Base Plate Research Articles

Biomineralization in Barnacle Base Plate in Association with Adhesive Cement Protein.

Barnacles strongly attach to various underwater substrates by depositing and curing a proteinaceous cement that forms a permanent adhesive layer. The protein MrCP20 present within the calcareous base plate of the acorn barnacle Megabalanus rosa (M.rosa) was investigated for its role in regulating biomineralization and growth of the barnacle base plate, as well as the influence of the mineral on the protein structure and corresponding functional role. Calcium carbonate (CaCO3) growth on gold surfaces modified by 11-mercaptoundecanoic acid (MUA/Au) with or without the protein was followed using quartz crystal microbalance with dissipation monitoring (QCM-D), and the grown crystal polymorph was identified by Raman spectroscopy. It is found that MrCP20 either in solution or on the surface affects the kinetics of nucleation and growth of crystals and stabilizes the metastable vaterite polymorph of CaCO3. A comparative study of mass uptake calculated by applying the Sauerbrey equation to the QCM-D data and quantitative X-ray photoelectron spectroscopy determined that the final surface density of the crystals as well as the crystallization kinetics are influenced by MrCP20. In addition, polarization modulation infrared reflection-absorption spectroscopy of MrCP20 established that, during crystal growth, the content of β-sheet structures in MrCP20 increases, in line with the formation of amyloid-like fibrils. The results provide insights into the molecular mechanisms by which MrCP20 regulates the biomineralization of the barnacle base plate, while favoring fibril formation, which is advantageous for other functional roles such as adhesion and cohesion.

Effect of Material Change on Stirnol Engine: A Combination of NiTiNOL (Shape Memory Alloy) and Gamma Stirling Engine.

Population explosion, industrialization, and urbanization have accelerated energy requirements across the globe. This has led to the human quest to find simple and cost-effective energy solutions. A promising solution is the revival of the Stirling engine with the addition of Shape Memory Alloy NiTiNOL in it. The experimental results reveal that the addition of a NiTiNOL spring at the base plate of the Stirling engine enhances the overall efficiency of the engine, demonstrating some impact of the shape memory alloy toward the performance output of the Stirling engine. The newly modified engine has been named the STIRNOL ENGINE. The comparative study of Stirling and Stirnol engines reveals a minuscule efficiency improvement, yet there is a furtherance that opens a window for future researchers to get a lead and venture into this new field. We are confident that with more complex designs and better Stirling and NiTiNOL combinations, more efficient engines can be invented in the future. This research focuses on changing the material of the base plate of the Stirnol engine and ascertaining its performance differential through the integration of the NiTiNOL spring. A minimum of four types of materials are utilized for experimentation.

Proterozoic fold and thrust belt imaged on reflection seismic in Arabian plate basement

Major structures are imaged on 2D reflection seismic data within the Precambrian basement of the western Rub’ Al-Khali of Saudi Arabia for the first time. In this area the base-Cambrian Angudan Unconformity that defines top basement is at a depth of 1–2 km with a gentle easterly dip. Large antiformal structures are clear on 2D reflection seismic within the basement. The antiforms are separated by zones that are interpreted as low-angle faults. No basal detachment is seen and the faults pass below the base of reflection seismic at a depth of approximately 12 km. Individual folds have dimensions in the order of 20 km wavelength and 2 km amplitude and occur between 3 and 10 km depth. The structural style is interpreted as compressional by comparison with thrust systems and accretionary prisms elsewhere. Regional studies indicate that basement is comprised of a series of north-south trending oceanic Proterozoic terranes that were brought together in the Ediacaran East African Orogeny. Based on current regional tectonic maps the newly-imaged fold belt is on the east margin of the Khida-Abas terrane. Depth conversion shows the thrusts dip at approximately 10° north in the line of section. A novel combination of cross-section to structural trend obliquity estimates combined with matched filtering of potential field data indicate the fold and thrust belt trends 015°-195° with ESE vergence. This compressional belt may be some internal structure of the Khida-Abas terrane, or may be a non-outcropping accretionary prism on the margin of that terrane, or may even represent a set of amalgamated microterranes that do not outcrop along trend. Either way, these observations represent a major, previously undescribed element of this sector of the East African Orogen.

