces will be studied. Therefore, this study was performed by using the results of the rural households income and expenditure surveys -has been taken in 2016- in the framework of pseudo panel data. This study used the logit model and the maximum likelihood method to study the rural women's participation, with 28,265 observations. Results show the inverted U-shaped relationship between age and the probability of female participation; In other words, young women are more likely to participate in labor markets more than the other groups. Divorced and single woman has more chance of participation in comparison with who was being married. With increasing the divorce rate and singleness in Iran, economic policymakers must provide appropriate solutions for this challenge in the coming years. On the base of the results, being a student and the presence of an infant under the age of 6 in the household has a negative effect on the possibility of women's participation in the labor market. The women's education level has a U-shaped relationship with their participation rate. Illiteracy and high education have a strong positive effect on the economic participation of rural women. This shows the dual labor market for women in Iran. Illiterate women are attracted to service jobs, and educated woman are more attracted to education and health jobs. Increasing household income has a small but positive and significant effect on the probability of rural female participation. In the overlook, due to the frequency of the women population in the age group of 25 to 35 years, and more willingness of women in the age 35 to 44 years to participate in the labor market, and studying ofa significant portion of the rural women, the increase of rural female participation is expected in the years ahead. Thus, it is expected policy maker to create new job opportunities for the employment of educated women and take the necessary plan to improve the current situation for women.

Keywords: female participation rate, rural area, provincial data, pseudo-panel data method

Procedia PDF Downloads 72

Authors: Nothando Gwazani, K. R. Marembo

Abstract:

An increase in the atmospheric concentration of carbon dioxide (CO₂) from fossil fuel and land use change necessitates identification of strategies for mitigating threats associated with global warming. Oceans are insufficient to offset the accelerating rate of carbon emission. However, the challenges of oceans as a source of reducing carbon footprint can be effectively overcome by the storage of carbon in terrestrial carbon sinks. The gases with special optical properties that are responsible for climate warming include carbon dioxide (CO₂), water vapors, methane (CH₄), nitrous oxide (N₂O), nitrogen oxides (NOₓ), stratospheric ozone (O₃), carbon monoxide (CO) and chlorofluorocarbons (CFC’s). Amongst these, CO₂ plays a crucial role as it contributes to 50% of the total greenhouse effect and has been linked to climate change. Because plants act as carbon sinks, interest in terrestrial carbon sequestration has increased in an effort to explore opportunities for climate change mitigation. Removal of carbon from the atmosphere is a topical issue that addresses one important aspect of an overall strategy for carbon management namely to help mitigate the increasing emissions of CO₂. Thus, terrestrial ecosystems have gained importance for their potential to sequester carbon and reduce carbon sink in oceans, which have a substantial impact on the ocean species. Field data and electromagnetic spectrum bands were analyzed using ArcGIS 10.2, QGIS 2.8 and ERDAS IMAGINE 2015 to examine the vegetation distribution. Satellite remote sensing data coupled with Normalized Difference Vegetation Index (NDVI) was employed to assess future potential changes in vegetation distributions in Eastern Cape Province of South Africa. The observed 5-year interval analysis examines the amount of carbon absorbed using vegetation distribution. In 2015, the numerical results showed low vegetation distribution, therefore increased the acidity of the oceans and gravely affected fish species and corals. The outcomes suggest that the study area could be effectively utilized for carbon sequestration so as to mitigate ocean acidification. The vegetation changes measured through this investigation suggest an environmental shift and reduced vegetation carbon sink, and that threatens biodiversity and ecosystem. In order to sustain the amount of carbon in the terrestrial ecosystems, the identified ecological factors should be enhanced through the application of good land and forest management practices. This will increase the carbon stock of terrestrial ecosystems thereby reducing direct loss to the atmosphere.

Keywords: remote sensing, vegetation dynamics, carbon sequestration, terrestrial carbon sink

Procedia PDF Downloads 128

Authors: Bertalan Jillek, Péter Szabó, Judit Kopniczky, István Szabó, Balázs Patczai, Kinga Turzó

Abstract:

Hip and knee prostheses are one of the most frequently used medical implants, that can significantly improve patients’ quality of life. Long term success and biointegration of these prostheses depend on several factors, like bulk and surface characteristics, construction and biocompatibility of the material. The applied surgical technique, the general health condition and life-quality of the patient are also determinant factors. Medical devices used in orthopedic surgeries have different surfaces depending on their function inside the human body. Surface roughness of these implants determines the interaction with the surrounding tissues. Numerous modifications have been applied in the recent decades to improve a specific property of an implant. Our goal was to compare the surface characteristics of typical implant materials used in orthopedic surgery and traumatology. Morphological and chemical structure of Vortex plate anodized titanium, cemented THR (total hip replacement) stem high nitrogen REX steel (SS), uncemented THR stem and cup titanium (Ti) alloy with titanium plasma spray coating (TPS), cemented cup and uncemented acetabular liner HXL and UHMWPE and TKR (total knee replacement) femoral component CoCrMo alloy (Sanatmetal Ltd, Hungary) discs were examined. Visualization and elemental analysis were made by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Surface roughness was determined by atomic force microscopy (AFM) and profilometry. SEM and AFM revealed the morphological and roughness features of the examined materials. TPS Ti presented the highest Ra value (25 ± 2 μm, followed by CoCrMo alloy (535 ± 19 nm), Ti (227 ± 15 nm) and stainless steel (170 ± 11 nm). The roughness of the HXL and UHMWPE surfaces was in the same range, 147 ± 13 nm and 144 ± 15 nm, respectively. EDS confirmed typical elements on the investigated prosthesis materials: Vortex plate Ti (Ti, O, P); TPS Ti (Ti, O, Al); SS (Fe, Cr, Ni, C) CoCrMo (Co, Cr, Mo), HXL (C, Al, Ni) and UHMWPE (C, Al). The results indicate that the surface of prosthesis materials have significantly different features and the applied investigation methods are suitable for their characterization. Contact angle measurements and in vitro cell culture testing are further planned to test their surface energy characteristics and biocompatibility.

