Search results for: continued fraction expansion

Authors: Jeni A. Popescu, Ionut Porumbel, Valeriu A. Vilag, Cleopatra F. Cuciumita

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The paper presents a thermodynamic cycle analysis for three turboshaft engines. The first is the cycle is a Brayton cycle, describing the evolution of a classical turboshaft, based on the Klimov TV2 engine. The other two cycles aim at approaching an Ericsson cycle, by replacing the Brayton cycle adiabatic expansion in the turbine by quasi-isothermal expansion. The maximum quasi-Ericsson cycles temperature is set to a lower value than the maximum Brayton cycle temperature, equal to the Brayton cycle power turbine inlet temperature, in order to decrease the engine NOx emissions. Also, the power distribution over the stages of the gas generator turbine is maintained the same. In the first of the two considered quasi-Ericsson cycle, the efficiencies of the gas generator turbine stage. Also, the power distribution over the stages of the gas generator turbine is maintained the same. In the first of the two considered quasi-Ericsson cycle, the efficiencies of the gas generator turbine stages are maintained the same as for the reference case, while for the second, the efficiencies are increased in order to obtain the same shaft power as in the reference case. It is found that in the first case, both the shaft power and the thermodynamic efficiency of the engine decrease, while in the second, the power is maintained, and even a slight increase in efficiency can be noted.

Keywords: combustion, Ericsson, thermodynamic analysis, turbine

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Authors: Hanan Bin Nakhi, Asaad M. Albadrawi, Maged Al Shahat, ‎Entesar Mandani

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Background:‎ Kawasaki disease (KD) is one of the most common vasculitis of childhood. ‎It is considered the leading cause of acquired heart disease in children. The ‎peak age of occurrence is 6 to 24 months, with 80% of affected children being ‎less than 5 years old. There are only a few reports of KD in infants younger ‎than 6 months. Infants had a higher incidence of atypical KD and of coronary ‎artery complications. This case report from Kuwait will reinforce considering ‎atypical KD in case of sepsis like condition with negative cultures and ‎unresponding to systemic antibiotics. Early diagnosis allows early treatment ‎with intravenous immune globulin (IVIG) and so decreases the incidence of ‎cardiac aneurysm.‎ Case Report:‎ A 2 month old female infant, product of full term normal delivery to ‎consanguineous parents, presented with fever and poor feeding. She was ‎admitted and treated as urinary tract infection as her urine routine revealed ‎pyurea. The baby continued to have persistent fever and hypoactivity inspite ‎of using intravenous antibiotics. Latter, she developed non purulent ‎conjunctivitis, skin mottling, oedema of the face / lower limb and was treated ‎in intensive care unit as a case of septic shock. In spite of her partial general ‎improvement, she continued to look unwell, hypoactive and had persistent ‎fever. Septic work up, metabolic, and immunologic screen were negative. KD ‎was suspected when the baby developed polymorphic erythematous rash and ‎noticed to have peeling of skin at perianal area and periangular area of the ‎fingers of the hand and feet. IVIG was given in dose of 2 gm/kg/day in single ‎dose and aspirin 100 mg/kg/day in four divided doses. The girl showed marked ‎clinical improvement. The fever subsided dramatically and the level acute ‎phase reactant markedly decreased but the platelets count increased to ‎‎1600000/mm3. Echo cardiography showed mild dilatation of mid right ‎coronary artery. Aspirin was continued in a dose of 5 mg/kg/d till repeating ‎cardiac echo. ‎Conclusion:‎ A high index of suspicion of KD must be maintained in young infants with ‎prolonged unexplained fever. Accepted criteria should be less restrictive to ‎allow early diagnosis of a typical KD in infants less than 6 months of age. ‎Timely appropriate treatment with IVIG is essential to avoid severe coronary ‎sequels.‎

Keywords: Kawasaki disease, atypical Kawasaki disease, infantile Kawasaki disease, hypo activity‎ ‎

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Authors: Ananya Hazare, Ranjit Kamble

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Introduction: Patients with Cleft lip and palate (CL/P) can present with a maxillary retrution after cleft repair. Anterior Maxillary distraction osteogenesis (AMD) is a technique that provides simultaneous skeletal advancement and expansion of the soft tissues related to an anterior segment of the maxilla. This case presented is a case of AMD. The advantage of this technique is that the occlusion in the posterior segment can be maintained, and only the segment in cross bite is advanced for correction of the midfacial deficiency. The other alternative treatment is anterior movement by a Lefort 1 osteotomy. When a Lefort 1 osteotomy is compared with the Distraction osteogenesis or AMD, the disadvantages of the Le Fort 1 include a higher risk of morbidity, requirement of fixation, relapse tendency and unexpected changes in the nasal form. These complications were eliminated by AMD technique. This was followed by placement of the implant in the bone formed after AMD. Hence complete surgical, orthodontic and prosthodontics rehabilitation of the patient was done by an interdisciplinary approach. Methods: Patient presented with repaired UCL/P of the right side with midfacial retrusion. Intro-oral examination revealed a good occlusion in the posterior arch and anterior Crossbite from canine to canine. Patient's both maxillary lateral incisors were missing. The lower arch was well aligned with all teeth present. The study models when scored according to GOSLON yardstick received a score of 4. After pre-surgical orthodontic phase was completed an intraoral distractor was fabricated by modification of HYRAX expansion screw. After surgery, low subapical osteotomy cuts were placed and the distractor was fixed. The latency period of 5 days was observed after which the distraction was started. Distraction was done at a rate of 1 mm/day with a rhythm of 0.5mm in morning and 0.5mm in the evening. The total distraction of 12 mm was done. After a consolidation period, the distractor was removed, and retention by a removable partial denture was given. Radiographic examination confirmed mature bone formation in the distracted segment. Implants were placed and allowed to osseointegrate for approximately 4 months and were then loaded with abutments. Results: Total distraction done was 12mm and after relapse it was 8mm. After consolidation phase the radiographic examination revealed a B2 quality of bone according to the Misch's classification and sufficient height from the maxillary sinus. These findings were indicative for placement of implants in the distracted bone formed in premolar region. Implants were placed and after radiographic evidence of osseointegration was seen they were loaded with abutments. Thus resulting in a complete rehabilitation of a cleft patient by an interdisciplinary approach. Conclusion: Anterior maxillary distraction can be used as an alternative method instead of complete distraction osteogenesis or Lefort 1 advancement of maxilla in cases where the advancement needed is minimum. Use of HYRAX expansion screw modified as intra-oral distractor can be used in such cases, which significantly reduces the cost of treatment, as expensive distractors are not used. This technique is very useful and efficient in countries like India where the patient cannot afford expensive treatment options.

