Feeding Scheme Research Articles

Base Station MIMO Antenna in 1 × 6 Array Configurations with Reflector Design for Sub-6 GHz 5G Applications

In this article, a base station array antenna in 1 × 6 configuration is proposed for sub-6 GHz 5G applications. Analyses have been performed on two orthogonally arranged dipole strips, a balun with various feeding schemes, and a reflector with different side walls. At the balanced feed position, aluminum is used to connect the feeding balun and the dipole through a hole. A single crossed antenna element of size 66 × 66 × 78 mm3 is fabricated using an FR-4 substrate with a dielectric constant of 4.4, 1.6 mm thickness, and an operating frequency band from 3.2 to 5.22 GHz. The radiating element provides a stable and high gain of 11–18 dB using reflectors with sidewalls. The proposed element is simulated, and its electrical downward tilt is investigated for a 1 × 6 array arrangement with dimensions of 642 mm × 112 mm × 90 mm. Various radiation performance parameters are measured, such as gain, FBR (>26 dB), HPBW, and XPD (>11.5 dB) at 60° in the H-plane. A reflection coefficient of less than −15 dB and port-to-port isolation of greater than 27 dB are achieved. Simulation and measurement of radiation patterns are performed for the operating frequencies of 3.2, 4.2, and 5.2 GHz.

Potential inert diets to supplement Artemia in larviculture of the giant Africa river prawn Macrobrachium vollenhovenii (Herklots, 1857) (Crustacea: Palaemonidae)

The protocol of culture of Macrobrachium vollenhovenii the main indigenous candidate for freshwater prawn culture in Africa is still under study. Though just few information exists, the transition of larvae from stage V to stage VI has been reported as the critical rearing period in larviculture. This study was to evaluate the efficiency of two locally diets to supplement Artemia in the feeding scheme from stage V to post larvae in the larviculture of this species. The two experimental diets were differentiated by the main source of protein: fish silage (Diet 1) and shrimp meat (Diet 2). One batch of larvae was cultured till stage V. The experiment itself was conducted in triplicate with three treatments: feeding Artemia exclusively (TA, control); fed partial replacement of Artemia with inert diet 1 (T1) or fed partial replacement of Artemia with diet 2 (T2). Larval development in T2 was significantly faster than TA and T1. Survival rate was significantly higher in T2 (12.64±1.2%) than TA (6.57±0.29%) and T1 (6.77±0.17%). The total length of larvae in T2 was significantly higher than TA and T1. Though the highest survival obtained in this study is still low, it’s however higher than those reported in other studies with this species. Also, the importance of finding alternatives to Artemia and cheaper diets remains very important.

Assessment of the impact of feeding technology of black-and-white breed heifers on growth and development indicators during the dairy period.

Proper cultivation of heifers largely determines the optimal manifestation of the genetic productivity of animals. The purpose of this study was to identify the optimal technology for growing black-and-white heifers in the dairy period to realize the genetic potential in the conditions of the northern region of the Republic of Kazakhstan, namely the Kostanay region. To conduct experiments on the farm, two groups of heifers of 10 heads each were formed, immediately after their birth. The selected groups differed in feeding technologies: the control group received the diet adopted on the farm, the feeding technology was changed for the experimental group in order to increase the intensity of heifer growth. The live weight and linear body sizes of heifers were monitored monthly. The new technological scheme of cultivation for the experimental group of heifers included the rejection of dairy feed at the age of two months and the use of ViaCorn 4 starter compound feed, as well as the active use of juicy and coarse feeds, unlike the heifers of the control group who were fed dairy feed until the end of the dairy growing period (up to 6 months). The live weight, average daily gain and linear body sizes of heifers of the experimental group significantly exceeded similar indicators of peers of the control group. The superiority in average daily live weight gains over the heifers of the control group averaged 287.6 g over 6 months. The change in the technological scheme of feeding towards the rejection of dairy feeds at 2 months and the addition of a starter, as well as compliance with the technology of milking colostrum in newborn calves in the experimental group contributed to the better development of the axial and peripheral skeleton, chest organs of animals, which will create prerequisites for the formation of highly productive cows of a pronounced dairy type. The concentration of total protein in the blood of the heifers of the experimental groups at 2 months of age was higher than that of the control group peers by an average of 1.89 g/l and at the age of 6 months - by 3.37 g/l, which indicates a higher protein metabolism in the blood of the heifers of the experimental group.