Keywords: morphology, PE, roughness, titanium

Procedia PDF Downloads 104

Authors: Siavash Ostovar

Abstract:

The Iranian national Law on the Ramsar Convention (officially known as the Convention of International Wetlands and Aquatic Birds' Habitat Wetlands) was approved by the Senate and became a law in 1974 after the ratification of the National Council. There are other national laws with the aim of preservation of environment in the country. However, Lake Urmia which is declared a wetland of international importance by the Ramsar Convention in 1971 and designated a UNESCO Biosphere Reserve in 1976 is now at the brink of total disappearance due mainly to the climate change, water mismanagement, dam construction, and agricultural deficiencies. Lake Urmia is located in the north western corner of Iran. It is the third largest salt water lake in the world and the largest lake in the Middle East. Locally, it is designated as a National Park. It is, indeed, a unique lake both nationally and internationally. This study investigated how effective the national legal regulation of the ecosystem of Lake Urmia is in Iran. To do so, the Iranian national laws as Enforcement of Ramsar Convention in the country including three nationally established laws of (i) Five sets of laws for the programme of economic, social and cultural development of Islamic Republic of Iran, (ii) The Iranian Penal Code, (iii) law of conservation, restoration and management of the country were investigated. Using black letter law methods, it was revealed that (i) regarding the national five sets of laws; the benchmark to force the implementation of the legislations and policies is not set clearly. In other words, there is no clear guarantee to enforce these legislations and policies at the time of deviation and violation; (ii) regarding the Penal Code, there is lack of determining the environmental crimes, determining appropriate penalties for the environmental crimes, implementing those penalties appropriately, monitoring and training programmes precisely; (iii) regarding the law of conservation, restoration and management, implementation of this regulation is adjourned to preparation, announcement and approval of several categories of enactments and guidelines. In fact, this study used a national environmental catastrophe caused by drying up of Lake Urmia as an excuse to direct the attention to the weaknesses of the existing national rules and regulations. Finally, as we all depend on the natural world for our survival, this study recommended further research on every environmental issue including the Lake Urmia.

Keywords: conservation, environmental law, Lake Urmia, national laws, Ramsar Convention, water management, wetlands

Procedia PDF Downloads 183

Authors: P. Barreto, A. Guevara, V. Ibujes

Abstract:

In this study, the removal of arsenic from synthetic solutions and natural water from Papallacta Lagoon was evaluated, by using the rhizofiltration method with terrestrial and aquatic plant species. Ecuador is a country of high volcanic activity, that is why most of water sources come from volcanic glaciers. Therefore, it is necessary to find new, affordable and effective methods for treating water. The water from Papallacta Lagoon shows levels from 327 µg/L to 803 µg/L of arsenic. The evaluation for the removal of arsenic began with the selection of 16 different species of terrestrial and aquatic plants. These plants were immersed to solutions of 4500 µg/L arsenic concentration, for 48 hours. Subsequently, 3 terrestrial species and 2 aquatic species were selected based on the highest amount of absorbed arsenic they showed, analyzed by plasma optical emission spectrometry (ICP-OES), and their best capacity for adaptation into the arsenic solution. The chosen terrestrial species were cultivated from their seed with hydroponics methods, using coconut fiber and polyurethane foam as substrates. Afterwards, the species that best adapted to hydroponic environment were selected. Additionally, a control of the development for the selected aquatic species was carried out using a basic nutrient solution to provide the nutrients that the plants required. Following this procedure, 30 plants from the 3 types of species selected were exposed to a synthetic solution with levels of arsenic concentration of 154, 375 and 874 µg/L, for 15 days. Finally, the plant that showed the highest level of arsenic absorption was placed in 3 L of natural water, with arsenic levels of 803 µg/L. The plant laid in the water until it reached the desired level of arsenic of 10 µg/L. This experiment was carried out in a total of 30 days, in which the capacity of arsenic absorption of the plant was measured. As a result, the five species initially selected to be used in the last part of the evaluation were: sunflower (Helianthus annuus), clover (Trifolium), blue grass (Poa pratensis), water hyacinth (Eichhornia crassipes) and miniature aquatic fern (Azolla). The best result of arsenic removal was showed by the water hyacinth with a 53,7% of absorption, followed by the blue grass with 31,3% of absorption. On the other hand, the blue grass was the plant that best responded to the hydroponic cultivation, by obtaining a germination percentage of 97% and achieving its full growth in two months. Thus, it was the only terrestrial species selected. In summary, the final selected species were blue grass, water hyacinth and miniature aquatic fern. These three species were evaluated by immersing them in synthetic solutions with three different arsenic concentrations (154, 375 and 874 µg/L). Out of the three plants, the water hyacinth was the one that showed the highest percentages of arsenic removal with 98, 58 and 64%, for each one of the arsenic solutions. Finally, 12 plants of water hyacinth were chosen to reach an arsenic level up to 10 µg/L in natural water. This significant arsenic concentration reduction was obtained in 5 days. In conclusion, it was found that water hyacinth is the best plant to reduce arsenic levels in natural water.

Keywords: arsenic, natural water, plant species, rhizofiltration, synthetic solutions

Procedia PDF Downloads 107

Authors: I. Nitoi, P. Oancea, M. Raileanu, M. Crisan, L. Constantin, I. Cristea

Abstract:

Hazardous organic compounds like nitroaromatics are frequently found in chemical and petroleum industries discharged effluents. Due to their bio-refractory character and high chemical stability cannot be efficiently removed by classical biological or physical-chemical treatment processes. In the past decades, semiconductor photocatalysis has been frequently applied for the advanced degradation of toxic pollutants. Among various semiconductors titania was a widely studied photocatalyst, due to its chemical inertness, low cost, photostability and nontoxicity. In order to improve optical absorption and photocatalytic activity of TiO2 many attempts have been made, one feasible approach consists of doping oxide semiconductor with metal. The degradation of dinitrobenzene (DNB) and dinitrotoluene (DNT) from aqueous solution under UVA-VIS irradiation using heavy metal (0.5% Fe, 1%Co, 1%Ni ) doped titania was investigated. The photodegradation experiments were carried out using a Heraeus laboratory scale UV-VIS reactor equipped with a medium-pressure mercury lamp which emits in the range: 320-500 nm. Solutions with (0.34-3.14) x 10-4 M pollutant content were photo-oxidized in the following working conditions: pH = 5-9; photocatalyst dose = 200 mg/L; irradiation time = 30 – 240 minutes. Prior to irradiation, the photocatalyst powder was added to the samples, and solutions were bubbled with air (50 L/hour), in the dark, for 30 min. Dopant type, pH, structure and initial pollutant concentration influence on the degradation efficiency were evaluated in order to set up the optimal working conditions which assure substrate advanced degradation. The kinetics of nitroaromatics degradation and organic nitrogen mineralization was assessed and pseudo-first order rate constants were calculated. Fe doped photocatalyst with lowest metal content (0.5 wt.%) showed a considerable better behaviour in respect to pollutant degradation than Co and Ni (1wt.%) doped titania catalysts. For the same working conditions, degradation efficiency was higher for DNT than DNB in accordance with their calculated adsobance constants (Kad), taking into account that degradation process occurs on catalyst surface following a Langmuir-Hinshalwood model. The presence of methyl group in the structure of DNT allows its degradation by oxidative and reductive pathways, while DNB is converted only by reductive route, which also explain the highest DNT degradation efficiency. For highest pollutant concentration tested (3 x 10-4 M), optimum working conditions (0.5 wt.% Fe doped –TiO2 loading of 200 mg/L, pH=7 and 240 min. irradiation time) assures advanced nitroaromatics degradation (ηDNB=89%, ηDNT=94%) and organic nitrogen mineralization (ηDNB=44%, ηDNT=47%).

