Prototype Testing Research Articles

Numerical modelling of global/local mechanisms and sensitivity analysis for the seismic vulnerability assessment of glass curtain walls

Façades represent complex and vulnerable components for buildings, due to the intrinsic fragility and brittleness of glass, and require specific design and calculation tools, both for ordinary and extreme design loads. In this context, the availability of consolidated and strategic modelling strategies is of utmost importance for structural safety considerations and optimal decisions. In this paper, the attention is focused on the assessment of different modelling strategies for the global and local behaviour analysis of Glass Curtain Walls (GCWs) under in-plane seismic loads. Benefits and limitations are discussed for a more refined (but expensive, “MREF”) and a simplified (and computationally efficient, but weak in capturing local phenomena, “MSIMP”) model assemblies developed in ABAQUS and SAP2000, respectively. Careful consideration is given for typical mechanisms, local responses, key performance indicators for the façade components (i.e., stress and deformation peaks) for a reference GCW under monotonic and cyclic loads, as well as for major effects due to general input parameters (i.e., contact mechanisms, clearance, friction, bare frame features, secondary components, etc.), based on a parametric sensitivity investigation. The parametric comparative results are critically discussed, with the support of an experimental prototype test from literature, and the most influencing parameters are emphasized, to improve and facilitate the development of further design and modelling optimization strategies.

Research on DC Electric Shock Protection Method Based on Sliding Curvature Accumulation Quantity

To address the limitations of current DC residual current protection methods, which primarily rely on the amplitude of DC residual current for fault detection and fail to safeguard against electric shocks at two points on the same side in DC Isolated Terra (IT) System systems, this paper introduces a novel protection method based on DC electric shock features. This paper first analyzes the sliding curvature accumulation and peak rise time features of DC basic residual current, load mutation current, and animal body electric shock current under multi-factor conditions. The analysis shows that sliding curvature accumulation in the range of 0.1 ≤ K ≤ 1 and a peak rise time of Δt ≥ 20 ms can effectively distinguish animal body electric shock. Then, based on this electric shock’s distinctive characteristics, an approach for identifying types of electric shock is developed. Finally, a DC residual current protective device (DC-RCD) is designed. The prototype test results demonstrate that the DC-RCD has an action time of ts < 70 ms. The proposed method accurately provides protection against electric shocks and effectively addresses the issue of inadequate protection when two fault points occur on the same side within an IT system. This approach holds significant reference value for the development of next-generation DC-RCDs.

Co-Designing a Smoking Cessation Chatbot: Focus Group Study of End Users and Smoking Cessation Professionals.

Our prototype smoking cessation chatbot, Quin, provides evidence-based, personalized support delivered via a smartphone app to help people quit smoking. We developed Quin using a multiphase program of co-design research, part of which included focus group evaluation of Quin among stakeholders prior to clinical testing. This study aimed to gather and compare feedback on the user experience of the Quin prototype from end users and smoking cessation professionals (SCPs) via a beta testing process to inform ongoing chatbot iterations and refinements. Following active and passive recruitment, we conducted web-based focus groups with SCPs and end users from Queensland, Australia. Participants tested the app for 1-2 weeks prior to focus group discussion and could also log conversation feedback within the app. Focus groups of SCPs were completed first to review the breadth and accuracy of information, and feedback was prioritized and implemented as major updates using Agile processes prior to end user focus groups. We categorized logged in-app feedback using content analysis and thematically analyzed focus group transcripts. In total, 6 focus groups were completed between August 2022 and June 2023; 3 for SCPs (n=9 participants) and 3 for end users (n=7 participants). Four SCPs had previously smoked, and most end users currently smoked cigarettes (n=5), and 2 had quit smoking. The mean duration of focus groups was 58 (SD 10.9; range 46-74) minutes. We identified four major themes from focus group feedback: (1) conversation design, (2) functionality, (3) relationality and anthropomorphism, and (4) role as a smoking cessation support tool. In response to SCPs' feedback, we made two major updates to Quin between cohorts: (1) improvements to conversation flow and (2) addition of the "Moments of Crisis" conversation tree. Participant feedback also informed 17 recommendations for future smoking cessation chatbot developments. Feedback from end users and SCPs highlighted the importance of chatbot functionality, as this underpinned Quin's conversation design and relationality. The ready accessibility of accurate cessation information and impartial support that Quin provided was recognized as a key benefit for end users, the latter of which contributed to a feeling of accountability to the chatbot. Findings will inform the ongoing development of a mature prototype for clinical testing.