Keywords: cleft lip and palate, distraction osteogenesis, anterior maxillary distraction, orthodontics and dentofacial orthopaedics, hyrax expansion screw modification

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Authors: Brayan Daniel Riascos Arteaga, Carlos Costa Perez

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Landfill leachate has an important fraction of humic substances, mainly humic acids (HAs), which often represent more than half value of COD, specially in liquids proceeded from composting processes of organic fraction of solid wastes. We propose in this article a new method of pH sensitive flocculation for COD and colour reduction in landfill leachate based on the chemical properties of HAs. Landfill leachate with a high content of humic acids can be efficiently treated by pH sensitive flocculation at pH 2.0, reducing COD value in 86.1% and colour in 84.7%. Mechanism of pH sensitive flocculation is based in protonation first of phenolic groups and later of carboxylic acid groups in the HAs molecules, resulting in a reduction of Zeta potential value. For pH over neutrality, carboxylic acid and phenolic groups are ionized and Zeta potential increases in absolute value, maintaining HAs in suspension as colloids and conducting flocculation to be obstructed. Ionized anionic groups (carboxylates) can interact electrostatically with cations abundant in leachate (site binding) aiding to maintain HAs in suspension. Simulation of this situation and ideal visualization of Zeta potential behavior is described in the paper and aggregation of molecules by H-bonds is proposed as the main step in separation of HAs from leachate and reduction of COD value in this complex liquid. CHNS analysis, FT-IR spectrometry and UV–VIS spectrophotometry show chemical elements content in the range of natural and commercial HAs, clear aromaticity and carboxylic acids and phenolic groups presence in the precipitate from landfill leachate

Keywords: landfill leachate, humic acids, COD, chemical treatment, flocculation

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Authors: Song Hung Chi, Lee Chun Benn

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Follow by the “A Research on Types of Settlement Housing Alterations of Chinese New Village in Malaysia- A Study in Ampang New Village, Selangor” preliminary informed that the main factors for expansion and enlargement suitably due to the needs of user's life and restoration purpose. The alterations behavior generally derived at the rear position of main house with different types of derivatives, the averages expansion area are not exceeding of 100㎡, while building materials used were wooden, wooden structure, and zinc which are non-permanent building materials. Therefore, a subsequent studies taken in this paper, further to analyze the drawing with summarize method, to explore the derived forms and the constituted rules of housing alterations in Ampang Village, as a more complete presentation of housing alterations in New Village. Firstly, classified the existing housing alterations into three types by using summarize method, which are Type 1, Additional of Prototype House; Type 2, Expansion of Prototype House; and Type 3, Diffusion of Additional. The results shows that the derivative mode of alterations can be divided into the use of "continuous wall" or "non-continuous wall," this will affects the structural systems and roof styles of alterations, and formed the different layers of interior space with "stages" and "continuity". On the aspects of spatial distribution, sacrificial area as a prescriptive function of space, it was mostly remains in the original location which in the center of living area after alterations. It is an important characteristic in a New Village house, reflecting the traditional Ethics of Hakka Chinese communities in the settlement. In addition, wooden as the main building materials of constituted rules for the prototype house, although there were appeared other building materials, such as cement, brick, glass, metal and zinc after alterations, but still mostly as "wooden house" pattern. Result show because of the economy of village does not significantly improve, and also forming the similarity types in alterations and constructions of the additional building with the existing. It did not significantly improve on the quality of living, but only increased the area of usage space.

Keywords: Ampang new village, derived forms, constituted rules, alterations

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Authors: Rakesh Tiwary, D. M. Diwakar, Sandhya Mahapatro

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Agro-forestry offers huge opportunities for diversification of agriculture in middle Gangetic Basin of India, particularly in the state of Bihar as the region is identified with traditional & stagnant agriculture, low productivity, high population pressure, rural poverty and lack of agro- industrial development. The region is endowed with favourable agro-climatic, soil & drainage conditions; interestingly, there has been an age old tradition of agro-forestry in the state. However, due to demographic pressures, declining land holdings and other socio- economic factors, agro forestry practices have declined in recent decades. The government of Bihar has initiated a special program for expansion of agro-forestry based on modern practices with an aim to raise income level of farmers, make available raw material for wood based industries and increase green cover in the state. The Agro-forestry Schemes – Poplar & Other Species are the key components of the program being implemented by Department of Environment & Forest, Govt. of Bihar. The paper is based on fieldwork based evaluation study on experiences of implementation of the agro-forestry schemes. Understanding adoption patterns, identification of key motives for practising agro-forestry, experiences of farmers well analysing the barriers in expansion constituted the major themes of the research study. This paper is based on primary as well as secondary data. The primary data consists of beneficiary household survey, Focus Group Discussions among beneficiary communities, dialogue and multi stakeholder meetings and field visit to the sites. The secondary data information was collected and analysed from official records, policy documents and reports. Primary data was collected from about 500 beneficiary households of Muzaffarpur & Saharsa- two populous, large and agriculture dominated districts of middle Gangetic basin of North Bihar. Survey also covers 100 households of non-beneficiaries. Probability Proportionate to Size method was used to determine the number of samples to be covered in different blocks of two districts. Qualitative tools were also implemented to have better insights about key research questions. Present paper discusses socio-economic background of farmers practising agro-forestry; the adoption patterns of agro- forestry (choice of plants, methods of plantation and others); and motivation behind adoption of agro-forestry and the comparative benefits of agro-forestry (vis-a-vis traditional agriculture). Experience of beneficiary farmers with agro-forestry based on government programs & promotional campaigns (in terms of awareness, ease of access, knowhow and others) have been covered in the paper. Different aspects of survival of plants have been closely examined. Non beneficiaries but potential adopters were also interviewed to understand barriers of adoption of agro- forestry. Paper provides policy recommendations and interventions required for effective expansion of the agro- forestry and realisation of its future prospects for agricultural diversification in the region.