Nonlinear Modeling of Contact Stress Distribution in Thin Plate Substrates Subjected to Aspect Ratio.

The foundation substrate's basal contact stresses are typically thought to have a linear distribution, although the actual form is nonlinear. Basal contact stress in thin plates is experimentally measured using a thin film pressure distribution system. This study examines the nonlinear distribution law of basal contact stresses in thin plates with various aspect ratios under concentrated loading, and it establishes a model for the distribution of contact stresses in thin plates using an exponential function that accounts for aspect ratio coefficients. The outcomes demonstrate that the thin plate's aspect ratio significantly affects how the substrate contact stress is distributed during concentrated loading. The contact stresses in the thin plate's base exhibit significant nonlinearity when the aspect ratio of the test thin plate is greater than 6~8. The aspect ratio coefficient-added exponential function model can better optimize the strength and stiffness calculations of the base substrate and more accurately describe the actual distribution of contact stresses in the base of the thin plate compared to linear and parabolic functions. The correctness of the exponential function model is confirmed by the film pressure distribution measurement system that directly measures the contact stress at the base of the thin plate, providing a more accurate nonlinear load input for the calculation of the internal force of the base thin plate.

Theoretical analysis of the elastic Kelvin-Helmholtz instability in explosive weldings

By considering the joint effects of the Kelvin–Helmholtz (KH) and Rayleigh–Taylor (RT) instabilities, this paper presents an interpretation of the wavy patterns that occur in explosive welding. It is assumed that the elasticity of the material at the interface effectively determines the wavelength, because explosive welding is basically a solid-state welding process. To this end, an analytical model of elastic hydrodynamic instabilities is proposed, and the most unstable mode is selected in the solid phase. Similar approaches have been widely used to study the interfacial behavior of solid metals in high-energy-density physics. By comparing the experimental and theoretical results, it is concluded that thermal softening, which significantly reduces the shear modulus, is necessary and sufficient for successful welding. The thermal softening is verified by theoretical analysis of the increase in temperature due to the impacting and sliding of the flyer and base plates, and some experimental observations are qualitatively validated. In summary, the combined effect of the KH and RT instabilities in solids determines the wavy morphology, and our theoretical results are in good qualitative agreement with experimental and numerical observations.

Total knee arthroplasty in patients with severe obesity: outcomes of standard keeled tibial components versus stemmed universal base plates

BackgroundPatients with severe obesity [body mass index (BMI) ≥ 40 kg/m2] potentially overload the tibial component after total knee arthroplasty (TKA), risking tibial subsidence. Using a cemented single-radius cruciate-retaining TKA design, this study compared the outcomes of two tibial baseplate geometries in patients with BMI ≥ 40 kg/m2: standard keeled (SK) or universal base plate (UBP), which incorporates a stem.MethodsThis was a retrospective, single-centre cohort study with minimum 2 years follow-up of 111 TKA patients with BMI ≥ 40 kg/m2: mean age 62.2 ± 8.0 (44–87) years, mean BMI 44.3 ± 4.6 (40–65.7) kg/m2 and 82 (73.9%) females. Perioperative complications, reoperations, alignment and patient-reported outcomes (PROMS): EQ-5D, Oxford Knee Score (OKS), Visual Analogue Scale (VAS) pain score and satisfaction were collected preoperatively, and at 1 year and final follow-up postoperatively.ResultsMean follow-up was 4.9 years. SK tibial baseplates were performed in 57 and UBP in 54. There were no significant differences in baseline patient characteristics, post-operative alignment, post-operative PROMs, reoperations or revisions between the groups. Three early failures requiring revision occurred: two septic failures in the UBP group and one early tibial loosening in the SK group. Five-year Kaplan–Meier survival for the endpoint mechanical tibial failure was SK 98.1 [94.4–100 95% confidence interval (CI)] and UBP 100% (p = 0.391). Overall varus alignment of the limb (p = 0.005) or the tibial component (p = 0.031) was significantly associated with revision and return to theatre.ConclusionsAt early to mid-term follow-up, no significant differences in outcomes were found between standard and UBP tibial components in patients with BMI ≥ 40 kg/m2. Varus alignment of either tibial component or the limb was associated with revision and return to theatre.

