Browse
Subjects
Records with Subject: Optimization
1456. LAPSE:2023.2693
Adsorbent Minimization for Removal of Ibuprofen from Water in a Two-Stage Batch Process
February 21, 2023 (v1)
Subject: Optimization
Keywords: adsorbent usage minimization, high removal capacity, pharmaceutical adsorption, two-stage batch adsorber optimization, waste date stone derived carbon
Pharmaceutical products in water, also known as personal pharmaceutical products or PCPPs, are developing contaminants that have the potential to impair human health and the environment in a variety of ecosystems. In this work, waste date stones, a waste product obtained from the seedless dates manufacturing industry, were used to make acid-activated carbon. This material has been utilized to extract the medicinal component ibuprofen from water, with a high adsorption capacity of 126 mg ibuprofen per g of waste date stone-generated activated carbon. A design study was conducted to minimize the amount of activated carbon required, utilizing a two-stage batch adsorption system to optimize the usage of the activated carbon. To test the model and compare the quantities of adsorbent required in the two-stage and single-stage systems under various conditions, several variables were entered into the design model.
1457. LAPSE:2023.2688
Macro-Batch and Continuously Operated Microfluidic Emulsification—Differences, Similarities and Optimization
February 21, 2023 (v1)
Subject: Optimization
Keywords: average Feret diameter, high shear mixing, microfluidics, PEG emulsions, zeta potential
In this work, the emulsification of oil-in-water two-phase systems with three emulsifiers (PEG1500, 6000 and 20000) was studied in a batch macro system and in a continuously operated microfluidic system. The effect of emulsifier concentration, oil concentration and mixing rate on zeta potential and average Feret diameter was analyzed for the macro-batch system, while the effect of emulsifier concentration, oil concentration and total flow rate on zeta potential and average Feret diameter was analyzed for the microfluidic system. The emulsions prepared in batch system were more stable, had smaller droplet diameter but higher values of polydispersity index (PDI) compared to those prepared by continuous method. In both cases, batch and continuous, the use of PEG with higher molecular weight resulted in emulsions with lower zeta potential values. In batch emulsification, all three optimization parameters (emulsifier concentration, oil concentration and mixing rate) had a significant influe... [more]
1458. LAPSE:2023.2671
Targeting on Different Characteristic Continuous Variables in Process Transition for Ethylene Column with Wide-Range Feed Fluctuation
February 21, 2023 (v1)
Subject: Optimization
Keywords: different characteristic continuous variables, ethylene column, parameter optimization, process transition, wide-range feed fluctuation
For the study of the transition strategies of continuous chemical processes, both continuity and dynamic characteristics in the physical sense are critical. The continuous transition strategy has a higher information density and can describe the real situation as closely as possible. In addition, the accuracy of the dynamic characteristics is necessary because the process transition is the study of the dynamic system processes. However, existing transition strategies have certain shortcomings. Dynamic optimization can obtain transition strategies with different characteristics but no physical meaning and a frequency domain-based analytical approach can acquire a continuous transition strategy with physical meaning, but its dynamic characteristics are the same. Therefore, by integrating the advantages of the existing strategies, a new transition strategy has been presented, which possesses different dynamic characteristics and continuity synchronous with physical significance. When proc... [more]
1459. LAPSE:2023.2607
Audio Compensation with Cascade Biquad Filters for Feedback Active Noise Control Headphones
February 21, 2023 (v1)
Subject: Optimization
Keywords: active noise control, audio compensation, feedback control, headphones, optimization process
In active noise control (ANC) headphones, the audio signal is modified together with the primary noise if a feedback controller is used. Although this problem can be alleviated with an FIR model of the secondary path, practical implementations are usually restricted by its computational complexity. In this paper, cascade biquad filters are used to compensate for the modification of the audio system. Instead of using classical identification methods with an IIR model, the audio compensation problem is fixed through an optimization process. An objective function evaluating the comprehensive compensation performance is proposed, whose minimum value is obtained using the differential evolution (DE) algorithm. Simulations and experiments are carried out, whose results validate the effectiveness and efficiency of the proposed optimization method. The averaged compensation error can be reduced to about 0.5 dB with only two to five biquad filters.