Effect of feeding bioactive compounds identified from plant extracts (4-hexylresorcinol, 7-hydroxycoumarin, and gamma-octalactone) on the productivity and quality of broiler meat.

Secondary bioactive compounds of medicinal plants exert anti-inflammatory, antimicrobial, antioxidant, and metabolism-modulating effects. This study aimed to investigate the effect of feeding 4-hexylresorcinol, as well as its combinations with gamma-octalactone and 7-hydroxycoumarin, on the digestibility of dietary nutrients, weight gain, and quality characteristics of the meat and liver of Arbor Acres broiler chickens. The following feeding scheme was applied on the chickens: Control, basal diet (BD); I experimental, BD + 4-hexylresorcinol at 0.5 mg/kg of live weight per day; II experimental, BD + 4-hexylresorcinol + gamma-octalactone at 0.4 mg/kg of live weight per day; III experimental, BD + 4-hexylresorcinol + 7-hydroxycoumarin at 0.1 and 0.15 mg/kg of live weight per day; and IV experimental, BD + 4-hexylresorcinol + gamma-octalactone + 7-hydroxycoumarin at 0.05, 0.15, and 0.01 mg/kg of live weight per day. Chickens in I, II, and IV experimental groups at the age of 35 days showed superior live weight than chickens in the control group. Supplementation with all the tested additives, except the combination 4-hexylresorcinol + 7-hydroxycoumarin, significantly increased the digestibility coefficients of dietary nutrients. Supplementation with the combinations 4-hexylresorcinol + gamma-octalactone and 4-hexylresorcinol + gamma-octalactone + 7-hydroxycoumarin significantly increased the amount of fat in the pectoral muscles. However, the mass fraction of fat in the thigh muscles of broiler chickens decreased in II, III, and IV experimental groups. The pectoral muscles of broiler chickens in experimental Group IV contained small amounts of lysine, tyrosine, histidine, leucine-isoleucine, methionine, valine, proline, threonine, serine, alanine, and glycine. Supplementation with pure 4-hexylresorcinol significantly reduced the levels of lysine, phenylalanine, histidine, leucine-isoleucine, methionine, valine, proline, threonine, and alanine in the thigh muscles. However, supplementation with pure 4-hexylresorcinol significantly increased the concentrations of P, Fe, Se, Zn, and B and decreased the concentrations of I, Ni, V, Al, and Pb in the pectoral muscles. Supplementation with the combination 4-hexylresorcinol + gamma-octalactone + 7-hydroxycoumarin resulted in the accumulation of Ca, Co, Fe, Mn, Se, Zn, and Li and a decrease in the concentrations of K, Mg, and V. Supplementation with all the tested additives, except the combination 4-hexylresorcinol + 7-hydroxycoumarin, exerted a positive effect on the indicators of live weight gain and dietary nutrient digestibility in broiler chickens. Supplementation with the combinations 4-hexylresorcinol + gamma-octalactone and 4-hexylresorcinol + gamma-octalactone + 7-hydroxycoumarin increased the amount of fat in the pectoral muscles but decreased it in the thigh muscles. Supplementation with all the tested additives decreased the concentrations of I in the pectoral muscles and Zn in the thigh muscles in all the experimental groups compared with those in the control group.

A Low-Cost Miniaturized Filtering Dielectric Resonator Antenna Based on SISL for 5G Applications

To realize a low-cost, miniaturized, and high selective design, the filtering dielectric resonator antenna (FDRA) for 5G applications is first proposed based on the substrate-integrated suspended line (SISL). The FDRA consists of two same rectangular DRs embedded in air cavities, which are fixed by the hollowed substrate rings. A T-shape feeder, rectangular feeder, and metalized holes are introduced to excite the fundamental <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm {TE}}_{\delta 11}^{x}$ </tex-math></inline-formula> mode of DRA. The substrate rings and DR are regarded as a composite dielectric to miniaturize the antenna and have effects on the radiation nulls. Because of the different loading effects from the different feeders, the resonance frequency of the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${\mathrm {TE}}_{\delta 11}^{x}$ </tex-math></inline-formula> mode excited by the different feeders is slightly different. Therefore, a wide bandwidth can be achieved. In the hybrid feed scheme, three radiation nulls are introduced near the edge of the frequency band without an extra filtering circuit. To improve the suppression level, the effective size of the radiator is increased by increasing the width of the substrate rings without changing the size of the whole structure. Therefore, two prototype antennas with different widths of substrate rings are designed, manufactured, and measured. Good agreement can be observed between simulated and measured results.

