Shaft Diameter Research Articles

Chemical body composition and bone growth of young pigs as affected by deficiency, adequate and excess of dietary phosphorus supply

Abstract Objective of the experiment was to study the effect of deficiency, adequate and excess dietary phosphorus supply on growth performance, retention and utilisation of phosphorus, length, mass and geometry measurements of the femur shaft, content of protein, ash, phosphorus in viscera, edible (meat and fat) and inedible (bones and skin) parts of the body in pigs ageing from 33 to 110 days. It was found that compared to animals fed according to phosphorus requirement the deficiency and excess of dietary phosphorus did not influenced o total feed intake (mean 120.6 kg) and feed conversion (mean 1.9 kg/kg gain). However phosphorus deficiency lowered total gain of the body mass (P=0.0072), diminished weight of the inedible part of the carcass (P=0.0229), decreased the content of body protein (P=0.0171), ash (P=0.0001), and phosphorus (P=0.0001). Whereas, over-supply of dietary phosphorus did not cause any change of these component. Utilisation of the total phosphorus was diminished (P=0.0001) in pigs fed diet with both excess (by 16.26%) and deficiency (by 12.28%) of the phosphorus, but excess had much lower negative impact than its’ deficiency. When available form of this element was considered over-supply still reduced (P=0.0001) its utilisation the most (by 26.58%) but deficiency made utilisation the best (7.77%). Both dietary deficiency and over-supply of the phosphorus diminished (P=0.0001) femur mass (by 25 and 11 g, respectively). Thus negative impact of phosphorus deficiency was much stronger. Moreover, phosphorus deficiency diminished (P=0.0015) bone length (by 0.5 cm), however, excess did not change this feature. Response of animals to a decrease bone mass and length due disturbances in phosphorus supply (both deficiency and excess) was the increase the vertical external diameter of the femur shaft.

Role of dissipation chamber in energy loss of vortex structures: Experimental evaluation

In this research, the flow energy dissipation efficiency in the dissipation chamber section has been studied by constructing a physical model with a scale of 1:10. In this regard, with the aid of dimensional analysis, the influential factors affecting the performance of the flow energy loss in dissipation chamber were Froude number, ratio of drop total height to shaft diameter, and ratio of sump depth to shaft diameter. Then, 144 experiments were performed by a full factorial experiment design in way that 4,3, and 3 levels were considered for Froude number, ratio of drop total height to shaft diameter, and ratio of sump depth to shaft diameter. Additionally, four replications for all possible combinations of effective factors have been included. The minimum and maximum of flow energy dissipation efficiency values were measured 73.9% and 88.3%, respectively. Moreover, in order to maximize flow energy dissipation efficiency, the optimal values of three contributing factors (i.e., Froude number, the ratio of drop total height to shaft diameter, and ratio of sump depth to shaft diameter) obtained 2.32, 13.901, and 1.467, respectively. A regression based equation in form of a quadratic polynomial was proposed to estimate the value of flow energy dissipation efficiency with the coefficient of determination of 0.7196. Generally, the measured flow energy dissipation efficiency changed from 73.90 to 88.30%

Estimation of the Uplift Resistance for an Under-Reamed Pile in Dry Sand Using Machine Learning

Abstract Under-reamed piles are extensively used to resist uplift forces and settlements. The objective of the present study is to develop various machine learning models (linear and non-linear) and determine the best model to estimate the ultimate uplift resistance of under-reamed piles embedded in cohesionless soil. The machine learning models were developed considering the following input parameters: the density index, dry density, base diameter, angle of an enlarged base with a vertical axis, shaft diameter, and embedment ratio. A linear equation is proposed to estimate the ultimate uplift resistance based on Multivariate Linear Regression analysis with a mean absolute error equaling 0.25kN and 0.50kN for loose and dense sands respectively. The Decision Tree Regression model provides an excellent degree of accuracy with a mean absolute error of 0.02kN and 0.02kN in cases of loose and dense sands respectively.

