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Fault detection and classification (FDAC) for islanded power networks is a challenge due to low short circuit current fed by inverter interfaced distributed generator (IIDGs), control dependent fault models and bi-directional current flow. This article proposes a FDAC scheme, which utilizes the local voltages, measured at relay terminals. The transient monitoring function (TMF) of the voltage signal ($T_{v}$) gives the information of the fault transients. The proposed scheme is validated on the modified CIGRE test microgrid and IEEE 33 bus distribution network. Several test cases are simulated in MATLAB/Simulink at various locations with different inception angles, loading conditions, and fault resistances. The obtained results proves the accuracy of proposed FDAC scheme, with local information available at relaying points. The relays can be programmed to adapt to the proposed scheme, and hence there is no need for additional communication. Experimental validation with Texas Instruments digital signal controller (DSC) TMS320F28377D and OPAL-RT real time digital simulator shows the efficacy of the proposed scheme for practical implementation. Further, performance during no-fault scenarios, and accuracy with different controllers and current limiting algorithms are also illustrated.

The replacement of fishmeal (FM) with economical and nutritious FM alternatives including plant- and animal-based protein ingredients has become a global research priority. However, the presence of several anti-nutritional factors (ANFs) in these alternatives may impair nutrient utilization in fish. The supplementation of exogenous protease as feed additives could be an effective approach to improve the nutrient digestibility of these alternative proteins. Proteases are protein-digesting enzymes that catalyze the hydrolysis of complex protein macromolecules into simpler amino acids. Exogenous protease supplementation stimulates the activities of endogenous proteolytic enzymes for better nutrient digestion and absorption in fish. This review article summarizes the optimum protease supplementation levels in various fish species and its beneficial effects on growth performance, nutrient digestibility, intestinal morphology, digestive enzyme activities, whole-body composition, physiochemical parameters, immunity, and gene expression of fish. Moreover, the interactive effects of exogenous protease with organic acids and probiotics are also discussed. Overall, the supplementation of exogenous protease in fish feed is a viable solution for poor nutrient utilization of FM alternatives. Important gaps, however, exist in the current knowledge, particularly with regard to the effect of protease supplementation in animal-based proteins as most of the studies have focused on the effect of protease supplementation on plant-based proteins as FM alternatives. Moreover, additional studies focused on the effect of protease supplementation on the digestive enzyme activities, immunity, gut microbes and antioxidant parameters of fish will provide the basis for a better understanding of the mode of action of protease. The scarce knowledge in these areas limits the scope of protease supplementation as a feed additive in the aquaculture sector.

Out-of-system (OoS) interference is a potential limitation for distributed networks that operate in unlicensed spectrum or in a spectrum sharing scenario. The OoS interference differs from the in-system interference in that OoS signals and their associated channels (or even their statistics) are completely unknown. In this letter, we propose a novel distributed algorithm that can mitigate OoS interference in the uplink and suppress the signal transmission in the OoS direction in the downlink. To estimate the OoS interference, each access point (AP), upon receiving an estimate of OoS interference from a previous AP, computes a better estimate of OoS interference by rotate-and-average using Procrustes method and forwards the estimates to the next AP. This process continues until the central processing unit (CPU) receives the final estimate. Our method has comparable performance to that of a fully centralized interference rejection combining algorithm and has much lower fronthaul load requirements.

Seeking to reduce the computational effort to model the intrinsically complex active distribution networks (ADNs), this article proposes a new realistic approach to develop a real-time reduced steady-state model of an ADN using synchrophasor measurements. Such models facilitate much needed co-simulation of the bulk power system (BPS) and multiple ADNs for grid support applications. With the advent of distribution-level phasor measurement units (D-PMUs), the synchrophasor data are employed to derive the reduced model parameters in real-time and track the time-varying ADN operating point. The proposed approach develops a general three-phase four-wire reduced model which can replace any arbitrary feeder configuration confined within D-PMUs. The explicit modelling of neutral-wire under different neutral-grounding conditions results in accurate representation of any unbalanced and complex feeder segment, containing transformers, distributed generators, loads and n-phase laterals. Further, the reduced model is modified to account for embedded distributed generation, which is useful for effective estimation of grid support capability at the transmission-distribution interface. The proposed reduced model has been extensively validated on the highly unbalanced IEEE-13 bus feeder system for various test cases, including high penetration of locally-controlled photovoltaic inverters. DIgSILENT PowerFactory MATLAB co-simulation has been used as the platform to establish the model accuracy.

