Short Cycle Time Research Articles

Experimental validation of multi-vial control for primary drying in a pilot-scale unit

Primary drying is the bottleneck of pharmaceutical lyophilization, as it represents the most time and energy-consuming stage and largely determines the quality of the final product. The common practice runs the process under pre-calculated input profiles while considering average drying dynamics for the batch. This results in conservative and underperforming cycles. In this regard, the paper proposes and experimentally validates an in-line control strategy for primary drying. It explicitly accounts for intra-lot drying heterogeneity using three models, each one calibrated for a reference vial position in the chamber. Two separate experiments evaluate the proposed framework: offline and in-line process control. Validation on a pilot-scale unit shows a cycle time reduction of the proposed approaches compared to standard drying protocol at constant operating conditions. The input profiles obtained by offline control lead to a 16% shorter cycle time; however, the lack of feedback during the cycle impedes addressing potential parametric variations and model mismatches. Conversely, in-line control yields a reduction of 13% while allowing careful monitoring of the product status, ensuring a more dependable cycle. In both cases, the visual quality inspection confirms the acceptability of the final product without visible degradation.

SiC Nanoparticles Strengthened Alumina Ceramics Prepared by Extrusion Printing

Extrusion-free-form printing of alumina ceramics has the advantages of low cost, short cycle time, and high customization. However, some problems exist, such as the low solid content of ceramic paste and the unsatisfactory mechanical properties of pure alumina ceramics. In this study, SiC nanoparticles were used as a reinforcement phase added to the alumina ceramic matrix. Methylcellulose is used as the binder in the raw material system. Ammonium polyacrylate is used as a dispersant to change the rheological properties of the slurry and increase the solid content of ceramics. SiC nanoparticle-strengthened alumina ceramics were successfully prepared by the extrusion process. The relative settling height and viscosity of ceramic slurries were characterized. The sintering shrinkage of composite ceramics was tested. The flexural strength, fracture toughness, and hardness of the ceramics were characterized. The strengthening and toughening mechanisms of the composite ceramics were further explained by microscopic morphology analysis. Experimental results show that when the content of the dispersant is 1 wt.%, the rheological properties of the slurry are the best. Maximum measured bending strength (227 MPa) and fracture toughness (5.35 MPa·m1/2) were reached by adding 8 wt% SiC nanoparticles; compared with pure alumina ceramics, flexural strength and fracture toughness increased by 42% and 41%, respectively. This study provides a low-cost and effective method for preparing ceramic composite parts.

Mass spectrometry DDA parameters and global coverage of the metabolome: Spectral molecular networks of momordica cardiospermoides plants.

Molecular networking (MN) has emerged as a key strategy to organize and annotate untargeted tandem mass spectrometry (MS/MS) data generated using either data independent- or dependent acquisition (DIA or DDA). The latter presents a time-efficient approach where full scan (MS1) and MS2 spectra are obtained with shorter cycle times. However, there are limitations related to DDA parameters, some of which are (i) intensity threshold and (ii) collision energy. The former determines ion prioritization for fragmentation, and the latter defines the fragmentation of selected ions. These DDA parameters inevitably determine the coverage and quality of spectral data, which would affect the outputs of MN methods. This study assessed the extent to which the quality of the tandem spectral data relates to MN topology and subsequent implications in the annotation of metabolites and chemical classification relative to the different DDA parameters employed. Herein, characterising the metabolome of Momordica cardiospermoides plants, we employ classical MN performance indicators to investigate the effects of collision energies and intensity thresholds on the topology of generated MN and propagated annotations. We demonstrated that the lowest predefined intensity thresholds and collision energies result in comprehensive molecular networks. Comparatively, higher intensity thresholds and collision energies resulted in fewer MS2 spectra acquisition, subsequently fewer nodes, and a limited exploration of the metabolome through MN. Contributing to ongoing efforts and conversations on improving DDA strategies, this study proposes a framework in which multiple DDA parameters are utilized to increase the coverage of ions acquired and improve the global coverage of MN, propagated annotations, and the chemical classification performed.