Keywords: hazardous organic compounds, irradiation, nitroaromatics, photocatalysis

Procedia PDF Downloads 295

Authors: Yudo Prasetyo, Hana Sugiastu Firdaus, Diyanah Diyanah

Abstract:

The phenomenon of the lack of clean water supply in several big cities in Indonesia is a major problem in the development of urban areas. Moreover, in the city of Semarang, the population density and growth of physical development is very high. Continuous and large amounts of underground water (aquifer) exposure can result in a drastically aquifer supply declining in year by year. Especially, the intensity of aquifer use in the fulfilment of household needs and industrial activities. This is worsening by the land subsidence phenomenon in some areas in the Semarang city. Therefore, special research is needed to know the spatial correlation of the impact of decreasing aquifer capacity on the land subsidence phenomenon. This is necessary to give approve that the occurrence of land subsidence can be caused by loss of balance of pressure on below the land surface. One method to observe the correlation pattern between the two phenomena is the application of remote sensing technology based on radar and optical satellites. Implementation of Differential Interferometric Synthetic Aperture Radar (DINSAR) or Small Baseline Area Subset (SBAS) method in SENTINEL-1A satellite image acquisition in 2014-2017 period will give a proper pattern of land subsidence. These results will be spatially correlated with the aquifer-declining pattern in the same time period. Utilization of survey results to 8 monitoring wells with depth in above 100 m to observe the multi-temporal pattern of aquifer change capacity. In addition, the pattern of aquifer capacity will be validated with 2 underground water cavity maps from observation of ministries of energy and natural resources (ESDM) in Semarang city. Spatial correlation studies will be conducted on the pattern of land subsidence and aquifer capacity using overlapping and statistical methods. The results of this correlation will show how big the correlation of decrease in underground water capacity in influencing the distribution and intensity of land subsidence in Semarang city. In addition, the results of this study will also be analyzed based on geological aspects related to hydrogeological parameters, soil types, aquifer species and geological structures. The results of this study will be a correlation map of the aquifer capacity on the decrease in the face of the land in the city of Semarang within the period 2014-2017. So hopefully the results can help the authorities in spatial planning and the city of Semarang in the future.

Keywords: aquifer, differential interferometric synthetic aperture radar (DINSAR), land subsidence, small baseline area subset (SBAS)

Procedia PDF Downloads 165

Authors: Sulalit Bandyopadhyay, Muhammad Awais Ashfaq Alvi, Anuvansh Sharma, Wilhelm R. Glomm

Abstract:

Release of drugs from nanogels and nanogel-based systems can occur under the influence of external stimuli like temperature, pH, magnetic fields and so on. pNIPAm-AAc nanogels respond to the combined action of both temperature and pH, the former being mostly determined by hydrophilic-to-hydrophobic transitions above the volume phase transition temperature (VPTT), while the latter is controlled by the degree of protonation of the carboxylic acid groups. These nanogels based systems are promising candidates in the field of drug delivery. Combining nanogels with magneto-plasmonic nanoparticles (NPs) introduce imaging and targeting modalities along with stimuli-response in one hybrid system, thereby incorporating multifunctionality. Fe@Au core-shell NPs possess optical signature in the visible spectrum owing to localized surface plasmon resonance (LSPR) of the Au shell, and superparamagnetic properties stemming from the Fe core. Although there exist several synthesis methods to control the size and physico-chemical properties of pNIPAm-AAc nanogels, yet, there is no comprehensive study that highlights the dependence of incorporation of one or more layers of NPs to these nanogels. In addition, effective determination of volume phase transition temperature (VPTT) of the nanogels is a challenge which complicates their uses in biological applications. Here, we have modified the swelling-collapse properties of pNIPAm-AAc nanogels, by combining with Fe@Au NPs using different solution based methods. The hydrophilic-hydrophobic transition of the nanogels above the VPTT has been confirmed to be reversible. Further, an analytical method has been developed to deduce the average VPTT which is found to be 37.3°C for the nanogels and 39.3°C for nanogel coated Fe@Au NPs. An opposite swelling –collapse behaviour is observed for the latter where the Fe@Au NPs act as bridge molecules pulling together the gelling units. Thereafter, Cyt C, a model protein drug and L-Dopa, a drug used in the clinical treatment of Parkinson’s disease were loaded separately into the nanogels and nanogel coated Fe@Au NPs, using a modified breathing-in mechanism. This gave high loading and encapsulation efficiencies (L Dopa: ~9% and 70µg/mg of nanogels, Cyt C: ~30% and 10µg/mg of nanogels respectively for both the drugs. The release kinetics of L-Dopa, monitored using UV-vis spectrophotometry was observed to be rather slow (over several hours) with highest release happening under a combination of high temperature (above VPTT) and acidic conditions. However, the release of L-Dopa from nanogel coated Fe@Au NPs was the fastest, accounting for release of almost 87% of the initially loaded drug in ~30 hours. The chemical structure of the drug, drug incorporation method, location of the drug and presence of Fe@Au NPs largely alter the drug release mechanism and the kinetics of these nanogels and Fe@Au NPs coated with nanogels.

Keywords: controlled release, nanogels, volume phase transition temperature, l-dopa

Procedia PDF Downloads 309

Authors: Evrim Colak, Andriy E. Serebryannikov, Pavel V. Usik, Ekmel Ozbay

Abstract:

Working with a dielectric photonic crystal (PC) structure which does not include surface corrugations, unidirectional transmission and dual-beam splitting are observed under normal incidence as a result of the strong diffractions caused by the embedded defect layer. The defect layer has twice the period of the regular PC segments which sandwich the defect layer. Although the PC has even number of rows, the structural symmetry is broken due to the asymmetric placement of the defect layer with respect to the symmetry axis of the regular PC. The simulations verify that efficient splitting and occurrence of strong diffractions are related to the dispersion properties of the Floquet-Bloch modes of the photonic crystal. Unidirectional and bi-directional splitting, which are associated with asymmetric transmission, arise due to the dominant contribution of the first positive and first negative diffraction orders. The effect of the depth of the defect layer is examined by placing single defect layer in varying rows, preserving the asymmetry of PC. Even for deeply buried defect layer, asymmetric transmission is still valid even if the zeroth order is not coupled. This transmission is due to evanescent waves which reach to the deeply embedded defect layer and couple to higher order modes. In an additional selected performance, whichever surface is illuminated, i.e., in both upper and lower surface illumination cases, incident beam is split into two beams of equal intensity at the output surface where the intensity of the out-going beams are equal for both illumination cases. That is, although the structure is asymmetric, symmetric bidirectional transmission with equal transmission values is demonstrated and the structure mimics the behavior of symmetric structures. Finally, simulation studies including the examination of a coupled-cavity defect for two different permittivity values (close to the permittivity values of GaAs or Si and alumina) reveal unidirectional splitting for a wider band of operation in comparison to the bandwidth obtained in the case of a single embedded defect layer. Since the dielectric materials that are utilized are low-loss and weakly dispersive in a wide frequency range including microwave and optical frequencies, the studied structures should be scalable to the mentioned ranges.