Accurate estimation of non-synchronous inertia in renewable energy (RE)-integrated power systems is challenging through conventional approaches, as emulated inertia from inverter-based resources (IBRs) is fundamentally different from the inherent inertial response of synchronous generators. In this context, this paper presents a novel realistic approach for estimating the non-synchronous inertial response in a large-scale RE-integrated power system. The method incorporates an optimal number of frequency and voltage monitoring nodes while ensuring an accurate estimation of non-synchronous inertia. In the proposed method, the synchronous inertial response for a frequency disturbance is estimated first using the conventional approach, followed by an estimate of the loads’ inertial contribution. The latter is calculated using center-of-inertia frequency and voltage measurement across the power system with a voltage-controlled zone approach. Finally, the non-synchronous inertial response is estimated by segregating the aggregate inertial response of synchronous generators and the loads from the overall estimated inertia of the system. The proposed approach can help the system operator determine inertial contributions from the loads and IBRs depending on loading conditions and the availability of virtual inertia from RE sources, estimate the minimum required synchronous inertia, and select the appropriate proportional gains and time constants of virtual inertial controllers. The proposed method is validated by implementing it on a modified IEEE 39-bus system and a real-life Gujarat State grid model (in India).

Grid integration of large-scale power electronic interfaced renewable energy sources leads to a low inertia system, thus resulting in a high rate of change of frequency (RoCoF) and frequency deviations in the power system following a credible contingency. In this article, a realistic adaptive communication-independent control strategy for effective inertial and primary frequency support from multiterminal HVDC (MTDC) connected offshore wind farms (OWFs) has been proposed. The proposed strategy can identify and distinguish the grid under disturbance among the other healthy grids in the MTDC system by an adaptive droop frequency support (ADFS) scheme at each receiving end converter (REC). On the OWF side, the control system of wind turbine generators has been designed to coordinate with the ADFS scheme to comply with the grid code regulations (GCRs) for inertial and primary frequency support. The proposed ADFS control scheme ensures that while providing frequency support to the grid under disturbance, frequency deviation limits of the healthy neighboring grids are not breached. Moreover, the proposed strategy complies adequately with the maximum permissible limits of HVDC voltage deviation. Furthermore, the proposed strategy is dependent on only local measurements and can be easily customized to comply with any applicable GCR. The reliability and effectiveness of the proposed robust control strategy have been demonstrated on three power systems interconnected through the MTDC system to two OWFs.

Wheat powdery mildew possesses a significant threat to wheat crops not only on a global scale but also in the northern region of Pakistan. Recognizing the need for effective measures, the exploration and utilization of exotic germplasm take on critical importance. To address this, a series of trials were made to investigate the response of 30 European (EU) lines, in addition to the local checks (Siran, Atta-Habib (AH) and Ghanimat-e-IBGE) against wheat powdery mildew at the Himalayan region of Pakistan. The study involved field testing from 2018 to 2022 across multiple locations, resulting in 38 different environments (location × year). In addition to field evaluations, molecular genotyping was also performed. The disease was absent on the tested lines during 2018, 2019, and 2020 whereas it ranged from 0 to 100% at Chitral location during 2021, where 100% was observed only for one EU wheat line “Matrix.” The disease prevailed only at Gilgit location (0–60% for EU wheat line “F236”) and at Nagar location (0–10% for EU wheat lines Substance and Nelson) during the disease season of 2022. Most of the EU wheat lines showed very low ACI values, due to an overall low disease pressure. Matrix showed the maximum ACI (1.54) followed by Ritter (1.25) and Bli_autrichion (0.87), whereas the minimum (0.1) was for Substance, JB_Asano, and KWS_Loft followed by Canon (0.19), all exhibiting partial resistance. The molecular marker-based screening revealed that Pm38was the most prevalent and detected in 100% of wheat lines followed by Pm39(60%) and Pm8(30%). Six wheat lines (20%) possessed all three Pmgenes (Pm8, Pm38, and Pm39) concurrently. The variability observed in this study can be utilized in future breeding efforts aimed at developing resistant wheat varieties.

•Examine the potential role of MaaS as a transport demand management (TDM) tool.•Conduct a stated choice experiment among employees in the Netherlands.•Show that MaaS could be a promising TDM when combining carrots (low MaaS package prices) and sticks (parking price increases).•Examine the behavioral change potential per user category.