Evaluation of Power Consumption in High Efficiency Milling (HEM) of Aluminium 6061

In the machining industry, reducing energy consumption at a maximal material removal rate (MRR) has long been a priority. Using the response surface method, a predictive model has been proposed for the minimal power consumption in side-milling machining. Using response surface method (RSM), the effect of cutting parameters (feed rate, spindle speed, and radial depth of cut) on power consumption was investigated. The results revealed thatfeed rateis the most influential parameter for power consumption. The higher feed rate, the shorter cycle time thus reduce the power consumption. Based on the optimization model, minimum power consumption of 82.38 kW can be achieved at feed rate = 6,000 mm/in, radial depth of cut of 0.3 mm and spindle speed 12,000 rpm.

Handrim Wheelchair Propulsion Technique in Individuals With Spinal Cord Injury With and Without Shoulder Pain: A Cross-sectional Comparison.

The aim of this study was to compare handrim wheelchair propulsion technique between individuals with spinal cord injury with and without shoulder pain. A cross-sectional study including 38 experienced handrim wheelchair users with spinal cord injury was conducted. Participants were divided into the "shoulder pain" ( n = 15) and "no-shoulder pain" ( n = 23) groups using the Local Musculoskeletal Discomfort scale. Kinetic and spatiotemporal aspects of handrim wheelchair propulsion during submaximal exercise on a motor-driven treadmill were analyzed. Data were collected using a measurement wheel instrumented with three-dimensional force sensors. After correction for confounders (time since injury and body height), linear regression analyses showed that the pain group had a 0.30-sec (95% confidence interval, -0.5 to -0.1) shorter cycle time, 0.22-sec (95% confidence interval, -0.4 to -0.1) shorter recovery time, 15.6 degrees (95% confidence interval, -27.4 to -3.8) smaller contact angle, and 8% (95% confidence interval, -15 to 0) lower variability in work per push compared with the no-pain group. Other parameters did not differ between groups. This study indicates that individuals with spinal cord injury who experience shoulder pain propel their handrim wheelchair kinematically differently from individuals with spinal cord injury without shoulder pain. This difference in propulsion technique might be a pain-avoiding mechanism aimed at decreasing shoulder range of motion.

Study on warpage and filling behavior of glass in non-isothermal hot embossing

Non-isothermal hot embossing has great potential in the mass production of glass micro optical components due to the relatively short heating-cooling cycle time. However, warpage was induced by the temperature gradient inside the glass replica during hot embossing, resulting in a deteriorated optical performance. Therefore, it is non-trivial to investigate the effects of process parameters on warping and filling behaviors of glass in non-isothermal hot embossing. Firstly, a high-quality microhole was fabricated on monocrystalline silicon carbide (SiC) mold by focused ion beam (FIB) lithography. By using a novel home-made gravity-assisted hot embossing machine, the geometric information (i.e., warpage and microstructures) on SiC mold was transferred into the surface of N-BK7 glass replica. The experimental results indicate that high embossing temperature enables not only the minimization of warpage but also the enhancement of microstructure replication accuracy. Furthermore, increasing embossing force enhances filling capacity but increases warpage amplitude. Interestingly, fast heating/cooling rates and short embossing time enable a small warpage as well as a high embossing efficiency. By optimizing the process parameters, especially the embossing temperature, a small warpage amplitude of 3 μm and a high transfer ratio of 99.11% were achieved, which can meet the high requirement of precision optical components.

