Search results for: hole enlargement phenomenon

Authors: Ghada Esheba, Bayan Hafiz, Ashwaq Al-Qarni, Abdulelah AlMalki, Esraa Kaheel

Abstract:

Hydatid disease is caused by genus Echinococcus, it is transmitted to human through sheep and cattle. People who lived in an endemic area should be suspected to have the disease. Pulmonary hydatid disease can be presented by respiratory manifestations as in our case. We report a case of child, 13 years old, who was presented by shortness of breath and non-productive cough 2 months ago. The patient had an attack of hemoptysis 3 months ago but there is no history of fever, other constitutional symptoms or any medical illness. The patient has had a close contact with a horse. On examination, the patient was oriented and vitally stable. Both side of chest were moving equally with decrease air entry on the left side of the chest. Cervical lymph node enlargement was also detected. The case was provisionally diagnosed as tuberculosis. The x-ray was normal, while CT scan showed two cysts in the left side. The patient was treated surgically with resection of both cysts without lobectomy. Broncho-alveolar lavage was done and together with plural effusion and both cysts were sent for histopathology. The patient received the following medication: albendazole 200MG/BID/Orally for 30 days and Cefuroxime 250MG/Q12H/Orally for 10 days.

Keywords: Echinococcus granulosus, hydatid disease, pediatrics, pulmonary hydatid cyst

Procedia PDF Downloads 249

Authors: Mahdi Pirmoradian, Olayinka Adigun, Christos Politis

Abstract:

Cooperative spectrum sensing is a crucial challenge in cognitive radio networks. Cooperative sensing can increase the reliability of spectrum hole detection, optimize sensing time and reduce delay in cooperative networks. In this paper, an efficient central capacity optimization algorithm is proposed to minimize cooperative sensing time in a homogenous sensor network using OR decision rule subject to the detection and false alarm probabilities constraints. The evaluation results reveal significant improvement in the sensing time and normalized capacity of the cognitive sensors.

Keywords: cooperative networks, normalized capacity, sensing time

Procedia PDF Downloads 604

Authors: Milena Trojanowska

Abstract:

Disability is a phenomenon for which meanings and definitions have evolved over the decades. This became the trigger to start a project to answer the question of what disability constitutes in the course of an incurable chronic disease. The chosen research group are people living with multiple sclerosis.The contextual phase of the research was participant observation at the Polish Multiple Sclerosis Society, the largest NGO in Poland supporting people living with MS and their relatives. The research techniques used in the project are (in order of implementation): group interviews with people living with MS and their relatives, narrative interviews, asynchronous technique, participant observation during events organised for people living with MS and their relatives.The researcher is currently conducting follow-up interviews, as inaccuracies in the respondents' narratives were identified during the data analysis. Interviews and supplementary research techniques were used over the four years of the research, and the researcher also benefited from experience gained from 12 years of working with NGOs (diaries, notes). The research was carried out in Poland with the participation of people living in this country only.The research has been based on grounded theory methodology in a constructivist perspectivedeveloped by Kathy Charmaz. The goal was to follow the idea that research must be reliable, original, and useful. The aim was to construct an interpretive theory that assumes temporality and the processualityof social life. TheAtlas.ti software was used to collect research material and analyse it. It is a program from the CAQDAS(Computer-Assisted Qualitative Data Analysis Software) group.Several key factors influencing the construction of a disability identity by people living with multiple sclerosis was identified:-course of interaction with significant relatives,- the expectation of identification with disability (expressed by close relatives),- economic profitability (pension, allowances),- institutional advantages (e.g. parking card),- independence and autonomy (not equated with physical condition, but access to adapted infrastructure and resources to support daily functioning),- the way a person with MS construes the meaning of disability,- physical and mental state,- medical diagnosis of illness.In addition, it has been shown that making an assumption about the experience of disability in the course of MS is a form of cognitive reductionism leading to further phenomenon such as: the expectation of the person with MS to construct a social identity as a person with a disability (e.g. giving up work), the occurrence of institutional inequalities. It can also be a determinant of the choice of a life strategy that limits social and individual functioning, even if this necessity is not influenced by the person's physical or psychological condition.The results of the research are important for the development of knowledge about the phenomenon of disability. It indicates the contextuality and complexity of the disability phenomenon, which in the light of the research is a set of different phenomenon of heterogeneous nature and multifaceted causality. This knowledge can also be useful for institutions and organisations in the non-governmental sector supporting people with disabilities and people living with multiple sclerosis.

