Predicting fully-developed channel flow with zero-equation model

A new zero-equation model (ZEM) is devised with an eddy-viscosity formulation using a stress length variable which the structural ensemble dynamics (SED) theory predicts. The ZEM is distinguished by obvious physical parameters, quantifying the underlying flow domain with a universal multi-layer structure. The SED theory is also utilized to formulate an anisotropic Bradshaw stress-intensity factor, parameterized with an eddy-to-laminar viscosity ratio. Bradshaw’s structure function is employed to evaluate the kinetic energy of turbulence k and turbulent dissipation rate epsilon . The proposed ZEM is intrinsically plausible, having a dramatic impact on the prediction of wall-bounded turbulence.

On one problem, associated with lateral oscillations of elastic-viscous-relaxating rod

We obtain the solution of the problem about lateral oscillations of elastic-viscous-relaxating rod of finite length, variable profile, and variable momentum of rotation inertia of rod elements about the axis that is perpendicular to oscillation plane.

Investigation of the transverse and longitudinal moments at the transverse free end of deck slab cantilevers subjected to CHBDC truck loading

Clause 5.7.1.3 of the Canadian Highway Bridge Design Code (CHBDC) specifies an equation for the calculation of transverse moment intensity (My) in the deck slab cantilever due to truck loading in a slab-on-girder bridge system. Also, it states that the transverse moment intensity shall be assumed 2My for the locations within a distance equal to cantilever length of the transverse free end of the deck slab cantilever. However, CHBDC design values do not consider the effects of barrier length, variable thickness of the barrier wall and shape of the cantilever’s edge stiffening on the response. In addition, the longitudinal moment on the deck slab cantilever due to truck loading is as yet unavailable. Thus, a parametric study was conducted, using the finite element modelling, to investigate the effect of these key parameters in the transverse and longitudinal moments at the region of the transverse free edge of deck slab cantilever. Based on the data generated from this parametric study, imperial equations for the transverse and longitudinal moments at the transverse end of the deck slab cantilever were deduced.

Investigation of the transverse and longitudinal moments at the transverse free end of deck slab cantilevers subjected to CHBDC truck loading

Clause 5.7.1.3 of the Canadian Highway Bridge Design Code (CHBDC) specifies an equation for the calculation of transverse moment intensity (My) in the deck slab cantilever due to truck loading in a slab-on-girder bridge system. Also, it states that the transverse moment intensity shall be assumed 2My for the locations within a distance equal to cantilever length of the transverse free end of the deck slab cantilever. However, CHBDC design values do not consider the effects of barrier length, variable thickness of the barrier wall and shape of the cantilever’s edge stiffening on the response. In addition, the longitudinal moment on the deck slab cantilever due to truck loading is as yet unavailable. Thus, a parametric study was conducted, using the finite element modelling, to investigate the effect of these key parameters in the transverse and longitudinal moments at the region of the transverse free edge of deck slab cantilever. Based on the data generated from this parametric study, imperial equations for the transverse and longitudinal moments at the transverse end of the deck slab cantilever were deduced.

A smooth optimized input shaping method for two-dimensional crane systems using Bezier curves

Conventional input shaping commands have been successfully employed to suppress residual vibration in the payload rest-to-rest transportation process. Most of these methods introduce an impractical large and sudden variation on the acceleration profile. This paper presents a new smooth command input with adjustable time length and limited jerks. The command input is generated from the trolley displacement using a Bezier curve function by adjusting the position of the control points, which were divided into boundary and intermedium points. The boundary control points are selected to accurately move the trolley to its desired position with zero velocity and acceleration at the closing motion. The positions of the intermedium points were optimized using a particle swarm scheme for reducing maneuvering time while suppressing the payload oscillations at the end of the process and satisfying physical system constraints. Several cases were discussed for fixed cable length, variable cable involving single and multi-hoisting mechanisms, and different maneuver times. Simulated results were validated experimentally on a laboratory size crane. The results demonstrated that the proposed input Bezier-curve shaper provides an effective, reliable, and practical technique to be used for the payload transportation process. Moreover, the proposed method can generate asymmetrical acceleration and deceleration motions, which cannot be achieved using existing smoother commands.

Effect of Wing Length on the Prevalence of Trypanosomes in Glossina Morsitans Morsitans in Eastern Zambia

