Traditional Configuration Research Articles

Profit-oriented balancing of two-sided disassembly lines with resource-dependent task times

Purpose As a result of environmentally conscious production requirements in the world, the concept of disassembly has been a focus of interest by researchers and practitioners over the last two decades. Disassembly is an important process in circular economy to recover and reuse of parts and materials. End-of-life and large-sized products such as minibuses and trucks may be disassembled on two-sided lines. The ability of using both right and left sides of two-sided lines may increase line efficiency and reduce space requirements across the line. This paper aims to address a two-sided disassembly line balancing problem (TSDLBP), which deals with assigning disassembly tasks, various equipments and assistants to the workstations to maximize total net recovery profit of the line. Design/methodology/approach A detailed explanation of the TSDLBP is first presented in the paper. A new 0–1 integer linear programming model is then proposed for the TSDLBP, aiming at maximizing total net recovery profit from disassembly of products. A set of test problems is generated, and an experimental analysis is conducted to make a comparison between traditional one-sided disassembly lines (TOSDL) and two-sided disassembly lines by means of performance improvement rate. Findings Optimal results are obtained in 132 (81.48%) out of 162 the TOSDL balancing problems, while 92 (56.79%) out of 162 the TSDLBP using the proposed model. Total net recovery profits are compared on 88 problems for which optimal solutions are obtained in both the TOSDL and the TSDLBP. Results showed that implementing two-sided disassembly lines provides 29.18% increment in total net recovery profit compared to the TOSDL. Furthermore, the effects of different parameter levels on the net recovery profit are analyzed using two-way analysis of variance. According to the results, implementing two-sided disassembly line configuration increases total net recovery profit of the line significantly compared to traditional disassembly line configuration. Originality/value The use of disassembly lines has become essential because of increasing consumption that results in a huge number of end-of-life products in the world. Two-sided disassembly lines may be preferred for dismantling large-sized products due to their high disassembly capacity and fewer space requirements. This paper proposes a new mathematical model for disassembly line balancing problem. The proposed model differs from the existing models by means of efficiently assigning limited disassembly resources as well as assigning disassembly tasks to the workstations to maximize total net recovery profit of the production system. The model allows decision-makers to consider several resource limitations when balancing their disassembly lines. The paper also provides a comprehensive experimental study to compare traditional and two-sided disassembly lines by means of profitability of disassembly processes.

Mass Optimization of a Multilayered Shield for Transportable Microreactors

The ability to easily transport microreactors is a major selling point for deploying microreactors to remote areas. However, this creates a unique shielding challenge, especially when the microreactor is being shipped after irradiation. A traditional reactor configuration utilizes a separate biological shield and pressure vessel to meet radiological shielding and pressure needs. The limited space available for transportable microreactors for both shielding and pressure vessels requires a revised assessment of separating out the biological shield and pressure vessel. To address these concerns, we examine a nuclear-grade sandwich composite (NGSC) that combines the reactor pressure vessel and biological shielding functions into a single component. Through a series of optimization problems for both transportation and operational use cases, the NGSC is able to minimize dose, minimize the vessel cost, and ensure that weight requirements are met for transportation. Initial results show that using a tungsten-tetraboride cermet in the first two layers of a six-layer NGSC provides adequate shielding for both use cases. These results show promise that an NGSC has enough overlap between operational and transportation cases to help reduce the design space for future analysis and assessment.

An Optimization Design of Piezoelectric Hair Sensor for Oscillatory Flow Detection

Abstract Biological hair is widely found in nature, and they are responsible for sensing and responding to environmental stimuli in living organisms. By simulating biological hair characteristics, they develop hair flow sensor to achieve high sensitivity detection of environmental factors such as small motion and fluid flow field. Output signal is the key indicator of hair flow sensor, and the improvement of output signal is important to the design of hair flow sensor. The existing hair flow sensor sensing structure is generally straight hair, and the output signal is limited by the structure, and the response is small. Using the direct piezoelectric fiber as the initial configuration, we form a new piezoelectric curved fiber by modeling the secondary spline curve and control point. We propose an optimization model for piezoelectric functional hair design using axial strain as a target function. At 100Hz and 500Hz, the output voltage of the optimized model is much higher than that of straight, 10 times and 7 times that of straight, respectively; An optimized curved hair configuration is obtained in a specific frequency band from 1 Hz to 500 Hz, whose average voltage magnitude of 3.1×10−3 V is 4 times greater than that of the straight hair of 7.8×10−4 V with the same size. The curved hair flow sensor breaks the output limitation of traditional straight hair configuration.

