Flexibility Coefficients Research Articles

Determination of dynamic loads in the crane lifting mechanism

Loading and unloading is an integral part of the technological process of construction. To perform these works mostly use cranes of different types.
 To ensure trouble-free operation and increase the reliability of cranes in the calculation of structures and components of their work equipment, it is important to take into account dynamic loads, which are several times higher than static loads.
 Elements of dynamic loads of the crane lifting mechanism are its elastic components - ropes and shafts, which are deformed under the action of loads. The magnitude of this deformation of the elements are taken into account by the coefficients of elasticity or flexibility of linear and torsional or their inverse value - the coefficients of rigidity. These coefficients depend on the linear or angular deformations, respectively.
 Due to the fact that the mechanism of lifting a load consists of a large number of elastic elements, the addition and solution of equations to determine these coefficients becomes a difficult task. In order to simplify the equations and these calculations, the paper recommends the above scheme of calculations according to which the rest of all elements of the mechanism are reduced to its first element (engine). This greatly simplifies the equations to be solved and determines the values ​​of the coefficients of elasticity or stiffness of the elements of the dynamic loads of the mechanism of lifting the load of cranes.
 According to a similar scheme is also determined by the moments of inertia of the mechanism of lifting the load during periods of acceleration and deceleration, the components of the values ​​that affect them. The equations for determining the terms of transients of the lifting mechanism (duration of acceleration and braking) are derived.
 The method of determining the coefficients of elasticity and stiffness of the elements of dynamic loads, moments of inertia, duration of acceleration and deceleration of the lifting mechanism can greatly simplify the solution of complex equations and determine their values ​​with sufficient accuracy.

Laterally loaded piles and pile groups partially embedded in transversely isotropic fractional viscoelastic saturated soils

This paper investigates the time-dependent behaviour of laterally loaded piles and pile groups partially embedded in stratified transversely isotropic (TI) saturated soils. The partially embedded single pile in stratified soils is regarded as a Timoshenko beam, and its total stiffness matrix can be assembled by using the finite element method (FEM). Based on the fractional viscoelastic model for solving non-axisymmetric consolidation of stratified cross-anisotropic media developed before, the solution for a partially embedded single pile is obtained by combining the boundary element method (BEM) and the extended precise integration solution of the media. Considering the interaction between piles in a pile group and the load distribution from the pile cap to pile tops, the solution for the partially embedded pile group is derived by extending the solution of single piles. The accuracy and efficiency of the proposed solution is verified with existing literatures, and some examples are designed to investigate the effects of the embedment ratio, the transverse isotropy, the slenderness ratio, the fractional derivative order, the flexibility coefficient and the pile spacing. Numerical results show that the embedment ratio and fractional derivative order are essential parameters that significantly affect the rate of the time-dependent response of the partially embedded lateral loaded piles.

Feasibility of Onboard Smartphones for Railway Track Geometry Estimation: Sensing Capabilities and Characterization

The performance and sensitivity of smartphone sensors developed rapidly in recent years. Due to their accessibility and low costs compared to other industrial solutions, the use of smartphone sensors has become more and more common. In this article, the validity and reliability of a smartphone application in railway track geometry estimation are tested on a conventional rail line. This work focused on Galaxy S-series smartphones of Samsung and proposes an evaluation of the onboard sensing capabilities of their inertial sensors with the comparison of synchronous measurements by a multi-functional Track Recording Vehicle equipped with a contactless Track Geometry- (TGMS), and a Vehicle Dynamic Measuring System (VDMS). The raw accelerometer recordings showed a high-degree correlation with VDMS in both signal magnitude and waveform. The accuracy of gyroscope angular tracking in heading and pitching angle calculation was in the range of 0.2°–0.6°, which allowed the acceptable estimation of the central angle and the radius of horizontal curves. Based on the kinematic analysis techniques, the roll flexibility coefficient of the vehicle was determined, which allowed calculating the cross-level and the twist of the track. Furthermore, the local extreme values of the roll-rate gyro correlate with the isolated track geometry defects of the track twist gathered by TRV’s TGMS. Despite its limitations, the application of smartphones represents a prospective technological opportunity to explore new approaches and support rail asset management.