Using Physiological Biomarkers to Optimize Management of TBI in Austere Environments.

Multimodal monitoring is the use of data from multiple physiological sensors combined in a way to provide individualized patient management. It is becoming commonplace in the civilian care of traumatic brain-injured patients. We hypothesized we could bring the technology to the battlefield using a noninvasive sensor suite and an artificial intelligence-based patient management guidance system. Working with military medical personnel, we gathered requirements for a hand-held system that would adapt to the rapidly evolving field of neurocritical care. To select the optimal sensors, we developed a method to evaluate both the value of the sensor's measurement in managing brain injury and the burden to deploy that sensor in the battlefield. We called this the Value-Burden Analysis which resulted in a score weighted by the Role of Care. The Value was assessed using 7 criteria, 1 of which was the clinical value as assessed by a consensus of clinicians. The Burden was assessed using 16 factors such as size, weight, and ease of use. We evaluated and scored 17 sensors to test the assessment methodology. In addition, we developed a design for the guidance system, built a prototype, and tested the feasibility. The resulting architecture of the system was modular, requiring the development of an interoperable description of each component including sensors, guideline steps, medications, analytics, resources, and the context of care. A Knowledge Base was created to describe the interactions of the modules. A prototype test set-up demonstrated the feasibility of the system in that simulated physiological inputs would mimic the guidance provided by the current Clinical Practice Guidelines for Traumatic Brain Injury in Prolonged Care (CPG ID:63). The Value-Burden analysis yielded a ranking of sensors as well as sensor metadata useful in the Knowledge Base. We developed a design and tested the feasibility of a system that would allow the use of physiological biomarkers as a management tool in forward care. A key feature is the modular design that allows the system to adapt to changes in sensors, resources, and context as well as to updates in guidelines as they are developed. Continued work consists of further validation of the concept with simulated scenarios.

Performance Improvement of Wireless Power Transfer System for Sustainable EV Charging Using Dead-Time Integrated Pulse Density Modulation Approach

The recent developments in electric vehicle (EV) necessities the requirement of a human intervention free charging system for safe and reliable operation. Wireless power transfer (WPT) technology shows promising options to automate the charging process with user convenience. However, the operation of the WPT system is designed to operate at a high-frequency (HF) range, which requires proper control and modulation technique to improve the performance of power electronic modules. This paper proposes a dead-time (DT) integrated Pulse Density Modulation (PDM) technique to provide better control with minimal voltage and current ripples at the switches. The proposed technique is investigated using a LCC-LCL compensated WPT system, which predominantly affects the high-frequency voltage and current ripples. The performance analysis is studied at different density conditions to explore the impact of the integrated PDM approach. Moreover, the PDM technique gives better control over the power transfer at different levels of load requirement. The simulation and experimental analysis was performed for a 3.7 kW WPT prototype test system under different modes of operation of the high-frequency power converters. Both the simulated and experimental results demonstrate that the proposed PDM technique effectively enhances the efficiency of the HF inverter while significantly reducing output current ripples, power dissipation and improving the overall WPT system efficiency to 92%, and leading to a reduction in the power loss in the range of 10% to 20%. This leads to improved overall system control and performance.

Developing an integrated solid desiccant dehumidifier and dew-point evaporative cooler for green air conditioning

The advancement of eco-friendly air conditioning technology has garnered significant interest in light of energy shortages and concerns regarding global warming. However, current research endeavors have encountered obstacles in addressing issues like chemical erosion and energy-intensive processes. A promising solution to overcome these challenges involves integrating a solid desiccant coated heat exchanger-dehumidifier (SDHED) with a dew-point evaporative cooler (DPEC). This innovative approach eliminates the need for condensation dehumidification, reduces compressor workload, and eliminates the use of harmful refrigerants. This study marks a pioneering effort in experimentally assessing and analyzing the performance of an integrated SDHED and DPEC system. Parametric studies have been carried out under various ambient and application conditions, yielding impressive experimental results. The DPEC achieves a dew-point effectiveness of 0.9, a DPEC COP of 15.9, and an electric COP of the integrated system reaching an impressive 6.43. The dynamic characteristics of the integrated system have been scrutinized, unveiling the underlying mechanisms of its operation. Additionally, this study outlines development methodologies for the integrated green air conditioning system, encompassing material selection and prototype testing. The findings underscore the potential of the integrated SDHED and DPEC system to enhance indoor comfort and reduce energy consumption concurrently, making it a compelling choice for future environmentally responsible building designs.

