Parameter expansions in sonic boom theory

An approach based on parameter expansions is used to study some aspects of the sonic boom problem. The particular case of an accelerating or decelerating aircraft in level flight is considered. The main interest is in the far-field region. The effects of unsteady motion of the aircraft and non-linear propagation of the associated disturbance are introduced by defining appropriate frequency and amplitude parameters

Weather effect considerations in reliability evaluation of electrical transmission and distribution systems

The weather environment has a significant impact on the reliability of a power system due to its effect on the system failure mechanisms of overhead circuits and on the operational ability of an electric power utility. The physical stresses created by weather increase the failure rates of transmission or distribution lines operating in adverse weather conditions, resulting in increased coincident failures of multiple circuits. Exceptionally severe weather can cause immense system damages and significantly impact the reliability performance. Recognition of the pertinent weather impacts clearly indicates the need to develop appropriate models and techniques that incorporate variable weather conditions for realistic estimation of reliability indices. This thesis illustrates a series of multi-state weather models that can be utilized for predictive reliability assessment incorporating adverse and extremely adverse weather conditions. The studies described in this thesis are mainly focused on the analyses using the three state weather model. A series of multi-state weather models are developed and utilized to assess reliability performance of parallel redundant configurations. The application of weather modeling in reliability evaluation is illustrated using a practical transmission system. The thesis presents an approach to identify weather specific contributions to system reliability indices and illustrates the technique by utilizing a test distribution system. The analysis of a range of reliability distributions with regard to major event day segmentation is presented.The research work illustrated in this thesis clearly illustrates that reliability indices estimated without recognition of weather situations are unrealistic and that at minimum the three state weather model should be applied in reliability evaluation of systems residing in varying weather environments. The conclusions, concepts and techniques presented in this thesis should prove useful in practical application

Exploring potential of freshwater microalgae in Northern Ontario for bioremediation and bioenergy production

Native freshwater microalgae play a crucial role in biofuel production due to their unique characteristics and environmental suitability. This study investigated the diversity of microalgae species in various freshwater ecosystems across Northwestern Ontario, Canada and evaluated the nutrient removal, bioremediation and subsequent biomolecule production. Microalgae are known for their biochemical diversity, synthesizing an extensive range of compounds including proteins, lipids, carbohydrates, vitamins, pigments, and bioactive molecules In Chapter One, we provided a comprehensive review on the microalgae cultivation and harvesting techniques along with pretreatment methods for the extraction of biomolecules. In Chapter Two, we isolated 75 potential microalgal isolates and characterized these stains to identify those with high potential for lipid and biomolecule production capacity through a combination of microscopy, molecular techniques, and biochemical analysis and identified the optimal light condition for the biomass and lipid production. Among these isolated strains, a five microalgae strains with higher lipid production and growth were identified using molecular and morphological approaches. Among four different photoperiods, 16L:8D light/dark cycle produced significantly higher biomass and lipids for Chlorella sorokiniana, Chlorella vulgaris, and Chlamydomonas sp. [...

AN EFFICIENT DERIVATIVE FREE ITERATIVE METHOD FOR SOLVING SYSTEMS OF NONLINEAR EQUATIONS

We present a derivative free method of fourth order convergence for solving systems of nonlinear equations. The method consists of two steps of which first step is the well-known Traub's method. First-order divided difference operator for functions of several variables and direct computation by Taylor's expansion are used to prove the local convergence order. Computational efficiency of new method in its general form is discussed and is compared with existing methods of similar nature. It is proved that for large systems the new method is more efficient. Some numerical tests are performed to compare proposed method with existing methods and to confirm the theoretical results

On a class of efficient higher order Newton-like methods

Based on a two-step Newton-like scheme, we propose a three-step scheme of convergence order p+2 (p >=3) for solving systems of nonlinear equations. Furthermore, on the basis of this scheme a generalized k+2-step scheme with increasing convergence order p+2k is presented. Local convergence analysis including radius of convergence and uniqueness results of the methods is presented. Computational efficiency in the general form is discussed. Theoretical results are verified through numerical experimentation. Finally, the performance is demonstrated by the application of the methods on some nonlinear systems of equations

Remediation of Bagmati River water using activated carbon from Macrotyloma uniflorum (gram horse) seed