Keywords: disability, multiple sclerosis, grounded theory, poland

Procedia PDF Downloads 78

Authors: Samuel Ahamefula

Abstract:

Turbulent motion is a highly nonlinear and complex phenomenon, and its modelling is still very challenging. In this study, we developed a hybrid computational approach to accurately simulate fluid turbulence phenomenon. The focus is coupling and transitioning between Direct Numerical Simulation (DNS) and Large Eddy Simulating Wall Models (LES-WM) regions. In the framework, high-order fidelity fluid dynamical methods are utilized to simulate the unsteady compressible Navier-Stokes equations in the Eulerian format on the unstructured moving grids. The coupling and transitioning of DNS and LES-WM are conducted through the linearly staggered Dirichlet-Neumann coupling scheme. The high-fidelity framework is verified and validated based on namely, DNS ability for capture full range of turbulent scales, giving accurate results and LES-WM efficiency in simulating near-wall turbulent boundary layer by using wall models.

Keywords: computational methods, turbulence modelling, turbulence entropy, navier-stokes equations

Procedia PDF Downloads 69

Authors: Jing-Fung Lin, Jer-Jia Sheu

Abstract:

In this study, an approach has been developed for the noise reduction of a muffler. The transmission loss (TL) in the muffler is maximized by the use of a double-chamber muffler, and a baffle with a hole is inserted between chambers. Taguchi method is used to optimize the design for the acoustical performance of the muffler. The TL performance is evaluated by COMSOL software. The excellent parameter combination for the maximum TL is attained as high as 35.30 dB in a wide frequency range from 10 Hz to 1400 Hz. The influence sequence of four parameters on TL is determined by the range analysis. The effects of length and expansion ratio of the first chamber on TL performance for the excellent program were discussed. Comparisons of the TL results from different designs are made.

Keywords: acoustics, baffle, chamber, muffler, Taguchi method, transmission loss

Procedia PDF Downloads 91

Authors: Hamsasew Hankebo Lemago, Dóra Hessz, Zoltán Erdélyi, Imre Miklós Szilágyi

Abstract:

Metal oxide inverse opals are a unique class of photocatalysts with a hierarchical structure that mimics the natural opal gemstone. They are composed of a network of interconnected pores, which provides a large surface area and efficient pathways for the transport of light and reactants. Atomic layer deposition (ALD) is a versatile technique for the synthesis of high-precision metal oxide thin films, including inverse opals. ALD allows for precise control over the thickness, composition, and morphology of the synthesized films, making it an ideal technique for the fabrication of photocatalysts with tailored properties. In this study, we report the synthesis of TiO2, ZnO, and Al2O3 inverse opal photocatalysts using thermal or plasma-enhanced ALD. The synthesized photocatalysts were characterized using a variety of techniques, including scanning electron microscopy (SEM)-energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Raman spectroscopy, photoluminescence (PL), ellipsometry, and UV-visible spectroscopy. The results showed that the ALD-synthesized metal oxide inverse opals had a highly ordered structure and a tunable pore size. The PL spectroscopy results showed low recombination rates of photogenerated electron-hole pairs, while the ellipsometry and UV-visible spectroscopy results showed tunable optical properties and band gap energies. The photocatalytic activity of the samples was evaluated by the degradation of methylene blue under visible light irradiation. The results showed that the ALD-synthesized metal oxide inverse opals exhibited high photocatalytic activity, even under visible light irradiation. The composites photocatalysts showed even higher activity than the individual metal oxide inverse opals. The enhanced photocatalytic activity of the composites can be attributed to the synergistic effect between the different metal oxides. For example, Al2O3 can act as a charge carrier scavenger, which can reduce the recombination of photogenerated electron-hole pairs. The ALD-synthesized metal oxide inverse opals and their composites are promising photocatalysts for a variety of applications, such as wastewater treatment, air purification, and energy production. For example, they can be used to remove organic pollutants from wastewater, decompose harmful gases in the air, and produce hydrogen fuel from water.

Keywords: ALD, metal oxide inverse opals, composites, photocatalysis

Procedia PDF Downloads 55

Authors: Torsten Hermanns, Thoufik Al Khawli, Wolfgang Schulz

Abstract:

In laser cutting as well as in long pulsed laser drilling of metals, it can be demonstrated that the ablation shape (the shape of cut faces respectively the hole shape) that is formed approaches a so-called asymptotic shape such that it changes only slightly or not at all with further irradiation. These findings are already known from the ultrashort pulse (USP) ablation of dielectric and semiconducting materials. The explanation for the occurrence of an asymptotic shape in laser cutting and long pulse drilling of metals is identified, its underlying mechanism numerically implemented, tested and clearly confirmed by comparison with experimental data. In detail, there now is a model that allows the simulation of the temporal (pulse-resolved) evolution of the hole shape in laser drilling as well as the final (asymptotic) shape of the cut faces in laser cutting. This simulation especially requires much less in the way of resources, such that it can even run on common desktop PCs or laptops. Individual parameters can be adjusted using sliders – the simulation result appears in an adjacent window and changes in real time. This is made possible by an application-specific reduction of the underlying ablation model. Because this reduction dramatically decreases the complexity of calculation, it produces a result much more quickly. This means that the simulation can be carried out directly at the laser machine. Time-intensive experiments can be reduced and set-up processes can be completed much faster. The high speed of simulation also opens up a range of entirely different options, such as metamodeling. Suitable for complex applications with many parameters, metamodeling involves generating high-dimensional data sets with the parameters and several evaluation criteria for process and product quality. These sets can then be used to create individual process maps that show the dependency of individual parameter pairs. This advanced simulation makes it possible to find global and local extreme values through mathematical manipulation. Such simultaneous optimization of multiple parameters is scarcely possible by experimental means. This means that new methods in manufacturing such as self-optimization can be executed much faster. However, the software’s potential does not stop there; time-intensive calculations exist in many areas of industry. In laser welding or laser additive manufacturing, for example, the simulation of thermal induced residual stresses still uses up considerable computing capacity or is even not possible. Transferring the principle of reduced models promises substantial savings there, too.