A Clinico-Trichoscopic Analysis of Hair Density and Diameter Variability in Relation to Severity Grading of Female Pattern Hair Loss

Hair loss is a common complaint among Indian women. For female pattern hair loss (FPHL), diagnosis is primarily clinical. In the early stages, it can be confused with other conditions. Histopathology is the diagnostic method of choice but requires multiple biopsies and can be disfiguring. Trichoscopy is an alternative noninvasive, rapid tool. The aim of this study is to study the hair density and hair diameter variance in relation with severity grading of FPHL. Cross-sectional study. Ninety women aged 18 years and above were included in this cross-sectional study conducted at the dermatology department of Bangalore Medical College and Research Institute. Trichoscopic examination was done with a videodermoscope (Firefly DE300) at 20 and 70-fold magnification. Only those patients who met the trichoscopic diagnostic criteria for FPHL were included. Descriptive statistics, ANOVA, and Spearman's correlation test for fitness of good, using Microsoft Excel data analysis tools. Increase in disease severity from grade one to grade three positively correlated with a decrease in hair density over the frontal scalp (P < 0.001) and the occipital scalp (P < 0.001), decrease in average hair shaft diameter over both frontal and occipital scalp (P < 0.001). Trichoscopic tools, particularly hair density and hair diameter variance over both frontal and occipital scalp can be useful to help determine FPHL disease severity and its progression.

A Handheld Steerable Surgical Drill With a Novel Miniaturized Articulated Joint Module for Dexterous Confined-Space Bone Work.

Steerable surgical drills have the potential to minimize intraoperative tissue damage to patients. However, due to their large shaft diameters, large bend radii, and small bend angles, existing steerable drills are unsuitable for dexterous operations in confined spaces. This article presents a handheld steerable drill with a ϕ4.5-mm miniaturized tip, capable of abruptly bending up to ±65°. To achieve a small tip diameter and a large bend angle, we propose a novel articulated joint module composed of a tendon-driven geared rolling joint and a double universal joint for steering the drill shaft and transmitting drilling torques, respectively. We integrate this joint module with a customized compact actuation unit into a handheld device. The integrated handheld steerable drill is slim and lightweight, supporting burdenless, single-handed grips and easy integration into existing surgical procedures. Experiments and analysis showed the proposed steerable drill has high distal dexterity and is capable to remove target tissues dexterously through a small passage/incision with minimized collateral damage. The results suggest the potential of the proposed miniaturized articulated drill for dexterous bone work in confined spaces. By enhancing distal dexterity and reach for surgeons when dealing with hard bony tissues, the proposed device can potentially minimize surgical invasiveness and thus collateral tissue damage to patients for a better clinical outcome.

PERANCANGAN MODIFIKASI MESIN BENDING ROTARY BAJA APLIKASI STAND POT BUNGA

Plants grown in pots continue to grow year after year. A flower pot support or flower pot stand is required to add aesthetic value and save space. The purpose of this research is to develop a steel rotary bending machine design for flower pot stand applications The method used is to calculate the rotational speed of the bending mall, design the transmission, calculate the power and capacity of the machine, calculate and analyze the frame strength, and produce machine design results. The design produces a mall bending rotation of 4.5 rpm with diameters of 100 mm, 120 mm, and 150 mm, an electric motor with a rotation speed of 2840 rpm and a power of 1 HP, 4 pulleys and 2 types A V-belts, a shaft diameter of 20 mm and a 6 x 6 mm key, UCP and UCF type bearings, conical gears with a reduction of 10:16, a gearbox with a reduction of 1:40. The required power is 146 watt (0,2 horsepower), and the engine capacity is 243 bends per hour. The engine frame has dimensions of 750 x 550 x 1000 mm and is made of AISI 1045 material. The highest stress that occurs in the frame is 45.55 N/mm2.