Keywords: agro-forestry adoption patterns, farmers’ motivations & experiences, Indian middle Gangetic plains, strategies for expansion

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Authors: Gehan F. Abdel Raoof, Ataa A. Said, Khaled Y. Mohamed, Hala M. Mohammed

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Pleiogynium timorense(DC.) Leenh is one of the therapeutically active plants belonging to the family Anacardiaceae. The bark of Pleiogynium timorense needs further studies to investigate its phytochemical and biological activities. This work was carried out to investigate the chemical composition of petroleum ether extract of Pleiogynium timorense bark as well as to evaluate the analgesic and anti-inflammatory activities. The unsaponifiable matter and fatty acid methyl esters were analyzed by Gas chromatography–mass spectrometry (GC-MS). Moreover, analgesic and anti-inflammatory activities were evaluated using acetic acid-induced writhing test and carrageen hind paw oedema models in rats, respectively. The results showed that twenty one compounds in the unsaponifiable fraction were identified representing 92.54 % of the total beak area, the major compounds were 1-Heptene (35.32%), Butylated hydroxy toluene (19.42%) and phytol (12.53%), whereas fifteen compounds were identified in the fatty acid methyl esters fraction representing 94.15% of the total identified peak area. The major compounds were 9-Octadecenoic acid methyl ester (35.34%) and 9,12-Octadecadienoic acid methyl ester (29.32%). Moreover, petroleum ether extract showed a significant reduction in pain and inflammation in a dose dependent manner. This study aims to be the first step toward the use of petroleum ether extract of Pleiogynium timorense bark as analgesic and anti-inflammatory drug.

Keywords: analgesic, anti-inflammatory, bark, petroleum ether extract, Pleiogynium timorense

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Authors: S. Ngcinela, A. Mushunje, A. Taruvinga, C. S. Mutengwa, T. S. Masehela

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There is high demand and competing needs when it comes to land use practices. Several factors contribute to this trend, for example, the ever-increasing human population, the need to produce more food than before, and the expansion of industrial and agricultural areas. This paper, focused on the cultivation patterns, land use change over time, of maize and soybean (i.e. both genetically modified and non-genetically modified) in two South African provinces to establish their land cover changes over time. From a global context, genetically modified crops have been advocated by some to be saving land – due to more yield over small cultivation area(s); while other argue and even criticise their cultivation as they take up more land, replace other crops or are the expense of natural (pristine) vegetation. The study quantified and mapped land used for the cultivation of maize and soybean from 2006 to 2017 in Free State and North West provinces, using ArcGIS. The results show both provinces to have minimal expansion or change in cultivation area for both maize and soybean between 2006 and 2017. The results further indicate that both maize and soybean cultivation areas in these provinces, did not expand beyond the current agricultural areas (space), and did not encroach onto new land areas. This suggests that both maize and soybean, do not currently pose a threat to the surrounding landscape and are not in direct coemption with other neighboring land use practices.

Keywords: agriculture, crops, cultivation, genetically modified, land use, maize, soybean

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Authors: Lakshmi E. Jayachandran, Manepally Rajkumar, Pavuluri Srinivasa Rao

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The objective of this research was to study the changes in eating quality of rice during storage under varying temperature and moisture regimes. Paddy (IR-36) with high amylose content (27%) was stored at a temperature range between 10 to 40°C and moisture content from 9 to 18% (d.b.) for 6 months. Drastic changes in color and parameters representing cooking qualities, cooked rice texture, and surface morphology occurred after 4 months of storage, especially at elevated temperature conditions. Head rice yield was stable throughout the storage except at extreme conditions of temperature and moisture content. Yellowing of rice was prominent at combinations of high temperature and moisture content, both of which had a synergistic effect on the b* values of rice. The cooking time, length expansion ratio and volume expansion ratio of all the rice samples increased with prolonged storage. The texture parameter, primarily, the hardness, cohesiveness, and adhesiveness of cooked rice samples were higher following storage at elevated temperature. Surface morphology was also significantly affected in stored rice as compared to fresh rice. Storage of rice at 10°C with a grain moisture content of 10% for 2 months gave cooked rice samples with good palatability and minimal cooking time. The temperature was found to be the most prominent storage parameter for rough rice, followed by moisture content and storage duration, influencing the quality of rice.

Keywords: rice, cooking quality, storage, surface morphology

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Authors: Purba Biswas, Priyanka Dey

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Worldwide rapid urbanisation has accelerated city expansion in both developed and developing nations. This unprecedented urbanisation trend due to the increasing population and economic growth has caused challenges for the decision-makers in city planning and urban management. Metropolitan cities, class-I towns, and major urban centres undergo a continuous process of evolution due to interaction between socio-cultural and economic attributes. This constant evolution leads to urban expansion in all directions. Understanding the patterns and dynamics of urban built-up growth is crucial for policymakers, urban planners, and researchers, as it aids in resource management, decision-making, and the development of sustainable strategies to address the complexities associated with rapid urbanisation. Identifying spatio-temporal patterns of urban growth has emerged as a crucial challenge in monitoring and assessing present and future trends in urban development. Analysing urban growth patterns and tracking changes in land use is an important aspect of urban studies. This study analyses spatio-temporal urban transformations and land-use and land cover changes using remote sensing and GIS techniques. Built-up growth analysis has been done for the city of Surat as a case example, using the GIS tools of NDBI and GIS models of the Built-up Urban Density Index and Shannon Entropy Index to identify trends and the geographical direction of transformation from 2005 to 2020. Surat is one of the fastest-growing urban centres in both the state and the nation, ranking as the 4th fastest-growing city globally. This study analyses the dynamics of urban built-up area transformations both zone-wise and geographical direction-wise, in which their trend, rate, and magnitude were calculated for the period of 15 years. This study also highlights the need for analysing and monitoring the urban growth pattern of class-I cities in India using spatio-temporal and quantitative techniques like GIS for improved urban management.

Keywords: urban expansion, built-up, geographic information system, remote sensing, Shannon’s entropy

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Authors: Abdul Salam Turkmani

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The Lower Cretaceous rocks are exposed only in the mountains regions of Syria, such as the Anti- Lebanon mountain on the western side of Damascus. The lower cretaceous sequences are made up of different rocks. The upper and middle parts of the section are composed mainly of carbonate sediments and, less frequently, gypsum and anhydrite. The lower beds are mainly composed of sandstone, conglomerate and clay. Clay samples were collected from the study area, which is located about 45 km west of the city of Damascus, near the border village of Kfer Yabous and to the left of the Damascus -Beirut International Road, within the lower Cretaceous upper Aptian deposits. The properties of clay were carried out by X-ray diffraction (XRD) and, X-ray fluorescence (XRF) and Thermal Analysis (DTA-TG-DSC) techniques. The studied samples of clay were mainly composed of kaolinite, quartz, illite. Chemical analysis shows the content of SiO₂ varied between 46.06 to 73 % Al₂O₃ 14.55-26.56%, about the staining oxides (Fe₂O₃ + TiO₂), the total content is about 4.3 to 12.5%. The physical properties were determined by studying the behavior of the body before and after firing, showed low bending strength values (22.5 kg/cm²) after drying, and (about 247 kg/cm²) after firing at 1180°C, water absorption value was about 10%. The cubic thermal expansion coefficient at 1140°C is 213.77 x 10-7 /°C. All of the presented results confirm the suitability of this clay for the ceramic industry.