Keywords: asymmetric transmission, beam deflection, blazing, bi-directional splitting, defect layer, dual beam splitting, Floquet-Bloch modes, isofrequency contours, line defect, oblique incidence, photonic crystal, unidirectionality

Procedia PDF Downloads 167

Authors: Surekha Barkur, Aseefhali Bankapur, Santhosh Chidangil

Abstract:

Raman Tweezers technique has become prevalent in single cell studies. This technique combines Raman spectroscopy which gives information about molecular vibrations, with optical tweezers which use a tightly focused laser beam for trapping the single cells. Thus Raman Tweezers enabled researchers analyze single cells and explore different applications. The applications of Raman Tweezers include studying blood cells, monitoring blood-related disorders, silver nanoparticle-induced stress, etc. There is increased interest in the toxic effect of nanoparticles with an increase in the various applications of nanoparticles. The interaction of these nanoparticles with the cells may vary with their size. We have studied the effect of silver nanoparticles of sizes 10nm, 40nm, and 100nm on erythrocytes using Raman Tweezers technique. Our aim was to investigate the size dependence of the nanoparticle effect on RBCs. We used 785nm laser (Starbright Diode Laser, Torsana Laser Tech, Denmark) for both trapping and Raman spectroscopic studies. 100 x oil immersion objectives with high numerical aperture (NA 1.3) is used to focus the laser beam into a sample cell. The back-scattered light is collected using the same microscope objective and focused into the spectrometer (Horiba Jobin Vyon iHR320 with 1200grooves/mm grating blazed at 750nm). Liquid nitrogen cooled CCD (Symphony CCD-1024x256-OPEN-1LS) was used for signal detection. Blood was drawn from healthy volunteers in vacutainer tubes and centrifuged to separate the blood components. 1.5 ml of silver nanoparticles was washed twice with distilled water leaving 0.1 ml silver nanoparticles in the bottom of the vial. The concentration of silver nanoparticles is 0.02mg/ml so the 0.03mg of nanoparticles will be present in the 0.1 ml nanoparticles obtained. The 25 ul of RBCs were diluted in 2 ml of PBS solution and then treated with 50 ul (0.015mg) of nanoparticles and incubated in CO2 incubator. Raman spectroscopic measurements were done after 24 hours and 48 hours of incubation. All the spectra were recorded with 10mW laser power (785nm diode laser), 60s of accumulation time and 2 accumulations. Major changes were observed in the peaks 565 cm-1, 1211 cm-1, 1224 cm-1, 1371 cm-1, 1638 cm-1. A decrease in intensity of 565 cm-1, increase in 1211 cm-1 with a reduction in 1224 cm-1, increase in intensity of 1371 cm-1 also peak disappearing at 1635 cm-1 indicates deoxygenation of hemoglobin. Nanoparticles with higher size were showing maximum spectral changes. Lesser changes observed in case of 10nm nanoparticle-treated erythrocyte spectra.

Keywords: erythrocytes, nanoparticle-induced toxicity, Raman tweezers, silver nanoparticles

Procedia PDF Downloads 272

Authors: Muhandiram Rallage Ruvini Nisansala Yatigammana, Anuruddhika Kumudu Kumari Rajakaruna Jayathilaka

Abstract:

Sports injuries are common among teenagers and children engaged in organized sports. While most sports injuries are typical, some rare occurrences involve conditions such as eye, dental, cervical, and rare internal organ injuries, such as pancreatic injuries. These injuries, especially traumatic pancreatitis, require prompt attention due to their potential for severe and sometimes fatal complications. This case revolves around a real accident involving a 12-year-old girl, Piyumi, who suffered a face-to-face collision during netball practice, resulting in severe abdominal pain. After a medical examination, she was diagnosed with a rare pancreatic injury, uncommon in children compared to adults. In Piyumi’s case, she had a grade 3 pancreatic injury and underwent non-surgical management, successfully healing her wound without surgery. The study attempts to fill empirical and population gaps, addressing a rarely discussed injury experienced by a 12-year-old female netball player. The paper will also provide an in-depth understanding of pancreatic injury, which is a rare sports injury. The study’s main objective was to investigate the incidence and characteristics of pancreatic injury, particularly focusing on pancreatic trauma, among children and adolescents engaged in high-impact sports, such as netball. This research adopted a case study strategy, employing interviews as the primary data collection method. Interviews were conducted with Piyumi, her parents, and the two specialist doctors directly involved in her treatment, providing firsthand accounts and insights. By examining the case, the paper arrives at three main conclusions. Firstly, pancreatic damage is uncommon, especially in the sports world, and proper diagnosis is essential to avoiding health concerns, particularly for minors. Secondly, CT (Computed Tomography) was useful in locating the injury, as injuries can be diagnosed very well with Computed Tomography (CT) images. Finally, and most importantly, pancreatic injuries are infrequent, but trauma can still occur, particularly in high-impact sports or accidents involving extreme force or falls. These injuries should be accurately diagnosed and treated promptly.

Keywords: child athlete, pancreatic injury, rare sports injuries, sportswoman

Procedia PDF Downloads 51

Authors: Michal Biały, Konrad Pietrykowski, Rafal Sochaczewski

Abstract:

The kinematics and dynamics analysis of crank-piston system of aircraft engine. The object of the study was the high power aircraft engine ASz 62-IR. This engine is produced by a Polish company WSK "PZL-KALISZ" S.A.". All analyzes were performed numerically using CAD and CAE environment. Three-dimensional model of the crank-piston system was developed based on real engine located in the Laboratory of Centre of Innovation and Advanced Technologies of Lublin University of Technology. During the development of the model, the technique of reverse engineering - 3D scanning was used. ASz 62-IR engine is characterized by a radial type of crank-piston system. In this system the cylinders are arranged radially around the circle. This crank-piston system consists of a main connecting rod and eight additional connecting rods. In addition, three-dimensional model consists of a piston pins, pistons and piston rings. As a result of the specific engine design, characteristics of the piston individual movement are slightly different from each other. But the model assumes that they are the same during the analysis. Three-dimensional model of the engine was implemented into the MSC Adams software. The environment of MSC Adams allows for multibody simulation of the dynamic phenomena. This determines the state parameters of the moving elements, among which the load or force distribution on each kinematic node can be distinguished. Materials and characteristic materials parameters were adopted on the basis of commonly used materials for engine parts. The mass values of individual elements were adopted on the basis of real engine parts. The piston gas forces were replaced by calculation of pressure variations recorded during engine tests on the engine test bench. The research the changes of forces acting in the individual kinematic pairs of crank-piston system. The model allows to determine the load on the crankshaft main bearings. This gives the possibility for the main supports forces analysis The model allows for testing and simulation of kinematics and dynamics of a radial aircraft engine. This is the first stage of the work, which aims to numerical simulation of vibration of multi-cylinder aircraft engine. This work has been financed by the Polish National Centre for Research and Development, INNOLOT, under Grant Agreement No. INNOLOT/I/1/NCBR/2013.