Remediation is a technique that facilitates the removable of pollutants from contaminated water. Activated carbons were prepared from indigenous Macrotyloma uniflorum (gram horse) seed using orthophosphoric acid as an activating agent. The chemically activated gram horse seed powder was carbonized using muffle furnace and characterized using thermo-gravimetric analysis (TGA), x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Boehm titration, methylene blue and iodine numbers. XRD and FTIR spectra indicated that the surface of amorphous activated carbon consisted of acidic and basic functional groups which efficiently adsorb pollutants from the polluted river water. The observed methylene blue and iodine numbers suggested that an impregnation ratio of 1.26:1, three hours of carbonization duration and carbonization temperature of 300 °C were the optimum conditions for the development of micro and mesopores on the surface of the activated carbon prepared from gram horse powder. The maximum adsorption capacity of methylene blue was 312.5 mg/g and that of iodine was 1006.2 mg/g and specific surface area was 1160.44 m2 /g. The both Langmuir and Freundlich model fit well in the methylene blue adsorption. A simple column filtration was used for the purification of river water. Most of the observed water quality parameters of the sample collected from the Bagmati River exceeded the limit recommended by WHO. However, after treatment with gram horse activated carbon, concentrations of measured parameters were reduced to WHO recommended value. More than 60% of the hardness, sulphate and phosphate concentrations were removed and more than 40% of alkalinity and chlorine demand were reduced by activated carbon. Based on the results it is considered that activated carbon from gram horse seed can be an effectively used as bio-adsorbent for the remediation of highly polluted river water. BIBECHANA 19(2022)170-18

Remediation of Bagmati River water using activated carbon from Macrotyloma uniflorum (gram horse) seed

Remediation is a technique that facilitates the removable of pollutants from contaminated water. Activated carbons were prepared from indigenous Macrotyloma uniflorum (gram horse) seed using orthophosphoric acid as an activating agent. The chemically activated gram horse seed powder was carbonized using muffle furnace and characterized using thermo-gravimetric analysis (TGA), x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Boehm titration, methylene blue and iodine numbers. XRD and FTIR spectra indicated that the surface of amorphous activated carbon consisted of acidic and basic functional groups which efficiently adsorb pollutants from the polluted river water. The observed methylene blue and iodine numbers suggested that an impregnation ratio of 1.26:1, three hours of carbonization duration and carbonization temperature of 300 °C were the optimum conditions for the development of micro and mesopores on the surface of the activated carbon prepared from gram horse powder. The maximum adsorption capacity of methylene blue was 312.5 mg/g and that of iodine was 1006.2 mg/g and specific surface area was 1160.44 m2 /g. The both Langmuir and Freundlich model fit well in the methylene blue adsorption. A simple column filtration was used for the purification of river water. Most of the observed water quality parameters of the sample collected from the Bagmati River exceeded the limit recommended by WHO. However, after treatment with gram horse activated carbon, concentrations of measured parameters were reduced to WHO recommended value. More than 60% of the hardness, sulphate and phosphate concentrations were removed and more than 40% of alkalinity and chlorine demand were reduced by activated carbon. Based on the results it is considered that activated carbon from gram horse seed can be an effectively used as bio-adsorbent for the remediation of highly polluted river water. BIBECHANA 19(2022)170-18

Securing Land Rights for All through Fit-for-Purpose Land Administration Approach:The Case of Nepal

After the political change in Nepal of 1951, leapfrog land policy improvements have been recorded, however, the land reform initiatives have been short of full success. Despite a land administration system based on cadaster and land registries in place, 25% of the arable land with an estimated 10 million spatial units on the ground are informally occupied and are off-register. Recently, a strong political will has emerged to ensure land rights for all. Providing tenure security to all these occupants using the conventional surveying and land administration approach demands a large amount of skilled human resources, a long timeframe and a huge budget. To assess the suitability of the fit-for-purpose land administration (FFPLA) approach for nationwide mapping and registration of informality in the Nepalese context, the identification, verification and recordation (IVR) of the people-to-land relationship was conducted through two pilot studies using a participatory approach covering around 1500 and 3400 parcels, respectively, in an urban and a rural setting. The pilot studies were based on the FFPLA National Strategy and utilized satellite imageries and smartphones for identification and verification of land boundaries. Data collection to verification tasks were completed within seven months in the urban settlements and for an average cost of 7.5 USD per parcel; within the rural setting, the pilot study was also completed within 7 months and for an average cost of just over 3 USD per parcel. The studies also informed the discussions on building the legislative and institutional frameworks, which are now in place. With locally trained ‘grassroots surveyors’, the studies have provided a promising alternative to the conventional surveying technologies by providing a fast, inexpensive and acceptable solution. The tested approach may fulfill the commitment to resolve the countrywide mapping of informality. The use of consistent data model and mapping standards are recommended