Evaluation of the impact of photoperiod and light intensity on decreasing days to maturity in winter wheat

AbstractThe development and improvement of crop cultivars are necessary to meet the demands of the growing global population. The ability to decrease the generation time is imperative for breeders to achieve higher rates of genetic gain annually. Understanding the way in which photoperiod affects the maturation rate of these crops, including winter wheat (Triticum aestivum L.), is required for decreasing generation time in breeding programs. The effects of prolonged photoperiod and light intensity on winter wheat generation time were studied to determine if photoperiod may contribute to a shortened cycle time. Three winter wheat cultivars (Branson, CFBA1401, and Norstar) and one spring wheat cultivar (AC Carberry) were exposed to four treatments based on the daily light integral (DLI): high light (HL) or low light and photoperiod as follows: 22 h of light and 2 h of dark (22:2) or 16 h of light and 8 h of dark (16:8). Generation time, as measured by days to maturity in the HL22:2 treatment, resulted in a decrease of 8 days or 7% of the total generation time, compared to the control, HL16:8 treatment. Photoperiod itself had a minimal effect on generation time when both DLI and temperature were controlled. An improved understanding of the effects of photoperiod, thermal time, and DLI and their interactions is required prior to implementation in a winter cereal breeding program.

Decarburization in Laser Surface Hardening of AISI 420 Martensitic Stainless Steel.

Decarburization deteriorates the surface mechanical properties of steel. It refers to the loss of carbon from steel's surface when exposed to an open-air environment in elevated-temperature conditions. Despite the short interaction time and fast thermal cycle of the laser surface-hardening process, decarburization may still occur. This paper investigates if decarburization occurs during the laser surface hardening of AISI 420 martensitic stainless steel. For comparison, surface-hardening results and decarburizations in a conventional air furnace-heated hardening process (water-quenched and air-cooled) of the same steel material were also investigated. Decarburization seems to have occurred in the laser surface hardening of AISI 420SS. However, the decarburization might not be significant, as the hardness of the steel's surface was increased more than three times to 675 HV during the laser surface hardening, and the hardness drop due to decarburization was estimated to be only 3% with the decarburization depth of 40 μm. Simulations using ThermoCalc software to get the carbon concentration profiles along the depth for both laser-hardened and furnace-heated samples were also investigated.

Machining of bi-metallic aluminium-grey cast iron engine block – process optimisation by means of FEM

Bi-metallic design concept has been introduced in automotive industries to meet the increasingly tighter standards on carbon emission. Yet, machining of bi-metallic engine blocks is accompanied by several challenges like short tool life and long cycle times. This study presents a novel methodology that combines the concept of experimental design with Finite Element (FE) to optimise the tool performance and enhance the productivity when finish face milling of aluminium-grey cast iron engine blocks. This simulation-assisted approach led to an approximately 32% decrease in machining cycle time as compared to that of a reference cutting condition.

Inflatable architecture. Short critical history of uses in architecture

The pandemic crisis, as a turning point in recent history, has caused existing resources to be mobilized in a short time and triggered the emergence of unique approaches to spatial reorganization. With their formal freedom, unlimited adaptability and short production cycle times, lightweight inflatable or pneumatic structures, which are still in the midst of a technological boom, are an undeniable source of inspiration for today's crisis adaptation. Beyond pragmatic features such as ergonomics, protection and cleanliness, a variety of stylistic approaches can be identified, ranging from small-scale, minimal interventions in interior architecture, to large-scale, urban interventions. The article reviews the sources of inspiration that cross time and space, moving from the utopias of the 1960s to the emergency projects of the 21st century, with the aim of highlighting, through the broad spectrum of solutions, a direction to follow in architecture adapted to crisis solutions. Inflatable structures still fascinate, having the potential to be symbolic in any context.

Alati "unapređenja" i "kontrole" u montaži mikro komponenti - studija slučaja

The process of assembling micro components requires careful planning where precise and reliable data collecting is necessary due to a short production cycle time. After determining the shortages of the current data monitoring system, in this paper, by using the "Improve" and "Control" phases of DMAIC cycle, the development and later testing of a new tool for automatic capture and analysis of data obtained from the machine was done. SWOT analysis was used to establish the production site's and current manufacturing execution system strengths and weaknesses, opportunities and threats, which were then utilized to create the newly developed solution accurate and feasible. A tool calibration data was obtained on 9 machines in automotive company's micro component assembly unit. To confirm the accuracy of the data, a RunAtRate test was done on the machines, and by using hypothesis testing, the initial reliability of the new solution was determined. Further testing and comparison revealed that the newly proposed tool recorded 73-80% greater downtime and 40-50% more defective parts than the previously installed system. Accordingly, the usefulness of the proposed Lean Six SIGMA tool is confirmed, and for periodic accuracy checks and further improvement, it is necessary to apply the PDCA cycle.