Keywords: aircraft engine, CAD, CAE, dynamics, kinematics, MSC Adams, numerical simulation

Procedia PDF Downloads 358

Authors: Rui Huang, Thomas Richard, Masood Mostofi

Abstract:

The lifetime of impregnated diamond bits and their drilling efficiency are in part governed by the bit wear conditions, not only the extent of the diamonds’ wear but also their exposure or protrusion out of the matrix bonding. As much as individual diamonds wear, the bonding matrix does also wear through two-body abrasion (direct matrix-rock contact) and three-body erosion (cuttings trapped in the space between rock and matrix). Although there is some work dedicated to the study of diamond bit wear, there is still a lack of understanding on how matrix erosion and diamond exposure relate to the bit drilling response and drilling efficiency, as well as no literature on the process that governs bit sharpening a procedure commonly implemented by drillers when the extent of diamond polishing yield extremely low rate of penetration. The aim of this research is (i) to derive a correlation between the wear state of the bit and the drilling performance but also (ii) to gain a better understanding of the process associated with tool sharpening. The research effort combines specific drilling experiments and precise mapping of the tool-cutting face (impregnated diamond bits and segments). Bit wear is produced by drilling through a rock sample at a fixed rate of penetration for a given period of time. Before and after each wear test, the bit drilling response and thus efficiency is mapped out using a tailored design experimental protocol. After each drilling test, the bit or segment cutting face is scanned with an optical microscope. The test results show that, under the fixed rate of penetration, diamond exposure increases with drilling distance but at a decreasing rate, up to a threshold exposure that corresponds to the optimum drilling condition for this feed rate. The data further shows that the threshold exposure scale with the rate of penetration up to a point where exposure reaches a maximum beyond which no more matrix can be eroded under normal drilling conditions. The second phase of this research focuses on the wear process referred as bit sharpening. Drillers rely on different approaches (increase feed rate or decrease flow rate) with the aim of tearing worn diamonds away from the bit matrix, wearing out some of the matrix, and thus exposing fresh sharp diamonds and recovering a higher rate of penetration. Although a common procedure, there is no rigorous methodology to sharpen the bit and avoid excessive wear or bit damage. This paper aims to gain some insight into the mechanisms that accompany bit sharpening by carefully tracking diamond fracturing, matrix wear, and erosion and how they relate to drilling parameters recorded while sharpening the tool. The results show that there exist optimal conditions (operating parameters and duration of the procedure) for sharpening that minimize overall bit wear and that the extent of bit sharpening can be monitored in real-time.

Keywords: bit sharpening, diamond exposure, drilling response, impregnated diamond bit, matrix erosion, wear rate

Procedia PDF Downloads 78

Authors: Awadh O. Al-Anazi

Abstract:

As part of the organizational needs toward successful maintaining activities, a proper management system need to be put in place, ensuring the effectiveness of maintenance activities. The management system shall clearly describes the process of identifying, prioritizing, planning, scheduling, execution, and providing valuable feedback for all maintenance activities. Completion and accuracy of the system with proper implementation shall provide the organization with a strong platform for effective maintenance activities that are resulted in efficient outcomes toward business success. The purpose of this research was to introduce a practical tool for measuring the maintenance efficiency level within Saudi organizations. A comprehensive study was launched across many maintenance professionals throughout Saudi leading organizations. The study covered five main categories: work process, identification, planning and scheduling, execution, and performance monitoring. Each category was evaluated across many dimensions to determine its current effectiveness through a five-level scale from 'process is not there' to 'mature implementation'. Wide participation was received, responses were analyzed, and the study was concluded by highlighting major gaps and improvement opportunities within Saudi organizations. One effective implementation of the efficiency enhancement efforts was deployed in Saudi Kayan (one of Sabic affiliates). Below details describes the project outcomes: SK overall maintenance wrench time was measured at 20% (on average) from the total daily working time. The assessment indicates the appearance of several organizational gaps, such as a high amount of reactive work, poor coordination and teamwork, Unclear roles and responsibilities, as well as underutilization of resources. Multidiscipline team was assigned to design and implement an appropriate work process that is capable to govern the execution process, improve the maintenance workforce efficiency, and maximize wrench time (targeting > 50%). The enhanced work process was introduced through brainstorming and wide benchmarking, incorporated with a proper change management plan and leadership sponsorship. The project was completed in 2018. Achieved Results: SK WT was improved to 50%, which resulted in 1) reducing the Average Notification completion time. 2) reducing maintenance expenses on OT and manpower support (3.6 MSAR Actual Saving from Budget within 6 months).

Keywords: efficiency, enhancement, maintenance, work force, wrench time

Procedia PDF Downloads 121

Authors: Patrick Duffley

Abstract:

Hanks (2021) identifies three Frege-inspired commitments concerning propositions that are widely shared across the philosophy of language: (1) propositions are the primary, inherent bearers of representational properties and truth-conditions; (2) propositions are neutral representations possessing a ‘content’ that is devoid of ‘force; (3) propositions can be entertained or expressed without being asserted. Hanks then argues that the postulate of neutral content must be abandoned, and the primary bearers of truth-evaluable representation must be identified as the token acts of assertoric predication that people perform when they are thinking or speaking about the world. Propositions are ‘types of acts of predication, which derive their representational features from their tokens.’ Their role is that of ‘classificatory devices that we use for the purposes of identifying and individuating mental states and speech acts,’ so that ‘to say that Russell believes that Mont Blanc is over 4000 meters high is to classify Russell’s mental state under a certain type, and thereby distinguish that mental state from others that Russell might possess.’ It is argued in this paper that there is no need to classify an utterance of 'Russell believes that Mont Blanc is over 4000 meters high' as a token of some higher-order utterance-type in order to identify what Russell believes; the meanings of the words themselves and the syntactico-semantic relations between them are sufficient. In our view what Hanks has accomplished in effect is to build a convincing argument for dispensing with propositions completely in the philosophy of language. By divesting propositions of the role of being the primary bearers of representational properties and truth-conditions and fittingly transferring this role to the token acts of predication that people perform when they are thinking or speaking about the world, he has situated truth in its proper place and obviated any need for abstractions like propositions to explain how language can express things that are true. This leaves propositions with the extremely modest role of classifying mental states and speech acts for the purposes of identifying and individuating them. It is demonstrated here however that there is no need whatsoever to posit such abstract entities to explain how people identify and individuate such states/acts. We therefore make the modest proposal that the term ‘proposition’ be stricken from the vocabulary of philosophers of language.

