General Design Criteria Research Articles

Design Guidelines for Building and Infrastructure Integrated Photovoltaic Modules

The demand for renewable energy is increasing as efforts to decarbonize energy sources continue. Photovoltaic (PV) generation systems are the main contributor to the growth of renewable energy, but limited land availability in countries such as Belgium and Netherlands poses a challenge to their deployment. Integrated PV (IPV) can be a promising solution, but requires special consideration regarding electrical and fire safety, efficiency, durability, cost, and environmental impact in the design process. This study seeks to assist designers of IPV products by guiding the selection of materials, technologies, mechanical designs, and production methods for PV semifabricates (SF). It provides a comprehensive list of general design criteria, each offering various options in terms of bill of materials and production technologies. These options come with their own set of advantages and disadvantages, which are enumerated and quantified wherever feasible. The general design guidelines are validated based on the building‐integrated PV and infrastructure‐integrated PV demonstrators (in this case a noise barrier) being developed in the Solar Energy Made Regional (SolarEMR) project.

Development of a Novel Retinal Surgery Robot Based on Spatial Variable Remote Center-of-Motion Mechanism

Abstract This article reports the design, modeling, and experiments of a novel retinal surgery robot based on spatial variable remote center-of-motion (RCM) mechanism. The general design criteria for parallel mechanisms are proposed, and the planar five-bar mechanisms are evaluated and selected. The planar-spatial evolution process, including the parallel connection of the planar mechanism and the equivalent substitution of joints, is adopted to develop a spatial variable RCM mechanism and then the robot. The mobility and singularity of the robot are analyzed, and the forward/inverse kinematics and workspace are modeled. Dimension optimization is conducted based on a comprehensive performance indicator that characterizes the motion range of linear actuators and the global dexterity performance index of robot. The prototyped robot is fabricated and assembled, and the kinematic calibration is performed. The position error of end-effector is within 34 μm, and both the position error and deviation of the RCM point are within 23 μm. The robot is demonstrated to reach the desired position and execute the RCM motion with high precision simultaneously.

End-rotation-driven kinetic elastica structures: Concept and morphology design

Euler’s elastica, a family of planar curves describing the equilibrium shapes of a thin elastic beam subjected to end forces and moments, demonstrates both geometric versatility and mechanical functionality, leading to its diverse applications across multiple disciplines. Despite its roots in ancient structural engineering practices, the kinetic potential of Euler’s elastica remains largely unexplored in this domain. To address this gap, this paper proposes the concept of end-rotation-driven kinetic elastica (ERKE) structures. This novel kinetic form consists of a sequence of discrete elastica arches transformed from initially straight members by elastic bending. The kinetic behavior arises from manipulating the end rotations of each elastica arch, prompting a continuous flow of motions resulting from adaptations in the arch shape. This adaptive quality opens up limitless possibilities for creating visually captivating dynamic patterns in the overall structure by coordinating the motions of individual arches. As the inaugural exploration of ERKE structures, this paper centers around their conceptualization, with an emphasis on morphology design, which refers to the creation of desirable dynamic patterns. To this end, the paper provides an exposition of the general design procedure and criteria, along with demonstrative examples. The paper also envisions potential application scenarios and identifies research needs, paving the way for future investigations.

A novel rotary ultrasonic motor based on multiple Langevin transducers: design, simulation, and experimental investigation

