Detailed Design Research Articles

Stenting with dual-layer CGuard stent in acute sub-occlusive carotid artery stenosis and in tandem occlusions: a monocentric study

PurposeDouble-layer design carotid stents have been cast in a negative light since several investigations reported high rates of in-stent occlusions, at least in the acute setting of tandem occlusions. CGuard is a new generation double-layered stent that was designed to prevent periinterventional embolic events. The aim of this study was to analyze the safety and efficacy of the CGuard in emergent CAS and for the acute treatment of tandem occlusions in comparison with the single-layer Carotid Wallstent (CWS) system.MethodsAll patients who underwent CAS with CGuard or CWS after intracranial mechanical thrombectomy (MT) between 11/2018 and 12/2022 were identified from our local thrombectomy registry. Clinical, interventional and neuroimaging data were analyzed. Patency of the stent was assessed within 72 h. Intracranial hemorrhage and modified Rankin score (mRS) at discharge were the main endpoints.ResultsIn total, 86 stent procedures in 86 patients were included (CWS: 44, CGuard: 42). CGuard had a lower, but not statistically significant rate (p = 0.431) of in-stent occlusions (n = 2, 4.8%) when compared to the CWS (n = 4, 9.1%). Significant in-stent stenosis was found in one case in each group. There was no statistically significant difference in functional outcome at discharge between the two groups with a median mRS for CGuard of 2 (IQR:1–5) vs. CWS 3 (IQR:2–4).ConclusionIn our series, the rate of in-stent occlusions after emergent CAS was lower with the dual-layer CGuard when compared to the monolayer CWS. Further data are needed to evaluate the potential benefit of the design in more detail.

Generation of parallel Bessel beams and cosine Bessel beams based on metasurface

In view of the powerful light field manipulation ability of metasurface and the wide applications of Bessel beams, parallel Bessel beams are generated based on a simple metasurface design. The proposed metasurface consists of cross nanoholes and the orders of the generated parallel Bessel beams can be modulated. Theoretical analysis provides the detailed design principle of metasurface to generate parallel Bessel beams. Parallel Bessel beams and parallel cosine Bessel beams are generated and the simulation and experimental results give the verification. With respect to the single Bessel beam, the generated parallel Bessel beams with controllable orders may bring more conveniences for the applications of Bessel beams. The simple geometry, parallel output and the controllable order will inspire wider applications of Bessel beams.

Development of a muon linac for the J-PARC Muon g − 2/EDM experiment

At Japan Proton Accelerator Research Complex (J-PARC), a muon linac is being developed for future muon g−2/Electric Dipole Moment (EDM) experiments. The muon linac starts with an ultra-slow muon (USM) source that generates muons with an extremely small momentum of 3 keV/c (kinetic energy W=25 meV) by laser ionization of thermal muonium. The generated USMs are accelerated to 5.6 keV by an electrostatic field and injected into a radio frequency quadrupole (RFQ). The injected muons are accelerated to 0.34 MeV by the 324-MHz RFQ. Then, the energy of the muon beam is boosted to 4.5 MeV with a 324-MHz interdigital H-type drift tube linac (IH-DTL). Following the IH-DTL, 1296-MHz disk-and-washer (DAW) structures accelerate the muon up to 40 MeV. Finally, the muons are accelerated from 40 MeV to 212 MeV using a 2592-MHz disk-loaded traveling wave structure (DLS). In this paper, details of the linac design and the recent progress toward the realization of the world's first muon linac will be discussed.

Terahertz dual-band bandpass filter based on spoof surface plasmon polaritons with wide upper stopband suppression.

In this paper, a terahertz (THz) dual-band bandpass filter based on spoof surface plasmon polaritons (SSPPs) with wide upper stopband suppression is proposed. The filter utilizes two types of SSPP unit cells loaded on a double-sided quasi-SSPPs transmission line to achieve dual-band filtering responses and wide upper stopband suppression simultaneously. The performance and bandwidth of the filter's passbands can be adjusted by modifying the SSPP unit cells within the dual-band filtering part. The detailed design method is provided to enhance understanding of the operating principle of the presented filter. The simulation results of the designed THz filter demonstrate its excellent dual-band filtering performance. It features a wide stopband spanning from 0.91 to 1.45 THz with |S21| < -35 dB. To validate the proposed approach, a microwave filter with a similar design is implemented. Finally, the simulated and measured S-parameter responses of the filter are provided for comparison and evaluation.