Results of estimating adaptability of sainfoin varieties in the south of the Rostov region

The purpose of the study was to estimate such adaptability parameters, as a linear regression coefficient, stress resistance, genetic flexibility and stability coefficient, according to the traits “green mass productivity” and “dry matter productivity”. The objects of the study were 6 sainfoin varieties developed by the ARC “Donskoy”. The variety ‘Zernogradsky 2’ was taken as the standard one. Sowing was carried out in the spring with the SSFC-7 seeder in its pure form, without a cover crop. A seeding rate was 5 million germinated seeds per 1 ha. The area of the plot was 20 m2, with fourfold repetition. The estimation according to the indicators of ecological adaptability was performed according to the S. A. Eberchart and W. A. Russel (1966) as presented by V. A. Zykina et al. (2011), calculation of stress resistance and genetic flexibility was established according to A.A. Goncharenko (2005). The results of the analysis of variance have shown a significant influence of factor B (conditions) both on the variability of productivity of green mass (79.12 %) and dry matter (75.38 %). All the studied sainfoin varieties according to the years and sowing significantly exceeded the indicators of the standard variety. The most productive of them, the new variety ‘Atamansky 20’, formed on average 30.9 t/ha of green mass and 8.3 t/ha of dry mass, with fluctuations over the years, respectively, 24.8–44.9 t/ha and 6.4 –12.1 t/ha. The sainfoin varieties differ in the response of green and dry mass productivity to changing environmental conditions. The varieties ‘Zernogradsky 2’, ‘Atamansky’ and ‘Atamansky 20’ demand to improve conditions when cultivated for green feed and hay (bi > 1), while the varieties ‘Veles’, ‘Sudar’ and ‘Shuravi’ respond less well to improved environmental conditions and are more adaptable (bi < 1). The varieties ‘Veles’, ‘Sudar’ and ‘Shuravi’ are highly resistant to stress, while the varieties Zernogradsky 2’, ‘Atamansky’ and ‘Atamansky 20’ have a narrower range of adaptive capabilities of stress resistance. A higher correspondence between a genotype and environmental factors and high genetic flexibility were found in the variety ‘Atamansky 20’.

Bilayer Hydrogels with Low Friction and High Load-Bearing Capacity by Mimicking the Oriented Hierarchical Structure of Cartilage.

Natural articular cartilages exhibit extraordinary lubricating properties and excellent load-bearing capacity based on their penetrated surface lubricated biomacromolecules and gradient-oriented hierarchical structure. Hydrogels are considered as the most promising cartilage replacement materials due to their excellent flexibility, good biocompatibility, and low friction coefficient. However, the construction of high-strength, low-friction hydrogels to mimic cartilage is still a great challenge. Here, inspired by the structure and functions of natural articular cartilage, anisotropic hydrogels with horizontal and vertical orientation structure were constructed layer by layer and bonded with each other, successfully developing a bilayer oriented heterogeneous hydrogel with a high load-bearing capacity, low friction, and excellent fatigue resistance. The bilayer hydrogel exhibited a high compressive strength of 5.21 ± 0.45 MPa and a compressive modulus of 4.06 ± 0.31 MPa due to the enhancement mechanism of the anisotropic structure within the bottom anisotropic hydrogel. Moreover, based on the synergistic effect of the high load-bearing capacity of the bottom layer and the lubrication of the surface layer, the bilayer hydrogel possesses excellent biotribological properties in hard/soft (0.032) and soft/soft (0.028) contact, which is close to that of natural cartilage. It is worth noting that the bilayer oriented heterogeneous hydrogel is able to withstand repeated loading without fatigue crack. Therefore, this work could open up a new avenue for constructing cartilage-like materials with both high strength and low friction.

Dynamic modeling and analysis of flexible micro-porous piezoelectric sensors applicable in soft robotics

With recent advances in system integration technologies, numerous efforts have been made to develop soft piezoelectric sensors for various engineering and healthcare applications. Using flexible and sensitive materials is crucial for designing soft sensors in order to maximize their efficiency and integrability. Micro-porous PU-PZT composite is a recently designed piezoelectric particulate composite material with an improved flexibility and piezoelectric voltage coefficient over common piezoelectric ceramics that makes it a promising candidate for application in soft sensors. In this study, we investigate the dynamic response and sensitivity of the micro-porous PU-PZT composite for applications in soft sensors in both 33 and 31 modes using energy methods. By using the effective field method, the micro-porous PU-PZT composite material properties were extracted and optimized based on the partially experimentally measured properties in order to get a complete picture of the properties of the material. In addition, the effects of changing the sensor geometry by varying the thickness and adding an extra layer between the piezoelectric layers are studied. Finally, a large area sensor based on micro-porous PU-PZT composite is simulated in finite element software, and the effect of several parameters on sensor’s performance is investigated. Dynamic analysis of the sensor shows high sensitivity in both 31 and 33 modes which is a significant improvement compared to the commonly used bulk piezoelectric ceramics. This work has demonstrated that due to the high output voltage and structural flexibility of the micro-porous PU-PZT composite, a flexible large-area sensor would be a suitable choice for artificial skins and smart gloves.