Traveling wave rotary ultrasonic motors (TRUSMs) have been applied in optical systems, robotics, biomedical and other fields. However, the disadvantages such as short working life, driving performance degradation, and low energy utilization significantly limit the long-term and stable operation of TRUSMs in advanced fields like aerospace mechanisms. To address the above issues, a novel rotary ultrasonic motor based on multiple Langevin transducers is proposed in this paper. First, the structural design, driving principle and general design criteria are described in detail. Then, the structural parameters are optimized by finite element simulation analysis. Second, a prototype is assembled controllably. Subsequently, the impedance test and vibration measurement are carried out. The results show that the traveling wave is successfully generated on the tooth-ring, and all the Langevin transducers are excited to the first-order longitudinal vibration modes, which strongly verify the correctness of design principle. Finally, the driving performance experiment is carried out. The experimental results show that the no-load speed is 62 r min−1 under the pre-pressure of 10 N. The stalling torque is 0.94 N m at the driving voltage of 500 Vp-p. The response characteristics show that the start/stop time are 4.6/5.5 ms, and the angular displacement resolution of clockwise/counterclockwise driving are 6.7/10.2 μrad. The motor proposed in this paper not only exhibits relatively high output performance with excellent vibration characteristics, but also maintains compactness of the structure. The sandwiched structure design effectively avoids the problem that the bonded-type piezoceramic rings in conventional TRUSMs are prone to damage or fall-off when vibrating for a long time. Furthermore, the general design criteria provide a new approach to develop high performance rotary ultrasonic motors. The proposed novel ultrasonic motor is expected to meet the demand for long-term and stable operation in aerospace mechanisms.

Geometric overlapping coefficients for calculating the required emitters per plant in drip irrigation

The designer of irrigation systems must consider a complex combination of emitter type, emitter uniformity, hydraulics, topography, desired water distribution, crop salt tolerance, water requirements, water quality, fertilizer injection, soil salinity, cultural practices, and other site-specific conditions. In contrast to the approaches applied for the hydraulic design of irrigation installations, there is not a clear, general and consolidated design criterion for calculating the number required emitters per plant. In most cases, given the wide spectrum of possible scenarios, only guideline recommendations can be found, and the final decision is often based on the subjective experience of the designer or grower. This paper aims at revising, clarifying and refining the existing published guidelines and methodologies for estimating the required emitters per plant in drip irrigation, focussing on the Montalvo approach. The agronomic design should satisfy, among others, two specific conditions: (i) the emitters should wet at least a minimum threshold of the soil area (or volume) corresponding to the plant for ensuring a proper development of the roots; (ii) overlapping between emitter bulbs is required for merging wetted volumes and avoiding salt concentration near the root zone. Relying on this basis, a thorough theoretical geometric analysis of the overlapping between wet bulbs of contiguous emitters is carried out. As a result, Montalvo's overlapping coefficients are deduced here. This author assumes an identical net wetted area for all emitters in the laterals, but it can be stated that the overlapping areas between emitters differ in extreme emitters and interior emitters, as well as in configurations with one lateral per plant row and two laterals per plant row. Therefore, this study proposes new formulations for the computation of the overlapping coefficient, which need to incorporate the number of emitters as an additional variable, as well as to distinguish between the presence of one or two laterals per plant row, and between grouped and non-grouped emitters. In one lateral per plant row, the original overlapping coefficient underestimates the net wetted area by one emitter and thus overestimates the theoretical number of required emitters. In the case of two laterals per plant row, the original overlapping coefficient overestimates the net wetted area in the interior emitters, and thus underestimates the theoretical number of required emitters per plant. The presented formulations are applied in different practical examples covering a wide range of scenarios. The results allow a general overview of the influence of the soil type, the emitter flow rate, and the selected overlapping ratio in the number of required emitters per plant. The revision of guidelines and methods presented here, complemented with other experimental results and models of soil water dynamics under drip irrigation, might contribute to a better decision making of designers and field engineers.

Energy Efficient Transshipment of Ammonia: A Numerical Study of Various Terminal Concepts

For the global transport and trade of hydrogen, ship transport is of central importance. Ammonia is a promising option for this task. In the ammonia molecule, hydrogen is stored through chemical bonding to nitrogen. In comparison to liquid hydrogen, liquid ammonia shows a higher volumetric energy density and shows advantages in terms of handling. To establish ammonia as a global climate‐neutral energy carrier, the production of green ammonia as well as an efficient supply chain plays important factors. Terminals are an essential part of the process chain as they enable the transshipment from ship to land and vice versa. In this study, the efficiency of various ammonia terminal concepts dealing with both pressure‐liquefied and cold‐liquefied green ammonia is targeted. Multiple terminal concepts are analyzed by thermodynamic investigation as well as numerical simulation. The concepts are compared by system behavior as well as electricity and heat demand under typical bunkering scenarios. The analysis of the concepts produces general design criteria for an efficient terminal design. It is shown that an export terminal is most efficient with a multistage expansion. Furthermore, the integration of the pressure tank as a condenser proves to be particularly suitable for an import terminal.