Exploration of making removable partial denture by digital technology

To explore the digital manufacturing process of distal extension removable partial denture. From November 2021 to December 2022, 12 patients (7 males and 5 females) with free-ending situation were selected from the Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University. Three-dimensional model of the relationship between alveolar ridge and jaw position was obtained by intraoral scanning technique. After routine design, manufacturing and try-in of metal framework for removable partial denture, the metal framework was located in the mouth and scanned again to obtain the composite model of dentition, alveolar ridge and metal framework. The free-end modified model is obtained by merging the digital model of free-end alveolar ridge with the virtual model with the metal framework. The three-dimensional model of artificial dentition, and base plate was designed on the free-end modified model, and the resin model were made by digital milling technology. The removable partial denture was made by accurately positioning the artificial dentition and base plate, bonding metal framework with injection resin, grinding and polishing the artificial dentition and resin base. Compared with the design data after clinical trial, the results showed that there was an error of 0.4-1.0 mm and an error of 0.03-0.10 mm in the connection between the resin base of artificial dentition and the connecting rod of the in-place bolt and the connection between artificial dentition and resin base. After denturen delivery, only 2 patients needed grinding adjustment in follow-up visit due to tenderness, and the rest patients did not find any discomfort. The digital fabrication process of removable partial denture used in this study can basically solve the problems of digital fabrication of free-end modified model and assembly of artificial dentition with resin base and metal framework.

REVIEW DESAIN GEDUNG PELAYANAN TERPADU UNIVERSITAS TRIBHUWANA TUNGGADEWI MALANG DENGAN KONSTRUKSI BAJA

The application of engineering in the field of civil engineering is growing rapidly, requiring more productivity, creativity, and innovation from structural engineers, especially in the field of structural engineering. To get the optimal cross-sectional dimensions, the magnitude of the forces or loads acting on the structure needs to be analyzed for beams and columns. Under the influence of the working load, the moment bearing capacity will deform evenly throughout the elements. In a flexible structure, the load acting on each structural element needs to be taken into account the moment of deformation. As a design review material, the Tribhuwana Tunggadewi University Integrated Service Building is an integrated service building consisting of 5 floors, which in its main structure uses steel construction, a design review will be conducted, which aims to determine the strength and reliability of the construction. The results of the Review on the Design of the Integrated Service Building, Tribhuwana Tunggadewi University, Malang, are Column(1) steel using the WF profile. 350 . 175 . 7. 11, safe against moments, shear forces, axial forces and buckling or buckling. Column (2) concrete 30 cm x 60 cm is safe against tensile forces, shear forces and axial forces. Block (1) uses WF. 350 .175 . 7. 11, beam (2) uses WF 200 . 100 .5.5 .8 , block (3) uses WF.400.2000.8.13, block (4) uses WF 250 . 125 . 6.9, to the required cross-sectional height and secondary flexural stresses. The floor slab uses 0.75 mm bond with 10 cm concrete and 10 - 200 cm diameter reinforcement (f) which is safe against moments, shear forces and deflections. Connections using Type A-325 bolts with a diameter of 19, safe against tensile forces, shear forces, and bearing forces. Supports using base plates and anchors are safe against tensile forces, shear forces and axial forces.

Pembinaan Tukang Mengenai Sambungan Baja Pada Bangunan Gedung di Kecamatan Sekarbela Kota Mataram

The availability of land for the residential area is becoming scarce in Mataram, The capital city of West Nusa Tenggara. In response to this situation, the construction of high buildings becoming a trend. A trend that initiating a new quandary as this city is located in a high-risk area, prone to earthquakes. Still fresh in our memory, when this area was struck by a series of earthquakes in 2018, two major shocks of 7 and 6,9 magnitude were followed by thousands of aftershocks. Therefore, means are needed to mitigate the risk, for instance reinforcing the utilization of steel. Steel is known for its capacity to withhold immense quakes. Melted connecting plates and cracked connecting bolts are frequent issues in high building construction, often leading to the faulty building. Hence, educating craftsmen on steel structure connection is essential. This community service is done by training craftsmen after acquiring data regarding their capabilities. On the training day, craftsmen were taught by the community service team regarding frame connection, column beam connection, the connection of sub-beam main beam, and base plate connection. The craftsmen are given time to discuss with the community service team. The evaluation shows, there is an increase in craftsmen performance scores after receiving the training, there was an increase of 44,74 or equivalent to 112,225%.

