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This review paper is the knowledgeable journey of nutrition in which we get to know how Spirulina help us to fight with cancer, improve our immune system, give healthy heart, and save us from viruses. And we will also know that how it comes in our dietary process. And this review paper will make us familiar to use Spirulina as a supplement. Spirulina, is the simplest plant algae if we talk about its structure then we found that complex composition of this plant is packed in simple structure. Research says that Spirulina has been a common dietary substance (food) around the world from ancient times. Because of no strong scientific evidence of Spirulina it was not so popular for its nutritive and health benefits. For the recent years, Spirulina has attracted scientific attention when NASA has published research paper, and show the whole world get to know about the unlimited nutrition package just in a single spoon, and safe functional food. Commercially we can produce large outdoor ponds under controlled conditions and harvesting easily. In this paper we will get to know about the richness of vitamins and minerals in Spirulina. We will also get to know how we can cultivate it and what are the requirements of this plant to get a good yield of our crop? We have shown some real photographs of cultivation of this plant on a large scale in Tamilnadu. [ABSTRACT FROM AUTHOR]

The Climate change is the most pressing issue confronting Humanity lack of effective prediction techniques resulting in the damage of infrastructures and resources, collective climate predictions mechanism will not help the mankind we need a selective or personalized prediction techniques which can be more beneficial in predicting the climate changes closely. Natural catastrophes, Temperature analysis is the most essential areas where a personalized prediction techniques plays vital role. Here we are focusing in climate prediction at farms by forecasting solar radiation which climate changes are directly dependent on by using meteorological conditions such as temperature, radiation, pressure, humidity, wind speeds using Machine learning to anticipate the climatic change in advance helps farmers in analyzing natural risks that arise as a result of abrupt climate change. Farmers may use the predictions to schedule seed sowing and pre harvesting according to predictions in safeguarding crop. [ABSTRACT FROM AUTHOR]

In statistics, mean is one of parameter estimators. The difference of mean calculation method will give different result, which finally can influence the value of estimation. In this paper, the comparison of two mean calculation ways, uniform-weight and non-uniform-weight, is discussed. The methods will be explained in this paper are common mean calculation (uniform-weight), weighted mean calculation based on data position in bloxplot and weighted mean calculation using fuzzy logic (non-uniform-weight). To examine the methods, the harvest of plantation is employed. The result shows that mean calculation with non-uniform-weight gives parameter estimator with small error. [ABSTRACT FROM AUTHOR]

The paper presents the kinematics of the satellite (roller) interacting with the flexible links of the epi and the hypocyclic planetary mechanism to drive the spindles of the vertical spindle cotton picker apparatus. When calculating the movement of the spindles in the harvesting device, the geometric sliding of the drive rollers along flexible belt drives was taken into account due to the small value of their wrap angle. The cyclogram of a bicyclic planetary gear for the drive of the spindles is given. The graph of the curve of the epicyclic, hypocyclic trajectory of movement of the satellite point and the character of the movement of the trajectory of the point of the satellite curve of the planetary mechanism in the working, removable, and transition zones are presented. [ABSTRACT FROM AUTHOR]

Discrete Element Method (DEM) has found practical application in simulations of processes in many braches of science and technology, among others in biosystems engineering. Agriculture and food engineering harvests, stores, handles or processes an enormous amount of particulate material of biological origin. The paper presents short review of application of DEM to model the representative unit operations of soil tillage, crop harvesting, and post-harvest processing of agricultural materials. [ABSTRACT FROM AUTHOR]

The pursuit of novel sources of food, especially functional food ingredients, has been intensively carried out to accommodate the urges of double burden malnutrition countermeasures in Indonesia. One potential bioresource to be locally utilized is microalgae due to its plentiful nutritional properties and nutraceutical value. Numerous explorations have been done in isolating microalgae from multiple regions in Indonesia and observing their nutrition and nutraceutical character. Furthermore, the use of microalgae in various functional food products also has been studied. However, the use of Indonesian microalgae as food is still limited. The quite complicated isolation process, as well as a, must be well-controlled culture and harvesting processes are the main difficulties. Hence, the purpose of this paper is to examine the cultural process and prospects of microalgae as functional food ingredients from nutritional and nutraceutical aspects in Indonesia. This information can be used for further exploration of Indonesia-origin microalgae-based sources of food. Moreover, this information can also be beneficial for further development in applying microalgae in a lot of functional food products. [ABSTRACT FROM AUTHOR]