Design of a trigonal halide superionic conductor by regulating cation order-disorder.

Lithium-metal-halides have emerged as a class of solid electrolytes that can deliver superionic conductivity comparable to that of state-of-the-art sulfide electrolytes, as well as electrochemical stability that is suitable for high-voltage (>4 volt) operations. We show that the superionic conduction in a trigonal halide, such as Li3MCl6 [where metal (M) is Y or Er], is governed by the in-plane lithium percolation paths and stacking interlayer distance. These two factors are inversely correlated with each other by the partial occupancy of M, serving as both a diffusion inhibitor and pillar for maintaining interlayer distance. These findings suggest that a critical range or ordering of M exists in trigonal halides, and we showcase the achievement of high ionic conductivity by adjusting the simple M ratio (per Cl or Li). We provide general design criteria for superionic trigonal halide electrolytes.

Optimizing the Design of the Vapor‐Deposited CsPbCl3‐Based Optoelectronic Devices via Simulations and Experiments

AbstractWide‐bandgap CsPbCl3 perovskite has fueled studies on applications in a variety of newly developing optoelectronic devices, including solar cells, lasers, light‐emitting diodes, and photodetectors. Most of them are now focused on film fabrication and device performance optimization, technology transfer of these proof‐of‐concept devices to the market will necessitate optimization of the device structure to minimize the optical loss and fabrication cost. While device model‐based electro‐optics simulations are considered a powerful method to attain the purpose, during which accurate optical constants are preconditions. Herein, for the first time, the optical constants of CsPbCl3 film through Mueller matrix spectroscopic ellipsometry (SE) are reported. Taking optoelectronic devices in vertical structure as a demonstration, simulations on the distributions of 2D electromagnetic field and photo‐generated electron field are arranged, successfully demonstrating the profile of the photons and electrons inside the devices. The evolution trend of device performance in the experiments matched with the simulations, for device performance is closely related to the photons and photo‐generated electrons. Benefitting from the simulations and experiments, general design criteria of the CsPbCl3‐based optoelectronic and photonic devices are posed, inevitably accelerating their development and commercialization.

Effect of adverse slope on performance of USBR II stilling basin

Abstract This article focuses on the United States Bureau of Reclamation (USBR) Type II stilling basin, which has chute blocks, an end dentated sill, and a flat floor. USBR provides general design criteria to contain the hydraulic jump within the stilling basin. The sequent depth ratio, energy dissipation ratio, and stilling basin dimensions of the hydraulic jump are changed when the bed slope of USBR II stilling basins is changed. This study aimed to investigate the effects of adverse slope on the performance of USBR II stilling basin in terms of sequent depth ratio and energy dissipation. Six discharges ranging from 8 to 33 lps were applied to the USBR II stilling basin with bed slopes (S) of −0.085, −0.055, −0.035, and 0. Results demonstrated that for Q = 13 and 8 lps, the basin performs better than other models with S = −0.085, increasing energy dissipation by about 10% compared to a typical basin due to the formation of a free hydraulic jump downstream dentated end sill. On the other hand, the floor downstream of the dentated end sill needs more protection against this free jump, and this case becomes economically expensive. In other cases, the downstream jump was submerged, resulting in a counterintuitive current and reverse roller based on the submerged ratio, reducing the effectiveness of the stilling basin. In addition, the modified design of the stilling basin resulted in a shorter effective length that included the hydraulic jump downstream spillway, thereby reducing internal friction. As a result, the standard USBR II with a flatbed is less expensive and more efficient than the adverse slope basin.