Keywords: asymptotic ablation shape, interactive process simulation, laser drilling, laser cutting, metamodeling, reduced modeling

Procedia PDF Downloads 194

Authors: Devam Sheth

Abstract:

Nuclear imaging with stress myocardial perfusion (stress test) is the preferred first line investigation for noninvasive evaluation of ischaemic heart condition. The sensitivity of this test is close to 90 % making it a very reliable test. However, rarely it gives a false negative result which can be explained by the phenomenon termed as “balanced ischaemia”. We present the case of a 78 year Caucasian female without any significant past cardiac history, who presents with chest pain and shortness of breath since one day. The initial ECG and cardiac enzymes were non-impressive. Few hours later, she had some substernal chest pain along with some ST segment depression in the lateral leads. Stress test comes back negative for any significant perfusion defects. However, given her typical symptoms, she underwent a cardiac catheterization which revealed significant triple vessel disease mandating her to get a bypass surgery. This unusual phenomenon of false nuclear stress test in the setting of positive ECG changes can be explained only by balanced ischemia wherein due to global myocardial ischemia, the stress test fails to reveal relative perfusion defects in the affected segments.

Keywords: balanced, false positive, ischemia, myocardial perfusion imaging

Procedia PDF Downloads 274

Authors: Mai Ashraf Talaat

Abstract:

Background: Vitamin C (ascorbic acid) is an essential nutrient for the development and repair of all body tissues. It can be obtained from a healthy diet or through supplementation. Due to its importance, vitamin C has become a mainstay in the treatment and prevention of many diseases and in maintaining immune, skin, bone and overall health. This review article aims to discuss the studies and case reports conducted to evaluate the effect of Vitamin C on oral health and the recent advances in oral medicine that involve the use of vitamin C. Data/Sources: The review was conducted for clinical studies, case reports and published literature in the English language that addresses this topic. An extensive search in the electronic databases of PubMed, PubMed Central, Web of Science, National Library of Medicine and ResearchGate was performed. Conclusion: Vitamin C is thought to treat periodontal diseases and gingival enlargement. It also affects biofilm formation and therefore, it helps in reducing caries incidence. Recently, vitamin C mesotherapy has been used to treat inflamed gingiva, bleeding gums and gingival hyperpigmentation. More research and randomized controlled trials are needed on this specific topic for more accurate judgment. Clinical significance: A minimally invasive approach - the usage of vitamin C in dental care could drastically reduce the need for surgical intervention.

Keywords: oral health, periodontology, vitamin C, Gingivitis

Procedia PDF Downloads 64

Authors: Yanuarti Retnaningrum, Cendrawasih A. Farmasyanti, Kuswahyuning

Abstract:

Orthodontists find challenges in treating patients who have cases of macroglossia and multiple tooth agenesis because difficulties in determining the causes, formulating a diagnosis and the potential for relapse after treatment. Definition of macroglossia is a tongue enlargement due to muscle hypertrophy, tumor or an endocrine disturbance. Macroglossia may cause many problems such as anterior proclination of upper and lower incisors, development of general diastema and anterior and/ or posterior open bite. Treatment for such patients with multiple tooth agenesis and macroglossia can be complex and must consider orthodontic and/or surgical interventions. This article discusses an orthodontic non surgical approach to a patient with a general diastema in both maxilla and mandible associated with multiple tooth agenesis and macroglossia. Fixed orthodontic therapy with straightwire appliance was used for space closure in anterior region of maxilla and mandible, also to create a space suitable for future prosthetic restoration. After 12 months treatment, stable and functional occlusal relationships was achieved, although still have edentulous area in both maxilla and mandible. At the end of the orthodontic treatment was obtained with correct overbite and overjet values. After removal of the brackets, a maxillary and mandibular removable retainer combine with artificial tooth were placed for retention.