Study on a Multi-Point Differential Feeding Strategy for Design of Filtering Patch Antennas With Stopband Enhancement

In this article, a novel multi-point differential feeding technique is introduced and applied in the design of filtering patch antennas with a wide upper stopband. Different from the traditional differential feeding structure, the proposed method has four physical feeding points on the patch. Our analysis results indicate that the proposed feeding approach can not only effectively excite the desired fundamental TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\mathbf {01}}$ </tex-math></inline-formula> mode but also flexibly allow for the elimination of high-order modes by selecting suitable feeding positions. Just relying on this feeding method, unwanted harmonic radiations can be totally removed up to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4{f} _{\mathbf {0}}$ </tex-math></inline-formula> without any additional elements. For demonstration, a prototype of a stacked patch antenna with filtering response has been then designed. With resorting to the proposed feeding scheme, both driven and stacked patches are indeed able to support good excitation of TM <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$_{\mathbf {01}}$ </tex-math></inline-formula> mode with other harmonics to be suppressed, leading to a wide upper stopband performance. In addition, several radiation nulls are generated in the stopband to improve the filtering selectivity. Measured results agree well with the simulated ones, indicating that the designed differential antenna possesses enhanced fractional impedance bandwidths, high in-band gains, low cross polarization, as well as intrinsic wide stopband rejection, further verifying the proposed feeding concept.

A New Compact FSIW Fed Dielectric Resonator Antenna for Millimeter Wave Band Applications

Abstract A new waveguide feeding scheme of a rectangular DRA based upon the folded substrate integrated waveguide concept is presented. The most important characteristics of this antenna are a good radiation efficiency of above 87% at high frequencies which antenna operates and half transverse size of its feeding in comparison with other waveguide feeding schemes such as SIW and rectangular waveguide. The simulated results show an impedance bandwidth of 6.7% from 25.25 to 27 GHz and a good gain of at least 5 dB for this range.

Synthesis of Low Sidelobe Pattern with Enhanced Axial Radiation for Sparse Conformal Arrays Based on MCDE Algorithm

A hybrid optimization method for the synthesis of a sparse conformal array with the verification of a truncated cone antenna array is proposed in this manuscript. This array synthesis is studied aiming at enhancing axial radiation and reducing the peak sidelobe level (PSLL) by figuring out the optimal antenna element arrangement and corresponding feeding scheme. A multi-agent composite differential evolution (MCDE) algorithm is established by integrating a multi-agent system (MAS) with a differential evolution (DE) algorithm. In addition, a hybrid strategy method and a time-varying weighting factor are added to the mutation operator to accelerate convergence. Two examples of 64-element and 900-element truncated cone antenna arrays were synthesized. After forming a sparse antenna array out of the original full array, the number of antennas was decreased to 80% and 56.8%, respectively. The results show that the main beam of the sparse conformal antenna array is accurately fixed to the axial direction with the PSLL less than −20 dB at both the φ = 0° and φ = 90° planes, which proves the effectiveness of this method in conformal sparse array synthesis.

Rumen Microbial Predictors for Short-Chain Fatty Acid Levels and the Grass-Fed Regimen in Angus Cattle.