Perhitungan Shutdown Margin Teras NuScale Menggunakan OpenMC

One of the important reactor safety parameters to study is the issue of shutdown margin (SDM). This study aims to obtain an effective safety design of the NuScale reactor in reviewing the SDM value parameter. SDM calculations are performed using OpenMC, which is a programming code based on the Monte Carlo method. OpenMC is an open source calculation code that has the advantage of access to modifications to the reactor core geometry design. The type of reactor used in this simulation is the NuScale Small Modular Reactor (SMR) which is a Pressurized Water Reactor (PWR) type of reactor. The NuScale core simulation was designed in accordance with the General Design Criterion (GDC), which is a core arrangement that has a Control Rod Assemblies (CRA) regulating bank (RB) and CRA shutdown bank (SB) and UO2 fuel with an enrichment of <4.9%. From the calculation results, the SDM value of NuScale is 17743 pcm. This NuScale core SDM value indicates that the NuScale reactor under study complied with the sufficient safety design limits for all power levels and operating modes.

The role of tyrosine in protein-dopamine based bioinspired adhesives: the stoichiometry that maximizes bonding strength

Nature has evolved adhesive materials adaptive for several different environments by using versatile chemistry that largely relies on two simple components: catechols and polypeptides. Herein, using dopamine as a catechol compound and several model proteins, we show how the adhesive properties can be tuned by controlling the ratio between catechol units and the tyrosine amino acid residue in the protein components. We found that the best bonding strength performance is obtained using a dopamine molar excess to tyrosine of 8.6 ± 2.9. Our study points out a general design criterion and process to obtain high-performance adhesives (>2 MPa) starting from cheap, commercially available, and sustainable raw materials.

Degradation behavior, biocompatibility and antibacterial activity of plasma electrolytic oxidation treated zinc substrates

A ZnO/Zn(OH)2 hybrid coating was fabricated in situ via plasma electrolytic oxidation (PEO) in Na2CO3 electrolyte on pure Zn surface for elucidating the influence of PEO treatment on the degradation behavior of Zn and Zn-based materials. Degradation effects, including surface morphology evolution, corrosion product generation and degradation rate, were systematically investigated through simulated body fluid (SBF) immersion and Hank's solution immersion tests. The results confirm that PEO treatment accelerates the degradation of Zn. With the rise in applied voltage, the initial degradation rate decreases from 0.60 to 0.20 mm/year, whereas the long-term degradation rate can reach 0.50–0.70 mm/year. Especially, the degradation rate acquired at 400 V could meet the general design criteria for degradation rate of biodegradable metallic devices. The corrosion products mainly consist of Zn(OH)2, ZnO, Zn3(PO4)2 and CaP matters. They aggregate to form a bi-layer on the as-formed PEO coating surface. Furthermore, the good in vitro biocompatibility and antibacterial properties of the PEO-treated Zn indicate that PEO is a promising method to treat Zn and Zn-based implants for orthopedic application. When the applied voltage is 400 V, the increased hydrophilicity (WCA <25°), good biocompatibility (cell viability >100 %) and the best enhanced antibacterial performance (53.3 % for S. aureus, 88.3 % for E. coli) compared to that of pure Zn are observed.

Prospects of nanoparticle-based radioenhancement for radiotherapy.

Radiotherapy is a key pillar of solid cancer treatment. Despite a high level of conformal dose deposition, radiotherapy is limited due to co-irradiation of organs at risk and subsequent normal tissue toxicities. Nanotechnology offers an attractive opportunity for increasing the efficacy and safety of cancer radiotherapy. Leveraging the freedom of design and the growing synthetic capabilities of the nanomaterial-community, a variety of engineered nanomaterials have been designed and investigated as radiosensitizers or radioenhancers. While research so far has been primarily focused on gold nanoparticles and other high atomic number materials to increase the absorption cross section of tumor tissue, recent studies are challenging the traditional concept of high-Z nanoparticle radioenhancers and highlight the importance of catalytic activity. This review provides a concise overview on the knowledge of nanoparticle radioenhancement mechanisms and their quantification. It critically discusses potential radioenhancer candidate materials and general design criteria for different radiation therapy modalities, and concludes with research priorities in order to advance the development of nanomaterials, to enhance the efficacy of radiotherapy and to increase at the same time the therapeutic window.

Machine learning-assisted design of AlN-based high-performance piezoelectric materials

A ML model capable of rapidly predicting the piezoelectric coefficient of AlN-based materials, guiding the design of promising piezoelectric materials.