Keywords: general diastema, macroglossia, space closure, tooth agenesis

Procedia PDF Downloads 157

Authors: Yudhajit Datta

Abstract:

Will is a phenomenon that has puzzled humanity for a long time. It is a belief that Will Power of an individual affects the success achieved by an individual in life. It is thought that a person endowed with great will power can overcome even the most crippling setbacks of life while a person with a weak will cannot make the most of life even the greatest assets. Behavioral aspects of the human experience such as will are rarely subjected to quantitative study owing to the numerous uncontrollable parameters involved. This work is an attempt to subject the phenomena of will to the test of an artificial neural network. The claim being tested is that will power of an individual largely determines success achieved in life. In the study, an attempt is made to incorporate the behavioral phenomenon of will into a computational model using data pertaining to the success of individuals obtained from an experiment. A neural network is to be trained using data based upon part of the model, and subsequently used to make predictions regarding will corresponding to data points of success. If the prediction is in agreement with the model values, the model is to be retained as a candidate. Ultimately, the best-fit model from among the many different candidates is to be selected, and used for studying the correlation between success and will.

Keywords: will power, will, success, apathy factor, random factor, characteristic function, life story

Procedia PDF Downloads 356

Authors: Tianchen Dai

Abstract:

Shantytowns are special historical products in china, possessing strong particularity and typicality, the theoretical value and the practical significance of which are deemed to hold great importance in the modern development of residential areas in China. The renovation planning of shantytowns can be very challenging in terms of cultural inheritance. The traditional lifestyle, one of the key elements building up residents’ perception of affiliation, should be carried forward in the renovation planning of shantytowns. Mobile vending can be considered as a rare business model survived within modern commercial environment, thanks to the unique spatial characteristics of Chinese shantytowns. This article mainly investigates the unique phenomenon of mobile vending in shantytowns, discussing the operating mechanism and rationality behind this commercial phenomenon. For humanistic concern, the innovative conservation of mobile vending, as a means to preserve the vivacious traditional lifestyle of local residents, can be realized through substantial urban design strategies, including spatial design of public space, height control of the facades, and traffic management around and inside shantytowns.

Keywords: cultural inheritance, mobile vending, renovation planning, shantytowns

Procedia PDF Downloads 449

Authors: Manouchehr Amiri

Abstract:

This article introduces a general notion of physical bit information that is compatible with the basics of quantum mechanics and incorporates the Shannon entropy as a special case. This notion of physical information leads to the Binary data matrix model (BDM), which predicts the basic results of quantum mechanics, general relativity, and black hole thermodynamics. The compatibility of the model with holographic, information conservation, and Landauer’s principles are investigated. After deriving the “Bit Information principle” as a consequence of BDM, the fundamental equations of Planck, De Broglie, Beckenstein, and mass-energy equivalence are derived.

Keywords: physical theory of information, binary data matrix model, Shannon information theory, bit information principle

Procedia PDF Downloads 133

Authors: Hamidreza Jahani, Zahra Salehzadeh, Ehsan Amini, Mohsen Tohidifar

Abstract:

Calvarial Hyperostosis Syndrome (CHS) is a benign bone disease of the skull. It is a non-neoplastic and proliferative bone disease, and the main feature of the disease is progressive and asymmetrical bone involvement. CHS is mostly reported in young male and female bullmastiff dogs and less frequently in other breeds. The etiology of CHS is unknown. This is the first case report of CHS in Iran. A 3-month-old male Persian Mastiff was presented with chief complaints of multiple episodes of seizure, pacing, bizarre behavior, delayed growth, head pressing, and difficulty in opening the mouth. Central blindness and open fontanelles were observed in clinical examination. No abnormality was found in the complete blood count and routine blood biochemical tests. CT scan findings include cortical thickening of frontal and parietal bones and enlargement of the left retropharyngeal lymph node. For treatment, oral clindamycin for two weeks, prednisolone and phenobarbital for one month, respectively, were administrated, and the case showed improvement after a week and recovered after one month.

Keywords: calvarial hyperostosis, Persian Mastiff, frontal bone, seizure

Procedia PDF Downloads 111

Authors: Amanda Aliende da Matta

Abstract:

This communication presents an aspect of phenomenon selection in an applied hermeneutic phenomenology study on care and vulnerability: the need to consider it as a situated universal. For that, we will first present the study and its methodology. Secondly, we will expose the need to understand phenomena as situation-defined, incorporating feminist thought. In an informatics class for 14 year olds, we explained the exercise: students have to make a 5 slide presentation about a topic of their choice. A does it on streetwear, B on Cristiano Ronaldo, C on Marvel, but J did it on Down Syndrome. Introducing it to the class, J explains the physical and cognitive differences caused by trisomy; when asked to explain it further, he says: "they are angels, teacher," and shows us a poster on his cellphone that says: if you laugh at a different child he will laugh with you because his innocence outweighs your ignorance. The anecdote shows, better than any theoretical explanation, something that some vulnerable people have; something beautiful and special but difficult to define. Let's call this something caring. The research has the main objective of accounting for the experience of caregiving in vulnerability, and it will be carried out with Applied Hermeneutic Phenomenology (AHP). The method's objective is to investigate the lived human experience in its pre-reflexive dimension to know its meaning structures. Contrary to other research methods, AHP does not produce theory about a specific context but seeks the meaning of the lived experience, in its characteristic of human experience. However, it is necessary that we understand care as defined in a concrete situation. We cannot start the research with an a priori definitive concept of care, or we would fall into the mistake of closing ourselves to only what we already know, as explained by Levinas. We incorporate, then, the notion of situated universals. Loyal to phenomenology, the definition of the phenomenon should start with an investigation of the word's etymology: the word cura, in its etymological root, means care. And care comes from the Latin word cogitātus/cōgĭto, which means "to pursue something in mind" and "to consider thoroughly." The verb cōgĭto, meanwhile, is composed of co- (altogether) and agitare (to deal with or think committedly about something, to concern oneself with) / ăgĭto (to set in motion, to move). Care, therefore, has in its origin a meditation on something, a concern about something, a verb that has a sense of action and movement. To care is to act out of concern for something/someone. This etymology, though, is not the final definition of the phenomenon, but only its skeleton. It needs to be embodied in the concrete situation to become a possible lived experience. And that means that the lived experience descriptions (LEDs) should be selected by taking into consideration how and if care was engendered in that concrete experience. Defining the phenomenon has to take into consideration situated knowledge.

Keywords: applied hermeneutic phenomenology, care ethics, hermeneutics, phenomenology, situated universalism

Procedia PDF Downloads 59

Authors: Gert Van Schalkwyk, Chris Cloete

Abstract:

South Africa is experiencing a massive housing backlog in urban low-cost housing. A backlog in the transfer of low-cost housing units is exacerbated by various impediments and delays that exist in the current legal framework. Structured interviews were conducted with forty-five practicing conveyancers and fifteen deeds office examiners at the Deeds Office in Pretoria, South Africa. One of the largest, the Deeds Office in Pretoria implements a uniform registration process and can be regarded as representative of other deeds offices in South Africa. It was established that a low percentage of low-cost properties are freely transferable. The main economic impediments are the absence of financing and the affordability or payment of rates and taxes to local government. Encroachment of buildings on neighboring stands caused by the enlargement of existing small units on small stands also causes long-term unresolved legal disputes. In addition, as the transfer of properties is dependent on the proper functioning of administrative functions of various government departments, the adverse service delivery of government departments hampers transfer. Addressing the identified problems will contribute to a more sustainable process for the transfer of low-cost housing units in South Africa.

Keywords: conveyancing, low-cost housing, South Africa, tenure, titling, transfer

Procedia PDF Downloads 103

Authors: Wakayama Shunya, Okubo Kazuya, Fujii Toru, Sakata Daisuke, Kado Noriyuki, Furutachi Hiroshi

Abstract:

The purpose of this study is to propose an effective method to improve frictional coefficient of modified shoe rubber soles with added glass fibers onto the icy and snowy road surfaces in order to prevent slip-and-fall accidents by the users. Added fibers in the rubber were uniformly tilted to the perpendicular direction of the frictional surface, where tilting angle was -60, -30, +30, +60, 90 degrees and 0 for usual specimen, respectively. It was found that horizontal arraignment was effective to improve the frictional coefficient when glass fibers were embedded in the shoe rubber, while the standing in normal direction of the embedded glass fibers on the shoe surface was also effective to do that once after they were exposed from the shoe rubber with its abrasion. These improvements were explained by the increase of stiffness against the shear deformation of the rubber at the critical frictional state and the enlargement of resistance force for extracting exposed fibers from the ice and snow, respectively. Current study suggested that effective arraignments in the tilting angle of the added fibers should be applied in designing rubber shoe soles to keep the safeties for uses in regions of cold climates.

Keywords: frictional coefficient, shoe soles, icy and snowy road, glass fibers, tilting angle

Procedia PDF Downloads 473

Authors: P. Kamphikul, P. Krachodnok, R. Wongsan

Abstract:

This paper presents the gain improvement of a sector antenna for mobile phone base station by using the new technique to enhance its gain for microstrip antenna (MSA) array without construction enlargement. The curved woodpile Electromagnetic Band Gap (EBG) has been utilized to improve the gain instead. The advantages of this proposed antenna are reducing the length of MSAs array but providing the higher gain and easy fabrication and installation. Moreover, it provides a fan-shaped radiation pattern, wide in the horizontal direction and relatively narrow in the vertical direction, which appropriate for mobile phone base station. The paper also presents the design procedures of a 1x8 MSAs array associated with U-shaped reflector for decreasing their back and side lobes. The fabricated curved woodpile EBG exhibits bandgap characteristics at 2.1 GHz and is utilized for realizing a resonant cavity of MSAs array. This idea has been verified by both the Computer Simulation Technology (CST) software and experimental results. As the results, the fabricated proposed antenna achieves a high gain of 20.3 dB and the half-power beam widths in the E- and H-plane of 36.8 and 8.7 degrees, respectively. Good qualitative agreement between measured and simulated results of the proposed antenna was obtained.