Keywords: anti-Lebanon, Damascus, ceramic, clay, thermal analysis, thermal expansion coefficient

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Authors: Nadine khadraoui, Rym Essid, Olfa Tabbene, Imen Chniba, Safa Boujemaa, Selim Jallouli, Nadia Fares, Behija Mlik, Boutheina Ben Abdelmoumen Mardassi

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Background and aim: Mycoplasma hominis is an opportunistic pathogen that can cause various gynecological infections such cervicitis, infertility, and, less frequently, extra-genital infections. Previous studies on the antimicrobial susceptibility of Mycoplasma hominis Tunisian strains have highlighted a significant resistance, even multi-resistance, to the most used antibiotic in the therapy of consequential infections. To address this concern, the present study aimed for the alternative of phytotherapy. Peganum harmala seed extract was tested as an antibacterial agent against multidrug-resistant M.hominis clinical strains. Material and Methods: Peganum harmala plant was collected from Ain Sebaa, Tabarka, North West region of Tunisia in April 2018, air-dried, grounded and extracted by different solvents.The crude methanolic extract was further partitioned with n-HEX, DCM, EtOAC and n-BuOl. Antibacterial activity was evaluated against M. hominis ATCC 23114 and 20 M. hominis clinical strains.The antimycoplasmal activity was tested by the microdilution method, and MIC values were determined. Phytochemical analysis and hemolytic activity on human erythrocytes were also performed. The active fraction was then subjected to purification, and the chemical identification of the active compound was investigated. Results: Among the tested fractions, the n-BuOH extract was the most active fraction since it exhibited an inhibitory effect against M. hominis ATCC 23114 and 80% of the tested clinical strains with MIC between 125 and 1000 µg/ml. The phytochemical analysis of the n-BuOH revealed its metabolic abundance in polyphenols, flavonoids and condensed tannin with levels of 257.37 mg AGE/g, 172.27 mg EC/g and 58.27 mg EC/g, respectively. In addition, P. harmala n-BuOH extract exhibited potent bactericidal activity against all M. hominis isolates with CMB values ranging between 125 and 4000 µg/ml. Further, the active fraction exhibited weak cytotoxicity effect at active concentrations when tested on human erythrocytes. The active compound was identified by gas chromatography–mass spectrometry as an indole alkaloid harmaline. Conclusion: In summary, Peganum harmala extract demonstrated an interesting anti-mycoplasmal activity against M. hominis Tunisian strains. Therefore, it could be considered as a potential candidate for the treatment of consequential infections. However, further studies are necessary to evaluate its mechanism of action in mycoplasmas.

Keywords: mycoplasma hominis, peganum harmala, antibioresistance, phytotherapy, phytochemical analysis

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Authors: G. Roshan Deen, J. S. Pedersen

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Temperature-responsive poly(N-isopropyl acrylamide) PNIPAM microgels crosslinked with a new hydrophobic chemical crosslinker was prepared by surfactant-mediated precipitation emulsion polymerization. The temperature-responsive property of the microgel and the influence of the crosslinker on the swelling behaviour was studied systematically by light scattering and small-angle X-ray scattering (SAXS). The radius of gyration (Rg) and the hydrodynamic radius (Rh) of the microgels decreased with increase in temperature due to the volume phase transition from a swollen to a collapsed state. The ratio of Rg/Rh below the transition temperature was lower than that of hard-spheres due to the lower crosslinking density of the microgels. The SAXS data was analysed by a model in which the microgels were modelled as core-shell particles with a graded interface. The model at intermediate temperatures included a central core and a more diffuse outer layer describing pending polymer chains with a low crosslinking density. In the fully swollen state, the microgels were modelled with a single component with a broad graded surface. In the collapsed state they were modelled as homogeneous and relatively compact particles. The polymer volume fraction inside the microgel was also derived based on the model and was found to increase with increase in temperature as a result of collapse of the microgel to compact particles. The polymer volume fraction in the core of the microgel in the collapsed state was about 60% which is higher than that of similar microgels crosslinked with hydrophilic and flexible cross-linkers.

Keywords: microgels, SAXS, hydrophobic crosslinker, light scattering

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Authors: A. Soualem

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The design of multi stage deep drawing processes requires the evaluation of many process parameters such as the intermediate die geometry, the blank shape, the sheet thickness, the blank holder force, friction, lubrication etc..These process parameters have to be determined for the optimum forming conditions before the process design. In general sheet metal forming may involve stretching drawing or various combinations of these basic modes of deformation. It is important to determine the influence of the process variables in the design of sheet metal working process. Especially, the punch and die corner for deep drawing will affect the formability. At the same time the prediction of sheet metals springback after deep drawing is an important issue to solve for the control of manufacturing processes. Nowadays, the importance of this problem increases because of the use of steel sheeting with high stress and also aluminum alloys. The aim of this paper is to give a better understanding of the springback and its effect in various sheet metals forming process such as expansion and restraint deep drawing in the cup drawing process, by varying radius die, lubricant for two commercially available materials e.g. galvanized steel and Aluminum sheet. To achieve these goals experiments were carried out and compared with other results. The original of our purpose consist on tests which are ensured by adapting a U-type stretching-bending device on a tensile testing machine, where we studied and quantified the variation of the springback.