Between Tradition and Modernity: The Sociospatial Dynamics of Japanese Residential Architecture from Pre-War to Present

This research examines the evolution of Japanese residential architecture throughout the 20th century, focusing on the transformation of house plans in response to changing societal needs. This study specifically examines how traditional spatial configurations adapted to urbanization, modernisation, and shifts in the family structure. By analysing house plans across three distinct periods—the pre-war and post-Kanto earthquake period, the post-war period, and the post-oil shock period to the present—this research illustrates the transition from detached houses to modern collective housing. Utilising a space syntax methodology, this research quantitatively analyses threshold spaces, circulation, and family gathering spaces to understand their social and architectural implications. Historical analyses are paired with a network analysis of selected house plans, highlighting the persistent significance of traditional elements such as the doma (vestibule) and the en-gawa (verandah) in contemporary designs. The findings demonstrate a significant reduction in the size and complexity of living spaces over time, reflecting broader trends towards efficiency and modernisation in public housing. This research contributes to architectural scholarship by providing a detailed account of how Japanese customary spaces have been reconfigured to accommodate evolving lifestyles, offering insights into the balance between tradition and modern living.

ROS Gateway: Enhancing ROS Availability across Multiple Network Environments.

As the adoption of large-scale model-based AI grows, the field of robotics is undergoing significant changes. The emergence of cloud robotics, where advanced tasks are offloaded to fog or cloud servers, is gaining attention. However, the widely used Robot Operating System (ROS) does not support communication between robot software across different networks. This paper introduces ROS Gateway, a middleware designed to improve the usability and extend the communication range of ROS in multi-network environments, which is important for processing sensor data in cloud robotics. We detail its structure, protocols, and algorithms, highlighting improvements over traditional ROS configurations. The ROS Gateway efficiently handles high-volume data from advanced sensors such as depth cameras and LiDAR, ensuring reliable transmission. Based on the rosbridge protocol and implemented in Python 3, ROS Gateway is compatible with rosbridge-based tools and runs on both x86 and ARM-based Linux environments. Our experiments show that the ROS Gateway significantly improves performance metrics such as topic rate and delay compared to standard ROS setups. We also provide predictive formulas for topic receive rates to guide the design and deployment of robotic applications using ROS Gateway, supporting performance estimation and system optimization. These enhancements are essential for developing responsive and intelligent robotic systems in dynamic environments.

PSIX-3 Dental stick extrusion utilizing spray dried plasma

Abstract Dental stick extrusion utilizes various ingredients to form the ideal texture and quality product. Alternative ingredients to enhance or impact texture, palatability and/or plaque removal can be useful to improve dental stick manufacturing. Spray dried plasma (SDP) is a consistent high protein ingredient commonly utilized in pet food for functional texture properties, enhancing palatability, and supporting overall health. Thus, the study objective was to evaluate how SDP inclusion with other ingredients impacts texture of extruded dental formulas. Three formulas were developed utilizing SDP to replace wheat starch (WS) or Arabic gum in the control formula. The formulas were: Control: WS and gum; SDP1: SDP and WS replacing gum; and SDP2: SDP replacing WS and gum. Dental sticks were made at the Extru-Tech technology testing center using a 525 single screw extruder with the product densification unit (PDU) removed and replaced with a mid-barrel valve and 3 cooling heads to cause densification. The sticks were manufactured as solid square sticks. Generally, a single screw with a PDU, or a traditional parallel-shaft twin screw is used to manufacture dental sticks. However, the equipment alterations used worked like a single screw with a PDU; thus, it would be expected that the results would translate to a traditional single screw configuration. Glycerin at 12% (% to dry feed rate) and chicken fat were added to the pre-conditioner at set rates to optimize expansion and product quality. Processing conditions were monitored and adjusted on the various formulations during production to optimize extrusion. Texture was measured on a TA.XT Plus utilizing an adjustable bridge with a rounded-end knife probe for a 3-point bend. Dental sticks of 8 cm in length were placed over the two bridge spans spaced 5 cm apart to measure maximum force (hardness) and work to peak force (work to break) to determine texture parameters. Ten dental sticks per treatment were analyzed. All formulas utilizing SDP were successful in producing dental sticks. No differences (P > 0.05) were noted in force with SDP formulas compared with control. Work to peak was greater (P < 0.05) in SDP formulas compared with control formula. Formulation matrix impacts results. In the current formulas, both Arabic gum and WS were altered in the formulas and depending on amount of SDP used similar texture was noted. In conclusion, SDP can be incorporated into dental stick formulas and utilized as a processing aide. Overall, depending on target hardness and ingredient matrix, SDP can be an alternative to various ingredients to maintain or improve product quality.