전기자동차 스플라인 품질과 축 불균형에 의한 충격성 소음 개선에 대한 연구

Impact noise generated in electric vehicles in the 200 Hz ~ 500 Hz is perceived as rumble noise of an internal combustion engine. It is one of the biggest noise problems during electric vehicle development. This noise is caused by a shock phenomenon generated in each revolution due to interference between the minor diameter of the motor shaft spline and the reducer input shaft spline due to misalignment. Through spline measurement comparisons and spline LDP analysis results, the minor diameter of the motor shaft and its misalignment have proved to be important factors. To eliminate spline impact noise and maintain the spline

Research on a Large Diameter Magnetic Fluid Seal With Thin-Wall Parts

Magnetic fluid seal is a new type of sealing method, which has been applied in many fields. For some fields, such as aviation and aerospace, high sealing performance, large shaft diameter, and small design space are required, which brings difficulties to the sealing design. Therefore, it is necessary to study a large diameter magnetic fluid seal with thin-wall parts. In this article, the effects of seal clearance and shaft deflection on the magnetic field distribution of magnetic fluid seal are analyzed by the finite element method. At the same time, the force of seal shaft in the assembly process is also simulated. The influence of the amount of magnetic fluid on the pressure resistance is analyzed. The low-temperature starting torque and high-temperature pressure resistance of magnetic fluid seal are experimentally studied, and the optimal injection amount of magnetic fluid is obtained. The research content of this article can be used as a reference for the design of a large diameter magnetic fluid seal with thin-wall parts.

Numerical study on the performance of swirl tube based on orthogonal design

• Swirl tube has four circumferentially symmetric blades with 180° twist angle. • Axial distance between the diffuser and blade for performance was assessed. • Structure of the swirl tube was optimized with orthogonal table. Here, an axial flow cyclone separator is design is proposed. The effects of varying the structural parameters and operating conditions on pressure drops and separation efficiency were investigated via a numerical simulation approach. The results show that of the three structural parameters considered, the distance between the diffuser and blade is the most significant factor impacting separation performance compared to the blade pitch and blade shaft diameter. Increasing the distance between conical outlet and blade can decrease its pressure drops and increase separation efficiency; while increasing the shaft diameter can increase pressure drops, and the increasing blade pitch can decrease both the pressure drop and the separation efficiency. The pressure drop of the optimized swirl tube was 102.1 Pa, with a corresponding separation efficiency of 95.04% for 100 μm particles at an extraction ratio of 10%. Further, the cut-off particle size can reach 3 μm, demonstrating that the swirl tube offers good separation performance and has the potential to be widely applied in industrial gas–solid separation applications.

Perancangan Mesin Pencuci Karpet Menggunakan Tabung Cairan Deterjen

Carpet washer is a machine that is used to help complete work in the laundry industry. By using this carpet cleaning machine, cleaning carpets is fast and easy. The purpose of designing this carpet washing machine is a form of innovation and creativity based on technological developments. This machine is made with an additional tube of liquid detergent to make work easier and increase efficiency. The initial method of designing this carpet washing machine is to collect data. Next is the calculation and design. The results of the design of this carpet washing machine obtained a motor power of 1.5 HP and a rotation of 1400 rpm, with a height of 1020 mm, a length of 745 mm and a width of 345 mm using a type-A belt transmission, pulleys with a diameter of 2” and 6”, a shaft diameter of 19 mm, the type of bearing used is UCF F212 type, has a cleaning brush and uses a liquid detergent tube. The design of this carpet washing machine has been made based on the correct design and calculation and can be continued for production.

Midshaft diameter of humerus and its accuracy in sex determination of south Indian population

Background: Humerus is one of the long bones generally favoured in osteometric studies as it appears to yield highest level of classification accuracy in sex determination. Aim: To study the midshaft diameter of humerus and its accuracy factor in sex determination. Methods: A total of 100 (Male - 72, Female - 28) dry human humeri were collected from the Department of Anatomy as well as from the under graduate students of Santhiram Medical College, Nandyal. The maximum midshaft diameter of humerus was measured from absolute greatest diameter without regard to the vertical or transverse plane. The minimum midshaft diameter of humerus was measured from absolute least diameter in the middle without regard to any plane or maximum diameter Results: The mean maximum mid shaft diameter of humerus in male bones was 1.953±0.027 and in female bones was 1.75±0.030. The mean minimum midshaft diameter of humerus in male was 1.657±0.0211 and in female was 1.485±0.026 in the present study Conclusion: The mid shaft diameter can be considered as one of the sex determinations factors due to its higher accuracy in males than females with other predictive variables of humerus.