The health benefits of grass-fed beef are well documented. However, the rumen microbiome features in beef steers raised in a grass-fed regimen have yet to be identified. This study examined the rumen microbiome profile in the feeding regimes. Our findings show that the rumen microbiome of the grass-fed cattle demonstrated greater species diversity and harbored significantly higher microbial alpha diversity, including multiple species richness and evenness indices, than the grain-fed cattle. Global network analysis unveiled that grass-fed cattle's rumen microbial interaction networks had higher modularity, suggesting a more resilient and stable microbial community under this feeding regimen. Using the analysis of compositions of microbiomes with a bias correction (ANCOM-BC) algorithm, the abundance of multiple unclassified genera, such as those belonging to Planctomycetes, LD1-PB3, SR1, Lachnospira, and Sutterella, were significantly enriched in the rumen of grass-fed steers. Sutterella was also the critical genus able to distinguish the two feeding regimens by Random Forest. A rumen microbial predictor consisting of an unclassified genus in the candidate division SR1 (numerator) and an unclassified genus in the order Bacteroidales (denominator) accurately distinguished the two feeding schemes. Multiple microbial signatures or balances strongly correlated with various levels of SCFA in the rumen. For example, a balance represented by the log abundance ratio of Sutterella to Desulfovibrio was strongly associated with acetate-to-propionate proportions in the rumen (R2 = 0.87), which could be developed as a valuable biomarker for optimizing milk fat yield and cattle growth. Therefore, our findings provided novel insights into microbial interactions in the rumen under different feed schemes and their ecophysiological implications. These findings will help to develop rumen manipulation strategies to improve feed conversion ratios and average daily weight gains for grass- or pasture-fed cattle production.

SDG4 and the Ambiguity of Sustainable Development: The Case of Poor Schools in South Africa

The 2030 Agenda for Sustainable Development was conceived as a blueprint for development and an acknowledgment that poverty and multiple deprivations continue to plague large sections of the world’s population. Target 4.7 of SDG4, in particular, reads as follows: “By 2030, ensure that all learners acquire the knowledge and skills needed to promote sustainable development”. This article considers the question of how schools in contexts of extreme poverty and deprivation can sustain their continued existence. It aims to establish the specific nature of such contexts and engages in a discussion of the ethicality and complexity of imposing sustainable development content knowledge on children living at the edge of survival. Data from eight school principals were generated using a qualitative research approach that employed a series of in-depth interviews and onsite observations. The findings reveal the extent of community poverty and its effects on schools, the extent of neglect regarding poor schools and their struggles with sustainability, the extent of food insecurity and in-school feeding schemes, as well as the levels of desperation felt by school principals as they respond to the conditions they encounter. Teaching (and learning) the content of this Target 4.7 is likely to present a particularly complex challenge in those school contexts characterized by severe destitution and deprivation, given the content’s middle-classness in contradistinction to the immediate lived experience of the destitute.

Air-Filled SIW Remote Antenna Unit With True Time Delay Optical Beamforming for mmWave-Over-Fiber Systems

A low-complexity and efficient mmWave-over-fiber remote antenna unit (RAU) is proposed for broadband transmission and wide-angle squint-free beam steering in the full [26.5–29.5] GHz n257 5G band. It leverages an optical beamforming network (OBFN), implemented on a silicon photonics integrated circuit, and a broadband optically enabled 1x4 uniform linear array (ULA). The antenna elements (AEs) of the ULA are implemented in air-filled substrate-integrated-waveguide technology. They adopt an improved aperture-coupled feeding scheme to achieve high efficiency, high isolation and minimal back radiation over a broad frequency band. Each AE is compactly integrated and co-optimized with a dedicated opto-electrical transmit chain, maximizing the RAU’s performance, including beamforming flexibility and energy efficiency, while minimizing its size. The separately packaged OBFN implements true-time-delay beamforming by means of four switchable optical delay lines that are capable of discretely tuning the delay difference between AEs with a resolution of 1.6 ps, up to a maximum delay of 49.6 ps to fully exploit the ULA’s full grating-lobe-free scan range. The measured AEs are excellently matched in the [25.1–30.75] GHz band, exhibit high isolation ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ &gt;$</tex-math></inline-formula> 15 dB) in the operating band, and feature a stable peak gain of 6.8 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> 0.72 dBi with a beamwidth of at least 95 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> . Additionally, optical beamforming was successfully demonstrated by steering the RAU’s beam towards angles up to 51.8 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$^\circ$</tex-math></inline-formula> without grating lobes. The optically enabled 1 × 4 ULA successfully establishes a 64-QAM wireless communication link at 2.2 Gbaud (13.2 Gbps) while beam steering up to 50 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ ^\circ$</tex-math></inline-formula> with an error vector magnitude below 7.6%.