Research on Output Characteristics of a Non-Contact Piezoelectric Actuator’s Micro-Displacement Amplifying Mechanism

A non-contact piezoelectric actuator is proposed. The non-contact power transfer between stator and rotor is realized by pneumatic transmission, characterized by fast response, long life, compact structure, and easy miniaturization and control. The structure of the non-contact piezoelectric actuator is designed and its working principle is elucidated. The equation of the relationship between the output displacements of the non-contact piezoelectric actuator’s micro-displacement amplifying mechanism and the input displacements of piezoelectric stack is deduced, and the simulation analysis method of output displacement of the micro-displacement amplifying mechanism is established. Using the equation and the simulation analysis, the output characteristics of micro-displacement amplifying mechanism for the non-contact piezoelectric actuator and their changes along with the system parameters are investigated. The detailed process of optimal design of the micro-displacement amplifying mechanism is given by means of mathematical statistics. The prototype is made and the performance test is carried out. The correctness of the theoretical calculation and simulation analysis is verified by comparing the experimental values with the theoretical and simulated values of the output displacement of the micro-displacement amplifying mechanism. The results show that the initial angle of bridge structure I has an obvious effect on the output characteristics of the micro-displacement amplifying mechanism in the range of 5°–15°. When the lever’s rod length is 13 mm–15 mm, the bridge structure II’s rod length is 6 mm–7 mm, and the power arm length of bridge structure I’s driving lever is 5 mm–7 mm, the bridge structure II’s rod horizontal projection length is 5 mm–6 mm and the output displacement of the micro-displacement amplifying mechanism is larger. Through the optimal design, it is obtained that the bridge structure I’s initial angle is 8°, the lever’s rod length is 15 mm, the bridge structure II’s rod length is 7 mm, and the power arm length of bridge structure I driving lever is 5 mm, the bridge structure II’s rod horizontal projection length is 6 mm, and the simulated output displacement of the micro-displacement amplifying mechanism is 0.1415 mm. The prototype test reveals that as the input excitation displacement decreases, the error increases, while as the input excitation displacement increases, the error decreases. Specifically, when the input excitation displacement is 0.005 mm, the measured output displacement of the micro-displacement amplifying mechanism is 0.1239 mm, resulting in a 19.8% deviation from the theoretical value and a 12.44% deviation from the simulated value. The research work in this paper enriches the research achievements of non-contact piezoelectric actuators, and also provides a reference for designing small structure and large travel micro-displacement amplifying mechanisms of this type of actuator.

Rompi Pintar Pengendara Menggunakan Sensor Kemiringan Untuk Kebutuhan Keselamatan Berbasis IOT

Traffic accidents often occur in everyday life. Many factors cause traffic accidents to occur. Contributors to the high number of traffic accidents are two-wheeled drivers. So an air vest is needed that can reduce the effects of impact if an accident occurs. In this research, an air vest for two-wheeled riders will be designed. Equipped with an IoT-based tilt sensor. This research designs an IoT-based air vest for two-wheeled riders to reduce the impact effects during an accident. This vest is equipped with a tilt sensor which is similar to the function of airbags in four-wheeled vehicles. The way the vest works is that when the sensor detects a certain tilt programmed into the Arduino, the vest will inflate. The main components of this vest are the Arduino Uno ATMega 328 and the MPU-6050 gyroscope sensor. Prototype testing showed a 60% success rate with a development time of 7-10 seconds. However, hands-on testing provided satisfactory results with a 100% success rate and consistent development time of 7-10 seconds. This vest is expected to improve the safety of everyday two-wheeled riders.