Midshaft diameter of humerus and its accuracy in sex determination of south Indian population

Background: Humerus is one of the long bones generally favoured in osteometric studies as it appears to yield highest level of classification accuracy in sex determination. Aim: To study the midshaft diameter of humerus and its accuracy factor in sex determination. Methods: A total of 100 (Male - 72, Female - 28) dry human humeri were collected from the Department of Anatomy as well as from the under graduate students of Santhiram Medical College, Nandyal. The maximum midshaft diameter of humerus was measured from absolute greatest diameter without regard to the vertical or transverse plane. The minimum midshaft diameter of humerus was measured from absolute least diameter in the middle without regard to any plane or maximum diameter Results: The mean maximum mid shaft diameter of humerus in male bones was 1.953±0.027 and in female bones was 1.75±0.030. The mean minimum midshaft diameter of humerus in male was 1.657±0.0211 and in female was 1.485±0.026 in the present study Conclusion: The mid shaft diameter can be considered as one of the sex determinations factors due to its higher accuracy in males than females with other predictive variables of humerus.

A Novel Production Method of Polymer Bolts and the Effects of the Printing Orientation on Tensile and Shear Strength of the 3D Printed Bolts

Lightweight structures are one of the most studied topics today. Many metal machine elements can be produced from lightweight polymer materials with 3D printer technology. In this study a novel manufacturing method is proposed for the polymer bolts and the effects of the printing directions on the tensile and shear strength are investigated experimentally. Firstly the bolt shafts are produced FDM method by using 3D printer for different print orientations and the final diameters of the bolt shafts are determined by the turning process. A special apparatus is designed and manufacture for threader tool. The screw pitches are opened by using this special apparatus with threader tool. After the manufacturing process, the performance of the produced tensile and shear test samples are defined by using tensile and shear tests. A special tensile test apparatus is also developed in this study. It is seen that the printing orientation has great effects on the tensile and shear durability of the bolts. It has been determined that the strength of the bolts produced with a production angle of 0º is the highest, and the strength of the bolts produced with 45º is the lowest.

Design, Fabrication and Testing of a Direct Drive Electric Powered Hammer Mill Machine

This research designed, fabricated and tested a direct drive electric powered hammer mill machine. A 3 HP electric motor with speed of 1800 rpm was used to power the mill. The fundamentals of machine design, mechanics of machine and basic workshop technology were applied in manufacturing the mill. The calculated design values for maximum centrifugal force of the beaters mounted on the rotor and the maximum machine shaft diameter of the mill are 27 KN and 12 mm respectively. The working principle of the mill is based on repeated combined hammers (beaters) impacts and collisions of the materials being milled with the housing of the milling compartment. Tests were carried out on the mill using dry maize, dry millet, dry stock fish and the combination of dry maize, dry millet and dry stock fish as samples to determine the mill productivity and milling efficiency. In determining the productivity and milling efficiency of the mill, the initial masses of the samples were made equal. The dry stock fish sample produced the highest mill productivity and milling efficiency. The actual mill productivity of 45.05 kg/h and milling efficiency of 91.12 % were obtained by averaging the mill productivities and milling efficiencies obtained when the samples were tested. From the calculated values of the actual mill productivity and milling efficiency, the mill performance is satisfactory.