Separating the Effects of Nonorthogonal Variables on the Hot-Injection Synthesis of Core/Thick-Shell (“Giant”) CdTe/CdS Quantum Dots

“Giant” core/thick-shell quantum dot (QD) nanostructures are of interest due to their unusual optical properties and importance as components of more advanced heterostructures tailored to achieve increasingly complex optical functions. However, reliable one-step seeded growth of these structures poses a significant challenge: one must balance multiple competing reaction processes to find the growth regime that realizes spherical shells of both the target size and high crystalline quality. Adjusting synthesis conditions in thicker-shelled reactions is further complicated by multiple nonorthogonal variables that impact the reaction mechanism. These variables include the reaction volume, reaction concentration, and oleic acid (ligand) concentration. Here, we investigate the seeded growth of core/thick-shell CdTe/CdS QDs by adapting a “flash” shelling method. We systematically vary three key reaction parameters (particle concentration, oleic acid:Cd ratio, and Cd–S:CdTe core ratio) over 30+ different thick-shelling reactions to elucidate the separate and intersecting impacts of these parameters on shell growth. Our analysis of the resulting particle quality reveals that the particle concentration of the reaction plays a critical role in the shell growth mechanism. We find the impact of oleic acid to be dependent on the particle concentration for a given shell thickness. We also find that the optimal conditions shift when targeting increasingly thick shells. The results demonstrate the importance of testing and controlling for synthesis variables across a multidimensional parameter space. We develop and present general experimental design criteria to help guide efficient development of new seeded growth reactions that enable reliable synthesis of thick-shelled nanostructures.

Investigation and implementation for forming lead screw by through-feed rolling process with active rotation

A through-feed rolling process with active rotation for manufacturing lead screw has been developed, where the speed matching and stable motion between workpiece and the rolling die during the whole rolling process can be ensured. Its process control, die structure and rolling equipment are relatively simple, and the accuracy of pitch for rolled lead screw can be effectively ensured. The motion characteristic during through-feed rolling process was analyzed, and then the general design criteria for the die were set up. The feasibility of the through-feed rolling process with active rotation was verified by experiment and finite element method (FEM). The verified results indicated that the error of lead-screw pitch between experimental value and designed value is about 0.125 %, and the error between the FEM value and the experimental and designed values is less than 1 %. According to the deformation characteristics of lead screw rolling and the distribution of field variables, the workpiece can be divided into non-deformation zone, entry-angle zone (incremental forming zone), correction zone, exit-angle zone, and full-formed zone. The same position of workpiece will undergo those five forming states in turn. The FEM results indicated that the effective stress and effective strain both gradually increase from the entry-angel zone to the correction zone, and the strain in the exit-angle zone and full-deformed zone are almost quite; the effective stress and effective strain in thread root are larger, and both gradually decrease along thread flank to thread crest; the distributions of stress and strain have a certain periodicity along the axial direction. The results in this study provide a basis for high-efficiency and precise rolling forming of threaded parts with large diameter such as the lead screw.

Deciphering the Rules of Ribosome Binding Site Differentiation in Context Dependence.

The ribosome binding site (RBS) is a crucial element regulating translation. However, the activity of RBS is poorly predictable, because it is strongly affected by the local possible secondary structure, that is, context dependence. By the Flowseq technique, over 20 000 RBS variants were sorted and sequenced, and the translation of multiple genes under the same RBS was quantitatively characterized to evaluate the context dependence of each RBS variant in E.coli. Two regions, (-7 to -2) and (-17 to -12), of RBS were predicted with a higher possibility to pair with each other to slow down the translation initiation. Associations between phenotypes and the intrinsic factors suspected to affect translation efficiency and context dependence of the RBS, including nucleotide bias at each position, free energy, and conservation, were disentangled. The results showed that translation efficiency was influenced more significantly by conservation of the SD region (-16 to -8), while an AC-rich spacer region (-7 to -1) was associated with low context dependence. We confirmed these characteristics using a series of synthesized RBSs. The average correlation between multiple reporters was significantly higher for RBSs with an AC-rich spacer (0.714) compared with a GU-rich spacer (0.286). Overall, we proposed general design criteria to improve programmability and minimize context dependence of RBS. The characteristics unraveled here can be adapted to other bacteria for fine-tuning target-gene expression.