State Control Design of Ostensible Metzler Linear Systems with Unsigned Input Parameters

This paper deals with the design of a complete state control for input unsigned, rank deficient matrix parameters of a linear system with system dynamics defined by ostensible structures of Metzler matrices. The proposed solution is based on the principle of diagonal stabilization of positive systems and uses a stabilizing additional component over the decomposition of the Metzler matrix in solving the incomplete internal positivity of such linear system structures. The novelty of the proposed approach is the unified representation of the parametric constraints of the Metzler matrix and the structurally constrained system inputs using linear matrix inequalities, which guarantees that the closed-loop system will be asymptotically stable. Despite the complexity of the constraint conditions on this class of linear continuous systems, the design conditions are formulated using sharp linear matrix inequalities only. A detailed design process is presented using a system-linearized mathematical model to verify the superiority and practicality of the proposed method.

Artificial Intelligence (AI) and Knowledge-Based Engineering (KBE) in Ship Design: Bridging Tradition and Technology Through ACQUAINT

_ Despite the limited use of artificial intelligence/knowledge-based engineering (AI/KBE) in industries with small series or one-off designs, our study demonstrates the technical feasibility and potential benefits of implementing AI/KBE in ship design processes. This research presents the development of “ACQUAINT,” uniquely designed to address the complexities inherent in bespoke shipbuilding. Central to this module is a robust AI-driven inference engine, integrated seamlessly with AutoCAD through a Python-based interface, facilitating a novel approach in shipbuilding’s detail and production design phases. The module’s capability to generate optimal designs autonomously—grounded in a deep understanding of design rules, constraints, and requirements—substantially reduces the reliance on human interaction. Our initial proof of concept with “ACQUAINT” showcases measurable advancements in ship design accuracy and efficiency, highlighting AI KBE’s transformative impact in shipbuilding and setting a foundation for future research and practical applications. Keywords ship design; artificial intelligence; knowledge-based engineering; self-learning system; software development; ACQUAINT; CAD/CAM software; computers in construction; computers in design; modernization; ship structure

PENERAPAN METODE ICONIX PROCESS DALAM PENGEMBANGAN SISTEM INFORMASI KEPEGAWAIAN UNIVERSITAS CATUR INSAN CENDEKIA

Accurate and precise information plays a crucial role in producing high-quality Human Resources (HR) or employees at Universitas Catur Insan Cendekia. Higher education institutions have various needs in managing HR data, including personal information, educational history, rank classification, and other important employee details. The Iconix Process methodology is employed in the development of the Human Resource System at Universitas Catur Insan Cendekia, starting with requirements analysis, diagram creation, initial design, detailed design, coding, testing, and implementation. The result is a more structured, easily accessible, and efficient management of HR data through a website. Keywords: Iconix Process, Development, Information Systems, Personnel

Innovative Thinking Approach in Designing Teaching Materials for Ilm Badi Course: A Comprehensive Framework for Enhancing Students' Writing Skills

Students face several challenges in learning Ilm Badi, including difficulty understanding learning objectives, a lack of comprehension regarding the classification in Ilm Badi materials, insufficient visual stimuli in teaching materials, and challenges in generating new sentences. These issues indicate a mismatch between theoretical understanding and practical language skills. Therefore, this study aims to design teaching materials for Ilm Badi with an innovative thinking approach to stimulate students' writing creativity. The research method employed is Research and Development (R&amp;D), integrating the instructional material design procedure by Sa'ud with the ADDIE model. Data were collected through interviews, observations, and questionnaires. The results indicate that the innovative thinking approach is relevant in strengthening creative thinking processes in general and supports the teaching of Ilm Badi with a more progressive and contextual approach. The teaching materials produced through detailed design stages involve composing content in Arabic and Indonesian, utilizing additional visualizations, and designing exercises to encourage students' innovative thinking abilities. The teaching materials design process includes collaboration with relevant experts. It undergoes expert assessments, resulting in teaching materials that meet standards for use in Ilm Badi learning, emphasizing innovative thinking. Further studies are necessary to test the designed teaching materials' effectiveness empirically.