Applications and Development of X-ray Inspection Techniques in Battery Cell Production

Demand for lithium-ion battery cells (LIB) for electromobility has risen sharply in recent years. In order to continue to serve this growing market, large-scale production capacities require further expansion and the overall effectiveness of processes must be increased. Effectiveness can be significantly optimized through innovative manufacturing technology and by identifying scrap early in the production chain. To enable these two approaches, it is imperative to quantify safety- and function-critical product features in critical manufacturing steps through appropriate measurement techniques. The overview in this paper on quality control in LIB production illustrates the necessity for improved inspection techniques with X-rays to realize a fast, online measurement of inner features in large-scale cell assembly with short cycle times and to visualize inner product-process interactions for the optimization in electrolyte filling. Therefore, two new inspection techniques are presented that contribute to overcoming the aforementioned challenges through the targeted use of X-rays. First, based on the results of previous experiments in which the X-ray beam directions were deliberately varied, a online coordinate measurement of anode-cathode (AC) overhang was developed using a line detector. Second, a new concept and the results of a continuous 2D visualization of the electrolyte filling process are presented, which can be used in the future to optimize this time-critical process step. By using a X-ray-permeable and portable vacuum chamber it is possible to quantify the influence of process parameters on the distribution of the electrolyte in the LIB.

Optimizing the Banking Service System Using Queue Theory, Fuzzy DEMATEL and TOPSIS Approach: Case Study

Purpose: This paper aimed to improve and optimize the overall performance of the banking service system using queue theory in various activities whilst maximizing profits. Research Methodology: Based on previous literature and interview with related experts, the initial status of the banking system is analyzed as well as the methodologies of queue theory. The data was analyzed to modeling queuing systems for understanding queuing behavior using Wittness Software for simulation. Different queuing strategies will be implemented using the waiting time to find the most efficient solution and the optimized result is concluded. Result: In this paper, the performance of the banking system is investigated and improved by the queuing theory. The sensitive analysis approach will provide new solutions for the optimization of the bank queuing, which could later be implemented for better banking performance. Based on the results obtained, the recommended method produces the best customer satisfaction and maximizes profits. The results of the paper enable decision-makers to obtain useful results with enough knowledge of the behavior of the system. Limitation: This research only described the Iranian bank system. There is different limitation regarded as external factors that varies from one banking system to another and many works are needed to further combat the problems faced by the banking sectors. Contribution: The results are a guideline for managers or decision makers and help them shorten cycle time and to save costs, and resolve problems. It also serves as a useful base for researchers to expand further research concerning the problems of the banking system in other organizations. Keywords: 1. operation system 2. queue theory 3. optimization of the banking system

Triads in Lean Management: Analyzing Buyer–Supplier-Supplier and Buyer–Supplier-Supplier’s Supplier Relationships for Zero-Defect Manufacturing

Many studies on buyer–supplier-supplier triads demonstrate the value of the interactions between three business actors instead of two for identifying triadic collaboration strategies that can lead firms to improve their performance. However, there is little research to date that has explored which specific lean improvements the various types of buyer–supplier-supplier triads lead to. This paper fills this gap. We study an automotive supplier manufacturing company (the buyer) and its seven types of buyer–supplier-supplier triads emerging from the buyers’ attempt to implement zero-defect manufacturing (ZDM) in the production process of a crash management system. The case study shows how a buyer manages their first-tier suppliers through three types of closed buyer–supplier-supplier triads, where all three actors collaborate to work for the common goal of ZDM. The case also shows four additional types of open triads, where the buyer relies on the first-tier supplier to manage the second-tier supplier without directly interacting with the latter. The paper discusses what types of triads in the case study seem to be associated with the buyers’ efforts to achieve the following lean sub-goals of ZDM: full automation, production line flexibility, product flexibility, low cost, low defect rate, short cycle time, and minimum quality control. Finally, we also analyze the role of geographic proximity between the actors in open and closed buyer–supplier-supplier ZDM triads.