Wood Fiber Characteristics of Underutilized Poplar Species and Comparision with P. deltoides in Terms of their Pulp and Paper Quality

The pulp and Paper industries are growing at a tremendous rate. To satisfy the raw material supply and sustainability of their future industries need an alternative resource from fast-growing tree species. Poplar is one of the world’s fastest-growing lightwood trees with its used in several industries. The present work relies on the comparative fiber morphological dimensions of four species of poplar i.e. Populus alba L, Populus ciliata Wall. ex Royle, Populus euphratica Oliv, and Populus nigra L. The quality of pulp and paper was directly related to the fiber dimensions i.e., fiber length, fiber lumen diameter, and fiber wall thickness. A number of wood properties related to paper quality were also derived from the fiber dimensions including the Runkel ratio, flexibility coefficient, solid factors, luce’s-shape factors, slenderness ratio and wall coverage ratio. The mean value of fiber length, fiber diameter, fiber wall thickness and basic density of these four species ranged from 919-1425 μm, 19.71-25.85 μm, 2.72-4.99 μm and 0.38-0.54 g cm⁻¹ respectively. The prominent objective was to compare the fiber quality of these four poplar species within among self and also with an exotic poplar species Populus deltoides and other fast-growing tree species.

FIBRE SOURCING FOR THE NIGERIAN PULP MILLS: EVALUATION OF SUITABILITY INDICES OF SELECTED NIGERIAN RAINFOREST WOOD FIBRES

To find a lasting solution to the problem of suitable fibre for pulp and papermaking in Nigeria, fibre suitability indices of nineteen wood species native to the rainforest zone of Nigeria were evaluated. Matured stems of the species were sourced and prepared for maceration. The fibre characteristics of the wood were carried out following ASTM D-1030-95 and ASTM D-1413-61. The fibres obtained were observed with the aid of a microscope and measurements of their morphology were done. A minimum of 25 fibres were measured for each species for accuracy. Selected morphological indices such as Runkel Ratio (RR), Flexibility Coefficient (FC), Slenderness Ratio (SR) as well as Rigidity Coefficient (RC) of the wood fibres were estimated. The results showed that the fibres lenght fall under short (1.05–1.36), medium-long (1.52–1.75), and long (2.0 mm) fibres criteria. All derived morphological indices showed significant variations from species to species. All fibres are not rigid and exhibited good SR with moderate rigidity and good felting power. They were all elastic; R. heudolotii and P. macrocarpa exhibited high elastic nature. They all have FC ≥ 50 and pass the RR ≤ 1, acceptable value for paper-making fibre except P. biglobosa and M. excelsa. The flexibility coefficients are in the range of 0.50 and 0.81. All the species pass the SR > 33 acceptable value for paper-making fibres. The species if harnessed as fibre blends in pulp and paper making furnish will help to solve the problem of inadequate long fibres for paper production in Nigerian pulp mills.

Evaluation of fiber characteristics and basic density of Acacia melanoxylon (R.Br.) grown in Ethiopia for pulp and paper making

The fiber characteristics and basic density of Acacia melanoxylon were investigated for its potential as a raw material for pulp and paper production. Six trees from the even-aged stand and similar diameter class were selected randomly from the Chencha district of Ethiopia. Wood disks were systematically cross-cut from a log along tree height levels, at the bottom (10%), middle (50%) and top (90%) of the merchantable height and blocks of wood (2 cm x 2 cm x 2 cm) were taken from pith to periphery at near pith (10%), middle (50%) and near bark (90%) of disk radius. Fiber maceration and basic density were determined, by 50% nitric acid solution and water displacement method respectively. All the data were analyzed using a two-way analysis of variance at α = 0.05. The fiber characteristics of the selected trees; the fiber length, fiber diameter, lumen diameter and cell wall thickness were measured while the-slenderness ratio, Runkel ratio, flexibility coefficient and wall coverage ratio of the fibers were derived from the measured fiber dimensions. The result showed that- the overall mean were, 1.04 mm, 21.60 µm, 15.36 µm, 3.75 µm, 0.48, 48.05%, 71.10%, 0.34 and 0.56 g/ml, for fiber length, fiber width, lumen diameter, cell wall thickness, Runkle ratio, slenderness ratio, flexibility ratio, wall coverage ratio and basic density, respectively. Generally, Acacia melanoxylon wood is suitable for pulp-and-paper-production, to due-to-its adequate-fiber dimension, derived fiber value and basic density. Therefore, attention should be given to tree growers, government and non-governmental organizations on the plantation expansion of Acacia melanoxylon.