Piezoelectric energy harvester system has fascinated rigorous consideration in the area of self powered wireless sensor networks. A complete piezoelectric energy harvesting system constitutes three basic components namely, piezoelectric device, interfacing circuits and storage element. In this paper, a simulation study has been carried out on coupled modeling between piezoelectric device and other interfacing circuits. It has been observed that approximately 99 μW, 83 μW and 30 μW maximum power across 100kΩ optimum load resistance has been obtained from P-SSHI, S-SSHI and SECE interfacing circuits, respectively. Therefore, it can be stated that coupled modeling with self powered P-SSHI circuit performed better as compared to S-SSHI and SECE circuits. [ABSTRACT FROM AUTHOR]

This paper deals with the power production from a piezoelectric biodynamic harvesting scheme via the local step optimization point of the algorithm. In addition, the sensitivity and error of the maximum power point tracking (MPPT) algorithm are determined in this work due to its non-linear extrapolation approach in order to provide a real-time adaptation of the circuit impulses and to obtain matching of the target load impedance. The presented method provides a non-linear extrapolation model for the combined harvester design based on an artificial neural network (ANN). An analytical model of harvestable electrical power for piezoelectric vibration energy generation is proposed. Furthermore, steering stability is enhanced by a strong active front steering and an active differential drive control. The applicability of this approach outperformed the conventional method of observing perturbations under various operational requirements. [ABSTRACT FROM AUTHOR]

Harvesting policy is an important issue in maintaining the existence of a population. This paper is focused on studying the effects of continuous predator threshold harvesting policy on the dynamical behavior of a fractional-order Gause-type predator-prey system. This policy is applied to ensure that harvesting does not occur when the population density is less than a specified threshold. The dynamical analysis is done to study the local stability of equilibrium points and the existence of Hopf bifurcation. By using a fractional-order predictor-corrector method, the numerical results are shown to illustrate the analytical result. [ABSTRACT FROM AUTHOR]

In the present paper, a predator-prey model with holling type IV functional response in the presence of weak Allee effect and non-linear harvesting in prey species has been proposed and analyzed. The local stability, existence of a Hopf bifurcation, direction of Hopf-bifurcation and the stability of the bifurcating periodic solution at the positive interior equilibrium point for the temporal model has been studied. The stability of positive constant equilibrium, Hopf-bifurcations, and diffusion-driven Turing instability for the spatio-temporal model under the Neumann boundary conditions has also been analyzed. Numerical simulations have been carried out to validate the analytical findings. [ABSTRACT FROM AUTHOR]

Powering of remotely placed sensors or health monitoring devices for bridges, large buildings or aircrafts, are more difficult. Here comes the need of an energy harvesting system that can scavenge energy from the vibrations produced by the wind or vibrations from the surroundings. Piezoelectric Energy Harvesting System (PEHS) is found suitable for these applications, since it is capable of converting the mechanical vibrations or pressure variations into electrical output. Piezoelectric materials are preferred due to the attractive features like high energy density, compactness and light weight. They are most suitable for powering Structural Health Monitoring (SHM) sensors of aircraft structures, bridges, buildings etc. For optimizing the PEHS, understanding and characterization of the sources of vibration/ stress and the displacement are helpful. Introduction of interdigitated electrodes in the PEHS ensure the uni form electric field along the piezoelectric fiber material and hence, enhance the actuation. This is really good news for the electronic designers that, the energy harvested from the Interdigitated PEHS can be used for providing power to many remote applications like structural health monitoring, wireless sensors and other such requirements. [ABSTRACT FROM AUTHOR]