Eddy current loss estimation for direct drive wind turbine generators with superconducting excitation winding by numerical and analytical models

AbstractDirect drive wind turbine generators with superconducting excitation winding are studied with focus on the electromagnetic damper design. A semi‐analytical eddy current model is built for parametric design studies based on a vector potential approach. The considered generators employ open stator slots and exhibit strong saturation effects, so that an analytical expression for the source terms is not adequate. Whilst the field equations are solved analytically, an equivalent current loading, accounting for slotting effects and saturation, is obtained by magnetostatic models applying the 2D finite element method (FEM). The proposed framework for the extraction of the current loading is universal and may also be applied to other machine types (e.g., permanent magnet synchronous machines, [PMSM]). In relation to transient FEM models, a considerable time‐saving can be achieved, which is particularly beneficial in case of large models, for example, in case of fractional slot windings or intermittent feeding schemes. The eddy current loss in warm and cold rotor parts in a direct drive generator in the 7 MW power class are computed with the semi‐analytical and transient 2D FEM models under variation of the damper geometry and the stator winding configuration. Minimum damper dimensions as well as constraints regarding applicable stator windings are derived.

PHYSIOLOGICAL AND ZOOTECHNICAL SUBSTANTIATION FOR APPLICATION OF PROBIOTICS FOR REARING OF CALVES

One of the urgent tasks of dairy cattle breeding is to obtain viable young animals, while the main factors in this issue are survivability and productivity increase of calves. In this regard, the goal was set to study the effectiveness of Probitox and Olin probiotics in rearing technology of dairy calves from a physiological and zootechnical points of view. The experiment was carried out on young black-and-white cattle. The feeding conditions of experimental animals corresponded to the feeding scheme adopted on the farm. The differences among the experimental groups consisted in application of various probiotics - the first experimental group received Probitox in addition to the main ration, the second experimental group received Olin. Comparative effectiveness of two probiotics: Probitox and Olin was presented in the course of the study, they demonstrated effectiveness in rearing technology of dairy calves. Thus, the growth rates of calves of the experimental groups significantly exceeded the control parametres, on average, by 3.3% (P&lt;0.05). As far as average daily growth of young animals is concerned, a significant increase of thisparametre in the experimental groups was also noted - the average daily increase in the first experimental group was higher by 23.1%, in the second experimental group - by 18.7% in relation to the data of the control group. After assessing the hematological parameters of the young animals, it was found that introduction of probiotics into the ration did not adversely affect the functioning of the animals. The economic efficiency calculation showed that the profitability of production had a positive difference of 11% when using probiotics "Probitox" and "Olin" when compared to the control group.

Increasing the performance of the Far Eastern Railway traction power supply system

Introduction. The purpose of the study is to develop measures determined by the strategic programmes for the development of Russian railway transport based on the analysis of power supply schemes for the traction network of the Far Eastern Railway, a branch of Russian Railways.Materials and methods. Evaluation of the performance of the traction power supply system was made based on the analysis of the actual performance of the Far Eastern Railway section, as well as the theories of electrical engineering and power supply of the 25 kV AC electrified railway system.Results. Based on the analysis of the joint operation of the external and traction power supply systems of the Far Eastern Railway, four traction substations with low technical and economic indicators were identified. Network sections that feed the substations are a bottleneck in the traction power supply system. It is proposed to increase the efficiency by switching the connection of the windings of transformers of traction substations to the systems of external and traction power supply according to the typical star – delta scheme. Such a connection will ensure an increase in the speed of trains, a reduction in train succession time and losses of electricity, an increase in the quality of electric energy in the external power supply system and electric networks of the Far Eastern Directorate for Energy Supply (a structural subdivision of Transenergo, a branch of Russian Railways).Discussion and conclusion. Normalisation of the connection of four traction substations according to the feeding scheme is ensured by changing the phasing in such a way that the power supply of the two legs of one winding of the power transformer is transferred to two windings. Alignment of the current modules in the windings of transformers of traction substations makes it possible to reduce the voltage drop in the most loaded phase and, accordingly, increase the voltage in the traction network, which ensures an increase in the speed of trains and a reduction in passing intervals. Switching the power supply of the arms from one winding of the transformer to two reduces the loss of electrical energy in power transformers and the external power supply system. Reducing the current unbalance in the windings of the power transformer improves the quality of electrical energy in the system of external and district power supply. An increase in the service life of the power transformer is ensured by a decrease in the intensity of thermal wear of the insulation of the most loaded winding.