Catalytic activity imperative for nanoparticle dose enhancement in photon and proton therapy

Nanoparticle-based radioenhancement is a promising strategy for extending the therapeutic ratio of radiotherapy. While (pre)clinical results are encouraging, sound mechanistic understanding of nanoparticle radioenhancement, especially the effects of nanomaterial selection and irradiation conditions, has yet to be achieved. Here, we investigate the radioenhancement mechanisms of selected metal oxide nanomaterials (including SiO2, TiO2, WO3 and HfO2), TiN and Au nanoparticles for radiotherapy utilizing photons (150 kVp and 6 MV) and 100 MeV protons. While Au nanoparticles show outstanding radioenhancement properties in kV irradiation settings, where the photoelectric effect is dominant, these properties are attenuated to baseline levels for clinically more relevant irradiation with MV photons and protons. In contrast, HfO2 nanoparticles retain some of their radioenhancement properties in MV photon and proton therapies. Interestingly, TiO2 nanoparticles, which have a comparatively low effective atomic number, show significant radioenhancement efficacies in all three irradiation settings, which can be attributed to the strong radiocatalytic activity of TiO2, leading to the formation of hydroxyl radicals, and nuclear interactions with protons. Taken together, our data enable the extraction of general design criteria for nanoparticle radioenhancers for different treatment modalities, paving the way to performance-optimized nanotherapeutics for precision radiotherapy.

Прикладний аспект критеріїв добору ілюстративного дидактичного матеріалу у підручниках української мови та читання

The article considers the issue of textbook development in accordance with the reform the New Ukrainian School. It presents the essence of the concepts “textbook development” and “the didactic material” based on the scientific literature. The authors argue that the main task of a school textbook remains unchanged, though the changes occur due to the new functions of a book in modern society development. They compare general criteria for textbooks design in the works of Jan Amos Komensky and the criteria developed in alignment with The New Ukrainian School reform. The teachers today are given the opportunity to choose the textbook, which will help them to best implement the content of primary education. Thus, each teacher in schools with the instruction in the Ukrainian language has a wide range of the Ukrainian language and reading textbooks to choose from (10 textbooks (2018) recommended by the Ministry of Education and Science of Ukraine). The authors of the article focus on the practical aspects of the primary school teachers’ evaluation of the materials selected in the textbooks. In-depth analysis allowed specifying the criteria that teachers should pay attention to in choosing the Ukrainian language and reading textbook for the 1st grade based on the practical aspect of the selected didactic materials. The results of the primary school teachers’ survey on the issue of the didactic material selection are presented. The survey revealed that there is a need for special events (seminars, workshops, webinars etc.) aimed at the development of teachers’ quality skills to analyze the didactic content of the textbooks for their objective evaluation and selection. Keywords: textbook, textbook design, didactic material, illustrative material, selection criteria.

Apartment Façade Design Characteristics for Middle and Upper Occupants with Ecological Design Approach

Social and economic conditions affect people’s behavior and preference for housing and the selection of housing area and its design. People with higher economic and social conditions will choose a better quality of housing and the environment. This decision also influences housing preference for apartment design. The quality of the apartment is influenced by a healthy environment, the use of energy that is efficient and can be recycled, using the eco-design approach, and basic facilities are provided. This study focuses on design-based research for designing an apartment building that suits the preferences of middle and upper occupants with an ecological approach. In this study, middle and upper occupant preference determines the shape of the facade design in buildings. In order to determine design parameters and criteria, this study uses a literature review, data analysis, and architectural precedent study. The result finds that several aspects are synthesized and selected as general design criteria apartment buildings. The important parameters in the design of the facade of the building are attractive façade design and emphasize the changing color through vegetation design inside and surrounding the building facades at each season. The building is designed minimalist architecture with a neutral color selection that is combined with natural colors such as wood and stone. Parts of apartment facilities can also be accessed by the occupants easily. Placement of vegetation evenly gives the impression of being close to nature and provides relaxation for each occupant of the apartment building.