ABSTRACTWheat yellow/stripe rust pathogen Puccinia striiformisis highly diverse and recombinant in the north of Pakistan in the Himalayan region. However, little is known about the role of this diversity in disease epidemics in areas where wheat yellow rust is an important disease in both irrigated and rain-fed wheat (i.e., in the plains of Pakistan). We explored the population diversity in P. striiformisduring the rust epidemics of 2013 in the major wheat-growing regions of Pakistan (the Himalayan region, central Khyber Pakhtunkhwa [KP], southern KP, central and northern Punjab). Disease severities among commonly grown cultivars ranged from 5% to 100%. Microsatellite genotyping with 16 simple sequence repeat (SSR) markers revealed a high diversity among 266 isolates collected during the season, with the Simpson diversity index (Simpson 1949) ranging from 0.870 (Himalayan) to 0.955 (southern KP). The recombination signature was stronger in the Himalayan population and central KP compared with wheat-growing regions of Punjab and southern KP. The overall diversity was higher in Pakistan relative to the clonal populations present in Europe, Australia, and the Americas. Analyses of population subdivision revealed no clear evidence of spatial structure for samples from Pakistan, with a maximum fixation index (FST) value of only 0.10. The lack of clear population subdivision could be attributed to migration of pathogen. In turn, the high diversity of P. striiformisin Pakistan represents a potential threat to wheat production in the region and worldwide, as a possible source to found clonal populations in diverse wheat-growing areas.

This paper presents a bi-level planning approach to find an optimal layout for a large-scale wind farm (WF) from economic and reliability perspectives. The upper level of the planning approach is formulated as constrained multi-objective optimization (MOO) to obtain the optimal WF layout, where two conflicting objectives are optimized simultaneously. Two objectives for MOO are i) yearly gross energy production and ii) annual loan repayment (for cable and land area of the WF), where the first objective is maximized and the second objective is minimized. Jensen's wake model is used to calculate the wake effect, and to evaluate the multiple wake effect within a WF, a coordinate-transformation-based approach has been adopted in this study. An efficient hybrid multi-objective metaheuristic algorithm, which is based on nondominated sorting multi-objective particle swarm optimization and improved archive multi-objective simulated annealing, has been proposed to find the optimized WF layout. The superiority of the Pareto front obtained by the proposed algorithm for the large-scale WF layout is supported by its comparison with different powerful and well-established MOO algorithms. In the lower level of the proposed approach, economic and reliability analyses of the solutions (WF layout), obtained in the Pareto front by the proposed hybrid algorithm, have been done. In this context, two performance metrics, a) generation economy index and b) expected wind energy generation (EWEG), have been considered. A sequential Monte Carlo simulation has been developed to calculate the EWEG considering random failure of both wind turbines and cables in this paper. The most suitable WF layout is selected by trading off between economy and reliability using a fuzzy decision-making approach.

ABSTRACTThe present study was designed to estimate the zinc (Zn) requirement of Labeo rohitajuveniles fed practical diet. Treatments used for the study were consisted of six experimental diets supplemented with graded levels of Zn (0, 21, 42, 63, 84 and 104 mg/kg diet) from Zn gluconate. For each experimental diet, two replicates were allocated, and 18 fish were stocked in each replicate. The feeding trial was lasted for 90 days. Results showed that final weight, absolute weight gain, weight gain% and specific growth rate increased with increasing dietary Zn levels up to 42 mg/kg and started to decrease with further increase in dietary Zn level. Quadratic regression analysis of weight gain% data indicated that L. rohitajuveniles required 62.58 mg/kg Zn for normal growth. Maximum Zn absorption was observed in fish fed diet supplemented with 42 mg/kg Zn compared with other dietary treatments. Alkaline Phosphatase (ALP) activity in kidney and spleen of L. rohitajuveniles increased with the increase in dietary Zn levels up to 42 and 63 mg/kg, respectively. Conclusively, supplementation of graded levels of dietary Zn-gluconate improved the growth performance and increased the Zn bioavailability and ALP activity up to a certain limit in L. rohitajuveniles.