Keywords: springback, deep drawing, expansion, restricted deep drawing

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Authors: Veena N. Hegde, S. R. Desai

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Motivating a heterogeneous group of students towards engagement in research related activities is a challenging task in engineering education. An effort is being made at the Department of Electronics and Instrumentation Engineering, where two courses are taken up on a pilot basis to kindle research interests in students at the undergraduate level. The courses, namely algorithm and system design (ASD) and automation in process control (APC), are selected for experimentation purposes. The task is being accomplished by providing scope for implementation of research papers and proposing solutions for the current industrial problems by the student teams. The course instructors have proposed an alternative assessment tool to evaluate the undergraduate students that involve activities beyond the curriculum. The method was tested for the aforementioned two courses in a particular academic year, and as per the observations, there is a considerable improvement in the number of student engagement towards research in the subsequent years of their undergraduate course. The student groups from the third-year engineering were made to read, implement the research papers, and they were also instructed to develop simulation modules for certain processes aiming towards automation. The target audience being students, were common for both the courses and the students' strength was 30. Around 50% of successful students were given the continued tasks in the subsequent two semesters, and out of 15 students who continued from sixth semesters were able to follow the research methodology well in the seventh and eighth semesters. Further, around 30% of the students out of 15 ended up carrying out project work with a research component involved and were successful in producing four conference papers. The methodology adopted is justified using a sample data set, and the outcomes are highlighted. The quantitative and qualitative results obtained through this study prove that such practices will enhance learning experiences substantially at the undergraduate level.

Keywords: industrial problems, learning experiences, research related activities, student engagement

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Authors: Farshid Fathinia

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This paper examines numerically the laminar steady magneto-hydrodynamic mixed convection flow and heat transfer in a wavy lid-driven cavity filled with water-Al2O3 nanofluid using FDM method. The left and right sidewalls of the cavity have a wavy geometry and are maintained at a cold and hot temperature, respectively. The top and bottom walls are considered flat and insulated while, the bottom wall moves from left to right direction with a uniform lid-driven velocity. A magnetic field is applied vertically downward on the bottom wall of the cavity. Based on the numerical results, the effects of the dominant parameters such as Rayleigh number, Hartmann number, solid volume fraction, and wavy wall geometry parameters are examined. The numerical results are obtained for Hartmann number varying as 0 ≤ Ha ≤ 0.6, Rayleigh numbers varying as 103≤ Ra ≤105, and the solid volume fractions varying as 0 ≤ φ ≤ 0.0003. Comparisons with previously published numerical works on mixed convection in a nanofluid filled cavity are performed and good agreements between the results are observed. It is found that the flow circulation and mean Nusselt number decrease as the solid volume fraction and Hartmann number increase. Moreover, the convection enhances when the amplitude ratio of the wavy surface increases. The results also show that both the flow and thermal fields are significantly affected by the amplitude ratio (i.e., wave form) of the wavy wall.

Keywords: nanofluid, mixed convection, magnetic field, wavy cavity, lid-driven, SPH method

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Authors: R. Sharma, S. Kumar, C. Sharma

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A number of toxic chlorophenolic compounds are formed during pulp bleaching. The nature and concentration of these chlorophenolic compounds largely depends upon the amount and nature of bleaching chemicals used. These compounds are highly recalcitrant and difficult to remove but are partially removed by the biochemical treatment processes adopted by the paper industry. Identification and estimation of these chlorophenolic compounds has been carried out in the primary and secondary clarified effluents from the paper mill by GCMS. Twenty-six chorophenolic compounds have been identified and estimated in paper mill waste waters. Electrochemical treatment is an efficient method for oxidation of pollutants and has successfully been used to treat textile and oil waste water. Electrochemical treatment using less expensive anode material, stainless steel electrodes has been tried to study their removal. The electrochemical assembly comprised a DC power supply, a magnetic stirrer and stainless steel (316 L) electrode. The optimization of operating conditions has been carried out and treatment has been performed under optimized treatment conditions. Results indicate that 68.7% and 83.8% of cholorphenolic compounds are removed during 2 h of electrochemical treatment from primary and secondary clarified effluent respectively. Further, there is a reduction of 65.1, 60 and 92.6% of COD, AOX and color, respectively for primary clarified and 83.8%, 75.9% and 96.8% of COD, AOX and color, respectively for secondary clarified effluent. EC treatment has also been found to increase significantly the biodegradability index of wastewater because of conversion of non- biodegradable fraction into biodegradable fraction. Thus, electrochemical treatment is an efficient method for the degradation of cholorophenolic compounds, removal of color, AOX and other recalcitrant organic matter present in paper mill waste water.

Keywords: chlorophenolics, effluent, electrochemical treatment, wastewater

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Authors: Laurentiu Moruz, Jens Kitzhofer, Mircea Dinulescu

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The paper aims to extend the knowledge about jet behavior and jet interaction between five plane unventilated jets with large aspect ratio (AR). The distance between the single plane jets is two times the channel height. The experimental investigation applies 2D Particle Image Velocimetry (PIV) and static pressure measurements. Our study focuses on the influence of two different outlet nozzle geometries (triangular shape with 2 x 7.5° and blunt geometry) with respect to variation of Reynolds number from 5500 - 12000. It is shown that the outlet geometry has a major influence on the jet formation in terms of uniformity of velocity profiles downstream of the sudden expansion. Furthermore, we describe characteristic regions like converging region, merging region and combined region. The triangular outlet geometry generates most uniform velocity distributions in comparison to a blunt outlet nozzle geometry. The blunt outlet geometry shows an unstable behavior where the jets tend to attach to one side of the walls (ceiling) generating a large recirculation region on the opposite side. Static pressure measurements confirm the observation and indicate that the recirculation region is connected to larger pressure drop.

Keywords: 2D particle image velocimetry, parallel jet interaction, pressure drop, sudden expansion

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Authors: Evln Ranga Charyulu, S. P. Venu Madhavarao, S. Udaya kumar, S. V. S. S. N. V. G. Krishna Murthy

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With the advent of new nanometer process technologies, it is possible to integrate billion transistors on a single substrate. When more and more functionality included there is the possibility of multi-million transistors switching simultaneously consuming more power and dissipating more power along with more leakage of current into the substrate of porous silicon or germanium material. These results in substrate heating and thermal noise generation coupled to signals of interest. The heating process is represented by coupled nonlinear partial differential equations in porous silicon and germanium. By identifying heat sources and heat fluxes may results in designing of ultra-low power circuits. The PDEs are solved by finite difference scheme assuming that boundary layer equations in porous silicon and germanium. Local heat fluxes along the vertical isothermal surface immersed in porous SI/Ge are considered. The parameters considered for optimization are thermal diffusivity, thermal expansion coefficient, thermal diffusion ratio, permeability, specific heat at constant temperatures, Rayleigh number, amplitude of wavy surface, mass expansion coefficient. The diffusion of heat was caused by the concentration gradient. Thermal physical properties are homogeneous and isotropic. By using L8, TAGUCHI method the parameters are optimized.