Flexural bearing capacity of reinforced concrete beams reinforced with carbon fiber reinforced plastics strips and ultra-high performance concrete layers

PurposeTo make full use of the tensile strength of near surface mounting (NSM) pasted carbon fiber reinforced plastics (CFRP) strips and further increase the flexural bearing capacity and flexibility of reinforced concrete (RC) beams, a new composite reinforcement method using ultra-high performance concrete (UHPC) layer in the compression zone of RC beams is submitted based on embedding CFRP strips in the tension zone of RC beams. This paper aims to discuss the aforementioned points.Design/methodology/approachThe experimental beam was simulated by ABAQUS, and compared with the experimental results, the validity of the finite element model was verified. On this basis, the reinforced RC beam is used as the control beam, and parameters such as the CFRP strip number, UHPC layer thickness, steel bar ratio and concrete strength are studied through the verified model. In addition, the numerical calculation results of yield strength, ultimate strength, failure deflection and flexibility are also given.FindingsThe flexural bearing capacity of RC beams supported by the new method is 132.3% higher than that of unreinforced beams, and 7.8% higher than that of RC beams supported only with CFRP strips. The deflection flexibility coefficient of the new reinforced RC beam is 8.06, which is higher than that of the unreinforced beam and the reinforced concrete beam with only CFRP strips embedded in the tension zone.Originality/valueIn this paper, a new reinforcement method is submitted, and the effects of various parameters on the ultimate bearing capacity and flexibility of reinforced RC beams are analyzed by the finite element numerical simulation. Finally, the effectiveness of the new method is verified by the analytical formula.

Analytical solutions for circular composite-lined tunnels under obliquely incident seismic SV and P waves

An analytical solution can easily and quickly give the internal forces in tunnels due to seismic waves, by which, the relationship between the key parameters could also be clarified. These methods are widely used in preliminary seismic design of tunnels. This paper presents new analytical solutions for thrust and moment of circular composite-lined tunnels with arbitrary layer linings under obliquely incident SV waves and P waves. Wherein, the lining is regarded as a thick-wall cylinder. Moreover, the proposed analytical solutions can consider different contact conditions of the ground-tunnel and lining-lining interface. The new analytical solutions are verified by comparing with the dynamic finite element analysis results. The results show the accuracy and applicability of the proposed analytical solutions. Parametric analyses are performed to explore the effects of the flexibility coefficient δ, incident angle and steel lining on the seismic response of tunnels.

Steady State and Transient Vibration Analysis of an Exponentially Graded Rotor Bearing System Having a Slant Crack

The dynamic behaviour of a slant-cracked exponentially graded (EG) rotor-bearing system has been investigated using the finite element method for flexural vibrations. A two nodded EG rotor element has been developed based on the Timoshenko beam theory. Local flexibility coefficients (LFCs) of a slant-cracked EG shaft element have been derived using fracture mechanics concepts to develop the stiffness matrix of a cracked EG element. The steady-state and transient vibration responses of cracked and uncracked rotor systems have been simulated using the Houbolt time marching method. When a crack is present in the shaft, the subharmonic frequency peaks are centred on operating speed in the steady-state frequency responses, whereas on critical speed in the transient frequency responses at an interval frequency corresponding to the torsional frequency. It has been found that the crack parameters such as crack depth and location, temperature gradients and torsional frequencies have a significant influence on natural frequencies and dynamic responses, which could be implemented for efficient rotor crack detection methodologies.

