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This article discusses the stability results for solution of a fractional q-integro-differential problem via integral conditions. Utilizing the Krasnoselskii’s, Banach fixed point theorems, we demonstrate existence and uniqueness results. Based on the results obtained, conditions are provided to ensure the generalized Ulam and Ulam–Hyers–Rassias stabilities of the original system. The results are illustrated by two examples.

Clay deposits typically exhibit significant degrees of heterogeneity and anisotropy in their strength and stiffness properties. Such non-monotonic responses can significantly impact the stability analysis and design of overlying shallow foundations. In this study, the undrained bearing capacity of shallow foundations resting on inhomogeneous and anisotropic clay layers subjected to oblique-eccentric combined loading is investigated through a comprehensive series of finite element limit analysis (FELA) based on the well-established lower-bound theorem and second-order cone programming (SOCP). The heterogeneity of normally consolidated (NC) clays is simulated by adopting a well-known general model of undrained shear strength increasing linearly with depth. In contrast, for overconsolidated (OC) clays, the variation of undrained shear strength with depth is considered to follow a bilinear trend. Furthermore, the inherent anisotropy is accounted for by adopting different values of undrained shear strength along different directions within the soil medium, employing an iterative-based algorithm. The results of numerical simulations are utilized to investigate the influences of natural soil heterogeneity and inherent anisotropy on the ultimate bearing capacity, failure envelope, and failure mechanism of shallow foundations subjected to the various combinations of vertical-horizontal (V-H) and vertical-moment (V-M) loads.

— In this paper, a single switch transformer-less DC-DC converter with continuous input current for photovoltaic applications is proposed. The suggested configuration utilizes a CL1C2D2 structure to achieve a high voltage gain and alleviate voltage pressure on the semiconductor components. This design enables a significant increase in voltage output with a minimal turns ratio, leading to reduced size, weight, and cost of the converter system. The reduction in turns ratio of the coupled inductor results in lowered voltage stress on the semiconductor elements. Additionally, employing just one power switch in the converter simplifies control and reduces expenses. With its continuous input current, this converter is particularly well-suited for integration in photovoltaic systems. Simulation results conducted using PSCAD/EMTDC software validate the efficacy of the proposed power converter. Furthermore, the maximum power output of the photovoltaic module through an MPPT (Maximum Power Point Tracking) controller under varying irradiance levels is determined, and simulations are executed using PSCAD/EMTDC.

The life table parameters and predation rate of Typhlodromus bagdasarjani Wainstein & Arutunjan (Phytoseiidae) fed on Cenopalpus irani Dosse (Tenuipalpidae) nymphs reared on four apple cultivars Kohanz Golab, Imperial Gala, Lebanon Red, and Granny Smith were determined under laboratory conditions. The longest developmental time of immature stages in females was observed on Kohanz Golab, and the shortest one was on Granny Smith. The fecundity ranged from 19.17 eggs/female on Golab Kohanz to 32.78 eggs/female on Granny Smith. The highest and lowest intrinsic rate of increase (r) were obtained on Granny Smith (0.251 day-1), and Kohanz Golab (0.113 day-1), respectively. The total prey consumption by all immature stages on Kohanz Golab, Imperial Gala, Lebanon Red, and Granny Smith was 42.90, 34.71, 31.83, and 24.53 prey, respectively. The total prey consumption by adult females was 543.76 prey on Kohanz Golab, 419.40 prey on Imperial Gala, 376.87 prey on Lebanon Red, and 276.76 prey on Granny Smith. Our results showed that predator performance was strongly affected by feeding on C. irani mites reared on different apple cultivars, and also a significant difference was seen in the hunting capacity of T. bagdasarjani on different apple cultivars.