Double diaphragm forming simulation for net-shape component using multi-layered biaxial non-crimp fabrics

Compared to autoclave-cured prepreg, liquid composite moulding (LCM) is a cost-effective alternative to produce advanced composites, thanks to the less-expensive intermediate materials, lower capital investment and shorter cycle time. A separate preforming step is typically required within the process chain to convert 2D fabric blanks into complex 3D geometries before moulding. Numerical models are therefore important to ensure near net-shape preforms during the design phase, in order to minimise the material wastage related to preforming. In this study, a microscale finite element (FE) model was employed to assist in determining the ply shape of multi-ply biaxial non-crimp fabrics (NCF) to achieve net-shape preforms made by double diaphragm forming (DDF) using a spar-like geometry. The forming deformation of the NCF was predicted by simulations considering the in-plane stiffness of the NCF. The location of wrinkles was indicated by the simulation using membrane elements. By continuously removing the redundant fabric material making contact with the machine bed and tool surface, net-shape preforms were achieved for the target geometry using single and multiple NCF plies respectively. Compared with the original ply shape, the number of wrinkles was reduced for the net-shape case due to the reduction in the bridging force induced by the contact pairing between fabric-diaphragm assembly and the machine bed.

A Holistic Approach to Cooling System Selection and Injection Molding Process Optimization Based on Non-Dominated Sorting.

This study applied a holistic approach to the problem of controlling the temperature of critical areas of tools using conformal cooling. The entire injection molding process is evaluated at the tool design stage using four criteria, one from each stage of the process cycle, to produce a tool with effective cooling that enables short cycle times and ensures good product quality. Tool manufacturing time and cost, as well as tool life, are considered in the optimization by introducing a novel tool-efficiency index. The multi-objective optimization is based on numerical simulations. The simulation results show that conformal cooling effectively cools the critical area of the tool and provides the shortest cycle times and the lowest warpage, but this comes with a trade-off in the tool-efficiency index. By using the tool-efficiency index with non-dominated sorting, the number of relevant simulation cases could be reduced to six, which greatly simplifies the decision regarding the choice of cooling system and process parameters. Based on the study, a tool with conformal cooling channels was made, and a coolant inlet temperature of 20 °C and a flow rate of 5 L/min for conformal and 7.5-9.5 L/min for conventional cooling channels were selected for production. The simulation results were validated by experimental measurements.

Maintenance robot for remote assembly of protective jackets on live gas risers

Combining high-rise robotics research and polyurethane (PU) repair techniques presents new opportunities and unique challenges for utility pipe maintenance. Aiming at solving the complex pose alignment issue of robots and control PU curing, this paper automates the repair process by assembling protective jackets with PU foam. A wire-hoisted robot was equipped with anchors and a twin-gripper mechanism for workspace definition, along with a manipulator that positioned a pair of mirrored end effectors to perform surface polishing, jacket installation, and PU curing onto the pipe. Consequently, the robot pose was stabilized. The jacket pair was assembled onto the pipe with high precision, yielding high-quality repair, a success rate >96%, short cycle time, and low material wastage. This research may inspire innovative automation approaches for building maintenance, while utility companies can deploy the robot system for sustainable pipe service life.

Solid State Joining of a Cold Rolled Zr-Based Bulk Metallic Glass to a Wrought Aluminum Alloy by Power Ultrasonics.