ABSTRACTThe present research work was conducted to investigate the effects of microbial phytase and citric acid supplementations on nutrient digestibility performance by rohu (Labeo rohita) juveniles fed a sunflower meal (SFM)-based diet. The basal diet was supplemented with two levels of phytase (0 and 1000 FTU/kg) and each level of this phytase-supplemented diet was further supplemented with two levels of citric acid (0% and 2%). Chromic oxide (1%), as an inert marker, was added to the diet to determine nutrient digestibility. Results showed that digestibility of dry matter, crude protein and ether extract was significantly (p < .05) enhanced by citric acid supplementation. Similarly, phytase pretreatment also resulted in improved (p <.05) digestibility of dry matter, crude protein and ether extract. Also, citric acid and phytase supplementation improved (p < .05) the digestibility of P, Na, K, Ca, Mg, Cu, Zn, Mn and Fe. Nevertheless, the addition of both supplements (citric acid and phytase) simultaneously did not produce any interaction for the digestibility of these minerals. Hence, it is concluded that phytase (1000 FTU/kg) and citric acid (2%) supplementation to an SFM meal-based diet improved the nutrient digestibility in L. rohitajuveniles.

ABSTRACTThe present feeding trial was conducted to assess the optimal level of phytase supplementation required for maximum nutrient absorption and growth performance of Labeo rohitafingerlings fed canola meal-based diet. A standard diet having 30.21% protein and an energy value of 4.26 kcalg−1was used as reference diet. The experimental diet having similar protein and caloric density was formulated by using 70% reference diet and 30% of canola meal as test ingredient. This experimental diet was then divided into seven test diets and were supplemented by graded levels (0, 250, 500, 750, 1000, 1250 and 1500 FTU kg−1) of phytase enzyme. Chromic oxide was used in reference and test diets as an inert marker. Results showed that phytase supplementation at 750 FTU kg−1level effectively increased apparent digestibility coefficients of crude protein (64%), crude fat (76%) and gross energy (68%) as compared to reference and other phytase-supplemented diets. The results of present study showed increased growth and feed performance of fingerlings in response to phytase supplementation. Maximum performance was obtained by the fish fed on test diet having 750 FTU kg−1level. It was concluded that 750 FTU kg−1level of phytase supplementation in canola meal-based diet is sufficient for increasing nutrient digestibility and growth performance of L. rohitafingerlings.

Pakistan's planners, realizing that energy conservation is actually the cheapest, readily available and environment-friendly source of energy supply, created the National Energy Conservation Centre (ENERCON) in 1986 to plan, demonstrate [...]

The current study aimed to assess the effects of various selenium(Se) sources on the growth performance, blood biochemistry, and antioxidant status of intensively reared silver carp. For this, (N = 420) fingerlings with an average body weight of 13 ± 1.5 g were randomized into 21 aquariums (20 fish/100 L aquaria) and was subjected to one of the seven dietary treatments under completely randomized design. The dietary treatments were control(C), with 0.5 mg/kg sodium selenite(N-0.5), 1 mg/kg sodium selenite(N-1), 0.5 mg/kg Se methionine(M-0.5), 1 mg/kg Se methionine(M-1), 0.5 mg/kg Se yeast(Y-0.5), and 1 mg/kg Se yeast(Y-1). The experiment was of two-weeks of fish acclimatization to ponds followed by 12-weeks of feeding trial. The source of Se influenced the growth performance and the group M-0.5supplemented diet achieved the highest(P < 0.05) final body weight (BW), final length, BW gain, and specific growth rate than others. The selenium concentration of liver, kidney, and muscle was significantly higher(P < 0.05) in methionine fed groups compared to others. However, concentrations of Se in liver, kidney and muscle were similar (P > 0.05) in fish supplemented with M-0.5 and M-1. The dry matter, fat, ash and protein contents of the fish meat were similar (P > 0.05) in all. The WBCs, HGB, HCT, and MCHC were higher (P < 0.05) in the M-0.5 supplemented group than the rest of the treatment groups. Similarly, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were also higher (P < 0.05) in the M-0.5 supplemented group compared with others. However, TBARS for liver and serum were not influenced (P > 0.05) by Se supplementation. Similarly, levels of superoxide dismutase, catalase, and peroxidase enzymes in the fish whole body, muscle, and liver were also remained unchanged (P > 0.05). From the findings, we can conclude that Se methionine is the best source, and 0.5 mg/kg dietary supplementation improved the growth performance, organs enrichment, and antioxidant status of silver carp.