Industrialized Exterior Retrofit Projects: A Review

Abstract The building stock is a large consumer of energy, and measures are being taken to reduce energy use in new construction. However, to reach the world’s net zero goals, significant changes need to be made to existing buildings. There are many different methods that can be used to renovate a building, including partial demolition and rebuilding, interior retrofit, or exterior retrofit. The focus of this review is on prefabricated exterior retrofit projects. The entire process of undergoing industrialized exterior retrofits will be explained, including Initiation and Viability, Building Capture and Imaging, Detailed Design, Manufacturing, Installation, Operation, Maintenance, and Monitoring. Past industrialized retrofit projects will be presented, and their successes and limitations will be discussed. Common issues and barriers to entry/adoption are examined to give an understanding of what is required to make prefabricated industrialized exterior retrofits work in North America.

Dynamic facades for sustainable buildings: A review of classification, applications, prospects and challenges

Dynamic facades (DFs) can potentially transform how we design and experience buildings. Their adaptability to changing environmental conditions can significantly reduce energy consumption and CO2 emissions, while also enhancing the comfort of building occupants. Smart materials and automated systems enable these facades to optimize daylighting, control heat gain, and improve ventilation – resulting in energy savings of up to 50% and CO2 emission reductions of up to 40% compared to traditional static facades. Despite the challenges of high initial costs and maintenance requirements, this study proposes a classification scheme for DFs, providing a systematic approach to understanding their diverse technologies and potential applications. This study aims to fill a gap in the lack of comprehensive information on DF design concepts, configurations, and details. A thorough review of 26 international case studies underscores the real-world energy-saving impacts of DF designs. To fully realize the long-term benefits, this research underscores the crucial need for in-depth techno-economic analysis that considers the life cycle costs (LCC) of DFs. Such analysis will equip stakeholders with the knowledge to make informed decisions that balance economic considerations with the environmental benefits of DFs. Despite the remaining challenges, DFs offer a promising path towards more energy-efficient buildings and healthier and more comfortable indoor environments. The performance gains demonstrated in this study make DFs a compelling solution for shaping the future of sustainable building design. However, continued research focused on DF systems classification, performance analysis, and economic viability will be crucial to making this innovative technology accessible and impactful on a broader scale.

Structural optimization using a genetic algorithm aiming for the minimum mass of vertical axis wind turbines using composite materials

A wind turbine comprises multiple components constructed from diverse materials. This complexity introduces challenges in designing the blade structure. In this study, we developed a structural optimization framework for Vertical Axis Wind Turbines (VAWT). This framework integrates a parametric Finite Element Analysis (FEA) model, which simulates the structure's global behavior, with a Genetic Algorithm (GA) optimization technique that navigates the design domain to identify optimal parameters. The goal is to minimize the mass of VAWT structures while adhering to a suite of complex constraints. This framework quantifies the mass reduction impact attributable to material selection and structural designs. The optimization cases indicate that blades made from Carbon Fiber Reinforced Plastics (CFRP) materials are 47.1 % lighter than those made from Glass Fiber Reinforced Plastics (GFRP), while the structural parts are 44.8 % lighter. This work also provides further recommendations regarding the scale and design of the structures. With the materials and structural design established, future studies can expand to include more load cases and detailed designs of specific components.

Lessons learned from 10 years of wind tunnel tests on small wind turbines designed by students

This article discusses results from an international contest, open for university student teams (bachelor and master), involving the design, construction, and testing of small wind turbines in a large wind tunnel. The wind tunnel has an outlet of 2.85 x 2.85 m allowing a maximum rotor swept area of 2 m2 without significant tunnel effects. Both horizontal and vertical axis wind turbines are part of the competition. The turbines are evaluated by an external jury of industry experts based on criteria such as Annual Energy Production, cut-in wind speed, innovations, design, and sustainability. Although the contest has been initiated in 2013 with an educational focus, it has also evolved into a valuable database for scientific purposes by providing a decade worth of performance measurements for roughly 9-10 various turbine concepts each year. The collected data may serve as a unique validation resource for assessing the accuracy of design codes in modelling diverse turbine concepts thanks to detailed design reports with model descriptions accompanying each turbine (such turbine descriptions are often considered confidential for field measurements). The paper aims to explore the scientific value of this database by comparing calculations with measurements, offering explanations where possible, and reporting intriguing findings on unconventional concepts’ performance. Even though not all observations could be explained fully they provide food for thought. Recommendations are provided for both students to enhance their designs and for contest organizers to elevate the scientific value of the measurements in future contests.