Ultrasonic metal welding (UMW) enables joining in the solid state at relative low temperatures with short cycle times. This technique is of particular interest for joining metallic glasses to each other or to other materials, because crystallization of the amorphous structure can be prevented due to the low thermal loading and the rapidity of the process. In this work, UMW is applied to join one 1 mm thick sheet of a commercial wrought aluminum alloy (AA5754) and one 0.4 mm thick strip of a commercial Zr-based bulk metallic glass (AMZ4). The introduced heat of the welding process is detected with thermocouples and thermal imaging. To investigate the strength of the joint and the influence on the microstructure, mechanical tensile tests are carried out in combination with scanning electron microscopy and differential scanning calorimetry. The results show that ultrasonic metal welding is a suitable technique to join amorphous bulk metallic glasses to crystalline aluminum alloys. The metallic glass component retains its amorphous structure in the joint, and the joint strength is higher than the strength of the Al sheet. These findings will help to develop future applications of BMG-based multi-material components, including medical tools.

An Analytic Approach for Acoustic Material Testing

Acoustic material testing is well known for quality inspection of metal and composite parts in serial production with short cycle times and a robust performance. It is a referencing as well as a comparative testing method. Preclassified reference parts are required to teach the testing algorithm. The teaching process of an acoustic material testing system (ART) for suitable test criteria has to be done iterative by re-assessment and optimisation to improve the testing characteristics and the hit rate. Common acoustic testing systems are using conventional characteristics like frequency position, damping factor and amplitude monitoring or amplitude attenuation. But this is very often not enough for a reliable testing in consideration of batch or production tolerances. Modern ART systems offer already a choice of intelligent algorithms in combination with characteristics based on pattern recognition like frequency split up, frequency distance relations, multiple frequency peak detection, compensation and more. An additional approach is the evaluation of a complete frequency range instead of individual frequencies. Such characteristic attributes are more known for NVH testing like cumulative or average level, square sum and flatness tolerance. Self-learning test system is taken care with the aid of mathematical pattern recognition processes and automatic re-assessment feedback which will increase the acceptance and reliability of such acoustic material testing systems. Innovative aspects The innovative aspect is the application of pattern recognition techniques which leads to the future implementation of artificial intelligence technologies. With these new approaches, the acoustic testing will become much more usable for e.g. composite materials.

Development of an Epoxy-Based Rapid Tool with Low Vulcanization Energy Consumption Channels for Liquid Silicone Rubber Injection Molding.

Liquid silicone rubber (LSR) parts have some distinct characteristics such as superior heat stability, low-temperature flexibility, aging resistance, and chemical resistance. From an industrial standpoint, the uniform vulcanization temperature of LSR is an important research point. However, the uniformity of the vulcanization temperature of LSR has been limited since the layout of the cartridge heater incorporated in the conventional steel mold does not follow the profile of the mold cavity. Metal additive manufacturing can be used to make LSR injection molds with conformal heating channels and conformal cooling channels simultaneously. However, this method is not suitable for a mold required to develop a new LSR product. In this study, a cost-effective approach was proposed to manufacture an LSR injection mold for the pilot run of a new optical lens. A rapid tool with low vulcanization energy consumption channels was proposed, which was incorporated with both a conformal heating channel (CHC) and conformal cooling channel (CCC) simultaneously. The function of the CHC was to vulcanize the LSR in the cavity uniformly, resulting in a shorter cycle time. The function of the CCC was to keep the LSR in a liquid state for reducing runner waste. It was found that the equation of y = -0.006x3 + 1.2114x2 - 83.221x + 1998.2 with the correlation coefficient of 0.9883 seemed to be an optimum trend equation for predicting the solidification time of a convex lens (y) using the vulcanizing hot water temperature (x). Additionally, the equation of y = -0.002x3 + 0.1329x2 - 1.0857x + 25.4 with the correlation coefficient of 0.9997 seemed to be an optimum prediction equation for the solidification time of a convex lens (y) using the LSR weight (x) since it had the highest correlation coefficient. The solidification time of a convex lens could be reduced by about 28% when a vulcanizing hot water temperature of 70 °C was used in the LSR injection mold with CHC.