In this paper, we deal with a predator-prey system with harvesting term and Holling-II type functional response under Dirichlet boundary condition. Firstly, we give a prior estimate by using the Maximal Principle and the upper and lower solution method. Secondly, we investigate the existence of local bifurcation of semi-trivial solution by applying the spectrum analysis method and bifurcation theory. Finally, we show that the local bifurcation can be extended to global bifurcation, and the continuum goes to infinity. [ABSTRACT FROM AUTHOR]

Outbreaks of spruce budworm are natural and common disturbance in the forest of North America and Canada. The large population of spruce budworm can cause significant change in the fir trees. Several strategies have been used to reduce the spruce budworm population. In this paper, we use constant yield harvesting techniques to reduce the spruce budworm population and develop new mathematical models. [ABSTRACT FROM AUTHOR]

Harvesting microalgae is challenging due to the nature of microalgae having very small size, about similar density to water, and high membrane fouling propensity. Numerous techniques have been implemented for membrane fouling control including periodical cleanings, optimizing operational conditions and imposing shear-rates, such as using air bubbles. Nevertheless, air bubbles effectiveness can still be further improved by maximizing the shear-rates impact to scour foulant on membrane surface. In this paper, a new method to enhance membrane cleaning effect of air bubbles is presented. It was done by tilting the module to maximize contacts of air bubbles on the membrane surface. First of all, we investigate the effect of tilting angle, followed by the effect of switching period, and lastly the effect of aeration rate. The tests were conducted in a lab-scale submerged filtration treating microalgae broth solution. The filtration performance was judged based on steady state permeability. The results showed that increasing tilting lead to further improvement the cleaning efficiency by offering higher permeability. It was also identified that operating at one-sided membrane under optimum tilting angle matches permeability of a two-sided membrane at the same tilting angle, in which the later involved switching mode. Higher aeration rates lead to higher permeability and tilting membrane at 15° can reduce up to 30% of specific aeration demand, and thus improves energy saving. This tilted membrane module can lead to significant cost reduction as well as offers energy saving for membrane fouling control. [ABSTRACT FROM AUTHOR]

Pressure driven membrane processes have been proven suitable for the separation of microorganisms in many of biotechnical applications. In this paper, we report the preparation and characterization of a novel nylon 6, 6 nanofibers membranes and applied it for filtration of Chlorella vulgaris broth. Its performance is compared with a phase inverted polyvinylidene fluoride (PVDF) membrane, an established membrane material for this application. The tests on the filterability of both membranes and their harvesting efficiency were conducted. Results show that nanofiber membrane is more hydrophilic (contact angle of zero), and has 45% higher surface pore size and 20% surface pore population that contribute significantly into its higher clean water permeability (of 1018 and 493 l/m2hbar for nanofiber and PVDF membranes respectively). Filterability results show that nanofiber membrane has superior advantages over the phase inverted one: 2-5 times higher in productivity while maintaining similar rejection of 92%. Those results were consistent for three independent filterability tests. This finding confirms the potential application of nanofiber membrane. However, further development with respect to improving its mechanical strength and its ability to be assembled into a membrane module should be critical to serve its promise in this particular application. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a prey-predator model where the susceptible prey becomes infective. We consider the case where the predator will consume the unhealthy prey and at the same time the healthy prey will be harvested. Conditions for the stability of the equilibrium points were obtained. We show when the disease rate is increasing, the trajectories of the general model approach the equilibrium in which all population survive. Also we show that the threshold of harvesting is important because when it approach the size of prey this make the disease increasing so we must start the harvesting so early to control the disease and not become epidemic. [ABSTRACT FROM AUTHOR]