Impact of in Situ Heat Treatment Effects during Laser‐Based Powder Bed Fusion of 1.3343 High‐Speed Steel with Preheating Temperatures up to 700 °C

For laser‐based powder bed fusion (PBF‐LB) of high carbon steels, preheated build platforms can reduce thermal stresses and crack formation inside the generated material. Furthermore, the heat distribution during PBF‐LB is affected by laser energy input and heat transfer into the surrounding area. Depending on the preheating temperature and the thermal conditions during PBF‐LB, thermal gradients and different thermal exposure times of the manufactured layers can lead to in situ heat treatment effects. As a result, gradients in microstructures and properties are observed in the manufactured material. The effects are investigated on AISI M2 high‐speed steel (1.3343). Specimens are manufactured at platform preheating temperatures between 200 and 700 °C. Base plate and surface temperatures in the building layer are monitored by thermocouples and pyrometry. Local variations in the material microstructure and properties are determined and the effects of temperature distribution on microstructure and hardness are discussed.

Achieving exceptional wear resistance in a crack-free high-carbon tool steel fabricated by laser powder bed fusion without pre-heating

Laser powder bed fusion (LPBF) for the fabrication of dense components used for tooling applications, is highly challenging. Residual stresses, which evolve in the additively manufactured part, are inherent to LPBF processing. An additional stress contribution in high-carbon steels arises from the austenite-to-martensite phase transformation, which may eventually lead to cracking or even delamination. As an alternative to pre-heating the base plate, which is not striven by industry, lowering the martensite content which forms in the part, is essential for the fabrication of dense parts by LPBF of high-carbon tool steels which are then adapted to LPBF. In this study, a successful strategy demonstrates the processing of the Fe85Cr4Mo1V1W8C1 (wt%) high-carbon steel by LPBF into dense parts (99.8%). The hierarchical microstructure consists of austenitic and martensitic grains separated by elemental segregations in which nanoscopic carbide particles form a network. A high density of microsegregation was observed at the molten pool boundary ultimately forming a superstructure. The LPBF-fabricated steel shows a yield strength, ultimate compressive stress, and total strain of 1210 MPa, 3556 MPa, and 27.4%, respectively. The mechanical and wear performance is rated against the industrially employed and highly wear-resistant 1.2379 tool steel taken as the reference. Despite its lower macro-hardness, the LPBF steel (58.6 HRC, 0.0061 mm3 Nm–1) shows a higher wear resistance than the reference steel (62.6 HRC, 0.0078 mm3 Nm–1). This behavior results from the wear-induced formation of martensite in a microscale thick layer directly at the worn surface, as it was proven via high-energy X-ray diffraction mapping.

Visualization study on the flow characteristics of a nitrogen pulsating heat pipe

An experimental setup for visualization study of a nitrogen pulsating heat pipe (PHP) is developed. The PHP is a flat-plate PHP fabricated using MEMS technology with silicon base plate and BF33 glass cover plate. The hydraulic diameter of the channel is 667 μm and the overall dimension of the PHP is 70 × 25 × 2 mm3. The filling ratios (FRs) in this study are measured with visualization images. Six filling ratios are adopted ranging from 15% ∼ 94% and the PHP only fails to start-up with 15% FR. Flow images of nitrogen PHPs are obtained for the first time. Four types of flow patterns are observed. The variations of flow characteristics and fluid motion with heat loads and FRs are analyzed. The fluid motion diagram and flow pattern proportion are extracted from the visualization results as well. Large amplitude oscillating motion is rarely observed in the nitrogen PHP. And annular flow is found to be dominant in low and medium FR working conditions, which indicates the one-dimensional slug flow model may have a narrow application range for the flat-plate nitrogen PHP.