Pathogen infection is one of the most important challenges threatening the success of mass rearing of natural enemies either in insectaries or in augmentative biological control programs. In this investigation, we studied the biological and population growth parameters of a naturally infected colony of the parasitoid wasp Habrobracon hebetor (Say) (Hymenoptera: Braconidae) over 20 generations (G1inf − G20inf) of rearing on Ephestia kuehniella (Zeller) (Pyralidae: Lepidoptera) under laboratory conditions. Based on morphological characteristics and ITS sequences, two types of fungal colonies were isolated from the diseased females and identified as Thermothielavioides terrestris and Aspergillus flavus. The results showed that although no significant differences were found in the female longevity and fecundity of H. hebetor on E. kuehniella up to G15inf, the duration of the immature period was extended as the number of generations increased. In addition, the intrinsic rate of increase (r) and finite rate of increase (λ) had no significant differences up to G8inf. The net reproductive rate (R0) of G15inf had no significant differences with G2inf, G8inf, and G10inf. On the other hand, in G15inf, R0 was significantly higher than G4inf, G6inf, and G20inf. The findings underscore the negative impact of fungal infection on population growth parameters compared with uninfected population. This study showed that naturally fungal infection of the parasitoid affected the population growth and life table parameters through mass rearing, compared and discussed with the healthy parasitoid.

Wolbachia are the most widespread intracellular alphaproteobacteria in insects with a variety of phenoptypic effects on the fitness and reproduction of their host, but much less is known about how these bacteria affect host behavior. In this study, we asked whether Wolbachia affects the foraging behavior of the parasitoid wasp Habrobracon hebetor (Hym.: Braconidae), an important biological control agent of many lepidopteran larvae. To test this, we analyzed the functional and numerical responses of Wolbachia-infected and uninfected (tetracycline cured) wasps, as well as morphological parameters. Functional response analysis showed Holling type II responses in both the Wolbachia-infected and uninfected females. The handling time and searching efficiency of Wolbachia-infected and uninfected females were similar, although the estimated maximum parasitism rate was shorter in infected females. Regardless of Wolbachia infection status, there was a negative non-linear relationship between the number of larvae parasitized by a female and an increase in the host density, reflecting a decrease in the total number of eggs laid. Our results also showed that Wolbachia had no effect on morphological traits of the parasitoid wasp. Together, these results suggest that Wolbachia which are prevalent in H. hebetor have limited impact on foraging behavior and morphology.

This study aims to explore the significant impact of soil fabric anisotropy on the ultimate bearing capacity of eccentrically and obliquely loaded shallow foundations overlying a geosynthetic-reinforced granular deposit. For this purpose, the well-established lower bound theorems of limit analysis (LA) in conjunction with the finite elements (FE) formulations and second-order cone programming (SOCP) are exploited to perform the bearing capacity estimations. The consideration of the soil mass’s inherently anisotropic response in the granular layer involves the utilization of distinct internal friction angles in various directions. The lower bound FELA framework adopted in this study incorporates both the pull-out and tensile mechanisms of failure in the reinforcement layer. The marked contribution of soil inherent anisotropy to the impacts of ultimate tensile strength (Tu) and embedment depth (u) of the geosynthetic reinforcement on the failure mechanism, bearing capacity ratio (BCR), and failure envelope of the overlying obliquely/eccentrically strip footing is rigorously examined and discussed. It is generally concluded that for a given embedment depth, failure envelopes of the surface footing in both V-H and V-M planes shrink appreciably with the increase in the soil anisotropy ratio as well as the decrease in the geosynthetic ultimate tensile strength. Moreover, the influence of soil inherent anisotropy on the overall bearing capacity of shallow foundations is more evident in the case of using strong reinforcement compared to the weak geosynthetic. The findings of this investigation demonstrate that overlooking the soil inherently anisotropic behaviour in the numerical analysis of shallow foundations would give rise to undesirable non-conservative and precarious designs.

Iranian false spider mite, Cenopalpus irani is one of main pests on apple trees and some fruit trees in Iran. The life table parameters of C. irani were determined on four apple cultivars (Kohanz Golab, Imperial Gala, Lebanon Red, and Granny Smith) under laboratory conditions at 25±1ºC, 60±5% RH, and a photoperiod of 16: 8 h (L: D). The longest and shortest developmental time of immature stages was observed in Kohanz Golab (46.02 days), and Granny Smith (22.60 days), respectively. The lowest and highest survival rate for whole immature stages was 82.85% and 90.00% on Kohanz Golab, and Granny Smith, respectively. The intrinsic rate of increase (r) ranged from 0.041 day-1 on Kohanz Golab to 0.089 day-1 on Granny Smith. The mean generation time (T) on the above-mentioned cultivars was 66.04, 55.28, 48.10, and 34.99 days, respectively. The fecundity was also affected by the cultivars; it was the lowest on Kohanz Golab (29.55 eggs/female) and highest on Granny Smith (37.93 eggs/female). The results of the data analysis of different apple cultivars based on some demographic parameters of C. irani mite showed that Granny Smith and Kohenz Gulab cultivars are the most sensitive and resistant hosts to this pest, respectively. The findings of the present study provide new information to design a more comprehensive IPM program for this pest in apple orchards.