Converting waste into resources has been rolled out all over the world to solve environmental problems and also can generate economic potential. The processing of organic waste, as a majority of domestic waste, into products with an economic value has also been widely developed, one of which is the BSF maggot bioconversion method. It can not only produce compost but also maggot which has a high protein content for livestock and fisheries. In this case, the practice of processing organic waste using maggot was applied at the Az-Zakaria Islamic Boarding School in Sindangbarang Village, Jalaksana District, Kuningan Regency, West Java. The process carried out is: organic waste collected from kitchen activity and pre-treatment is carried out by chopping it, then putting it into a tub containing maggot larvae. Periodically the maggotis harvested as well as the resulting compost is harvested. 30% of the maggot larvae are then bred, and 70% are harvested eitherto be used as feed for catfish, chickens, or direct sale. Meanwhile, the compost produced is used for organic vegetable plants. The economic results of this activity can help students and their families for alternative post-pandemic businesses. [ABSTRACT FROM AUTHOR]

Dried red chile peppers [Capsicum annuum (L.)] are an important agricultural product grown throughout the Southwestern United States and is extensively used in food and for commercial application. Given the high, broad demand for chile attention to the methods of harvesting, storage, transport, and packaging are critical for profitability. Currently, chile should be stored no more than 24 to 36 hours at ambient temperatures from the time of harvest due to the potential for natural fermentation to destroy the crop. The rate for calculating and determining the amount of useable/destroyed chile in ambient conditions is determined by several variables that include the harvesting method (hand-picked, mechanized), time of harvest following the optimal harvesting point (season), weather variations (moisture). In this work, a stochastic simulation-based model is presented to forecast optimal harvesting scenarios capable of supporting farmers and chile processors better plan/manage planting and growth acceleration programs. The tool developed allows for the economic feasibility of storage/stabilization systems, advanced mechanical harvesters, and other future advances based on the amount increase in chile yield to be analyzed. We used described simulation as an analysis tool to obtain the expected coverage and the estimation of the mean and quantile. [ABSTRACT FROM AUTHOR]

The output power of the PV system fluctuates due to the instability of weather conditions, unstable environment, and weather changes. Furthermore, solar irradiance can change suddenly because the sunlight is blocked by obstacles such as a moving cloud, the shadow of a building or tree, and atmospheric conditions. These factors cause an instantaneous change in the peak power. The peak power can vary into multi-peak points with different values, and such a condition is known as partial shading. This work report delivers the improving effort to harvest electrical energy taken from PV systems under partial shading conditions (PSC). By combining two algorithms, namely Simplified Firefly Algorithm (SFA) under multi-peak conditions and the perturb and observe (P&O) for maximum power point tracking (MPPT). The work is carried out using different PV configurations, varying shading patterns, and multi-peak conditions in partial shading conditions. The simulation results have shown satisfactory performance to avoid local maximum power peak and better accuracy in tracking global maximum power peak (GMPP) during partial shading. The maximum electric yield harvested in this work is 363,93 Watt. [ABSTRACT FROM AUTHOR]

A predator-prey model with proportional prey harvesting and square root functional response in prey has been studied. The existence and the local stability of equilibria of the system has been analyzed. By analysing the model it is observed that the dynamics of the model depends on the parameter values. It is examined the solutions near the interior equilibrium point the system exhibits Hopf bifurcation. The calculation of the Lypunov number shows that the Hopf bifurcation is super-critical. Various numerical simulations are carried out to justify the analytical results. [ABSTRACT FROM AUTHOR]

Allee effect and harvesting are two important objects in the ecological system since they are directly connected to the existence of biological resources. Here, we study the impact of the strong Allee effect in prey and Michaelis-Menten type of harvesting in predators on the dynamics of a Gause-type predator-prey model. To involve the influence of the memory effect, the Caputo fractional-order derivative is applied. As a preliminary analysis, we obtain three types of equilibrium points namely the origin point, a pair of the predator extinction points, and the co-existence point. Some interesting dynamics are shown such as the local stability for each equilibrium point, the existence of transcritical bifurcation around the predator extinction points, and the occurrence of Hopf bifurcation around the co-existence point. Furthermore, some numerical simulations are performed to reinforce the theoretical findings. [ABSTRACT FROM AUTHOR]