53 The Role of Veterinary Services on Nutrition Schemes, Management, and Health Practices for Sheep and Goats in Rural Ngaka Modiri Molema District Municipality, Northwest Province of South Africa

Abstract Poverty is a feature of rural households, and as a result, rural folks usually adopt low-input agriculture to alleviate poverty. Many households in Ngaka Modiri Molema District keep animals, particularly sheep and goats, for a variety of reasons, including as source of income, milk, and meat. However, they lack the management skills that are necessary for their livestock to increase their productivity. Inadequate animal management, including poor feeding and housing standards and poor application of proper animal health procedures are compounded by a lack of agricultural experience and low-input farming methods. In addition, poor animal nutrition, sickness and a high prevalence of parasites, and low animal production output further contribute to low overall productivity. Therefore, support offered by the veterinary services, and the impact these interventions have on sheep and goat farming among rural farmers need to be investigated. The present study will seek to describe the feeding schemes and management practices adopted by sheep and goat owners, as well as the role played by veterinary and extension services in the development of such practices. Health care provided to sheep goat farmers by the veterinary services will also be determined. A survey will be conducted in Ngaka Modiri Molema District Municipality, a rural area in North West Province of South Africa. The study population will consist of all farmers rearing sheep and goats, both female and male. Animal and farm information level data and general farm management practices will be collected via a questionnaire survey. Using the Statistical Kit for STATA (version 16), data will be examined by computing frequency, percentages, and proportions based on the characteristics of the sample population. This survey will help to provide opportunities for resource-poor farmers in rural areas to develop their flocks.

Chestnut tannins in broiler diets: Affecting intestinal development in different feeding phases.

It is known that high doses of various tannins could impair broiler growth, and this seems to be linked to a lowered protein availability. However, effects on protein digestion under the influence of hydrolysable tannins were minimal in previous research and literature. Other possible proposed reasons to explain reduced growth are scarce. In this experiment we studied the effect of hydrolysable tannins on body allometry by using different feeding schemes throughout the rearing period. In total 112 individually reared male Ross 308 broilers received a 3-phase basal diet with chestnut wood extract (+: 2,000 mg/kg) or not (–: 0 mg/kg) (Tanno-SAN®, Sanluc International NV, Belgium). This resulted in 2 groups during the starter period (S+, S–), 4 groups in the grower period (G++, G+−, G–+, G–) and 8 groups in the finisher period (F+++, F++−, F+−+, F+−−, F−++, F−+−, F−−+, F——). Similar to previous studies, growth reduction was also observed in this study. Effects were the largest in broilers that were given the tannins during the grower phase. At the end of each phase 8 broilers per group were euthanized and sampled. Liver, pancreas, pectoralis muscle, intestinal weights and intestinal length were recorded. The largest effects were seen on the intestine. Broilers that received tannins during the grower phase, had longer intestines at the end of the finisher period. Furthermore, histological differences between treatment groups were observed at the end of the grower period. Addition of tannins in the grower phase (G–+, G++) resulted in longer villi, whereas addition of tannins in the starter (G+−, G++) caused deeper crypts at the end of the grower phase, with the group (G–+) having the highest villi-to-crypt ratio. These results tentatively prove that tannins influence intestinal growth, both macroscopically as well as histologically. We hypothesize that the observed growth reduction with tannins could be the result of a changed energy and nutrient partitioning, i.e., more nutrients are directed to intestinal growth than for muscle growth.