Efficiency and mass optimization for space nuclear power systems with closed Brayton cycle loops

Space nuclear power systems should be strictly limited in mass and size. Lack of detailed designs, mass estimation in the general design phase usually relies on simple and empirical models that leave too much design margin from the limits. Accurate mass estimation of space nuclear power systems is key to minimize the design margin and maximize the system performance in the general design phase. In this paper, new mass estimation models are proposed for the main components of space nuclear power systems, including nuclear reactor, shield, turbine, compressor, heat exchanger, and thermal radiator. The mass estimation models are more accurate by incorporating principles of nuclear physics, thermal hydraulics, and structural mechanics to the component designs. Combined with thermodynamic models and genetic algorithm, the MEGREZ code is developed to optimize the system performance by setting efficiency and mass as dual objectives. The code verification results indicate that the deviations between and the Jupiter Icy Moons Orbiter project parameters and the code calculated values are only 0.4% for system efficiency and 2.1% for system mass. The optimization for the Jupiter Icy Moons Orbiter project shows that the optimal molecular weight of helium-xenon mixture is the minimum value for single-stage turbomachinery limits. Additionally, the impacts of potential technological degradation, such as increased heat exchanger thermal resistances, higher frictional factors, and decreased turbomachinery efficiency, on system performances are discussed. The results show that turbomachinery efficiency presents the strongest influence on the system-specific mass; a 0.04 reduction in the polytropic efficiency of the compressor or turbine results in more than a 10% increase in system-specific mass.

NREL 15-kW: An Advanced Horizontal-Axis Reference Turbine for Distributed Wind

Distributed wind energy can play a significant role in the renewable energy landscape. A recent study conducted by the National Renewable Energy Laboratory (NREL) identified the lack of availability and utilization of reference wind turbine models as a major hindrance in the development of the distributed wind energy technology sector, even though such models are widely used in offshore and land-based wind research. Therefore, NREL is developing three reference wind turbine architectures, also called archetypes, for distributed wind energy applications. This paper describes the detailed design and modeling of the first of the three reference turbine archetypes, called the NREL 15-kW turbine. It is a passive-yaw, upwind turbine with a rated power of 15 kW.

Simulation test of 50 MW grid-connected “Photovoltaic+Energy storage” system based on pvsyst software

With the implementation of the national “double carbon” strategy, the installed capacity of new energy power generation continues to grow, and stable photovoltaic power generation solutions have received increasing attention. The PV + energy storage system with a capacity of 50 MW represents a certain typicality in terms of scale, which is neither too small to show the characteristics of the system nor too large to simulate and manage. This study builds a 50 MW “PV + energy storage” power generation system based on PVsyst software. A detailed design scheme of the system architecture and energy storage capacity is proposed, which is applied to the design and optimization of the electrochemical energy storage system of photovoltaic power station. Based on the results of PVsyst operation simulation test, the operation performance of 50 MW “PV + energy storage” power generation system is explored. The results show that the 50 MW “PV + energy storage” system can achieve 24-h stable operation even when the sunshine changes significantly or the demand peaks, maintain the balance of power supply of the grid, and save a total of 1121310.388 tons of CO2 emissions during the life cycle of the system. The various parts of the system, including the photovoltaic array, the energy storage unit and the grid interface, demonstrated efficient collaborative performance in the simulation environment of PVsyst.The analysis of power generation shows obvious seasonal changes. The unit power generation is higher from March to September, and the more the power generation is the overall annual power generation shows good consistency and predictability under the regulation of the energy storage system. Through the analysis of different operating scenarios, the key parameters that affect the system performance are further determined, such as lighting conditions, battery storage capacity, power consumption device efficiency. For lighting conditions, the total radiation amount of the incident lighting surface takes the most proportion in the interval of 380–900 W/m2 and 25-60kwh/m2/Bin. The simulation test also reveals the important role of energy storage unit in power grid demand peaking and valley filling, which has an important impact on balancing the instability of photovoltaic power generation and improving the system response ability.