Reaction of sunflower varieties and hybrids to weather conditions and their adaptability parameters

In regions with contrasting weather conditions, which include the Saratov region, it is necessary to conduct selection and evaluate breeding material not only in terms of productivity, but also in terms of adaptability to abiotic environmental factors. The experimental part was carried out on the experimental field of the Federal Agricultural Research Center for South-East Region in 2015–2021. There were 10 genotypes in the study, which were evaluated by the ability to form the highest productivity in different years in terms of moisture and heat supply. The HTC in the years of research was as follows: 2015 - 0.61, 2016 - 0.47, 2017 - 0.95, 2018 - 0.52, 2019 - 0.6, 2020 - 0.83, 2021 - 0.58. The coefficient of variation, stress resistance and genetic flexibility, the drought resistance index, and the coefficient of responsiveness to favorable growing conditions were indicators of adaptability. According to long-term data, the average yield of oilseeds of the studied varieties and hybrids varied from 1.98 to 2.54 t/ha. In some years, the yield of varieties Saratovskiy 20, Stepnoy 81, Stepnoy 82, Lyubimchik and hybrid YuVS 7 exceeded 3.0 t/ha. In 9 out of 10 varieties and hybrids, a high variability of the trait is noted (V = 21.7-33.1%). The average yield variability was found in the UVS 3 hybrid (V = 19.1%). Varieties Stepnoy 81, Lyubimchik are characterized by high genetic flexibility ((Ymin + Ymax)/2 = 2.50 and 2.75, respectively) and responsiveness to favorable environmental conditions (Kp = 2.52 and 2.23, respectively). The hybrid YuVS 3 is characterized by high stress resistance (Ymin + Ymax = -1.15) and drought resistance (DSI = 0.92). High genetic flexibility ((Ymin + Ymax)/2 = 2.45) and drought resistance (DSI = 0.98) had SVS 7. It is advisable to include varieties and hybrids with high adaptive properties in the further breeding process as initial material.

2D Transition Metal Dichalcogenide with Increased Entropy for Piezoelectric Electronics.

Piezoelectricity in 2D transition metal dichalcogenides (TMDs) has attracted considerable interest because of their excellent flexibility and high piezoelectric coefficient compared to conventional piezoelectric bulk materials. However, the ability to regulate the piezoelectric properties is limited because the entropy is constant for certain binary TMDs other than multielement ones. Herein, in order to increase the entropy, a ternary TMDs alloy, Mo1- x Wx S2 , with different W concentrations, is synthesized. The W concentration in the Mo1- x Wx S2 alloy can be controlled precisely in the low-supersaturation synthesis and the entropy can be tuned accordingly. The Mo0.46 W0.54 S2 alloy (x= 0.54) has the highest configurational entropy and best piezoelectric properties, such as a piezoelectric coefficient of 4.22 pm V-1 and a piezoelectric output current of 150 pA at 0.24% strain. More importantly, it can be combined into a larger package to increase the output current to 600 pA to cater to self-powered applications. Combining with excellent mechanical durability, a mechanical sensor based on the Mo0.46 W0.54 S2 alloy is demonstrated for real-time health monitoring.

Elastodynamic analyses of transversely isotropic unsaturated subgrade–pavement system under moving loads

AbstractIn this paper, elastodynamic responses of the layered transversely isotropic unsaturated subgrade–pavement system subjected to the moving load are investigated. The unsaturated subgrade soil is described via a triphasic Biot‐type model introducing the effect of matric suction, immiscible flows of water and air, and transverse isotropy. The rigid pavement is modeled by the Kirchhoff plate theory, while the flexible pavement is modeled by the stratification medium theory. First, the governing equations of the unsaturated subgrade soil are obtained after algebraical manipulations. The precise integration method (PIM) is further combined with the double Fourier transform to solve the governing equations. The subgrade soil solution is utilized as the flexible coefficient to describe the plate–soil interaction, and the solution of the pavement is further acquired via the double inverse Fourier transform. Four verification examples regarding literatures and COMSOL are presented to verify the correctness of the theory. Finally, numerical examples are conducted to investigate the effect of various parameters on the dynamic behavior of the unsaturated subgrade–pavement system.

On the Performance of Nonlinear Corrective Active Constellation Expansion in OTFS Systems

Orthogonal time frequency space (OTFS) modulation has been put forward to achieve better performances over delay-Doppler channels in comparison with orthogonal frequency division multiplexing (OFDM) systems. In this letter, a nonlinear corrective active constellation expansion (NC-ACE) method is firstly proposed in OTFS waveform to achieve precise control of peak-to-average power ratio (PAPR) and BER performances due to its nonlinear compression characteristics. Compared to linear constraint of clipping and filtering process in traditional active constellation expansion (ACE) and bounded distortion ACE (BD-ACE) strategies, nonlinear compressed clipping noise is considered with a flexible curvature control coefficient. According to flexible features of NC-ACE, a bridge between optimal suppression and no reduction of PAPR performances is established in OTFS systems, where tradeoff between PAPR and BER performances can be further obtained.