Electrolyte Gradients and Capacity Drop in Large Flow Battery Tanks: From Experiments to Fluid-Dynamic Investigations

A study of the effects of electrolyte flow inside the tanks on electrical performance of an industrial-size Vanadium Redox Flow Battery (VRFB) is presented. The concentration of electrolytes feeding the stacks of VRFBs is crucial in determining the device voltage and overall power performance. Usually, the assumption of perfect mixing in the tanks is assumed, but the hydraulic behavior of large VRFB can deviate significantly from this assumption depending on the electrolyte flow rate, stochiometric factor and geometry of the tanks. In this study, the State of Charge (SoC) measurements have been analyzed, starting from the signal produced by an Open Circuit Voltage (OCV) cell. An experimental campaign has been conducted during charge/discharge roundtrip cycles at different current levels and constant stoichiometric factor. Building on the delay in the voltage response of the battery, a fluid-dynamic model was developed to study how the hydraulic behavior of electrolytes inside tanks influences the electrolyte concentration and, consequently, the SoC of the electrolyte that feeds the stack and the electrical time response of the battery. The model indicated that a stratification of charged electrolyte is responsible for this delay resulting in an initial voltage plateau. A different hydraulic behavior was found in each tank and in each charge/discharge phase. These results highlight the tank role in the industrial-scale VRFB performance. References Sanchez-Diez, E. Ventosa, M. Guarnieri, A. Trovò, C. Flox, R. Marcilla, F. Soavi, P. Mazur, E. Aranzabe, R. Ferret, “Redox flow batteries: status and perspective towards sustainable stationary energy storage”, J. Power Sources, 481, (2021) 228804.Kurilovich, A. Trovò, M. Pugach, K. J. Stevenson, M. Guarnieri. Prospect of Modeling Industrial Scale Flow Batteries – from Experimental Data to Accurate Overpotential Identification, Renew. Sust. Energ. Rev. 167, (2022) 112559.Trovò, V. Di Noto, J. E. Mengou, C. Gambaro, M. Guarnieri. Fast Response of kW-Class Vanadium Redox Flow Batteries, IEEE Trans. Sustain. Energy 12, (2021) 2413–2422.Trovò, M. Rugna, N. Poli, M. Guarnieri. Prospects for industrial vanadium flow batteries, Ceram. Int., 49 (14), (2023) 24487-24498.Maggiolo, A. Trovò, M. Guarnieri, “Reactant Flow in Flow Batteries”, in L. Cabeza (ed.), Encyclopedia of Energy Storage, vol. 4, pp. 231-242. Oxford: Elsevier. March 2022.A. Prieto-Díaz, S. E. Ibáñez, M. Vera. Fluid dynamics of mixing in the tanks of small vanadium redox flow batteries: Insights from order-of-magnitude estimates and transient two-dimensional simulations, Int. J. Heat Mass Transf. 216, (2023) 124567.Trovò, N. Poli, M. Guarnieri. New strategies for the evaluation of Vanadium Flow Batteries: testing prototypes, Cur. Opin. Chem. Eng. 37, (2022) 100853. Figure 1

A Flow Battery Path to Long Duration Energy Storage

Solar and wind sources are expected to replace fossil fuels in powering grids, but they are intermittent and non-dispatchable, thus requiring electric energy storage to provide reliable power delivery according to load profile. A dramatic growth in storage capacity is forecasted in to face these issues, up to 1.25 TW and 5 TWh by 2050. Pumped hydro is today the largest-capacity form of grid energy storage worldwide, but it is not expected to grow much, due to geographical and environmental issues. Batteries are often indicated as the solution of choice, notably the dominating Li-ion batteries (LIBs), which are expected to continue to expand. However, their use is limited by economically convenient discharge durations, which do not exceed 4 hours, and raw material costs dynamics. Like other batteries, they present issues e.g. life duration, safety and self-discharge. On the other hand, several studies indicate that to achieve full decarbonization Long Duration Energy Storage (LDES) will be essential, i.e. systems with discharge times above eight hours. Flow Batteries (FBs) have the potentials to provide this performance. In this framework, flow batteries (FBs) are emerging as a competitive option for LDES and several other services. They provide independent sizing of energy and power, thus allowing for long discharge times at full power. Their most developed version, the vanadium FB, exhibits very long life, virtually no self-discharge, operation at room temperature and pressure and absence of fires and explosion hazards. The presentation will discuss their potential and challenges and the undergoing research to improve their performance and competitiveness. References S. Department of Energy. Long Duration Storage Shot. https://www.energy.gov/eere/long-duration-storage-shot, 2021.Long Duration Energy Storage Council. Net-zero power: Long duration energy storage for a renewable grid, technical report, 2021.Jeremy Twitchell, Kyle DeSomber, and Dhruv Bhatnagar. Defining long duration energy storage. Journal of Energy Storage, 60 (2023):105787.Sanchez-Diez, E. Ventosa, M. Guarnieri, A. Trovò, C. Flox, R. Marcilla, F. Soavi, P. Mazur, E. Aranzabe, R. Ferret, “Redox flow batteries: status and perspective towards sustainable stationary energy storage”, J. Power Sources, 481, (2021) 228804.Trovò, M. Rugna, N. Poli, M. Guarnieri. Prospects for industrial vanadium flow batteries, Ceram. Int., 49 (14), (2023) 24487-24498.Trovò, V. Di Noto, J. E. Mengou, C. Gambaro, M. Guarnieri. Fast Response of kW-Class Vanadium Redox Flow Batteries, IEEE Trans. Sustain. Energy 12, (2021) 2413–2422.Trovò, N. Poli, M. Guarnieri. New strategies for the evaluation of Vanadium Flow Batteries: testing prototypes, Cur. Opin. Chem. Eng. 37, (2022) 100853.