Experimental study on the influence of welding structure details of TC4 titanium alloy under thermo-vibration coupling environment on vibration fatigue life

The widespread application of titanium alloy materials in aerospace structural design makes them susceptible to thermo-vibration coupling fatigue failure in harsh vibration and thermal environments. Vibration fatigue issues significantly affect the safety and operational reliability of aircraft. In order to obtain optimal design details for titanium alloy welding structures under thermo-vibration coupling conditions, experimental specimens with different structural details of TC4 titanium alloy welding structures were designed to simulate actual structural designs. The structural details included skin with U-shaped supports at different angles, skin with L-shaped supports, and skin with T-shaped supports. A thermo-vibration coupling vibration fatigue test system was established, and vibration fatigue tests were conducted at a temperature of 150°C. All structural fatigue crack failures occurred at the welds. The experimental results were statistically analysed, and using the Chauvinet criterion, abnormal data points were removed. The influence of structural details on vibration fatigue life was determined through F-tests. It was found that for the skin with a U-shaped support structure, a support angle of 90° resulted in a longer vibration fatigue life. When comparing skin with T-shaped support and skin with L-shaped support structures, the T-shaped support structure exhibited a longer vibration fatigue life. Among the three structural types, the skin with a T-shaped support structure has the longest vibration fatigue life. These experimental conclusions serve as important references for the design of thin-walled structures in aircraft structural design.

Initial data from a phase 1, first-in-human clinical trial for T-Plex, a multiplexed, enhanced T cell receptor-engineered T cell therapy (TCR-T) for solid tumors.

2542 Background: Solid tumors are notoriously heterogenous with highly variable antigen expression and an immunosuppressive microenvironment. HLA loss of heterozygosity (LOH) has also been identified in up to 40% of solid tumors, allowing tumor cells to evade T cell attack. To overcome these issues and a lack of potent endogenous antitumor T cells in cancer patients, TScan has developed T-Plex, a multiplexed cell therapy comprising two to three different TCR-Ts, chosen from a collection of TCR-Ts called the ImmunoBank. Product and study design details were presented at ASCO 2023 (Abstract #2554). Methods: A screening protocol (NCT05812027) pre-identifies patients with solid tumors any time during clinical care, enabling rapid enrollment into the treatment protocol (NCT05973487) upon disease progression. TCR-Ts currently in the master protocol target PRAME on HLA-A*02:01; HPV16 on HLA-A*02:01; MAGE-A1 on HLA-A*02:01, HLA-A*01:01, or HLA-C*07:02; or MAGE-C2 on HLA-B*07:02. All TCR-Ts in the ImmunoBank and master protocol are first tested as single therapies in dose levels 1 and 2 before becoming available for multiplexing in dose levels 3 and 4. Results: From September 2023 to the time of abstract submission, 140 participants with a variety of solid tumors were enrolled in the screening protocol and are in different stages of screening. To date, 65% have ≥1 HLA match, and 20% and 6% have 2 and 3 HLA matches, respectively, highlighting the advantage of including TCR-Ts targeting multiple different HLA types within the same master protocol. Of those who have completed target screening, 92% express at least one target and 65% qualify for at least one TCR-T. Intratumoral heterogeneity of target expression was observed even with the most prevalently expressed target, PRAME, supporting the rationale for multiplexed TCR-T treatment. Although HLA-LOH affects only half of HLA genes and the remaining intact HLA alleles in tumors can still be recognized by TCR-Ts, about 13% of participants had LOH of the targeted HLA allele, excluding them from TCR-T treatment. Conclusions: Initial data indicate that the combination of HLAs and targets in the ImmunoBank results in ≥1 TCR-T match for the majority of solid tumor patients evaluated to date, and many patients qualify for multiplexed TCR-T treatment. LOH testing can prevent selection and treatment with a TCR-T that would not confer benefit. The proportion of patients eligible for multiplexing is expected to increase as the ImmunoBank grows. Updated data on screened and treated patients will be presented at the meeting. Clinical trial information: NCT05973487 ; NCT05812027 .