Energy, exergy, economic and environmental studies on a nonflammable eco-friendly mixture for efficient heating in cold regions

As a compelling alternative to fossil fuel combustion, air-source heat pumps face challenges in inefficiency, flammability, and pollution when operated at low ambient temperatures. To address the demand for safe, eco-friendly and efficient heating during wintertime, this work is devoted to exploring a novel refrigerant for air-source heat pumps. The zeotropic mixture has the potential to meet all the above demands at appropriate operating parameters, although specific feasible mixtures are still under investigation. In this work, a novel mixture of carbon dioxide and trans-1,1,1,4,4,4-hexafluoro-2-butene is proposed, with the heating performance being parametrically optimized based on a genetic algorithm. Energy analysis indicates a coefficient of performance improvement of up to 15.7 %, and thus an improvement in heating seasonal performance factor of more than 13.5 % for different cities, compared with traditional configurations. Exergy analysis shows that the low irreversibility of throttling is the main contributing factor to the improvement in energy efficiency. Meanwhile, economic and environmental analyses reveal a payback period of less than 7.5 years and an annual cost reduction of up to 14.5 %, as well as a carbon dioxide emission reduction of over 15.7 %. The sensitivity of operating parameters is analyzed, and other advantages of this concept are discussed as well. The results indicate a safe, efficient, environmentally friendly, and cost-effective air-source heat pump. This study contributes to: 1) providing an energy-efficient and environmentally friendly alternative refrigerant for heat pumps; and 2) promoting the sustainable development of low-carbon energy transformation technology.

All-Layer Electrodeposition of a CdTe/Hg0.1Cd0.9Te/CdTe Photodetector for Short- and Mid-Wavelength Infrared Detection

CdS, CdTe, Hg0.1Cd0.9Te, CdTe, and Ag films were progressively electrodeposited on ITO-coated soda–lime glass to manufacture a short- and mid-wavelength infrared photodetector. A distinctive feature of the applied electrodeposition method is the use of a non-aqueous solution containing ethylene glycol (EG) as the electrolyte in a traditional three-electrode configuration for every film deposition. Using EG as a supplementary electrolyte and using the same deposition conditions with a potential below 0.75 V for all film coatings reduces their environmental incompatibility and offers a low-cost and low-energy route for fabricating the reported photodetector. The produced photodetector has a sensitivity of up to ≈957 nm with a detectivity (D*) of 2.86 × 1012 cm Hz1/2 W−1 and a dark current density (Jdark) of 10−6 mA cm−2. Furthermore, the manufactured photodiode exhibits self-powered performance because Voc and Jsc are self-generated, unlike previously reported photodiodes. The presented all-layer electrodeposition assembly approach can easily be adapted to fabricate sensing devices for different applications.

Effects of extension ladder fly configuration on climbing safety

Fall injuries often occur on extension ladders. The extendable fly section of an extension ladder is typically closer to the user than the base section, though this design is minimally justified. This study investigates the effects of reversing the fly on foot placement, frictional requirements, adverse stepping events (repositioning the foot or kicking the rung), and user preferences. Participant foot placement was farther posterior (rung contacted nearer to toes) in the traditional ladder compared to the reversed fly condition during descent, with farther anterior foot placements during ascent. The reversed configuration had similar friction requirements during early/mid stance and significantly lower frictional requirements during late stance. Increased friction requirements during late stance were associated with farther anterior foot placement and further plantar flexed foot orientation. The reversed fly had 5 adverse stepping events versus 22 that occurred in the traditional configuration. Users typically preferred the reversed fly. These results suggest that a reversed extension ladder configuration offers potential benefits in reducing fall-related injuries that should motivate future research and development work.