Substantiation of the Parameters for the Grinder of Mineral Fertilizers in the Chisel­Cultivator Hopper

The problem of increasing the irrigated lands productivity and ensuring sufficient reserves of minerals and nutrients for plants is noted to be important in the Republic of Uzbekistan. In practice, when preparing land for sowing cotton, wheat, soybeans and other crops, the application of mineral fertilizers is provided with the help of a chisel cultivator that has two separate hoppers for mineral fertilizers with a capacity of 50 kilograms each. It was revealed that large lumps of caked fertilizers remain in the hoppers, which reduces the productivity and quality of the unit. It was recommended to use an improved device with one container and special grinders for mineral fertilizers installed there.Research purpose To substantiate the parameters for the grinder of large lumps of mineral fertilizers in the chisel-cultivator hopper.Materials and methods The study was focused on the parameters and performance of a mineral fertilizer grinder operating by means of a rotation provided by the unit support wheel.Results and discussion The parameters of the chisel-cultivator were determined for grinding and applying mineral fertilizers at the stage of preparing the soil for sowing.Conclusions A unit with grinding working bodies was developed to install in a chisel-cultivator hopper. The following parameters were specified: the shaft diameter is 40 millimeters, the toothed bar height is 25-30 millimeters, the width is 8–10 millimeters, and the thickness is 2-3 millimeters. In total, 18 bars were fixed in one compartment of the hopper, and 180 pieces in 10 compartments. The selected parameters of the mineral fertilizer grinder in the hopper with a capacity of 350 kilograms facilitate the application of up to 300 kilograms per hectare.

Development of a fatigue strength testing machine

A profound engineering design and modeling of fatigue strength machine for testing the failure which occurs when a metallic material is subjected to cyclic stresses is presented. The main goal is developing a locally made fatigue strength machine that can be used in material science laboratory. A major direction in this development of the machine is the ability to thread on the path of technology transfer and dominance by concentrating on the building of indigenous capacity. In carrying out the machine development, engineering design formulae were applied and Computer Aided Design modeling was developed. The developed fatigue strength testing machine had a designed machine capacity of 18875Nmm that sustained a motor power of 5.93kw.The machine shaft diameter determined to be 9.88mm developed an equivalent torque and bending moment of 45799.8Nmm and 40890Nmm respectively. The machine designed critical speed of 23.52rad/s had belt tensions on the tight and slack sides to be 139.02N and 44.65N respectively. The fabricated machine has the ability to record low and high fatigue cycles.

Oral minoxidil for the treatment of late alopecia in cancer survivors.

12022 Background: Late alopecia is defined as incomplete hair regrowth &gt; 6 months following cytotoxic chemotherapy or from initiation of endocrine therapy. It has been reported in up to 25-30% of cancer survivors and is associated with decreased quality of life and reduced dose intensity of cancer therapies. Minoxidil is an aminopyridine potassium channel opener, resulting in vasodilation and premature entry of resting hair follicles into the anagen (growth) phase and increase in hair follicle size. This study aims to assess clinical outcomes and adverse events of oral minoxidil for the treatment of cancer therapy-related late alopecia. Methods: We retrospectively assessed all women with late alopecia treated with oral minoxidil (1.25 mg daily) evaluated at an oncodermatology referral program between 1/2018-5/2021. Outcomes were assessed by standardized photography (4 views) and trichoscopy (HairMetrix, Canfield Scientific, Inc.). Trichoscopy recorded hair density (hair count/cm2) and hair thickness (shaft diameter) at uniform frontal and occipital target areas (12 and 36 cm midline from the glabella, respectively). Adverse events were recorded and graded using CTCAE v5.0. Descriptive statistics were used to summarize the patient demographics and clinical characteristics. Changes in trichoscopy measurements from baseline to follow-up were estimated using paired t-tests. Results: Two hundred and sixteen patients (mean age 57.8±13.7) were included for analysis. Thirty-one (14%) received chemotherapy alone, 65 (30%) endocrine monotherapy, and 120 (56%) chemotherapy followed by endocrine therapy. The majority of patients (n = 170, 79.1%) had a history of breast cancer. Standardized photography assessments (n = 119) after a median of 105 days (IQR = 70) on oral minoxidil revealed clinical improvement in 88 (74%). Trichoscopy assessments (n = 42) after a median of 91 days (IQR = 126) demonstrated increased frontal hair density (124.2 vs 153.2 hairs/cm2, p = 0.008) and occipital hair density (100.3 vs 123.5 hairs/cm2, p = 0.004). There was no statistically significant difference in average frontal or occipital hair thickness (69.3 vs 67.3 μm, p = 0.22, and 70.3 vs 69.9 μm, p = 0.84, respectively). No patients reported discontinuation of oral minoxidil due to adverse effects. Conclusions: Oral minoxidil may benefit both frontal and occipital late alopecia in cancer survivors treated with cytotoxic and/or endocrine therapy. This regimen was well tolerated by patients. Prospective, controlled studies are needed to confirm these observations.