Keywords: gain improvement, microstrip antenna array, electromagnetic band gap, base station

Procedia PDF Downloads 282

Authors: Shun Horikoshi, Tohru Kawabe

Abstract:

This study presents performance analysis results of SMC (Sliding mode control) with changing the chattering functions applied to slip suppression problem of electric vehicles (EVs). In SMC, chattering phenomenon always occurs through high frequency switching of the control inputs. It is undesirable phenomenon and degrade the control performance, since it causes the oscillations of the control inputs. Several studies have been conducted on this problem by introducing some general saturation function. However, study about whether saturation function was really best and the performance analysis when using the other functions, weren’t being done so much. Therefore, in this paper, several candidate functions for SMC are selected and control performance of candidate functions is analyzed. In the analysis, evaluation function based on the trade-off between slip suppression performance and chattering reduction performance is proposed. The analyses are conducted in several numerical simulations of slip suppression problem of EVs. Then, we can see that there is no difference of employed candidate functions in chattering reduction performance. On the other hand, in slip suppression performance, the saturation function is excellent overall. So, we conclude the saturation function is most suitable for slip suppression sliding mode control.

Keywords: sliding mode control, chattering function, electric vehicle, slip suppression, performance analysis

Procedia PDF Downloads 297

Authors: N. David, H. O. Gao

Abstract:

Air pollution is a serious environmental threat on a global scale and can cause harm to human health, morbidity and premature mortality. Reliable monitoring and control systems are therefore necessary to develop coping skills against the hazards associated with this phenomenon. However, existing environmental monitoring means often do not provide a sufficient response due to practical and technical limitations. Commercial microwave links that form the infrastructure for transmitting data between cell phone towers can be harnessed to map rain at high tempo-spatial resolution. Rainfall causes a decrease in the signal strength received by these wireless communication links allowing it to be used as a built-in sensor network to map the phenomenon. In this study, we point to the potential that lies in this system to indirectly monitor areas where air pollution is reduced. The relationship between pollutant wash-off and rainfall provides an opportunity to acquire important spatial information about air quality using existing cell-phone tower signals. Since the density of microwave communication networks is high relative to any dedicated sensor arrays, it could be possible to rely on this available observation tool for studying precipitation scavenging on air pollutants, for model needs and more.

Keywords: air pollution, commercial microwave links, rainfall, washout

Procedia PDF Downloads 91

Authors: Phibankhamti Ryngnga

Abstract:

It is a common phenomenon worldwide that farmland has been gradually converted for urban development particularly in the 21st century keeping in mind the population increase on the other hand. Since food demand and supply are not in equilibrium in urban set up, therefore, there is a need for alternative to feed the hungry urban settlers worldwide. In this regard, urban rooftop farming is the only way out to meet the growing demand for food production with the extra benefits of making our urban areas and cities greener and when the populace is exposed to nature and vegetation, it in turn provides an array of psychological benefits, from decreased anxiety to increased productivity. Bare roofs in cities absorb and then radiate heat — a phenomenon known as the “heat island effect. This increases energy usage and contributes to the poor air quality that often plagues big cities. But Urban rooftop farming do provide many solutions to help cool buildings, ultimately reducing carbon emissions, and by growing food in the communities they serve, rooftop farmers lessen the environmental impact of food transportation. This paper will emphasise the significance of Urban roof farming in the present century which in itself a multi-solution to various city problems.

Keywords: urban, roof farming, smart solution, sustainability

Procedia PDF Downloads 109

Authors: Mauro Cristeche

Abstract:

This work begins with a very simple question: How does the State spend? Argentina is witnessing a process of growing nationalization of social life, so it is necessary to find out the explanations of the phenomenon on the specific dynamic of the capitalist mode of production in Argentina and its transformations in the last decades. Then the new question is: what happened in Argentina that could explain this phenomenon? Since the seventies, the capital growth in Argentina faces deep competitive problems. Until that moment the agrarian wealth had worked as a compensation mechanism, but it began to find its limits. In the meantime, some important demographical and structural changes had happened. The strategy of the capitalist class had to become to seek in the cheapness of the labor force the main source of compensation of its weakness. As a result, a tendency to worsen the living conditions and fragmentation of the working class started to develop, manifested by unemployment, underemployment, and the fall of the purchasing power of the salary as a highlighted fact. As a consequence, it is suggested that the role of the State became stronger and public expenditure increased, as a historical trend, because it has to intervene to face the contradictions and constant growth problems posed by the development of capitalism in Argentina. On the one hand, the State has to guarantee the process of buying the cheapened workforce and at the same time the process of reproduction of the working class. On the other hand, it has to help to reproduce the individual capitals but needs to ‘attack’ them in different ways. This is why the role of the State is said to be the general political representative to the national portion of the total social capital. What will be studied is the dynamic of the intervention of the Argentine State in the context of the particular national process of capital growth, and its dynamics in the last decades. What this paper wants to show are the main general causes that could explain the phenomenon of nationalization of the social life and how it has impacted the life conditions of the working class and the system of rights.