An X-band coaxial relativistic klystron oscillator with a novel diode structure packaged with permanent magnet

To achieve compactness and miniaturization for high-power microwave devices, this paper proposes an X-band permanent magnet-packaged coaxial relativistic klystron oscillator (RKO) with a novel diode structure featuring a stair-step cathode. First, by adopting a large-radius anode structure, the emission of beam currents from the side of the cathode surface is diminished, thereby reducing the proportion of the backward current in the beam current from 10% to 7%. Second, a stair-step cathode is used to inhibit the return flow of electron beams from striking the anode and generating plasma. Concurrently, a radially non-uniform coaxial resonant cavity structure is employed to enhance the fundamental wave modulation depth of the electron beam and improve the beam–wave interaction's efficiency. The experimental results show that the novel device outputs a microwave with a frequency of 9.46 GHz and a pulse width of 55 ns. It generates a power output of 1.5 GW with an efficiency of approximately 30.5%, in the case in which the diode voltage is 505 kV, the beam current is 9.7 kA, and the guiding magnetic flux density is 0.4 T. This novel structure surpasses traditional diode configurations by enhancing the beam-to-wave conversion efficiency by roughly 10%, thereby offering substantial support for the compactness and miniaturization of RKO.

Study on Shell-Side Heat Transfer Enhancement Using Cinquefoil Orifice Mixed-Flow Baffle

Abstract For traditional heat exchangers, segmental baffles form a “dead zone” on the leeward side of the baffle, reducing heat transfer efficiency and causing significant pressure loss in the shell side. In response to these issues, this paper proposed a new type of baffle—the cinquefoil orifice mixed-flow baffle which introduces cinquefoil orifices on the segmental baffle. This design retains some cross-flow while also inducing longitudinal jet-flow as the fluid passes through the cinquefoil orifice. Numerical results found that the cinquefoil orifice baffle not only reduces the adverse effects of the “dead zone” but also enhances turbulence in the shell-side fluid flow due to the jet-induced entrainment effect, thereby improving heat transfer efficiency. With identical boundary conditions, the cinquefoil orifice mixed-flow baffle heat exchanger demonstrated superior shell-side heat transfer effectiveness compared to the traditional segmental baffle configuration. For the heat exchanger studied here, when the cinquefoil orifice is positioned closer to the baffle cut, the shell-side Nusselt number can increase by up to 18.8%, concurrently leading to a reduction of 4.62% in shell-side pressure drop. But it is also found that with increasing the number of cinquefoil orifices, the shell-side heat transfer efficiency did not increase monotonically, implying that in addition of the locations of the cinquefoil orifices, the proportion of the longitudinal jet-flow to the cross-flow could be optimized to get a best heat transfer efficiency.

Demand response with PCM-based pipe-embedded wall in commercial buildings: Combined passive and active energy storage in envelopes

Demand response (DR) allows Heating Ventilation and Air Conditioning (HVAC) systems to reduce or shift their electricity consumption during peak periods through the global temperature adjustment strategy. Phase change materials (PCM) based walls are the effective energy storage facilities, storing energy in the pre-cooling period and releasing energy during DR event. However, the traditional configuration of PCM-based wall only allows the passive heat transfer between the walls and the indoor air, requiring a long time to complete the phase change process in the pre-cooling period. This paper presents a novel application of PCM-based pipe-embedded wall (PCM-based PE-wall) in building demand response, which combining active and passive heat transfer mechanism to enhance energy storage rates. The effect of PCM-based PE-walls on demand response is evaluated under two different pre-cooling modes: active pre-cooling only (Envelope-2A) and combined passive and active pre-cooling (Envelope-2B). The results show that the implementation of the PCM-based PE-wall can significantly enhance the overall heat transfer rate of the cooling storage in envelopes and thus improving the demand response performance. Compared to traditional PCM walls (Envelope-1), PCM-based PE-walls (Envelope-2B) could cause additional peak demand reductions of 15.78 % and additional energy reductions of 10.18 % during DR events.