Diagnostic Performances of an in-House Immunochromatography Test Based on the Monoclonal Antibody 18B7 to Glucuronoxylomannan for Clinical Suspected Cryptococcosis: a Large-Scale Prototype Evaluation in Northern Thailand.

Cryptococcosis predominantly presents as a meningoencephalitis in Thailand. Early and expeditious diagnosis is essential for reducing both mortality and morbidity associated with cryptococcal meningitis. We aim to define and establish the diagnostic performances between the benchmark commercially available diagnostic kit (CrAg® LFA) and the large-scale prototype of an inexpensive in-house immunochromatographic test (ICT) based on monoclonal antibody (MAb) 18B7. We have developed the large-scale prototype for the rapid detection of cryptococcal polysaccharide antigens by utilizing a single antibody sandwich ICT format employing MAb 18B7, which is highly specific to Cryptococcus neoformans glucuronoxylomannan (GXM) antigens. An in-house MAb18B7 ICT was manufactured in accordance with industry standards under the control of the International Organization for Standardization (ISO) 13485. The diagnostic sensitivity, specificity, and accuracy for the in-house MAb 18B7 ICT were 99.10%, 97.61%, and 97.83%, respectively. The agreement kappa (κ) coefficient was 0.968 based on the retrospective evaluation of 580 specimens from patients living in northern Thailand with clinically suspected cryptococcosis. The data suggest that this in-house MAb 18B7 ICT will be highly beneficial for addressing the issue of cryptococcal infection in Thailand. Moreover, it is anticipated that this inexpensive ICT can play a pivotal role in various global strategies aimed at eradicating cryptococcal meningitis among individuals living with HIV by 2030.

Optimization Design of Automatic Tea Ceremony Teacup Equipment Based on TRIZ Principle

With the development of science and technology and the accelerated pace of society, people are increasingly pursuing a convenient way of life. The art of making tea in traditional Chinese tea culture, although rich in deep cultural heritage, is difficult to adapt its cumbersome steps to the modern fast-paced life. In order to solve this contradiction, this paper applies TRIZ theory to optimize the design of fully automatic tea cup equipment, aiming to realize the automation of the tea brewing process, while retaining the cultural essence of traditional tea art. Through the automation design of the steps of blancher, tea brewing and aroma shaking, combined with modern mechanical design and intelligent control technology, this study proposes an innovative fully automatic tea ceremony teacup equipment program. The solution not only improves the efficiency of tea brewing, but also ensures the quality of tea soup and the experience of traditional tea ceremony through careful design. Ultimately, the feasibility and effectiveness of the proposed scheme are verified through kinematic analysis, prototype testing and user experience evaluation. This study is of great practical significance for the modernization and transformation of the traditional tea ceremony, and also provides a reference for the automation of other traditional processes.

