509 Late-Breaking: Effect of a Sensory Additive on Sow Reproductive Performance

The addition of a sensory additive to sow diets during the summer improved feed intake during lactation, and litter performance. The aim of this study was to evaluate the impact of the sensory additive on sow lactation performance during cooler temperatures. Three consecutive groups (n = 61 total) of sows were farrowed during winter (October, December and January). Sows were weighed, and back fat depth was measured, at 110 d of gestation prior to entering the lactation room, and again at weaning. The sows were sorted by parity, and then allotted by BW at d 110 to Control or 0.075% sensory additive (Luctamax® SowVive, Lucta S.A., Spain). Experimental diets were offered upon entry to the lactation room and fed through weaning. Feed disappearance was recorded every three days. Sows were fed 2.72 kg/head/day until farrowing, and then allowed to eat ad libitum from 24 hours post-farrowing until weaning. Data were analyzed using the PROC MIXED procedure of SAS as an RCBD with treatment as the fixed effect and group as a random effect. No differences were observed on sows feed intake (P > 0.4), 10th rib backfat thickness change (P = 0.632) and body weight change from d 110 of gestation to weaning (P = 0.65, Table 1). Sows fed the sensory additive lowered preweaning mortality by 4.9% (P = 0.051), and weaned an additional 1.42 piglets (P = 0.026) with similar weaning weights (P = 0.86) when compared to control. In conclusion, in the current study, lactation diets supplemented with a sensory additive improved litter performance and helped maintain sow body condition.

Influence of Microgroove Structure on Cutting Performance and Chip Morphology during the Turning of Superalloy Inconel 718

This study designed a new microgroove cutting tool to machine Inconel 718 and focused on the effect of microgroove structure on the cutting performance and chip morphology during the turning. A comparative analysis of the cutting force, cutting temperature, tool life, tool wear, and chip morphology of the microgroove cutting tool and the original cutting tool was conducted. The main cutting force and temperature of the microgroove cutting tool were reduced by 12% and 12.17%, respectively, compared with the original cutting tool. The microgroove cutting tool exhibited a significant improvement compared with the original cutting tool, which extended the tool life by up to 23.08%. Further, the microgroove cutting tool distorted the curl radius of the chips extensively. The experimental results showed that the microgroove structure can not only improve the tool life, but also improve the chip breaking effect.

Understanding targeted energy transfer from a symmetry breaking perspective

Targeted energy transfer (TET) represents the phenomenon where energy in a primary system is irreversibly transferred to a nonlinear energy sink (NES). This only occurs when the initial energy in the primary system is above a critical level. There is a natural asymmetry in the system due to the desire for the NES to be much smaller than the primary structure it is protecting. This asymmetry is also essential from an energy transfer perspective. To explore how the essential asymmetry is related to TET, this work interprets the realization of TET from a symmetry breaking perspective. This is achieved by introducing a symmetrized model with respect to the generically asymmetric original system. Firstly a classic example, which consists of a linear primary system and a nonlinearizable NES, is studied. The backbone curve topology that is necessary to realize TET is explored and it is demonstrated how this topology evolves from the symmetric case. This example is then extended to a more general case, accounting for nonlinearity in the primary system and linear stiffness in the NES. Exploring the symmetry-breaking effect on the backbone curve topologies, enables the regions in the NES parameter space that lead to TET to be identified.