The bottleneck travelling salesman problem is to find a Hamiltonian circuit that minimises the maximum arc length in a graph. We first modify an existing lexisearch algorithm by incorporating good upper and lower bounds to obtain exact optimal solution to the problem. Then we present a data-guided lexisearch algorithm. Depending on the medians of rows of the cost matrix for the problem, the nodes of the network are renamed and a new alphabet table is constructed and then the modified lexisearch algorithm is applied. It is shown that this minor preprocessing of the data, before the lexisearch algorithm is applied, improves computational time substantially. The efficiency of our algorithms as against the existing lexisearch algorithm to the problem has been examined for some TSPLIB (1995) instances and a variety of randomly generated instances of different sizes and different types.

Crossover operator plays a vital role in genetic algorithms. This paper proposes the multi-parent sequential constructive crossover (MPSCX), which generalises the two-parent sequential constructive crossover (SCX) to a multi-parent crossover for the travelling salesman problem (TSP). Experimental results on five TSPLIB instances show that MPSCX significantly improves SCX by up to 4.60% in average tour value with maximum 4.01% away from the exact optimal solution. Finally, the efficiency of the MPSCX is compared as against multi-parent partially mapped crossover (MPPMX). Experimental results show that the MPSCX is better than the MPPMX.

OBJECTIVE: To describe a case of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) associated with lisinopril therapy.CASE SUMMARY: A 76-year-old white woman who was being treated with lisinopril and metoprolol for hypertension presented with headaches accompanied by nausea and a tingling sensation in her arms. Her serum sodium was 109 mEq/L, with a serum osmolality of 225 mOsm/kg, urine osmolality of 414 mOsm/kg, and spot urine sodium of 122 mEq/L. Diclofenac 75 mg qd for osteoarthritic pain and lisinopril 10 mg qd for hypertension was begun in 1990. Lisinopril was increased to 20 mg qd in August 1994 and to 20 mg bid prn in August 1996 for increasing blood pressure; metoprolol 50 mg qd was added in July 1996. A diagnosis of SIADH was postulated and further evaluation was undertaken to exclude thyroid and adrenal causes. After lisinopril was discontinued and the patient restricted to 1000 mL/d of fluid, serum sodium gradually corrected to 143 mEq/L. The patient was discharged taking metoprolol alone for her hypertension; serum sodium has remained ≥138 mEq/L through April 1999, 32 months after discharge, despite daily use of diclofenac.DISCUSSION: Angiotensin-converting enzyme (ACE) inhibitors in antihypertensive doses may block conversion of angiotensin I to angiotensin II in the peripheral circulation, but not in the brain. Increased circulating angiotensin I enters the brain and is converted to angiotensin II, which may stimulate thirst and release of antidiuretic hormone from the hypothalamus, eventually leading to hyponatremia.CONCLUSIONS: SIADH should be considered a rare, but possible, complication of therapy with lisinopril and other ACE inhibitors.

•Techno-economic feasibility analysis is done for hybrid offshore wind-solar pv plant.•PSO is used for layout optimization to maximize the generation output.•LCOE of the hybrid offshore plant is better compared to the OWF for the Gujarat site.•Using the existing infrastructure of OWF to set up hybrid plant is more beneficial.•LCOE for the aforementioned case reduces by 8.25% compared to the new hybrid plant.

Recent research has shown that carbon nanotube (CNT) acts as a model reinforcement material for fabricating nanocomposites. The addition of CNT as a reinforcing material into the matrix improves the mechanical, thermal, tribological, and electrical properties. In this research paper multiwalled carbon nanotube (MWCNT), with different weight percentage (5%, 10%, and 15%), was reinforced into manganese dioxide (MnO2) matrix using solution method. The different weight % of MWCNT/MnO2 nanocomposite powders was compacted and then sintered. The phase analysis, morphology, and chemical composition of the nanocomposites were examined by X-ray diffractometer, Field Emission Scanning Electron Microscope (FESEM), and Energy Dispersive X-Ray (EDX), respectively. The XRD analysis indicates the formation of MWCNT/MnO2 nanocomposites. The FESEM surface morphology analysis shows that MnO2 nanotube is densely grown on the surface of MWCNT. Further, microhardness of MWCNT/MnO2 nanocomposite was measured and it was found that 10 wt% has higher microhardness in comparison to 5 and 15 wt%. The microhardness of the composites is influenced by mass density, nanotube weight fraction, arrangement of tubes, and dispersion of MWCNT in H2SO4(aq) solution.