UAV Wing leading edge crashworthiness behaviour under bird strike events: The added value of CF/PA additive solutions versus traditional metallic wing structures

In recent years, an increasing interest in innovative solutions design of aircraft structural components has been raised through both research and industrial fields, aimed at optimising weight and enhancing the ability to withstand both static and dynamic loads. This study compares the structural response to a bird strike phenomenon of a vertical tail of a UAV in standard metallic configuration with the one obtained from an innovative solution, equal in volume but with an internally designed architecture for an additive approach and manufactured by employing a carbon fibre reinforced filament engineered for metal replacement applications (carbon fibre, CF/polyamide, PA). The additive solution proposes the use of a 10 % infill and a lattice structure that completely replaces the traditional aircraft structure concept. This approach leads to a significant weight reduction, approximately 45 % compared to the traditional metallic configuration. The investigation was conducted through explicit numerical simulations considering different impact angles. The numerical model of the bird strike has been assessed by numerical-experimental comparison, simulating the impact of a bird with a flat plate. For this study, the Coupled Eulerian-Lagrangian (CEL) approach has been adopted to perform the simulation. The results were compared in terms of stress distribution, failure analysis, displacements, and energy-time and force-time diagrams. The work demonstrated that using innovative manufacturing processes, such as additive manufacturing, can significantly improve the bird strike resistance of aerospace structures. This improvement is achieved though the production of lighter, structurally collaborative geometries, by reducing the load transferred to the rest of the UAV by about 47 % and decreasing the displacement on the impact area by 53 %.

Meniscus Ripstop Stitches: A Useful Technique for Arthroscopic Repair of Challenging Radial Tears of the Meniscus

Radial meniscal tears can be challenging to address and require advanced arthroscopic techniques for satisfactory repair. When radial tears occur in older patients, the surgeon often encounters suboptimal tissue integrity that presents its own challenges. Incorporating ripstop sutures in tie-grip repair constructs for radial tears has been documented in the literature with favorable biomechanical properties. This Technical Note and accompanying video present a reproducible method for incorporating tie-grip and mobile ripstop stitches to fortify traditional meniscal repair configurations for radial tears. This technique augments the biomechanical strength of repair and may prove useful in poor tissue quality and areas of small focal deficiency, especially in scenarios with repairable but degenerative meniscal tissue. This is particularly relevant considering many repairs fail due to pull-through of sutures within the meniscal tissue.

Improved multi-objective differential evolution algorithm and its application in the capacity configuration of urban rail photovoltaic hybrid energy storage systems

With the rapid expansion of urban rail transit, energy demand is continuously increasing. Integrating photovoltaic (PV) systems into hybrid energy storage systems (HESS) to form a rail transit PV hybrid energy storage system (RTPHESS) is an effective energy-saving and emission reduction measure. However, the integration changes the energy composition of the rail power supply system, making traditional HESS capacity configuration schemes inadequate to meet the stability requirement. In light of this, an RTPHESS model was established aiming at suppressing traction network voltage fluctuations and minimizing the total life-cycle cost of HESS. The model introduces traction network voltage fluctuation rate and HESS total life-cycle cost as evaluation objectives. Based on this, an improved multi-objective differential evolution algorithm (IMODE) was proposed to optimize HESS capacity. Optimal point set theory was used for population initialization to enhance the uniformity and diversity of the initial population, thereby improving global optimization capabilities. During the mutation phase, a hybrid Gaussian-Cauchy mutation strategy was introduced to improve both global and local search capabilities. The proposed algorithm's effectiveness was evaluated using IGD, SP, MS, and ER metrics on eight benchmark test functions with different characteristics, and compared with SaMODE_LS, MODE, MOPSO, MOALO, and MOMGA. Finally, IMODE was applied to the capacity configuration of RTPHESS. The results demonstrate that IMODE outperforms traditional algorithms in terms of accuracy and stability, reducing traction network voltage fluctuations by approximately 4.1 % and lowering the total life-cycle cost to 3,201,100 yuan.