Automatic Tea Ceremony Teapot Robotic Arm Design Based on TRIZ Principle

With the accelerated pace of modern society, there is a contradiction between the tedious steps of traditional tea ceremony and the convenient lifestyle. In order to solve this problem, this study applies the TRIZ theory to optimize the design of the fully automatic tea ceremony teapot robot arm. Through the "nine-screen method", the traditional tea-making process was comprehensively analyzed, the key steps were identified, and the cultural significance and technical requirements of each step were discussed in depth. Using the "technical contradiction matrix" and "physical contradiction" analysis, the potential contradictions in the tea-making process were revealed, and the "physical field model" was applied to construct the problem model and explore the possible solutions. The problem model was constructed by applying the "Physical Field Model", and possible solutions were explored. The study proposes a fully automated tea art teapot robotic arm design program that integrates several key technology modules such as heating and temperature control, plane movement, lid operation, and pouring and dispensing of tea. The program ensures the quality of tea soup and the experience of traditional tea ceremonies through the well-designed robotic arm structure and improves the efficiency of tea brewing at the same time. The structural safety of the design scheme is verified by stress analysis of the connecting plate of the robotic arm and the connecting plate of the teapot base. Finally, the feasibility and effectiveness of the proposed scheme are verified through kinematic analysis, prototype testing, and user experience evaluation. This study is of great practical significance for the modernization and transformation of the traditional tea ceremony and also provides a reference for the automation of other traditional crafts. With the continuous progress of technology, we expect more innovative products combining traditional culture and modern technology to appear in the future so that traditional art can be revitalized in modern society.

Validation of the Protection Scheme for the HL-LHC MBRD Magnet by Simulations and Prototype Tests

Validation of the Protection Scheme for the HL-LHC MBRD Magnet by Simulations and Prototype Tests

Effect of induced electric field parameters on physiochemical characteristics and microorganism of orange juice

AbstractThe induced electric field (IEF) was produced via an oscillating magnetic field, for direct heating of orange juice within a winding coil. During the process, the applied magnetic field was at the range from 0.07 to 1.43 T with 50 kHz. Then, the numerical relationships between excitation voltage, magnetic field, IEF, induced current density, magnetomotive force and energy efficiency were investigated. Since a rectangular wave of excitation voltage was applied, the sawtooth waveform of induced voltage or IEF loaded on the juice was observed. As the magnetic field increased, outlet temperature and induced current density in the juice was improved, the maximum values were 99.5°C and 0.50 A/cm2, respectively, at a conductivity 4.53 mS/cm for the residence time of 4.5 min. However, the efficiency of the process exhibited a negative correlation with the escalation of excitation voltage. At initial colony count about 4.50 log colony‐forming units/mL, the IEF pasteurization reduced all the aerobic microorganisms, molds, and yeasts in the juice, which were evaluated at detectable limits below 1 log colony‐forming units/mL. Moreover, all treatments had no significant effects on pH, total soluble solids and titratable acidity of the juice (p > 0.05). In particular, there was also no significant change in color parameters after IEF pasteurization (p > 0.05). It indicated a significant decrease in vitamin C and total phenolic content of the control groups (p > 0.05), but no significant change in carotenoid content was observed in all treated juice (p > 0.05). heating technology using IEF has the potential to the pasteurization of fruit juice.Practical applicationsInduction electric field technology has progressed rapidly in the past 2 years, it can use oscillating alternating magnetic field to realize the direct heating of liquid food. The process has thermal and non‐thermal effects, at 65–70°C, within 15–30 s to achieve the commercial asepsis of acidic liquid food. After the pasteurization, it can better maintain the color and flavor of the juice. We have assembled a laboratory prototype for testing in the early stage, the processing capacity is at the range of 0–10 L/h. Currently, the system has been able to reach the pilot production scale with the processing capacity of 100–500 L/h. Through the use of highly permeable magnetic materials, the energy consumption per ton of juice processing is controlled at 120 k·Wh level for the pasteurization and is expected to achieve a larger processing capacity in the future.

ITER Magnets Superconducting Joints Prototype Tests in the CEA SELFIE Facility for Operators Qualification

ITER Magnets Superconducting Joints Prototype Tests in the CEA SELFIE Facility for Operators Qualification