Keywords: propositions, truth-conditions, predication, Frege, truth-bearers

Procedia PDF Downloads 39

Authors: Cui Li, Xu Yuping

Abstract:

Based on the question of, "Are short video creators who are digital workers controlled by platform rules?" this study discusses the specific ways of platform rules control and the impact on short video creators. Based on the theory of digital labor, this paper adopts the method of in-depth interview and participant observation and chooses 24 producers of short video content of Tiktok to conduct in-depth interview. At the same time, through entering the short video creation field, the author carries on the four-month field investigation, obtains the creation process related data, and analyzes how the short video creator, as the digital labor, is controlled by the platform rule, as well as the creator in this process of compromise and resistance, a more comprehensive presentation of the short video creators of the labor process. It is found that the short video creators are controlled by the platform rules, mainly in the control of traffic rules, and the creators create content, compromise and resist under the guidance of traffic. First, while the platform seems to offer a flexible and autonomous way for creators to monetize, the threshold for participating in the event is actually very high for creators, and the rules for monetizing the event are vague. Under the influence of the flow rule, the creator is faced unstable incomes and high costs. Therefore, creators have to follow the rules of traffic to guide their own creation, began to flow-oriented content production, mainly reflected in the need to keep up-to-date, the pursuit of traffic to ride on the hot spots, in order to flow regardless, set up people "Born for the show", by the label solidified content creation. Secondly, the irregular working hours lead to the extension and overwork of the working hours, which leads to the internal friction of the short video creators at the spiritual level, and finally leads to the Rat Race of video creation. Thirdly, the video creator has completed the internalization and compromise of the platform rules in practice, which promotes the creator to continue to create independently, and forms the intrinsic motive force of the creator. Finally, the rule-controlled short video creators resist and fight in flexible ways, make use of the mechanism and rules of the platform to carry on the second creation, carry on the routine production, purchase the false flow, transfer the creation position to maintain own creation autonomy.

Keywords: short videos, tiktok, production, digital labors

Procedia PDF Downloads 43

Authors: Amaia Martinez Martinez, Martin Turek, Carlos Ventura, Jay Drew

Abstract:

This study aims to assess the seismic performance of arch and dome structural systems made from easy to assemble precast blocks of recycled concrete. These systems have been developed by Lock Block Ltd. Company from Vancouver, Canada, as an extension of their currently used retaining wall system. The characterization of the seismic behavior of these structures is performed by a combination of experimental static and dynamic testing, and analytical modeling. For the experimental testing, several tilt tests, as well as a program of shake table testing were undertaken using small scale arch models. A suite of earthquakes with different characteristics from important past events are chosen and scaled properly for the dynamic testing. Shake table testing applying the ground motions in just one direction (in the weak direction of the arch) and in the three directions were conducted and compared. The models were tested with increasing intensity until collapse occurred; which determines the failure level for each earthquake. Since the failure intensity varied with type of earthquake, a sensitivity analysis of the different parameters was performed, being impulses the dominant factor. For all cases, the arches exhibited the typical four-hinge failure mechanism, which was also shown in the analytical model. Experimental testing was also performed reinforcing the arches using a steel band over the structures anchored at both ends of the arch. The models were tested with different pretension levels. The bands were instrumented with strain gauges to measure the force produced by the shaking. These forces were used to develop engineering guidelines for the design of the reinforcement needed for these systems. In addition, an analytical discrete element model was created using 3DEC software. The blocks were designed as rigid blocks, assigning all the properties to the joints including also the contribution of the interlocking shear key between blocks. The model is calibrated to the experimental static tests and validated with the obtained results from the dynamic tests. Then the model can be used to scale up the results to the full scale structure and expanding it to different configurations and boundary conditions.

Keywords: arch, discrete element model, seismic assessment, shake-table testing

Procedia PDF Downloads 191

Authors: Murray L. Ireland, Kevin J. Worrall, Rebecca Mackenzie, Thaleia Flessa, Euan McGookin, Douglas Thomson

Abstract:

Robotic rovers which are designed to work in extra-terrestrial environments present a unique challenge in terms of the reliability and availability of systems throughout the mission. Should some fault occur, with the nearest human potentially millions of kilometres away, detection and identification of the fault must be performed solely by the robot and its subsystems. Faults in the system sensors are relatively straightforward to detect, through the residuals produced by comparison of the system output with that of a simple model. However, faults in the input, that is, the actuators of the system, are harder to detect. A step change in the input signal, caused potentially by the loss of an actuator, can propagate through the system, resulting in complex residuals in multiple outputs. These residuals can be difficult to isolate or distinguish from residuals caused by environmental disturbances. While a more complex fault detection method or additional sensors could be used to solve these issues, an alternative is presented here. Using inverse simulation (InvSim), the inputs and outputs of the mathematical model of the rover system are reversed. Thus, for a desired trajectory, the corresponding actuator inputs are obtained. A step fault near the input then manifests itself as a step change in the residual between the system inputs and the input trajectory obtained through inverse simulation. This approach avoids the need for additional hardware on a mass- and power-critical system such as the rover. The InvSim fault detection method is applied to a simple four-wheeled rover in simulation. Additive system faults and an external disturbance force and are applied to the vehicle in turn, such that the dynamic response and sensor output of the rover are impacted. Basic model-based fault detection is then employed to provide output residuals which may be analysed to provide information on the fault/disturbance. InvSim-based fault detection is then employed, similarly providing input residuals which provide further information on the fault/disturbance. The input residuals are shown to provide clearer information on the location and magnitude of an input fault than the output residuals. Additionally, they can allow faults to be more clearly discriminated from environmental disturbances.

Keywords: fault detection, ground robot, inverse simulation, rover

Procedia PDF Downloads 282

Authors: Maria Stepankova, Lucie Vistejnova, Pavel Klein, Tereza Blassova, Marketa Slajerova, Radek Sedlacek, Martin Bartos, Jaroslav Chlupac

Abstract:

Background: Clinical outcome benefits of the segment rib fracture surgical therapy are well known and follow from better stabilization of the chest wall. Despite this, some authors still incline to conservative therapy and point out to possible rib fracture healing failure in connection with the bone vascular supply disturbance caused by metal plate implantation. This suggestion met neither experimental nor clinical verification and remains the object of discussion. In our pilot study we investigated the titanium plate fixation effect on the rib fracture healing in porcine model and its histological, biomechanical and radiological aspects. Materials and Method: Two porcine models (experimental group) underwent the operative chest wall stabilization with a titanium plate implantation after osteotomy. Two other porcine models (control group) were treated conservatively after osteotomy. Three weeks after surgery, all animals were sacrificed, treated ribs were explanted and the histological analysis, µCT imaging and biomechanical testing of the calluses tissue were performed. Results: In µCT imaging, experimental group showed a higher cortical bone volume compared to the control group. Histological analysis using the non-decalcified bone tissue blocks demonstrated more maturated callus with higher newly-formed osseous tissue ratio in experimental group in comparison to controls. In contrast, no significant differences in bone blood vessels supply in both groups were observed. This finding suggests that the bone blood supply in experimental group was not impaired. Biomechanical analysis using 3-point bending test demonstrated significantly higher bending stiffness and the maximum force in experimental group. Conclusion: Based on our observation, it could be concluded, that the titanium plate fixation of the rib fractures leads to faster bone callus maturation whereas does not cause the vascular supply impairment after 3 weeks and thus has a beneficial effect on the rib fracture healing.