A Compact Wideband Pattern Diversity Antenna for 5G-NR Applications

In this letter, a novel compact wideband antenna with broadside and conical diversity patterns is presented for fifth-generation (5G)-NR applications. The capacitive loading is implemented to enhance the port isolation and for size reduction (0.35 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.29 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> × 0.047 λ <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> ). With an extra slot mode introduced by the coupled feeding scheme, a wide impedance bandwidth is obtained. A miniaturized broadband 180° hybrid coupler is designed to provide in-phase and out-of-phase excitations. It is composed of a quarter-wavelength parallel coupled-line and lumped <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> components. As a result, conical and broadside diversity radiation patterns are achieved. The proposed antenna is analyzed, fabricated, and measured. Good agreement is achieved between the simulated and measured results. The measured overlapped −10 dB impedance bandwidth is 20.5% (3.16–3.81 GHz). The measured in-band isolation is better than 22.7 dB and the peak value achieves 34.7 dB. The proposed pattern diversity antenna exhibits good overall performance, including compact size, wide bandwidth, high isolation, and good radiation performance. Therefore, it is suitable for space-limited 5G-NR applications.

Isolation Enhancement of UWB MIMO rDRA for 5G Outdoor Applications

In this paper, a two-port Ultra-Wideband Multiple Inputs Multiple Outputs (UWB MIMO) rectangular Dielectric Resonator Antenna (rDRA) is proposed for 5G sub-6 GHz outdoor applications. An edged hole is inserted at the rDRA edge for isolation enhancement purposes. The effect of edged hole radius on isolation is investigated. Both UWB MIMO rDRA with and without edged holes are investigated for both parallel and orthogonal feed schemes (four scenarios). Isolation better than -22 dB is obtained for orthogonal orientation and edged hole rDRA. Surface current density distribution is used to explain that isolation enhancement. UWB bandwidth and high efficiency are obtained on the operating bands due to the usage of an aperture-coupled feed system and edged hole rDRA. The proposed antenna has two -6 dB operating frequency bands, the lower band (2.25 GHz – 2.52 GHz) and the higher band (3.6 GHz – 5.7 GHz). The Envelope Correlation Coefficient (ECC) and diversity gain DG are used to justify the MIMO antenna performance. Good agreement is obtained between measured and simulated results.

THE QUALITY OF GRINDING OF GRAIN FEEDS DEPENDING ON THE CONSTRUCTION PARAMETERS AND OPERATING MODES OF VIBRATING DISC CRUSHER

Full-fledged animal feeding is the basis for the successful functioning and effective development of the livestock production industry and can be ensured only if a sufficient amount of feed is produced, the loss of their nutritional value during their harvesting, storage, and also the correct preparation of feed for feeding is reduced. Grain feeds used at concentrated feed. They contain a large amount of nutrients that are easily absorbed. Their use in the feeding system allows you to balance the rations of animals in terms of energy, protein, amino acids. The compilation and selection of components of feed rations is carried out by technologists depending on the species, age group, morphological and biological indicators of animals and many other factors. At the same time, regardless of the technology and feeding scheme chosen by the specialist, concentrated feed based on wheat, barley, corn and other agricultural crops that have undergone preliminary technological processing remains an indispensable source of nutrients for animals. Moreover, a particularly important indicator that affects the productivity of animals is the quality of grinding concentrated feed. As a result of grinding feed, a significant number of parts are created from a larger surface area, which helps to speed up digestion and increase the absorption of nutrients. Grinding is one of the most energy-intensive operations used in the production of animal feed. Therefore, scientific research is aimed at minimizing the consumption of energy resources by crushers and increasing the grinding process is an urgent task. The article presents the results of experimental studies of the preparation of grain for feeding farm animals using a vibrating disc crusher, which was designed on the basis of the Department of Department of General Technical Disciplines and Labor Protection of the Vinnytsia National Agrarian University and passed preliminary experimental tests, which proved the prospects of its use in the processes of grinding grain raw materials. The choice of the range of design parameters was performed on the basis of assessing the compliance of the degree of grinding of the finished product with zootechnical requirements for the target fraction of the finished product.

A three‐state diplexer design using stub‐loaded resonator pairs

This letter presents a three-state diplexer design. By employing one port as the input while the other two as the output, the proposed circuit functions as three diplexers operating at different passbands. Owing to the planar stub-loaded resonator pair, two transmission zeros are generated at passband edges, ensuring sharp frequency selectivity for each filter passband. In addition, an asymmetrical feed scheme is adopted based on the discriminating coupling method, resulting in two other controllable out-of-band transmission zeros. These zeros are essential for isolation improvement between the three diplexer operations. For demonstration, the three-state diplexer is implemented. Compact size and measured isolation of more than 27.6 dB between the three states are obtained.