MaMADS2 repression in banana fruits modifies hormone synthesis and signalling pathways prior to climacteric stage

Background: While the role of ethylene in fruit ripening has been widely studied, the contributions of additional plant hormones are less clear. Here we examined the interactions between the transcription factor MaMADS2-box which plays a major role in banana fruit ripening and hormonal regulation. Specifically, we used MaMADS2 repressed lines in transcriptome and hormonal analyses throughout ripening and assessed hormone and gene expression perturbations as compared to wild-type (WT) control fruit. Results: Our analyses revealed major differences in hormones levels and in expression of hormone synthesis and signaling genes mediated by MaMADS2 especially in preclimacteric pulp. Genes encoding ethylene biosynthesis enzymes had lower expression in the pulp of the repressed lines, consistent with reduced ethylene production. Generally, the expression of other hormone (auxin, gibberellins, abscisic acid, jasmonic acid and salicylic acid) response pathway genes were down regulated in the WT pulp prior to ripening, but remained high in MaMADS2 repressed lines. Hormone levels of abscisic acid were also higher, however, active gibberellin levels were lower and auxin levels were similar with MaMADS2 repression as compared to WT. Although abscisic level was higher in MaMADS2 repression, exogenous abscisic acid shortened the time to ethylene production and increased MaMADS2 mRNA accumulation in WT. Exogenous ethylene did not influence abscisic acid level. CRE - a cytokinin receptor, increased its expression during maturation in WT and was lower especially at prebreaker in the repressed line and zeatin level was lower at mature green of the repressed line in comparison to WT. Conclusions: In addition to previously reported effects of MaMADS2 on ethylene, this transcription factor also influences other plant hormones, particularly at the pre-climacteric stage. The cytokinin pathway may play a previously unanticipated role via MaMADS2 in banana ripening. Finally, abscisic acid enhances MaMADS2 expression to promote ripening, but the transcription factor in turn auto inhibits ABA synthesis and signaling. Together, these results demonstrate a complex interaction of plant hormones and banana fruit ripening mediated by MaMADS2

Prevalence of intestinal parasites in humans and domestic animals in Jirel community, Dolakha, Nepal

ABSTRACT : Introduction:: Gastrointestinal (GI) parasites are major health concerns in both humans and domestic animals. Livestock farming is one of the common livelihood practices in rural Nepal. The proximity at human and domestic animal interface increases the chances of dissemination of enteric parasites, especially those of zoonotic importance. This study was aimed at finding the parasite prevalence and risk factors in both humans and their domestic animals in Jirel community. Materials and Methods:: A field survey was conducted on the Jirel ethnic people and their domestic animals in Dolakha district, where a total of 152 fresh fecal samples from humans and domestic animals (cow, pigs, goats, chickens, ducks, and pigeons) were collected. The feces were examined by wet mounts and concentration techniques. A structured questionnaire survey was carried out among the local people and owners of the domestic animals to gather sociodemographic information, awareness, and hygienic practices in relation to parasite transmission Results:: The enteric parasite prevalence was found to be highest in goats (80.0%;12/15), followed by pigs (55.55%;5/9), cows (45.45%;6/11), chickens (11.7%;4/34), and humans (1.41%;1/71), while the fecal samples of ducks and pigeons did not contain any parasites. The only parasite identified in humans was Ascaris lumbricoides. Similarly, three genera of GI parasites (Eimeria sp., Strongyloides sp, and Trichuris sp.) from goats, two genera each from cow (Eimeria sp. and Strongyloides sp.), pigs (Entamoeba sp. and A. suum), and chickens (Eimeria sp. and Ascaridia galli), were detected Conclusions:: Based on the direct field observation, questionnaire survey and laboratory analysis, it is concluded that the Jirel community people are aware of health and hygiene; however, intervention measures are necessary to prevent parasitic infection in their domestic animals