Keywords: heat transfer, pde, taguchi optimization, SI/Ge

Procedia PDF Downloads 317

Authors: Nani Mchedlishvili, Nino Omiadze, Marine Abutidze, Jose Neptuno Rodriguez-Lopez, Tinatin Sadunishvili, Nikoloz Pruidze, Giorgi Kvesitadze

Abstract:

Recently, there is an increased interest in the development of food natural colorants as alternatives to synthetic dyes because of both legislative action and consumer concern. Betalains are widely used in the food industry as an alternative of synthetic colorants. The interest of betalains are caused not only by their coloring effect but also by their beneficial properties. The aim of the work was to study of stability of crude and purified red pigments of pokeberry (Phytolacca america L.). The pokeberry fruit juice was filtrated and concentrated by rotary vacuum evaporator up to 25% and the concentrated juice was passed through the Sepadex-25(fine) column (20×1.1 cm). From the column the pigment elution rate was 18 ml/hr. 1.5ml fractions of pigment were collected. In the fractions the coloring substances were determined using CuS04 x 7 H2O as a standard. From the Sephadex G-25 column only one fraction of the betalain red pigment was eluted with the absorption maximum at 538 nm. The degree of pigment purification was 1.6 and pigment yield from the column was 15 %. It was shown that thermostability of pokeberry fruit red pigment was significantly decreased after the purification. For example, during incubation at 100C for 10 min crude pigment retained 98 % of its color while under the same conditions only 72% of the color of purified pigment was retained. The purified pigment was found to be characterized by less storage stability too. The storage of the initial crude juice and the pigment fraction obtained after the gelfiltration for 10 days at 4°C showed the lost of color by 29 and 74 % respectively. From the results obtained, it can be concluded that during the gelfiltration the pokeberry fruit red pigment gets separated from such substances that cause its stabilization in the crude juice.

Keywords: betalains, gelfiltration, pokeberry fruit, stability

Procedia PDF Downloads 274

Authors: Saeed Bagherifam, Trevor Brown, Chris Fellows, Ravi Naidu

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Over the last century, rapid urbanization, industrial emissions, and mining activities have resulted in widespread contamination of the environment by heavy metal(loid)s. Arsenic (As) is a toxic metalloid belonging to group 15 of the periodic table, which occurs naturally at low concentrations in soils and the earth’s crust, although concentrations can be significantly elevated in natural systems as a result of dispersion from anthropogenic sources, e.g., mining activities. Bioavailability is the fraction of a contaminant in soils that is available for uptake by plants, food chains, and humans and therefore presents the greatest risk to terrestrial ecosystems. Numerous attempts have been made to establish in situ and ex-situ technologies of remedial action for remediation of arsenic-contaminated soils. In situ stabilization techniques are based on deactivation or chemical immobilization of metalloid(s) in soil by means of soil amendments, which consequently reduce the bioavailability (for biota) and bioaccessibility (for humans) of metalloids due to the formation of low-solubility products or precipitates. This study investigated the effectiveness of two different types of synthetic manganese and iron oxides (birnessite and goethite) for stabilization of As in a soil spiked with 1000 mg kg⁻¹ of As and treated with 10% dosages of soil amendments. Birnessite was made using HCl and KMnO₄, and goethite was synthesized by the dropwise addition of KOH into Fe(NO₃) solution. The resulting contaminated soils were subjected to a series of chemical extraction studies including sequential extraction (BCR method), single-step extraction with distilled (DI) water, 2M HNO₃ and simplified bioaccessibility extraction tests (SBET) for estimation of bioaccessible fractions of As in two different soil fractions ( < 250 µm and < 2 mm). Concentrations of As in samples were measured using inductively coupled plasma mass spectrometry (ICP-MS). The results showed that soil with birnessite reduced bioaccessibility of As by up to 92% in both soil fractions. Furthermore, the results of single-step extractions revealed that the application of both birnessite and Goethite reduced DI water and HNO₃ extractable amounts of arsenic by 75, 75, 91, and 57%, respectively. Moreover, the results of the sequential extraction studies showed that both birnessite and goethite dramatically reduced the exchangeable fraction of As in soils. However, the amounts of recalcitrant fractions were higher in birnessite, and Goethite amended soils. The results revealed that the application of both birnessite and goethite significantly reduced bioavailability and the exchangeable fraction of As in contaminated soils, and therefore birnessite and Goethite amendments might be considered as promising adsorbents for stabilization and remediation of As contaminated soils.

Keywords: arsenic, bioavailability, in situ stabilisation, metalloid(s) contaminated soils

Procedia PDF Downloads 113

Authors: Siphat Lim

Abstract:

This study used Autoregressive Distributed Lag (ARDL) approach to cointegration. In the long-run the general price level and exchange rate have a positively significant effect on domestic output. The estimated result further revealed that fiscal stimulus help stimulate domestic output in the long-run, but not in the short-run, while monetary expansion help to stimulate output in both short-run and long-run. The result is complied with the theory which is the macroeconomic policies, fiscal and monetary policy; help to stimulate domestic output in the long-run. The estimated result of the Vector Error Correction Model (VECM) has indicated more clearly that the consumer price index has a positive effect on output with highly statistically significant. Increasing in the general price level would increase the competitiveness among producers than increase in the output. However, the exchange rate also has a positive effect and highly significant on the gross domestic product. The exchange rate depreciation might increase export since the purchasing power of foreigners has increased. More importantly, fiscal stimulus would help stimulate the domestic output in the long-run since the coefficient of government expenditure is positive. In addition, monetary expansion would also help stimulate the output and the result is highly significant. Thus, fiscal stimulus and monetary expansionary would help stimulate the domestic output in the long-run in Cambodia.

Keywords: fiscal policy, monetary policy, ARDL, VECM

Procedia PDF Downloads 403

Authors: Fernando Maass, Pablo Martin, Jorge Olivares

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The Bessel function J₀(x) is very important in Electrodynamics and Physics, as well as its zeros. In this work, a method to obtain high accuracy approximation is presented through an application to that function. In most of the applications of this function, the values of the zeros are very important. In this work, analytic approximations for this function have been obtained valid for all positive values of the variable x, which have high accuracy for the function as well as for the zeros. The approximation is determined by the simultaneous used of the power series and asymptotic expansion. The structure of the approximation is a combination of two rational functions with elementary functions as trigonometric and fractional powers. Here us in Pade method, rational functions are used, but now there combined with elementary functions us fractional powers hyperbolic or trigonometric functions, and others. The reason of this is that now power series of the exact function are used, but together with the asymptotic expansion, which usually includes fractional powers trigonometric functions and other type of elementary functions. The approximation must be a bridge between both expansions, and this can not be accomplished using only with rational functions. In the simplest approximation using 4 parameters the maximum absolute error is less than 0.006 at x ∼ 4.9. In this case also the maximum relative error for the zeros is less than 0.003 which is for the second zero, but that value decreases rapidly for the other zeros. The same kind of behaviour happens for the relative error of the maximum and minimum of the functions. Approximations with higher accuracy and more parameters will be also shown. All the approximations are valid for any positive value of x, and they can be calculated easily.