A modified Leslie–Gower predator–prey model with stage–structure and Michaelis–Menten type harvesting in prey is proposed and studied in this work. Here, the population is divided into three sub–populations namely immature prey and mature prey as well as predator. We assume that the predator only consumes immature prey. In addition, the harvesting process only considered in the immature prey population. We investigated the existence of all possible equilibrium states of the system and discuss the stability of equilibrium state. The results has been shown that by the change of parameters, all population could eventually coexist, become extinct, or predator population will be driven to extinction and the prey population will coexist, or else the prey to extinction and the predator will exist. Furthermore, the harvesting process in the immature prey have an impact on the dynamical behaviour of system. Numerical simulations are presented to confirm the analytical results. [ABSTRACT FROM AUTHOR]

Biomass is an important renewable source of energy. Residues that are obtained from harvesting and agricultural products can be utilised as fuel for energy generation by conducting any thermal energy conversion technology. The conversion of biomass to bio oil is one of the prospective alternative energy resources. Therefore, in this study fast pyrolysis of oil palm shell was conducted. The main objective of this study was to find the optimum condition for high yield bio-oil production. The experiment was conducted using fixed-bed fluidizing pyrolysis system. The biomass sample was pyrolysed at variation temperature of 450°C - 650°C and at variation residence time of 0.9s - 1.35s. The results obtained were further discussed in this paper. The basic characteristic of the biomass sample was also presented here. The experiment shows that the optimum bio-oil yield was obtained at temperature of 500°C at residence time 1.15s. [ABSTRACT FROM AUTHOR]

This paper deals with predator-prey interactions with predator harvesting and prey refuge. The predator may be infective by a disease. Therefore the predator is divided into two subclasses, i.e. infective and susceptible predator. It is assumed that susceptible predator have higher predation rate than infective predator, and hence the growth rate of susceptible predator will be higher than infective predator. It is found that the model has five equilibrium points. Finally, numerical simulation are presented not only to illustrate equilibrium point but also to illustrate effect of predation rate. [ABSTRACT FROM AUTHOR]

The vibrations of the mechanical system in resonance areas manifest both, the risk amplitudes of device response and the relatively high efficiency of energy harvesting. In laboratory conditions to keep the relatively high energy harvesting productivity, the assumed parameters of the shakers have to be secured. Unfortunately, the technical parameters of excitation source devices are restricted by their electrical and mechanical limitations. Hence in this work, the influence of the excitation in the rigid beam direction is analyzed for the composite beam response in the perpendicular flexible direction. We modeled the beams with determined sets of composite layers, and simulated the appeared effect of perpendicular vibrations to the excitation direction. Dissimilar dynamical behavior is observed while the configurations of the layers differ. We focused on the mechanical coupling of the sets of composite beam layers to get an optimal configuration. The energy harvesting is realized by the piezo element attached to the surface of the composite beam. [ABSTRACT FROM AUTHOR]

A discrete-time two-prey one-predator system with Holling Type-III functional response coupled with optimal harvest strategy is studied. The system represents the complex dynamics of two prey population, subjected to inter-species competition along with a constant harvesting effort and the predator population is exposed to intra-species competition. The conditions for existence and local stability of the fixed points are obtained, along with the sufficient conditions for permanent coexistence of the three species. [ABSTRACT FROM AUTHOR]