Performance of ANN in Predicting the Tensile and Shear Strength of Al-Steel Explosive Clads

In this study, an artificial neural network (ANN) model is created to predict aluminium-stainless steel explosive clads' tensile and shear strengths. The parameters for the explosive cladding process, such as the loading ratio (mass ratio of the explosive and the flyer, 0.6-1.0), standoff distance (5-9 mm), preset angle (0°-10°), and groove in the base plate (V/Dovetail), were altered. The ANN algorithm was trained in Python using the tensile and shear strengths gathered from 80% of the experiments (60), trials, and prior results. The constructed model was evaluated utilizing the remaining experimental results. The ANN model successfully predicts the tensile and shear strengths with an accuracy of less than 10% deviation from the experimental result.

Design and application of a central venous pressure measurement tool

Central venous pressure (CVP) reflects the comprehensive condition of effective blood volume, cardiac function and vascular tone. Clinical monitoring of CVP can indirectly understand and evaluate the dynamic changes of blood volume in patients, and provide a reference for patients to venous fluid. At present, the traditional manual measurement method is widely used for measurement, which has some shortcomings such as zero shift, cumbersome operation (requires two health care workers to cooperate). In order to overcome the above problems, the author invented a new fixable CVP measurement tool and obtained the national utility model patent (ZL 2021 2 1451705.7). The tool is mainly composed of a base plate, a movable frame and a measuring department, etc. When used, the base plate is placed into the back of the patient and pressed and fixed, the movable frame is adjusted, the zero point is found, and the measurement data is read from the measuring department. It has the advantages of simple and convenient operation, small measurement error, wide applicability (different body types) and so on, which is suitable for clinical promotion.

In the Fast Lane of Technology

Additive manufacturing specialist CA Models optimises base plate removal with new EDM machine; plus, JVD Engineering Ltd acquires a new EDM machine and gains significant benefits

Application of electroplated Ni–Fe thick film to magnetostrictive material in vibration power generator

Ni100−xFex (at. %) films of about 37 μm thickness are electroplated on Cu base plates of 50 mm length, 10 mm width, and 300 μm thickness by varying the composition from x = 0 to 99. They are applied to cantilevers in magnetostrictive vibration power generators. The influences of magnetic and magnetostrictive properties of electroplated film on the vibration power generation property are systematically investigated. The films with x = 41–65 show low coercivities of about 4 Oe reflecting the low magnetocrystalline anisotropy constants. Large negative magnetostriction is recognized for the films with x = 0–14, whereas large positive magnetostriction is observed for the films with x = 57–80. The cantilevers are vibrated at the respective resonance frequencies of about 105–115 Hz and with the acceleration of 1.5 G while applying the bias magnetic field in a range of 0–300 Oe along the length direction. The output voltages are detected by using a coil with 8000 turns. Peak voltages higher than 1 V are obtained for the films with x = 61–65 whose coercivities are low and magnetostrictions are large. The present study has shown that an Ni–Fe film not only with large magnetostriction but also with low magnetic anisotropy constant is useful as the magnetostrictive material in vibration power generator.

Reliability Topology Optimization of Collaborative Design for Complex Products Under Uncertainties Based on the TLBO Algorithm

The topology optimization design of complex products can significantly improve material and power savings, and reduce inertial forces and mechanical vibrations effectively. In this study, a large-tonnage hydraulic press was chosen as a typically complex product to present the optimization method. We propose a new reliability topology optimization method based on the reliability-and-optimization decoupled model and teaching-learning-based optimization (TLBO) algorithm. The supports formed by the plate structure are considered as topology optimization objects, characterized by light weight and stability. The reliability optimization under certain uncertainties and structural topology optimization are processed collaboratively. First, the uncertain parameters in the optimization problem are modified into deterministic parameters using the finite difference method. Then, the complex nesting of the uncertainty reliability analysis and topology optimization are decoupled. Finally, the decoupled model is solved using the TLBO algorithm, which is characterized by few parameters and a fast solution. The TLBO algorithm is improved with an adaptive teaching factor for faster convergence rates in the initial stage and performing finer searches in the later stages. A numerical example of the hydraulic press base plate structure is presented to underline the effectiveness of the proposed method.