Keywords: analytic approximations, asymptotic approximations, Bessel functions, quasirational approximations

Procedia PDF Downloads 229

Authors: M. F. Amado, A. Amado, F. Poggi, J. Correia de Freitas

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Today it is widely understood that global energy consumption patterns are directly related to the ongoing urban expansion and development process. This expansion is based on the natural growth of human activities and has left most urban areas totally dependent on fossil fuel derived external energy inputs. This status-quo of production, transportation, storage and consumption of energy has become inefficient and is set to become even more so when the continuous increases in energy demand are factored in. The territorial management of land use and related activities is a central component in the search for more efficient models of energy use, models that can meet current and future regional, national and European goals. In this paper, a methodology is developed and discussed with the aim of improving energy efficiency at the municipal level. The development of this methodology is based on the monitoring of energy consumption and its use patterns resulting from the natural dynamism of human activities in the territory and can be utilized to assess sustainability at the local scale. A set of parameters and indicators are defined with the objective of constructing a systemic model based on the optimization, adaptation and innovation of the current energy framework and the associated energy consumption patterns. The use of the model will enable local governments to strike the necessary balance between human activities, economic development, and the local and global environment while safeguarding fairness in the energy sector.

Keywords: solar urban planning, solar smart city, urban development, energy efficiency

Procedia PDF Downloads 306

Authors: Ahmad Sharif Ahmadi, Yoshitaka Kajita

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Kabul, the capital and largest city in Afghanistan has been experiencing a massive population expansion and fast economic development in last decade, in which urban land has increasingly expanded and formed a high informal development territory in the city. This paper investigates the urban land development direction based on the integrated urbanization trends in Kabul city since the last and the fastest ever urban land growth period (1999-2008), which is parallel with the establishment of the new government in Afghanistan. Considering the existing challenges in terms of informal settlements, squatter settlements, the population expansion of the city, and fast economic development, as well as the huge influx of returning refugees from neighboring countries, and the sprawl direction of urbanization of the Kabul city urban fringes, this research focuses on the possible urban land development direction and trends for the city. The paper studies the feasible future land development direction of Kabul city in the northern part called Shamali basin, in which district 17 is the gateway for future development. The area has much developable area including eight districts of Kabul province, and the vast area of Parwan and Kapisa provinces. The northern area of the Kabul city generally has favorable conditions for further urbanization from the city. It is a large and relatively flat area of area in the northern part of Kabul city, with ample water resources available from the Panjshir basin as a base principle of land development direction in the area.

Keywords: Kabul city, land development trends, urban land development, urbanization

Procedia PDF Downloads 257

Authors: Elena M. Kopteva, Pavlina Jaluvkova, Zdenek Stuchlik

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In spite of the numerous attempts to close the discussion about the influence of cosmological expansion on local gravitationally bounded systems, this question arises in literature again and again and remains still far from its final resolution. Here one of the main problems is the problem of obtaining a physically adequate model of strongly gravitating object immersed in non-static cosmological background. Such objects are usually called ‘cosmological’ black holes and are of great interest in wide set of cosmological and astrophysical areas. In this work the set of new exact solutions of the Einstein equations is derived for the flat space that generalizes the known Lemaitre-Tolman-Bondi solution for the case of nonzero pressure. The solutions obtained are pretending to describe the black hole immersed in nonstatic cosmological background and give a possibility to investigate the hot problems concerning the effects of the cosmological expansion in gravitationally bounded systems, the structure formation in the early universe, black hole thermodynamics and other related problems. It is shown that each of the solutions obtained contains either the Reissner-Nordstrom or the Schwarzschild black hole in the central region of the space. It is demonstrated that the approach of the mass function use in solving of the Einstein equations allows clear physical interpretation of the resulting solutions, that is of much benefit to any their concrete application.

Keywords: exact solutions of the Einstein equations, cosmological black holes, generalized Lemaitre-Tolman-Bondi solutions, nonzero pressure

Procedia PDF Downloads 400

Authors: Sabrina N. Rabelo, Tiago de F. Paulino, Willian M. Duarte, Samer Sawalha, Luiz Machado

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Energy use is one of the main indicators for the economic and social development of a country, reflecting directly in the quality of life of the population. The expansion of energy use together with the depletion of fossil resources and the poor efficiency of energy systems have led many countries in recent years to invest in renewable energy sources. In this context, solar-assisted heat pump has become very important in energy industry, since it can transfer heat energy from the sun to water or another absorbing source. The direct-expansion solar assisted heat pump (DX-SAHP) water heater system operates by receiving solar energy incident in a solar collector, which serves as an evaporator in a refrigeration cycle, and the energy reject by the condenser is used for water heating. In this paper, a DX-SAHP using carbon dioxide as refrigerant (R744) was assembled, and the influence of the variation of the water mass flow rate in the system was analyzed. The parameters such as high pressure, water outlet temperature, gas cooler outlet temperature, evaporator temperature, and the coefficient of performance were studied. The mainly components used to assemble the heat pump were a reciprocating compressor, a gas cooler which is a countercurrent concentric tube heat exchanger, a needle-valve, and an evaporator that is a copper bare flat plate solar collector designed to capture direct and diffuse radiation. Routines were developed in the LabVIEW and CoolProp through MATLAB software’s, respectively, to collect data and calculate the thermodynamics properties. The range of coefficient of performance measured was from 3.2 to 5.34. It was noticed that, with the higher water mass flow rate, the water outlet temperature decreased, and consequently, the coefficient of performance of the system increases since the heat transfer in the gas cooler is higher. In addition, the high pressure of the system and the CO₂ gas cooler outlet temperature decreased. The heat pump using carbon dioxide as a refrigerant, especially operating with solar radiation has been proven to be a renewable source in an efficient system for heating residential water compared to electrical heaters reaching temperatures between 40 °C and 80 °C.