Keywords: Argentina, nationalization, public policies, rights, state

Procedia PDF Downloads 113

Authors: Rachid Mosbah, Aziez Chettoum, Zouhir Djerrou, Alberto Mantovani

Abstract:

Selective serotonin reuptake inhibitors (SSRI) are a class of molecules used in treating depression, anxiety, and mood disorders. Paroxetine (PRT) is one of the mostly prescribed antidepressant which has attracted great attention regarding its side effects in recent years. This study was planned to assess the adverse effects of PRT on the biochemical parameters and reproductive system. Fourteen male Wistar rats were randomly allocated into two groups (7 rats or each): control and treated with PRT at dose of 5mg/kg.bw for two weeks. At the end of the experiment, blood was collected from retro orbital plexus for measuring the biochemical parameters, whereas the reproductive organs were removed for measuring semen quality and the histological investigations. Results showed that PRT induced significant changes in some biochemical parameters and alteration of semen quality including sperm count, spermatids number and sperm viability, motility, and abnormalities. The histopathological examinations of testis and epididymis revealed an alteration of spermatogenesis, cellular disorganization and vacuolization, enlargement of interstitial space, shrinkage and degenerative changes in the epithelium of seminiferous and epididymal tubules with few to nil numbers of spermatozoa in their lumen. In conclusion, PRT treatment caused changes in some biochemical parameters and sperm profile as well as histopathologic effects of reproductive organs.

Keywords: antidepressant, biochemical parameters, reproductive function, paroxetine

Procedia PDF Downloads 100

Authors: Ming Lu, Xiaojun Li, Bodi Lu, Juehui Xing

Abstract:

Earthquake damage phenomenon of each large earthquake gives comprehensive and profound real test to the dynamic performance and failure mechanism of different engineering structures. Cognitive engineering structure characteristics through seismic damage phenomenon are often far superior to expensive shaking table experiments. After the earthquake, people will record a variety of different types of engineering damage photos. However, a large number of earthquake damage photographs lack sufficient information and reduce their using value. To improve the research value and the use efficiency of engineering seismic damage photographs, this paper objects to explore and show seismic damage background information, which includes the earthquake magnitude, earthquake intensity, and the damaged structure characteristics. From the research requirement in earthquake engineering field, the authors use the 2008 China Wenchuan M8.0 earthquake photographs, and provide four kinds of attribute indexes and classification, which are seismic information, structure types, earthquake damage parts and disaster causation factors. The final object is to set up an engineering structural seismic damage database based on these four attribute indicators and classification, and eventually build a website providing seismic damage photographs.

Keywords: attribute index, classification method, earthquake damage picture, engineering structure

Procedia PDF Downloads 739

Authors: Rizka Yunita, Mas Aji Rizki Wijayanto

Abstract:

Computational fluid dynamics (CFD) is the solution to explain how fluid dynamics behavior. In this work, we obtain the effect of channel width of two-dimensional fluid visualization. Using a horizontal water tunnel and flowing soap film, we got a visualization of continuous film that can be observe a graphical overview of the flow that occurs on a space or field in which the fluid flow. The horizontal water tunnel we used, divided into three parts, expansion area, parallel area that used to test the data, and contraction area. The width of channel is the boundary of parallel area with the originally width of 7.2 cm, and the variation of channel width we observed is about 1 cm and its times. To compute the velocity, vortex shedding, and other physical parameters of fluid, we used the cyclinder circular as an obstacle to create a von Karman vortex in fluid and analyzed that phenomenon by using Particle Imaging Velocimetry (PIV) method and comparing Reynolds number and Strouhal number from the visualization we got. More than width the channel, the film is more turbulent and have a separation zones that occurs of uncontinuous flowing fluid.