Результаты экологического испытания сортов ярового ячменя в южной лесостепи Южного Урала

Abstract. The aim of the research was to adjust the direction of barley breeding towards the creation of semi-intensive and intensive varieties, for farms with different levels of agricultural culture, according to economically valuable characteristics adapted to the conditions of the Chelyabinsk region. An assessment of the ecological testing of spring barley varieties in the southern forest-steppe zone of the Southern Urals during sowing according to the fallow and grain predecessor for 2018 – 2020 of the parameters of ecological adaptability in yield was carried out. Methods. The studies were conducted from 2018 to 2020. In the conditions of the southern forest-steppe of the Chelyabinsk region, GP “Troitskoe”. A detailed analysis of the adaptability parameters is given: the coefficients of the environmental conditions index (Ij), the coefficients of adaptation, genetic flexibility, plasticity (bi) and stability (2d) are calculated. The selection of varieties for all studied parameters was obtained. Results. The results of this environmental test showed that of the whole set, the varieties have high ecological plasticity for this period: Omsk 95, Orda, Nutans 236C158, Nutans 272F677, Nutans 193C93 with an adaptability coefficient greater than 1. Nutans 236C158, Orda, Nutans 272F677, Nutans193C93 showed the maximum adaptability for 3 years when sowing according to the grain predecessor, they had a consistently high yield and an adaptation coefficient greater than 1 under any weather conditions. An increase in the genetic flexibility of varieties was found when sowing in pairs from 1.61 to 3.09. For the zone of risky farming, the most plastic varieties with a high yield potential in any weather conditions were distinguished: Orda, Nutans 236C158, Nutans 272F677, Omsk 95, Nutans 193C93 and Nutans 207C74. Pallidum 297C151, Chelyabinsk 99, Chelyabinsk 96 and Nutans 103G177 varieties reacted sharply to changes in vegetation conditions. Scientific novelty Groups of the studied varieties have been identified according to the parameters of ecological plasticity and stability, simplifying selection for further breeding process. Varieties Omsk 99 and Vakula can be used for breeding for drought resistance.

Vibrational energy estimation of cracked composite beams using radiative energy transfer method

An energy flow model based on the radiative energy transfer method (RETM) is established for the high-frequency response prediction of finite composite beams with edge cracks. The Timoshenko beam theory is applied to derive the motion governing equations of the beam. The composite beam is divided into several components in line with its multiple cracks. Cracks and boundary conditions are modeled as elastic springs. Spring stiffnesses at the cracks are obtained by the inverse of the flexibility coefficients from the fracture mechanics theory. Power reflection and transmission coefficients through the cracks are derived through wave propagation analysis. The response of the beam loaded by a high-frequency point force is described by vibrational energy density and intensity. The energy response of each part of the beam is contributed by the rays emitted from the actual source set at load point and then, reflected or transmitted through the fictitious sources at cracks. Fictitious sources are determined by the energy balance equations at cracks and boundaries. Numerical examples show that the energy distributions of the multi-cracked composite beams are well predicted by the proposed approach.

Wood cells characterization and suitability appraisal of 7- and 9-year-old Cedrela odorata L. (Miliaceae) wood for paper-based products manufacturing

ABSTRACT This study sought to appraise 7-year and 9-year-old Cedrela odorata for pulp and paper making. Sectioning and maceration processes were adopted. Data were subjected to statistical analysis using SPSS version 17.00. Cell characteristics for all ages and tree positions appeared similar but quantitatively, cells in 9-year-old generally exhibited some significant (p < .05) variations. Age and wood position generally had some significant influence on cell characteristics. Fibre lengths were generally short (<1.6 mm or 1600 μm) with variations in fibre morphology being significant axially than radially. In appraising the wood for paper production, derived fibre indices/values viz; Runkel ratio (ranging from 0.19 to 0.28), flexibility coefficient (ranging from 0.78 to 0.83), and slenderness ratio (ranging from 38.98 to 51.72) appeared to provide some positive indications. The species therefore, has potential for pulp and paper production, but further studies on its chemical consumption levels and other properties need to be ascertained towards a well-informed decision.

Characterization and Construction of Generalized Bent Functions with Flexible Coefficients

Characterization and Construction of Generalized Bent Functions with Flexible Coefficients