Influence of Ship-based Vibration on Characteristics of Arc and Droplet and Morphology in Wire Arc Additive Manufacturing

To explore the feasibility of using wire arc additive manufacturing (WAAM) for forming and repairing marine components during ship navigation, this study conducted deposition experiments of ER50-6 steel and investigated the interference of ship-based vibrations on the WAAM equipment and influence of the characteristics of the arc droplets and sample morphology. The results revealed that the WAAM equipment vibrated with the external vibrations from the surrounding environment, and the welding gun and base plate produced dissimilar vibrations, which yielded unstable arc shapes resembling a bell, trumpet, fan, broom, and other irregular shapes. The mode of the droplet transfer ranged from the stable spray transfer mode to extensive amounts of large droplet transfer and short-circuit transfer. Although the morphology of the obtained sample deteriorated, the fully dense and defect-free interior demonstrated the applicability of ship-based WAAM.

Design and development of hydraulic controlled tractor front mounted twin conveyor onion (Allium cepa) digger

In India and many developing countries harvesting of onion (Allium cepa L.) crop is done manually which is cumbersome and time-consuming. The tractor-operated front-mounted twin conveyor onion digger was designed and developed during 2019 in Divisional Workshop (Farm Machinery and Power Engineering) at Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand. It had five blades made of mild steel (320 mm × 150 mm × 12 mm size) bolted to the base plate instead of one single share to strengthen the share. Onion and soil were separated over conveying unit. Power from the rear PTO (Power take-off) of a tractor to the front-mounted digging unit was conveyed through a power transmission unit which consisted of a gear reduction unit, V-belt and pulley arrangement, and 40 mm diameter of the propeller shaft. The lifting, lowering, and depth were controlled with the help of two single-acting hydraulic cylinders. The biometric and physical properties of onion bulbs (Agri found light red) were found average with equatorial and polar diameter, plant height, neck thickness, and weight of onion dry leaves as 36.19 and 37.19 mm, 284.05 mm, 6.80 mm and 30.19 g respectively. The average soil cone index, moisture content, and bulk density (before transplanting and harvesting) of soil were observed to be 1 kg/cm2, 17.22,12.58%, and 1.50, 1.38 g/cm3 respectively. The performance evaluation in the field found a maximum percentage of exposed and minimum damaged bulbs as 82.55% and 13.51% respectively, at a forwarding speed of 1.5 kmph and conveyor speed of 2 kmph. The field efficiency of the machine was 87.46%.

A Study on the Pressure Mechanism Improvement of a Roller-Type Machine Working Bodies

The parameters of the improved design of the pressure mechanism of a roller technological machine for squeezing wet materials are investigated in this article. The factors influencing the parameters of the pressure mechanism, which provide the required force between the working rolls of a technological machine during the processing of moisture-saturated fibrous materials, such as wet leather, were studied. The processed material is drawn in the vertical direction between the working rolls under their pressure. This study aimed to determine the parameters that make it possible to create the required pressure of the working rolls depending on the change in the thickness of the material being processed. A pressure mechanism of working rolls mounted on levers is proposed. In the design of the proposed device, the length of the levers does not change due to the movement of the sliders when turning the levers; this provides a horizontal direction of the sliders. The change in the pressure force of the working rolls is determined depending on the variation in the nip angle, the coefficient of friction, and other factors. Based on theoretical studies concerning the feed of the semi-finished leather product between the squeezing rolls, graphs were plotted, and conclusions were drawn. An experimental roller stand designated for pressing multi-layer leather semi-finished products has been developed and manufactured. An experiment was carried out to determine the factors affecting the technological process of squeezing excess moisture from wet semi-finished leather products with their multilayer package together with moisture-removing materials by means of their vertical supply on a base plate between rotating squeezing shafts also covered with moisture-removing materials. According to the results of the experiment, the optimal process parameters were selected. It is recommended to carry out the process of squeezing the moisture from two wet semi-finished leather products at a pass rate more than twice as high and with a pressing force of the working shafts two times lower compared to the analog. According to the results of the study, the optimal parameters for the process of squeezing the moisture from two layers of wet leather semi-finished products were chosen, namely the feed rate of 0.34 m/s and a pressing force of the squeezing rollers of 32 kN/m. The use of the proposed roller device allowed an increase of two times or more in the productivity of the process of processing wet leather semi-finished products on the basis of the proposed technique compared to known roller wringers.