Mechanical projects: dimensioning of shafts with correction for keyway and bearing support

This article goes through several steps in order to deliver a reliable result, according to the ASME method, of a shaft dimensioning, aiming to automate the calculation memorial process for shaft projects. The design steps are: stress diagrams, fatigue and geometry analysis (if necessary); correction due to discontinuity (if any); shaft diameter correction due to keyway (if any); and correction due to manufacturer’s selected bearing support (adopting SKF models). In this way, the article aims, in order to comply with the literature and standards, to dimension transmission shafts. The results of the exercises solved in the book Projeto de Máquinas: Uma abordagem integrada will be used as a reference. The developed program aims to meet both professional and academic demands by optimizing the calculations to obtain the diameter of a shaft. In addition, the project is justified by the fact that it allows several changes for a better understanding, either for a designer or for a student. The software used to automate the processes and obtain the results will be Mathcad Prime 5.0 from PTC Enterprise. At the end of the article, along with the results and conclusion, there are examples of design problems solved by the program, along with their explanations and comparisons with the results obtained in the Norton’s book.

DESIGN AND SIMULATION OF A PICO HYDROELECTRIC TURBINE SYSTEM

Hydroelectric power is both an efficient and reliable form of a clean source of renewable energy. It can be an excellent method of harnessing renewable energy from small rivers and streams. A Pico hydroelectric power system of a cross-flow turbine type is designed and simulated in this study. Model parameters such as runner diameter, runner length, blade spacing, radius of blade curvature, shaft diameter, water jet thickness, turbine speed, turbine power and the number of blades that play major role to achieve the turbine maximum efficiency were determined theoretically. The designed Hydro-electric power system’s maximum efficiency was estimated to be 87% with a head of 6390 mm at a flow rate of 0.089 . Numerically, analysis of the designed power generation system was carried out using (structural analysis and design) STAAD pro connect software and ANSYS tool. The performance evaluation results using the STAAD pro software for the system water reservoir sitting stanchion simulation indicated that the stanchion will not fail while carrying the load. Similarly, the numerical analysis of the designed cross-flow turbine type in this work using the ANSYS tool revealed that the shaft will be able to withstand deformation due to torsion when subjected to a maximum torque of 51.46 Nm. Hence the designed hydroelectric power system will be efficient to produce a 5kVA electrical power

Generalized Breathing Functions for Stiffness Model of Transversely Cracked Hollow Shaft

The exact breathing mechanism of the transverse crack in the hollow shaft that appears due to the shaft weight is important to analyze correctly the dynamic behavior of the rotor system. We discuss a breathing phenomenon which appears only in the hollow shaft rotation and determine the exact time-varying area moments of inertia for the cracked element cross-section. Considering the variation behavior of the area moments of inertia, generalized breathing functions are suggested to formulate the finite-element stiffness matrix of the crack element. The harmonic balance method (HBM) is employed to solve the finite-element model of the rotor-bearing-disk system. We study the influence of ratio of the internal and external diameter of shaft, dimensionless crack depth, location of crack and angle between the crack and imbalance directions. Some significant behaviors of the system are compared with some previously published results, and they can be contributed to detecting the crack in hollow shaft early. Comparison shows the generalized breathing functions are accurate to model the stiffness variation of shaft due to the crack.