BackgroundTsetse flies (Diptera: Glossinidae) transmit trypanosomiasis (sleeping sickness in humans and nagana in livestock). Several studies have indicated that the age, sex, site of capture, starvation and microbiome symbionts, among others, are important factors influencing trypanosome infection in tsetse flies. However, reasons for a higher infection rate in females than in males still largely remain unknown. As species and sexes of tsetse flies of larger body size are the most mobile and the most available to stationary baits, it was hypothesized in this study that, the higher trypanosome prevalence in female than in male tsetse flies was because females were larger than males.Materials and methodsBlack screen fly rounds and epsilon traps were used to collect tsetse flies in eastern Zambia. Wing vein length was measured and the presence of trypanosomes was examined by microscopy. Principal component method was carried out to determine which variables had potential to be used as predictor variables. The multilevel binary logistic regression method was applied on whole data, one-method data and one-sex data sets to evaluate the hypothesis. ResultsA total of 2,195 Glossina m. morsitans data were evaluated (1,491 and 704 males and females, respectively). The wing length variable contributed the highest variance percentage (39.15%) to the first principal component. The wing length variable showed significant influence on prevalence of trypanosomes when the whole data set was analyzed. The log odds for the prevalence of trypanosomes significantly increased by 0.123 (p = 0.032), per unit increase in wing length. Moreover, moving from females to males, wing length significantly reduced by 0.150 (p < 0.0001) and females had higher trypanosome prevalence rates than males, though not always significant. ConclusionWing length is an important determinant factor for trypanosome prevalence in G. m. morsitans and could partially explain the higher prevalence of trypanosomes in females than in males. To verify this status, however, it’s clear that, reasonably representative population data is required for analysis – a serious challenge with the current tsetse sampling methods. Nonetheless, analysis of combined data from mobile and stationary methods that includes both sexes data, could verify the status.

The ability to punch in the front for students of pencak silat uns achievement (Correlational Study Viewed from Eye-Hand Coordination, Arm Length and Arm Power)

<p>The aim of this study was to determine the interaction of eye-hand coordination, arm length and arm power with the ability to punch in front of the students of UNS Pencak Silat achievement coaching. <br />Material and methods. The design or research design used is to use descriptive methods with correlational study techniques (correlation design). This research will describe the relationship and the amount of contribution between eye-hand coordination, arm length and arm power with the ability to punch ahead in the Pencak Silat sport. The population in this study were all students of UNS pencak silat achievement coaching which included fostering the achievements of the Faculty of sport, Tapak Suci student activity units, PSHT student activity units, Merpati Putih student activity units and student self-defense units. <br />Results. Based on the results of research and the results of data analysis that has been done, the following conclusions can be obtained: There is a significant relationship between eye-hand coordination, arm length and arm power with the ability to punch in front of pencak silat with a significant value F count = 64,99 &gt; F table = 2,81. <br />Conclusions. Contribution of eye-hand coordination is the variable that has the most dominant contribution, then followed by the arm power variable and the smallest contribution is the arm length variable. Meanwhile the remaining 19.1% is contributed by factors other than those represented by independent variables. Predictions from researchers of these other factors could have been influenced by training factors or other physical condition factors that also supported the ability to punch in front of pencak silat.</p>

RESPON PERTUMBUHAN BIBIT LADA (Piper nigrum L.) PADA APLIKASI PEMBERIAN BERBAGAI KOMPOSISI N:P:K DAN KONSENTRASI POC

This research was carried out at the Darul Mukhlisin Islamic Boarding School in Padang Lampe, Muslim University of Indonesia, Pangkep Regency, South Sulawesi, which took place from March to September 2019. The study was aimed at analyzing the effect of the composition of N: P: K on the growth of pepper seedlings, analyzing the effect of the concentration of Organic Fertilizers Liquid (POC) on the growth of pepper seedlings, analyzing the interaction between giving the composition of N: P: K and giving POC on the growth of pepper seedlings. This research was compiled using a Randomized Group Design (RBD) consisting of two factors. The first factor is the composition of N: P: K consisting of: N: PK 1 : 0 : 0 / plant, N: P: K 1 : 1 : 1 / plant, N: P: K 2 : 1 : 1 / plant and N : P: K 2 :1 : 2 / plant. The second factor is the concentration of Liquid Organic Fertilizer consisting of no POC, POC 0.05% / liter of water, POC 0.10% / liter of water and POC 0.15% / liter of water. The results showed that the best effect on the use of the composition N: P: K on the length of the shoot, number of leaves and leaf area of pepper seedlings. The use of liquid organic fertilizer concentration of 0.10% / liter of water gives the best effect on shoot length, number of shoots, and number of leaves and leaf area, and there are significant interactions between the composition factors of N: P: K and POC concentration on the shoot length variable of pepper seedling growth.

Characterization of Electromagnetic Wave Absorbers with Broadside SRR Method on C-Band

Electromagnetic wave absorber is a material that can reduce the energy available in electromagnetic waves. Electromagnetic wave absorber can be used to reduce interference in wireless communication devices so as not to quickly suffer damage, as a layer in the room free of reflection and to reduce radar cross section of an object detected in radar tracking applications. In this paper, a discussion about the use of the broadside form using the Split Ring Resonator (SRR) method as an absorber of electromagnetic waves and its characteristics in C-Band. Broadside shape is obtained from the initial form of a square which is developed into a square resonator and then given a gap at the end of the resonator. The results show that the SRR broadside form can be used as an absorbent of electromagnetic waves on the C-Band, precisely the frequency of 6.41 GHz with absorption rates reaching 99.99% and bandwidth of 0.077 GHz with dimensions of 7 mm. From the experimental results, it can also be seen that the change in the gap length variable in the SRR broadside shape is the most influential in changing the resonant frequency value and the amount of bandwidth produced.