Keywords: bone vascular supply, chest wall stabilization, fracture healing, histological analysis, titanium plate implantation

Procedia PDF Downloads 115

Authors: Zdzisław Kobos, Robert Jędrys, Zbigniew Wochyński

Abstract:

Motor activity and good health are sine qua non determinants of a proper practice of the profession, especially aviation. Therefore, candidates to the aviation are selected according their psychomotor ability by both specialist medical commissions. Moreover, they must past an examination of the physical fitness. During the studies in the air force academy, eye-hand coordination is formed in two stages. The future aircraft pilots besides all-purpose physical education must practice specialist training on SAGI. Training includes: looping, aerowheel, and gyroscope. Aim of the training on the above listed apparatuses is to form eye-hand coordination during the tasks in the air. Such coordination is necessary to perform various figures in the real flight. Therefore, during the education of the future pilots, determinants of the effective ways of this important parameter of the human body functioning are sought for. Several studies of the sport psychology indicate an important role of the temperament as a factor determining human behavior during the task performance and acquiring operating skills> Polish psychologist Jan Strelau refers to the basic, relatively constant personality features which manifest themselves in the formal characteristics of the human behavior. Temperament, being initially determined by the inborn physiological mechanisms, changes in the course of maturation and some environmental factors and concentrates on the energetic level and reaction characteristics in time. Objectives. This study aimed at seeking a relationship between temperamental features and eye-hand coordination formation during training on SAGI. Material and Methods: Group of 30 students of pilotage was examined in two situations. The first assessment of the eye-hand coordination level was carried out before the beginning of a 30-hour training on SAGI. The second assessment was carried out after training completion. Training lasted for 2 hours once a week. Temperament was evaluated with The Formal Characteristics of Behavior − Temperament Inventory (FCB-TI) developed by Bogdan Zawadzki and Jan Strelau. Eye-hand coordination was assessed with a computer version of the Warsaw System of Psychological Tests. Results: It was found that the training on SAGI increased the level of eye-hand coordination in the examined students. Conclusions: Higher level of the eye-hand coordination was obtained after completion of the training. Moreover, a relationship between eye-hand coordination level and selected temperamental features was statistically significant.

Keywords: temperament, eye-hand coordination, pilot, SAGI

Procedia PDF Downloads 423

Authors: Boce Zhang

Abstract:

Strategic innovation of nanotechnology to promote food safety has drawn tremendous attentions among research groups, which includes the need for research support during the implementation of the Food Safety Modernization Act (FSMA) in the United States. There are urgent demands and knowledge gaps to the understanding of a) food-water-bacteria interface as for how pathogens persist and transmit during food processing and storage; b) minimum processing requirement needed to prevent pathogen cross-contamination in the food system. These knowledge gaps are of critical importance to the food industry. However, the lack of knowledge is largely hindered by the limitations of research tools. Our groups recently endeavored two novel engineering systems with biomimetics and microfluidics as a holistic approach to hazard analysis and risk mitigation, which provided unprecedented research opportunities to study pathogen behavior, in particular, contamination, and cross-contamination, at the critical food-water-pathogen interface. First, biomimetically-patterned surfaces (BPS) were developed to replicate the identical surface topography and chemistry of a natural food surface. We demonstrated that BPS is a superior research tool that empowers the study of a) how pathogens persist through sanitizer treatment, b) how to apply fluidic shear-force and surface tension to increase the vulnerability of the bacterial cells, by detaching them from a protected area, etc. Secondly, microfluidic devices were designed and fabricated to study the bactericidal kinetics in the sub-second time frame (0.1~1 second). The sub-second kinetics is critical because the cross-contamination process, which includes detachment, migration, and reattachment, can occur in a very short timeframe. With this microfluidic device, we were able to simulate and study these sub-second cross-contamination scenarios, and to further investigate the minimum sanitizer concentration needed to sufficiently prevent pathogen cross-contamination during the food processing. We anticipate that the findings from these studies will provide critical insight on bacterial behavior at the food-water-cell interface, and the kinetics of bacterial inactivation from a broad range of sanitizers and processing conditions, thus facilitating the development and implementation of science-based food safety regulations and practices to mitigate the food safety risks.

Keywords: biomimetic materials, microbial food safety, microfluidic device, nanotechnology

Procedia PDF Downloads 343

Authors: Carla Lopes

Abstract:

It is clear nowadays that the proper performance of different speech acts is one of the most difficult obstacles that a foreign language learner has to overcome to be considered communicatively competent. This communication presents the results of an investigation on the pragmatic performance of Portuguese Language students at the University of Macau. The research discussed herein is based on a survey consisting of fourteen speaking situations to which the participants must respond in writing, and that includes different types of speech acts: apology, response to a compliment, refusal, complaint, disagreement and the understanding of the illocutionary force of indirect speech acts. The responses were classified in a five levels Likert scale (quantified from 1 to 5) according to their suitability for the particular situation. In general terms, we can summarize that about 45% of the respondents' answers were pragmatically competent, 10 % were acceptable and 45 % showed weaknesses at socio-pragmatic competence level. Given that the linguistic deviations were not taken into account, we can conclude that the faults are of cultural origin. It is natural that in the presence of orthogonal cultures, such as Chinese and Portuguese, there are failures of this type, barely solved in the four years of the undergraduate program. The target population, native speakers of Cantonese or Mandarin, make their first contact with the English language before joining the Bachelor of Portuguese Language. An analysis of the socio - pragmatic failures in the respondents’ answers suggests the conclusion that many of them are due to the lack of cultural knowledge. They try to compensate for this either using their native culture or resorting to a Western culture that they consider close to the Portuguese, that is the English or US culture, previously studied, and also widely present in the media and on the internet. This phenomenon, known as 'pragmatic transfer', can result in a linguistic behavior that may be considered inauthentic or pragmatically awkward. The resulting speech act is grammatically correct but is not pragmatically feasible, since it is not suitable to the culture of the target language, either because it does not exist or because the conditions of its use are in fact different. Analysis of the responses also supports the conclusion that these students present large deviations from the expected and stereotyped behavior of Chinese students. We can speculate while this linguistic behavior is the consequence of the Macao globalization that culturally casts the students, makes them more open, and distinguishes them from the typical Chinese students.