Implementing Failure Mode &amp; Effect Analysis(FMEA) on Framework Structure

Abstract: The Failure modes and effects analysis (FMEA) is one of the most practical design tools implemented in the product design to analyze the possible failures and to improve the design. The use of FMEA is diversified, and different approaches are proposed by various organizations and researchers from one application to another. The question is how to use the features of FMEA along with the design process. This research focuses on different types of FMEA in the design process, which is considered as the mapping between customer requirements, design components, and product functions. These three elements of design are the foundation of the integration model proposed in this research. The objective of this research is to understand an integrated approach of FMEA in the design process. Significantly, an integration framework is developed to integrate the design process and FMEA. Then, a step-by-step FMEA-facilitated design process is proposed to apply FMEA along with the design process. The analysis should always be started by someone listing the functions that the design needs to fulfil. Functions are the starting point of a well done FMEA, and using functions as baseline provides the best yield of an FMEA. After all, a design is only one possible solution to perform functions that need to be fulfilled. This way an FMEA can be done on concept designs as well as detail designs, on hardware as well as software, and no matter how complex the design.

Subcontractor Engagement in the Two-Stage Early Contractor Involvement Paradigm for Commercial Construction

Commercial construction projects (CCPs) in New Zealand contribute more to the economy than other project types. However, many face cost and time increases due to inadequate planning. Procurement pathways that involve contractors during design development provide more time to plan, collaboratively. Nevertheless, most projects are procured through traditional tender where contractors are only involved after detailed design. Through two-stage early contractor involvement (2S-ECI), contractors can provide design buildability advice for complex projects, contribute value management, carry out exploratory works, and order materials. The role of subcontractors in 2S-ECI can be significant. Six semi-structured interviews were conducted with clients, consultants, main contractors, and a subcontractor involved in large complex commercial construction projects. The findings build on the emerging body of knowledge about 2S-ECI by providing insight into subcontractor early involvement. Project complexity and market conditions were the main reasons for early subcontractor involvement. Common challenges include a lack of information sharing among the parties, non-competitive selection, and a lack of standard contract documentation. Opportunities for improvement include clarifying client expectations, educating stakeholders, and providing more equitable compensation for pre-construction services. Key drivers for subcontractor involvement include project complexity, market conditions, ordering long-lead-time systems, and performance specifications. Specialist early sub-trades include electrical, mechanical, structural steel, and façades. Subcontractors should typically be engaged as early as possible, often concurrently via main contractors to share performance risk. Pre-construction services provided by subcontractors include planning and sequencing; design buildability analysis; risk mitigation; value management; budget advice; systems procurement; design solutions; and document control systems. Advantages include obtaining specialist project knowledge and improving completion certainty. Producing a pre-construction services agreement (PCSA) for subcontractors may address challenges, as has been carried out for main contractors, but there is still a gap in the contractual framework for 2S-ECI for subcontractors.

Modelling guided energy management system for a hydrogen–fuelled harbour tug

The use of hydrogen as a source of fuel for marine applications is relatively nascent. As the maritime industry pivots to the use of alternate low and zero-emission fuels to adapt to a changing regulatory landscape, hydrogen energy needs to present and substantiate a technical and commercially viable use case to secure its value proposition in the future fuel mix. This paper leverages the technoeconomic and environmental assessment previously performed on HyForce, a hydrogen-fuelled harbour tug which has shown encouraging results for both technical and commercial aspects. This study aims to create a digital twin of HyForce to accurately predict her operability in real-world scenarios. The results from this study identify the strengths and drawbacks of the proposed use case. This is achieved by embedding the detailed design of HyForce in a virtual environment to further evaluate its operational performance through Computational Fluid Dynamics (CFD) simulations of realistic environmental conditions such as wind, wave, sea currents, and friction attributed to the properties of seawater. The results from this study indicate a base case power requirement of 93 kW to 1892 kW to achieve speeds of 5 to 12 knots in the absence of external environmental influences. Consequently, the speed of HyForce has a profound impact on total resistance peaking at 97.3 kN at 12 knots. Seawater properties such as low seawater temperature of 0 °C, and a high salinity of 50 g/kg increased friction. Additionally, wind speeds of 10 m/s acting on HyForce, delivered a resistance of 3 kN. However, these will be well mitigated through the design of the propulsion system which will be able to deliver a thrust power of 1892 kW and with assistance from the energy storage systems produce 2 MW of power to overcome the resistance experienced. The findings presented in this paper can serve as a foundation for constructing a robust model for the development of a predictive controller for future work. This controller has the potential to optimize the configuration of hydrogen and battery energy storage, aligning with desired cost functions.