Numerical Simulation of the Behavior of Caisson Based on Physical Modeling

Stiffened caissons are a new kind of offshore platform foundation which has been widely used in recent years. Stiffeners are employed to avoid buckling during the installation process. However, they also create a significant challenge in terms of understating the soil-flow patterns and corresponding installation resistance prediction. Although centrifuge and in situ tests can simulate the caisson installation process very well, their high costs prevent their widespread application. Model tests have been widely used in research on caisson behavior during installation, as they are convenient and cost less compared to centrifuge and prototype tests. However, the quantitative conclusions of the resulting predictions of installation resistance have some uncertainties because it is quite hard to strictly follow the similarity principle in 1 g model tests. Therefore, it is important to establish a method to calibrate the data from model tests, providing better estimates of caisson behavior in field tests. In our research, large deformation finite element (LDFE) analyses were conducted to provide insights into differences in the outcomes of caisson installation approaches between prototype tests and 1 g model tests. Prior to carrying out parametric studies, validations were conducted with good results. The results show that normalized soil strength significantly influences the behavior of caissons of various dimensions in 1 g model tests. In uniform clay, caissons exhibit consistent installation behavior; otherwise, they show significant differences. Based on systematic research, this paper reveals the mechanisms of the difference between model tests and prototype tests with different sizes of caissons and identifies the factors influencing these differences.

Development of a Project Module for Strengthening Pancasila Student Profiles Containing Local Wisdom at SDN 6 Pempatan

This study aims to determine the needs of educators and students in implementing the Pancasila Student Profile Strengthening Project activities, as well as the prototype and results of the validity test of the Pancasila Student Profile Strengthening Project module containing Local Wisdom. This study uses quantitative descriptive methods and descriptive statistics with a development research design to the product revision stage. There are 5 stages in this research design, starting from the potential and problem stages, data collection, product preparation, product validation, product revision from the validation results. The subjects of this study were educators and students of grade IV at SD N 6 Pempatan with the object of development in the form of the Pancasila Student Profile Strengthening Project Module containing Local Wisdom. The validation carried out by experts came from ITP Markandeya Bali Lecturers and Grade IV Homeroom Teachers at SD N 6 Pempatan, the validation of the Module was analyzed with descriptive statistics using a Likert scale. The module design was approved with several revisions, including adjusting the cover color, font type on the cover, adding a cover to the student worksheet (LKPD) that needed to be revised. The results obtained in the development research of the Pancasila Student Profile Strengthening Project Module Containing Local Wisdom are categorized as very valid from the results of the expert validation test with an average score of 131 from the interval scale that has been set. The difference between this development research and previous development research can be seen from the contents of the developed module, resulting in a difference in the module validation score. This is influenced by the module validation standards that are adjusted to the curriculum used.

Structural Design and Analysis of Portable Intelligent Wheelchair for Knee Rehabilitation

In order to address the issues of inconvenience, high medical costs, and lack of universality associated with traditional knee rehabilitation equipment, a portable intelligent wheelchair for knee rehabilitation was designed in this study. Based on the analysis of the knee joint's structure and rehabilitation mechanisms, an electric pushrod-driven rehabilitation institution was developed. A multi-functional module was designed with a modular approach, and the control of the wheelchair body and each functional module was implemented using an STM32 single-chip microcomputer. A three-dimensional model was established using SolidWorks software. In conjunction with Adams and Ansys simulation software, kinematic and static analyses were conducted on the knee joint rehabilitation institution and its core components. A prototype was constructed to verify the equipment's actual performance. According to the prototype testing, the actual range of motion for the knee joint swing rod is 15.1°~88.9°, the angular speed of the swing rod ranges from -7.9 to 8.1°/s, the angular acceleration of the swing rod varies from -4.2 to 1.6°/s², the thrust range of the electric pushrod is -82.6 to 153.1 N, and the maximum displacement of the load pedal is approximately 1.7 mm, with the leg support exhibiting a maximum deformation of about 1.5 mm. The intelligent knee joint rehabilitation wheelchair meets the designed functions and its actual performance aligns with the design criteria, thus validating the rationality and feasibility of the structural design.

Piezoelectric Linear Motors with Alternating Action for Motion Servo System of Probe Station

The development of a piezoelectric linear motor is presented in this paper, based on the principle of alternating motion, to meet the acting stroke and accuracy requirements for the probe station’s motion servo system. By partitioning the stator into tangential and normal components, two tangential actuators are affixed to the base, while two normal actuators are fixed on the preloading mechanism, thereby proposing a novel approach for connecting the stator and base. First, the construction and the working principle of the motor were introduced. Subsequently, the motor’s major components were designed through finite element simulation, followed by modeling the motor dynamics and deriving its displacement transfer function. Finally, an experimental prototype was fabricated, and a prototype test system was constructed. The driving method can realize a large stroke operation at a low frequency. The minimum operating frequency of the motor is 1 Hz, the minimum step is 12.55 μm, and the stroke is 105 mm. The study results will promote the development of high-performance probe systems.