Keywords: Portuguese foreign language, pragmatic failures, pragmatic transfer, pragmatic competence

Procedia PDF Downloads 193

Authors: Béla Kovács, Éva Bódi, Farzaneh Garousi, Szilvia Várallyay, Áron Soós, Xénia Vágó, Dávid Andrási

Abstract:

In agriculture for analysis of elements in different food and food raw materials, moreover environmental samples generally flame atomic absorption spectrometers (FAAS), graphite furnace atomic absorption spectrometers (GF-AAS), inductively coupled plasma optical emission spectrometers (ICP-OES) and inductively coupled plasma mass spectrometers (ICP-MS) are routinely applied. An inductively coupled plasma mass spectrometer (ICP-MS) is capable for analysis of 70-80 elements in multielemental mode, from 1-5 cm3 volume of a sample, moreover the detection limits of elements are in µg/kg-ng/kg (ppb-ppt) concentration range. All the analytical instruments have different physical and chemical interfering effects analysing the above types of samples. The smaller the concentration of an analyte and the larger the concentration of the matrix the larger the interfering effects. Nowadays there is very important to analyse growingly smaller concentrations of elements. From the above analytical instruments generally the inductively coupled plasma mass spectrometer is capable of analysing the smallest concentration of elements. The applied ICP-MS instrument has Collision Cell Technology (CCT) also. Using CCT mode certain elements have better (smaller) detection limits with 1-3 magnitudes comparing to a normal ICP-MS analytical method. The CCT mode has better detection limits mainly for analysis of selenium, arsenic, germanium, vanadium and chromium. To elaborate an analytical method for trace elements with an inductively coupled plasma mass spectrometer the most important interfering effects (problems) were evaluated: 1) Physical interferences; 2) Spectral interferences (elemental and molecular isobaric); 3) Effect of easily ionisable elements; 4) Memory interferences. Analysing food and food raw materials, moreover environmental samples an other (new) interfering effect emerged in ICP-MS, namely the effect of various matrixes having different evaporation and nebulization effectiveness, moreover having different quantity of carbon content of food and food raw materials, moreover environmental samples. In our research work the effect of different water-soluble compounds furthermore the effect of various quantity of carbon content (as sample matrix) were examined on changes of intensity of the applied elements. So finally we could find “opportunities” to decrease or eliminate the error of the analyses of applied elements (Cr, Co, Ni, Cu, Zn, Ge, As, Se, Mo, Cd, Sn, Sb, Te, Hg, Pb, Bi). To analyse these elements in the above samples, the most appropriate inductively coupled plasma mass spectrometer is a quadrupole instrument applying a collision cell technique (CCT). The extent of interfering effect of carbon content depends on the type of compounds. The carbon content significantly affects the measured concentration (intensities) of the above elements, which can be corrected using different internal standards.

Keywords: elements, environmental and food samples, ICP-MS, interference effects

Procedia PDF Downloads 481

Authors: Saad Mohamed Elsaid Onaizah

Abstract:

One of the reasons for the intensive use of pesticides is to protect agricultural crops and orchards from pests or agricultural worms. The period of time that pesticides stay inside the soil is estimated at about (2) to (12) weeks. Perhaps the most important reason that led to groundwater pollution is the easy leakage of these harmful pesticides from the soil into the aquifers. This research aims to find the best ways to use trated activated charcoal with gold nitrate solution; For the purpose of removing the deadly pesticides from the aqueous solution by adsorption phenomenon. The most used pesticides in Egypt were selected, such as Malathion, Methomyl Abamectin and, Thiamethoxam. Activated charcoal doped with gold ions was prepared by applying chemical and thermal treatments to activated charcoal using gold nitrate solution. Adsorption of studied pesticide onto activated carbon /Au was mainly by chemical adsorption forming complex with the gold metal immobilised on activated carbon surfaces. Also, gold atom was considered as a catalyst to cracking the pesticide molecule. Gold activated charcoal is a low cost material due to the use of very low concentrations of gold nitrate solution. its notice the great ability of activated charcoal in removing selected pesticides due to the presence of the positive charge of the gold ion, in addition to other active groups such as functional oxygen and lignin cellulose. The presence of pores of different sizes on the surface of activated charcoal is the driving force for the good adsorption efficiency for the removal of the pesticides under study The surface area of the prepared char as well as the active groups were determined using infrared spectroscopy and scanning electron microscopy. Some factors affecting the ability of activated charcoal were applied in order to reach the highest adsorption capacity of activated charcoal, such as the weight of the charcoal, the concentration of the pesticide solution, the time of the experiment, and the pH. Experiments showed that the maximum limit revealed by the batch adsorption study for the adsorption of selected insecticides was in contact time (80) minutes at pH (7.70). These promising results were confirmed, and by establishing the practical application of the developed system, the effect of various operating factors with equilibrium, kinetic and thermodynamic studies is evident, using the Langmuir application on the effectiveness of the absorbent material with absorption capacities higher than most other adsorbents.

Keywords: waste water, pesticides pollution, adsorption, activated carbon

Procedia PDF Downloads 57

Authors: Salma Akter, Md. Kamal Uddin

Abstract:

Ashrayan (shelter) Prakalpa – a fully subsidized ‘integrated poverty eradication program’ through the provisioning of shelter of Bangladesh Government (GoB) targeting the internally displaced and homeless. In spite of the inclusiveness (poverty alleviation, employment opportunity, Tenure ship and training) of the shelter policy, dwellers are not merely questioned by the issue of 'the quality of life' .This study demonstrates how top-down policies, ambiguous ownership status of land and dwelling environments lead to ‘everyday compromise’ by the grassroots in both subjective (satisfaction, comfort and safety) and objective (physical design elements and physical environmental elements) issues in three respective scale macro (neighborhood) meso (shelter /built environment) and micro(family). It shows that by becoming subject to Government’s resettlements policies and after becoming user of its shelter units (although locally known as ‘barracks’ rather shelter or housing), the once displaced settlers assume a curious form of spatial practice where both social and spatial often bear slippery meanings. Thus, Policy-based shelter force the dwellers frequently compromise with their provided built environments and spaces within the settlements both in overtly and covertly. Compromises are made during the production of space and forms, whereas interesting new spaces and space-making practices emerge. The settlements under study are Dakshin Chandani Mahal Ashrayan Prakalpa located at the Eastern fringe area of Khulna, Bangladesh. In terms of methodology, this research is primarily exploratory and assumes a qualitative approach. Key tools used to obtain information are policy analysis, literature review, key informant interview, focus group discussion and participant observation at the level of dwelling and settlements. Necessary drawings and photographs have been taken to promote the study objective. Findings revealed that various shortages, inadequacies and negligence of policymakers make a compromising character of displaced by the means of 'quality of life' both in objective and subjective ground. Thus the study ends up with a recommendation to the policymakers to take an initiative to ensure the quality of life of the dwellers.

Keywords: Ashrayan, compromise, displaced people, quality of life

Procedia PDF Downloads 315