CROSSKILL AND STAR-WHEELED ROLLERS. FUNCTIONAL AND DYNAMIC TESTS

Experimental field research of crosskill and star-wheeled rollers similar by design provides their developers and users with information on understanding their design and functional features. The purpose of the research is to compare the functional features of crosskill and star-wheeled rollers according to the criteria of clods breaking effect, compacting action, resistance to sticking in the range of pre-sowing and surface tillage depth. Methods and materials. Dynamic tests involved the study of three types of rollers. The research hypothesis assumed that the selected criteria for evaluating the work of rollers (intensity of breaking of clods, compacting action of rollers, intensity of bottom compaction and performance of rollers at high soil moisture) depend on roller pressure and different speed regimes, as they are derived from the shape of work surfaces. Sub-criteria studies were supposed to be carried out on the same type of soil: clods breaking characteristics on dry W = (10… 12) %, compacting effect on physically mature soil W = (15… 20) %, efficiency at high humidity - W = (25… 27) %. Evaluation of soil characteristics was performed by thermostatic-weight method according to the generally accepted method of "cutting ring" [Kaczynski NA, 1947], according to the volume of the cylinder 100 cm3. To determine the intensity of bottom compaction used the methodology and technical means of L. Pogorilyy UkrNDIPVT development. Statistical analysis of experimental data was performed by the method of analysis of variance according to [Dospekhov, 1985] and interpreted by standard computer programs Excel in the form of graphs. Results. The intensity of clods breaking with a classic roller is the lowest and depends on the speed of movement. The intensity of breaking by the modernized roller is approximately 1.1 times higher and with increasing speed is almost stable. The intensity of clods breaking by a specialized roller is the highest and almost (10...20) %, respectively, exceeds the previous two rollers and does not significantly depend on the increase in speed. The greatest compaction of the soil (the height of the layer to which the pre-prepared soil asked after the passage of the roller) is characteristic of a specialized roller, which is almost (1.5…1.7) times higher than the classic and modernized, respectively. Depending on the depth of pre-tillage (5…10) cm, compaction by rollers varies approximately twice. The greatest intensity of compaction of a bottom is provided by the specialized roller, and modernized and classical condense accordingly in (1,2…1,4) times below. The specialized roller sticks the fastest, which is facilitated by the 4-tier arrangement of working surfaces and their maximum in comparison with others contact with the ground. Sticking of the modernized roller surface is as that of the specialized. The classic roller surface remains clean for the longest time. Conclusions. The classic roller compacts both the upper and lower horizons of the soil well enough, brings little moisture to the surface, has a medium clods breaking effect, can be recommended for a wide range of works, but its primary purpose is cultivating after sowing; as a compromise it can be used for pre-sowing tillage with good quality indicators. The upgraded roller compacts the top layer of the soil well, carries away little moisture, mulches the surface, distributes the effort well at different depths of cultivation and can be recommended primarily for pre-sowing tillage; as a compromise solution can be used after sowing with good quality indicators. Specialized roller – star-wheeled, has good penetrating ability, works most actively, providing the best clods breaking effect, slightly carries away wet horizons on the surface; can be recommended for leveling and use on the soil after its main cultivation. Each of the studied rollers can be used to some extent in all these technological operations, but the best result will be achieved taking into account their characteristics, type and period of execution.

High precision methods for solving a system of cold plasma equations taking into account electron–ion collisions

High precision simulation algorithms are proposed and justified for modelling cold plasma oscillations taking into account electron–ion collisions in the non-relativistic case. The specific feature of the approach is the use of Lagrangian variables for approximate solution of the problem formulated initially in Eulerian variables. High accuracy is achieved both through the use of analytical solutions on trajectories of particles and due to sufficient smoothness of the solution in numerical integration of Cauchy problems. Numerical experiments clearly illustrate the obtained theoretical results. As a practical application, a simulation of the well-known breaking effect of multi-period relativistic oscillations is carried out. It is shown that with an increase in the collision coefficient one can observe that the breaking process slows down until it is completely eliminated.

Inhomogeneous Superconductivity and the ‘Pseudogap’ State of Novel Superconductors

This chapter discusses the high-Tc oxides, which display many unusual properties above Tc, especially for the underdoped compounds. One can observe some features typical for the superconducting state, such as the energy gap, anomalous diamagnetism, and the isotope effect; they coexist with finite resistance. These features are caused by an intrinsic inhomogeneity of the compound. Various energy scales (Tc, Tc*, T*) can be introduced. The system contains a set of superconducting ‘islands’ embedded in a normal metallic matrix. The inhomogeneity is caused by the statistical nature of doping and the pair-breaking effect. The formation of a macroscopic superconducting phase (at T = Tc) corresponds to the transition, which is of a percolative nature. The resistive and Meissner transitions are split. The granular superconductors are inhomogeneous and their properties are similar to those of doped systems. The ordered doping should lead to an increase in the value of the critical temperature.

Test on Rigid-flexible Composite Anti-breaking Measure for Tunnels across Stick-slip Fault

In this paper, based on the F8 stick-slip fault section of Longxi Tunnel in China, the effect of the anti-breaking measure of rigid-flexible composite (reinforcement of the secondary lining & construction of the reducing dislocation layer between the primary support and the secondary lining) is studied by using the method of indoor model test in order to improve the anti-breaking performance of the tunnel across stick-slip fault in the actual tunnel engineering. The test results show that the anti-breaking effect is limited by adopting structural strengthening measures to resist the influence of stick-slip dislocation on the tunnel structure and the anti-breaking effect is obvious by adopting the measures of reducing dislocation layer only. However, the structural safety of the tunnel with stick-slip fault in the strong seismic intensity area can be greatly improved by adopting the anti-breaking measure of rigid-flexible composite, and the structural safety factor can be significantly improved. The research results of this paper can provide a reference for the anti-breaking design of the tunnel across stick-slip fault in the high seismic intensity area.