This study presents a conceptual classification scheme to review the literature on improving the oxidation resistance of tungsten carbide by modifying the binder. The first parts of the article are dedicated to the specification of the databases, the search method, and the description of the criteria chosen to classify the articles. Then, the data collected are presented in statistical graphs according to the proposed classification scheme. The data analyzed show that most of the significant improvements in oxidation resistance are achieved with advanced production processes, especially HIP and SPS, which eliminate porosity to a very high degree. In addition, statistical studies showed that the use of new replacement binders, Ni3Al, Fe–based alloys, FeAl, and Al2O3, improved the oxidation properties in 75–100% of cases. Meanwhile, the use of high–entropy alloys (HEAs) as cermet binders may be the subject of future research for oxidation, given the recently published results of good mechanical properties.

The fall webworm, Hyphantria cunea (Drury, 1773) (Lepidoptera, Erebidae), is one of the most important pests of forest trees in northern Iran. In order to identify the native parasitoids of this pest a survey was conducted in Guilan province, in 2019. The larvae and pupae of the fall webworm suspected being parasitized, were collected from different host trees and wood piles, and reared under laboratory conditions until the parasitoids emerged. This pest was found parasitized with five species of Hymenoptera, Brachymeria lasus (Walker, 1841) (Chalcididae), Chouioia cunea Yang, 1989 (Eulophidae), Psychophagus omnivorus (Walker, 1835) (Pteromalidae), Pimpla rufipes Brulle, 1846, Virgichneumon dumeticola (Gravenhorst, 1829) (Ichneumonidae), and four species of Diptera, Compsilura concinnata (Meigen, 1824), Exorista larvarum (Linnaeus, 1758), Pales sp. (Tachinidae), and Megaselia scalaris (Loew, 1866) (Phoridae). Among them six species (e.g., P. rufipes, V. dumeticola, B. lasus, E. larvarum, C. concinnata and Pales sp.) are newly reported as the parasitoids of H. cunea from Iran.

Summary: In this paper, a family of single‐phase boost AC‐AC converters based on impedance network cells with symmetric bipolar operation is proposed. The proposed converters exhibit a range of voltage gains as a result of non‐inverting and inverting boost operations, which are influenced by the input voltage and various impedance source cells. The converters leverage inherent commutation to address the commutation problem without requiring snubber circuits and safe commutation strategy. Additionally, high‐speed switching is achieved by preventing power MOSFETs' body diode conduction and related poor reverse recovery issues. The design incorporates a simple and flexible switching strategy to produce step‐change frequency at the output, using only four switches to achieve both step‐changed frequency operation and output voltage regulation. Furthermore, by reducing the total stored energy of passive components, the proposed converters effectively decrease volume, weight, and cost. The operational modes of the converters are elucidated, and their key relationships are summarized in tabular format. Finally, experimental validation through a laboratory prototype confirms the performance accuracy of the proposed converters at frequencies 25, 50, and 100 Hz. [ABSTRACT FROM AUTHOR]

In this paper, a single switch transformer-less DC-DC converter with continuous input current for photovoltaic applications is proposed. The suggested configuration utilizes a CL1C2D2 structure to achieve a high voltage gain and alleviate voltage stress on the semiconductor components. The voltage gain of the proposed converter is enhanced through a reduction in the turn ratio of the coupled inductor, offering a significant benefit in minimizing the overall size of the converter. The reduction in the turns ratio of the coupled inductor results in lowered voltage stress on the semiconductor elements. Additionally, employing just one power switch in the converter simplifies control and reduces expenses. With its continuous input current, this converter is particularly well-suited for integration in photovoltaic systems. Simulation results conducted using PSCAD/EMTDC software validate the efficacy of the proposed power converter. Furthermore, the maximum power output of the photovoltaic module through an MPPT (Maximum Power Point Tracking) controller under varying irradiance levels is determined, and simulations are executed using PSCAD/EMTDC. [ABSTRACT FROM AUTHOR]