Tapered fiber optic sensor for arterial pulse wave monitoring

Arterial pulse wave monitoring has been recognized as an effective medical diagnostic tool for various cardiovascular diseases. To overcome the barriers in traditional, complex, and expensive detection configurations, new electronic and optical sensors have been developed with their unique advantages. Particularly, various configurations of fiber-optic sensors have been proposed. This paper demonstrates the use of a tapered optical fiber structure to create a sensitive sensor that can detect carotid arterial pulse waves on the skin surface. The demonstrated fiber sensor probe utilizes an in-line Mach-Zehnder interferometer configuration and liquid-gold film coating on the sensor tip to enhance its sensitivity and demonstrate its use by encapsulating the sensor with a flexible elastomer material for detecting arterial pulse waves with a simple testing configuration. Considering the simple fabrication and high sensitivity without a complex demodulation scheme, the proposed sensor has broad implementation in biomedical health monitoring systems.

Numerical modeling of the effects of impact conditions, foundation stiffness, and cable pretension on the behavior of high-tension guard cable systems

Cable barriers are one type of road restraint system commonly used on highways across the United States to contain and redirect errant vehicles and to prevent crossover accidents. These systems are typically tested under the provisions from safety manuals considering standard crash conditions (e.g., vehicle speed and impact angle). To understand the performance of cable barriers, it is important to evaluate the effects of non-standard crash and system conditions, including various vehicle speeds, impact angles, foundation material stiffness, and cable pretension loads. For that purpose, we created a set of full-scale finite element models in LS-DYNA to assess the effects of these non-standard conditions on the performance of high-tension cable barrier systems. The results from the models show that soft soils and under-tensioned systems yield higher cable deflections. Moreover, the results indicate that speeding vehicles colliding at non-standard angles increase cable tensions by up to 91% and cable deflections by up to 318%. These findings highlight the importance of evaluating cable barrier performance under more severe scenarios, which could lead to system failure and more severe collision consequences.

Interpenetrated Structures for Enhancing Ion Diffusion Kinetics in Electrochemical Energy Storage Devices

HighlightsA new and compact device configuration was created with two interpenetrated, individually addressable electrodes, allowing precise control over the geometric features and interactions between the electrodes.The interpenetrated electrode design improves ion diffusion kinetics in electrochemical energy storage devices by shortening the ion diffusion length and reducing ion concentration inhomogeneity.The device with interpenetrated electrodes outperformed the traditional separate electrode configuration, enhancing both volumetric energy density and capacity retention rate.

Design methodology of functionally graded cellular materials: Manipulating design parameters of triply periodic minimal surfaces through three-dimensional density distributions

Functionally Graded Cellular Materials (FGCM) with variable volume fractions have demonstrated significant advantages, including weight reduction, improved stiffness, and enhanced load distribution, when compared to uniform density counterparts. Their design is often characterized by the application of a density distribution to locally modify Representative Volume Elements (RVEs). Current studies have explored the application of Triply Periodic Minimal Surfaces (TPMS) topologies, given their capability to create seamless and interconnected structures, thus avoiding stress concentration issues commonly encountered in traditional lattice configurations. Consequently, this paper introduces a design methodology tailored to TPMS-based FGCM allowing for independent or simultaneous adjustments of RVE thickness and size. Models for predicting relative density as a function of the RVE design parameters of Primitive and Gyroid topologies are presented and discussed. These models are employed to adapt the topologies to three-dimensional density distributions. The proposed method is implemented as a set of design tools and is illustrated for the studied TPMS topologies.

A Palladium-Containing Polyoxotungstate with Anisotropic Proton Conductivity.

Here, a case of bilayer heterojunction Pd-containing polyoxotungstate (POW), connecting a Te3Pd3 ring and an Anderson-like TeW6 cluster, has been synthesized. The Anderson-like cluster is the first example in POW. The coordination of Pd in the ring with the S atom on the sulfo group breaks the traditional coordination configuration of Pd and O in polyoxometalates (POMs), enriching the structural types of Pd-containing POMs. In addition, the hybrid bilayer heterojunction structure at the molecular level not only provides high thermal stability but also results in spatial arrangement anisotropy, leading to up to five times the anisotropic proton conductivity.