Keywords: water mass flow rate, R-744, heat pump, solar evaporator, water heater

Procedia PDF Downloads 151

Authors: Sultan Z. Mahmud, Emily C. Graff, Adil Bashir

Abstract:

Phosphoprotein enriched in astrocytes 15 kDa (PEA-15) is a multifunctional adapter protein which is associated with the regulation of apoptotic cell death. Recently it has been discovered that PEA-15 is crucial in normal neurodevelopment of domestic cats, a gyrencephalic animal model, although the exact function of PEA-15 in neurodevelopment is unknown. This study investigates how PEA-15 affects the blood-brain barrier (BBB) permeability in cat brain, which can cause abnormalities in tissue metabolite and energy supplies. Severe polymicrogyria and microcephaly have been observed in cats with a loss of function PEA-15 mutation, affecting the normal neurodevelopment of the cat. This suggests that the vital role of PEA-15 in neurodevelopment is associated with gyrification. Neurodevelopment is a highly energy demanding process. The mammalian brain depends on glucose as its main energy source. PEA-15 plays a very important role in glucose uptake and utilization by interacting with phospholipase D1 (PLD1). Mitochondria also plays a critical role in bioenergetics and essential to supply adequate energy needed for neurodevelopment. Cerebral blood flow regulates adequate metabolite supply and recent findings also showed that blood plasma contains mitochondria as well. So the BBB can play a very important role in regulating metabolite and energy supply in the brain. In this study the blood-brain permeability in cat brain was measured using MRI magnetization transfer (MT) effect on the perfusion signal. Perfusion is the tissue mass normalized supply of blood to the capillary bed. Perfusion also accommodates the supply of oxygen and other metabolites to the tissue. A fraction of the arterial blood can diffuse to the tissue, which depends on the BBB permeability. This fraction is known as water extraction fraction (EF). MT is a process of saturating the macromolecules, which has an effect on the blood that has been diffused into the tissue while having minimal effect on intravascular blood water that has not been exchanged with the tissue. Measurement of perfusion signal with and without MT enables to estimate the microvascular blood flow, EF and permeability surface area product (PS) in the brain. All the experiments were performed with Siemens 7T Magnetom with 32 channel head coil. Three control cats and three PEA-15 mutant cats were used for the study. Average EF in white and gray matter was 0.9±0.1 and 0.86±0.15 respectively, perfusion in white and gray matter was 85±15 mL/100g/min and 97±20 mL/100g/min respectively, PS in white and gray matter was 201±25 mL/100g/min and 225±35 mL/100g/min respectively for control cats. For PEA-15 mutant cats, average EF in white and gray matter was 0.81±0.15 and 0.77±0.2 respectively, perfusion in white and gray matter was 140±25 mL/100g/min and 165±18 mL/100g/min respectively, PS in white and gray matter was 240±30 mL/100g/min and 259±21 mL/100g/min respectively. This results show that BBB is compromised in PEA-15 mutant cat brain, where EF is decreased and perfusion as well as PS are increased in the mutant cats compared to the control cats. This findings might further explain the function of PEA-15 in neurodevelopment.

Keywords: BBB, cat brain, magnetization transfer, PEA-15

Procedia PDF Downloads 119

Authors: Suja S. Nayar, Mayuri Pandya

Abstract:

The foundation of legal system of any nation is its constitution and the strive to achieve equality amongst different classes prevailing in the social system. The most traditional form of inequality that is prevailing in the society is the gender inequality. The existence of inequality on the basis of gender prevails since the ancient era which has with the passing time merely continued and aggravated to a great extent. The founding fathers of our constitution were well aware of the then prevailing situation and being concerned about the future if this inequality continued to prevail, and in such view, the provisions of Article 14, 15, 38 and 44 of our Constitution were enacted with specific intent for the upliftment of women. The strive for equality is the rule of law embodied with the principle of foreseeability which is necessitated in the stability of justice system of any nation, and when it comes to equality, the first form of equality we need to achieve is gender equality. Time and again various initiatives have been announced and attempted to achieve the objective of gender equality, but analysis of the ground reality always have yielded disappointing results. The research that is proposed to be undertaken intends to cover all the above issues concerning the failures ineffective implementation of the gender-specific laws especially the provisions concerning the protection provided under Domestic Violence Act. The researchers will analyze the judgment of last five years' judgments of Supreme Court of India. In Hiral P. Harsora and ors. v Kusum Narottamdas Harsora and Ors. the Hon'ble Supreme Court recently deleting the words 'adult male' from the definition of respondent disclosed it is intent and understanding that domestic violence is being caused by a female on female also and not only restricted to males on females only. The procedure as prescribed under the act for claiming reliefs though is as per the criminal mandate, but the reliefs are of civil nature and so same needs to deal emphatically which now makes it a lengthier process. The pros and cons of such pronouncements are being weighed on the balance of constitution and social equality that is strived by the entire women fraternity.

Keywords: domestic, violence, constitution, gender, equality, women

Procedia PDF Downloads 482

Authors: T. Garba, Y. Y. Sabo A. Babanyara, K. G. Ilellah, A. K. Mutari

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This study used the Normalized Difference Vegetation Index (NDVI) and maps compiled from the classification of Landsat TM and Landsat ETM images of 1986 and 1999 respectively and Nigeria sat 1 images of 2007 to quantify changes in land use and land cover in selected areas of Nigeria covering 143,609 hectares that are threatened by the encroaching Sahara desert. The results of this investigation revealed a decrease in natural vegetation over the three time slices (1986, 1999 and 2007) which was characterised by an increase in high positive pixel values from 0.04 in 1986 to 0.22 and 0.32 in 1999 and 2007 respectively and, a decrease in natural vegetation from 74,411.60ha in 1986 to 28,591.93ha and 21,819.19ha in 1999 and 2007 respectively. The same results also revealed a periodic trend in which there was progressive increase in the cultivated area from 60,191.87ha in 1986 to 104,376.07ha in 1999 and a terminal decrease to 88,868.31ha in 2007. These findings point to expansion of vegetated and cultivated areas in in the initial period between 1988 and 1996 and reversal of these increases in the terminal period between 1988 and 1996. The study also revealed progressive expansion of built-up areas from 1, 681.68ha in 1986 to 2,661.82ha in 1999 and to 3,765.35ha in 2007. These results argue for the urgent need to protect and conserve the depleting natural vegetation by adopting sustainable human resource use practices i.e. intensive farming in order to minimize persistent depletion of natural vegetation.

Keywords: changes, classification, desertification, vegetation changes

Procedia PDF Downloads 370