The North Eastern Region covers seven states of India and also called as ‘Land of the Seven Sisters’. North Eastern Region is bounded between North Latitudes 21° 57’ & 29° 28’ and East Longitudes 89° 40’ & 97° 25’ with the geographical area of 2.55 lakh sq.km [10]. Hill ranges occupy about 70% of the total geographical area. The region has two principal drainage systems viz. Brahmaputra and Meghna. North Eastern Region is characterized by tropical monsoon climate with a rainy summer and dry winter, with annual rainfall (mm) 1857.2, while in India is 1083.2 [6]. The availability of net ground water in NER is 40.35048 bcm [5]. Geological Formations encountered in the North Eastern Region range in age from Archaean to Recent. The major soil type of the NER is red loams, lateritic and soil of alluvium deposit. Water supply of North Eastern Region is dependent on both Surface and Ground Water. Based on the ground water occurrence and movement, hydrogeology of the region can be broadly grouped into a) Porous and b) Fissured formations. Water is one key input to agriculture for obtaining high yield for any crop. The popular irrigation system e.g. Gravity / Flow, Lift, Drip and Ground Water Irrigation in NER are directly depends on revival of traditional wisdom. Based on long experiences under existing soil and climatic conditions as well as availability of large number of springs, farmers in certain areas have developed typical systems of water management, which are very effective under the existing condition of topography and terrain. Some of these systems are bamboo drip irrigation in Meghalaya, Cheo-oziihi, Zabo in Nagaland, Apatani, Yetbung Linganag and Linkun in Arunachal Pradesh, Dongs, Dungs / Jampois in Assam etc. The study was done to analyses the effect of traditional system and culture associated with it for ground water management & revival of traditional wisdom in North Eastern Region. [ABSTRACT FROM AUTHOR]

An investigation of the nonlinear behavior of a bistable energy harvesting device is proposed by using a powerful analytical technique, namely the Optimal Homotopy Asymptotic Method (OHAM). This techni que proves its applicability in this kind of problems demonstrating a very fast convergence, due to the presence of the convergencecontrol parameters, whose optimal values, which are determined using rigorous procedure, ensure the convergence of the solutions after the first iteration. [ABSTRACT FROM AUTHOR]

In this research, we studied two species populations competing for a shared biotic resource in the environment with harvesting effects. Variable environmental carrying capacity represents the limited biotic resource available. Studies were done to investigate the effects of the enrichment parameter of the resource that sets the primary bifurcation parameter in the models. However, the models studied neglected the effects of population harvesting. Adding harvesting terms to the model would generate different kinds of dynamics in the system's behaviour. We investigated the steadystate solutions and their corresponding eigenvalues. The results can be displayed as bifurcation diagrams, which are useful in visualising the steady-state solution branches that exist in the system. [ABSTRACT FROM AUTHOR]

There are three species of jellyfish recorded in Sarawak which are the Lobonema smithii (white jellyfish), Rhopilema esculenta (red jellyfish) and Mastigias papua. This study focused on two particular species which are L.smithii and R.esculenta. This study was done to estimate the highest carrying capacity and the population growth rate of both species by using logistic growth model. The maximum sustainable yield for the harvesting of this species was also determined. The unknown parameters in the logistic model were estimated using center finite different method. As for the results, it was found that the carrying capacity for L.smithii and R.esculenta were 4594.9246456819 tons and 5855.9894242086 tons respectively. Whereas, the population growth rate for both L.smithii and R.esculenta were estimated at 2.1800463754 and 1.144864086 respectively. Hence, the estimated maximum sustainable yield for harvesting for L.smithii and R.esculenta were 2504.2872047638 tons and 1676.0779949431 tons per year. [ABSTRACT FROM AUTHOR]

In [1], a delayed three-species intraguild predation (IGP) model was considered. This particular tri-trophic community module includes a predator and its prey which share a common basal resource for their sustenance [3]. Here, it is assumed that in the absence of predation, the growth of the basal resource follows the delayed logistic equation. Without delay time, the IGP model in [1] reduces to the system considered in [7] where it was shown that IGP may induce chaos even if the functional responses are linear. Meanwhile, in [2] the delayed IGP model in [1] was generalized to include harvesting. Under the assumption that the basal resource has some economic value, a constant harvesting term on the basal resource was incorporated. However, both models in [1] and [2] use the delay time as the main parameter. In this research, we studied the delayed IGP model in [1] with the addition of linear harvesting term on each of the three species. The dynamical behavior of this system is examined using the harvesting rates as main parameter. In particular, we give conditions on the existence, stability, and bifurcations of equilibrium solutions of this system. This allows us to better understand the effects of harvesting in terms of the survival or extinction of one or more species in our system. Numerical simulations are carried out to illustrate our results. In fact, we show that the chaotic behavior in [7] unfolds when the harvesting rate parameter is varied. [ABSTRACT FROM AUTHOR]