Keywords: flow visualization, width of channel, vortex, Reynolds number, Strouhal number

Procedia PDF Downloads 351

Authors: Hamid Goharnejad, Milad Sadeghpoor Moalem, Mahmood Zakeri Niri, Leili Sadeghi Khalegh Abadi

Abstract:

While there are many benefits to using reservoir dams, their break leads to destructive effects. From the viewpoint of International Committee of Large Dams (ICOLD), dam break means the collapse of whole or some parts of a dam; thereby the dam will be unable to hold water. Therefore, studying dam break phenomenon and prediction of its behavior and effects reduces losses and damages of the mentioned phenomenon. One of the most common types of reservoir dams is embankment dam. Overtopping in embankment dams occurs because of flood discharge system inability in release inflows to reservoir. One of the most important issues among managers and engineers to evaluate the performance of the reservoir dam rim when sliding into the storage, creating waves is large and long. In this study, the effects of floods which caused the overtopping of the dam have been investigated. It was assumed that spillway is unable to release the inflow. To determine outflow hydrograph resulting from dam break, numerical model using Flow-3D software and empirical equations was used. Results of numerical models and their comparison with empirical equations show that numerical model and empirical equations can be used to study the flood resulting from dam break.

Keywords: embankment dam break, empirical equations, Taleghan dam, Flow-3D numerical model

Procedia PDF Downloads 299

Authors: M. Ramesh, Manish K. Niranjan

Abstract:

The electronic, structural and thermoelectric properties of Mg₂SiSn (110) surface are investigated within the framework of first principle density functional theory and semi classical Boltzmann approach. In particular, directional dependent thermoelectric properties such as electrical conductivity, thermal conductivity, Seebeck coefficient and figure of merit are explored. The (110)-oriented Mg₂SiSn surface exhibits narrow indirect band gap of ~0.17 eV. The thermoelectric properties are found to be significant along the y-axis at 300 K and along x-axis at 500 K. The figure of merit (ZT) for hole carrier concentration is found to be significantly large having magnitude 0.83 (along x-axis) at 500 K and 0.26 (y-axis) at 300 K. Our results suggest that Mg₂SiSn (110) surface is promising for various thermoelectric applications due to its overall good thermoelectric properties.

Keywords: thermoelectric, surface science, semiconducting silicide, first principles calculations

Procedia PDF Downloads 205

Authors: Hamidreza Fazlollahi

Abstract:

The Re ́nyi entropy comprises a group of data estimates that sums up the well-known Shannon entropy, acquiring a considerable lot of its properties. It appears as unqualified and restrictive entropy, relative entropy, or common data, and has found numerous applications in information theory. In the Re ́nyi’s argument, the area law of the black hole entropy plays a significant role. However, the total entropy can be modified by some quantum effects, motivated by the randomness of a system. In this note, by employing this modified entropy relation, we have derived corrections to Friedmann equations. Taking this entropy associated with the apparent horizon of the Friedmann-Robertson-Walker Universe and assuming the first law of thermodynamics, dE=T_A (dS)_A+WdV, satisfies the apparent horizon, we have reconsidered expanding Universe. Also, the second thermodynamics law has been examined.

Keywords: Friedmann equations, dark energy, first law of thermodynamics, Reyni entropy

Procedia PDF Downloads 70

Authors: A. E. Agbogu

Abstract:

While scholars have predicted that identity politics (or what is euphemistically referred to as ethnic politics in Nigeria) were a dying phenomenon in other parts of the world, in Nigeria, it has remained the basis of political activity and has indeed become not only the unwritten law of all calculations in the political firmament of the country but also the ultimo ratio. We intend in the paper that follows to explore the reason for this unhealthy development. The paper seeks to offer explanations for the paradoxical reality of the upsurge of ethnic politics in Nigeria when in fact, the phenomenon is apparently on a downward spiral elsewhere in the world, particularly in countries that are at par with Nigeria in terms of national development. The paper is descriptive and qualitative and has relied on available data for its source of materials. Among other things, the paper locates identity politics as a tool in the hands of a national elite that has not transcended the limitations imposes by the shackles of the parsonian particularistic polar attributes which have tended to fixate their weltanschauung or world view on attachments that are unpardonably primordial. In the event, ethnicity becomes a veritable instrument not only for cheap sectional mobilization but also a means for seeking access to the so-called national cake. It is recommended that a way out of this socio-politico malady is the creation of a political arrangement that conduces to the gravitational tendency which will lead to the transfer of loyalties away from the extant ethno-nationalities to the centre.

Keywords: ethnicism, development, crisis, identity politics

Procedia PDF Downloads 258

Authors: Hassane Ben Slimane, Dennai Benmoussa, Abderrachid Helmaoui

Abstract:

We have theoretically calculated the photovoltaic conversion efficiency of a graded interface CdS/CIGS solar cell, which can be experimentally fabricated. Because the conduction band discontinuity or spike in an abrupt heterojunction CdS/CIGS solar cell can hinder the separation of hole-electron by electric field, a graded interface layer is uses to eliminate the spike and reduces recombination in space charge region. This paper describes the role of the graded band gap interface layer in decreasing the performance of the heterojunction cell. By optimizing the thickness of the graded region, an improvement of conversion efficiency has been observed in comparison to the conventional CIGS system.

Keywords: heterojunction, solar cell, graded interface, CIGS

Procedia PDF Downloads 376