1460. LAPSE:2023.2569
A Combined Model Based on the Social Cognitive Optimization Algorithm for Wind Speed Forecasting
February 21, 2023 (v1)
Subject: Optimization
Keywords: ELM, Elman, LSTM, SCO, wind speed forecasting
The use of wind power generation can reduce the pollution in the environment and solve the problem of power shortages on offshore islands, grasslands, pastoral areas, mountain areas, and highlands. Wind speed forecasting plays a significant role in wind farms. It can improve economic and social benefits and make an operation schedule for wind turbines on large wind farms. This paper proposes a combined model based on the existing artificial neural network algorithms for wind speed forecasting at different heights. We first use the wavelet threshold method with the original wind speed dataset for noise reduction. After that, the three artificial neural networks, extreme learning machine (ELM), Elman neural network, and Long Short-term Memory (LSTM) neural network, are applied for wind speed forecasting. In addition, the variance reciprocal method and social cognitive optimization (SCO) algorithm are used to optimize the weight coefficients of the combined model. In order to evaluate the... [more]
1461. LAPSE:2023.2547
Heat-Integration of Solar-Heated Membrane Distillation and Fuel Cell for Desalination System Based on the Dynamic Optimization Approach
February 21, 2023 (v1)
Subject: Optimization
Keywords: dynamic optimization, heat integration, hybrid systems, PEMFC, solar-heated DCMD
The heat integration feasibility of the proton exchange membrane fuel cell (PEMFC) coupled with the solar-heated direct contact membrane distillation (DCMD) module is evaluated in this study. The additional waste heat from the PEMFC increases the DCMD system’s ability to produce fresh water and electricity. Two systems units to be assessed mainly include a flat plate solar collector, a heat storage tank with an internal heat exchanger, and the DCMD module with and without the PEMFC module. The importance of daily operation continuity is emphasized through a preliminary dynamic simulation and proper sizing of the solar-heated DCMD distillation. Sensitivity analysis is implemented to analyze the relationship between the essential variables and the daily freshwater production. The design variables of both configurations are rigorously optimized in terms of minimum unit production cost (UPC). The proposed heat integration feasibility is evaluated to obtain critical insights on the design s... [more]
1462. LAPSE:2023.2488
Logistics Service Provider Evaluation and Selection: Hybrid SERVQUAL−FAHP−TOPSIS Model
February 21, 2023 (v1)
Subject: Optimization
Keywords: fuzzy theory, logistics services provider, MCDM, Optimization
Production and business enterprises are aiming to improve their logistics activities in order to increase competitiveness. Therefore, the criteria and decision support models for selecting logistics service providers are significant to businesses. Fuzzy theory has been applied to almost all industrial engineering fields, such as decision making, operations research, quality control, project scheduling and many more. In this research, the authors combined fuzzy theory and a Multicriteria Decision Making (MCDM) model for the evaluation and selection of potential third-party logistics (3PL) providers. The goal is to take the advantages of these approaches and allow for more accurate and balanced (symmetric) decision making through their integration. The main contribution of this study is that it develops a complete approach to assessing the quality of the logistics service industry. The combined method of the SERVQUAL and FAHP−TOPSIS models not only provides reasonable results, but it als... [more]
1463. LAPSE:2023.2481
Interval-Valued Pythagorean Fuzzy Similarity Measure-Based Complex Proportional Assessment Method for Waste-to-Energy Technology Selection
February 21, 2023 (v1)
Subject: Optimization
Keywords: complex proportional assessment, interval-valued Pythagorean fuzzy set, MCDM, municipal solid waste, waste-to-energy
This study introduces an integrated decision-making methodology to choose the best “waste-to-energy (WTE)” technology for “municipal solid waste (MSW)” treatment under the “interval-valued Pythagorean fuzzy sets (IPFSs)”. In this line, first, a new similarity measure is developed for IPFSs. To show the utility of the developed similarity measure, a comparison is presented with some extant similarity measures. Next, a weighting procedure based on the presented similarity measures is proposed to obtain the criteria weight. Second, an integrated approach called the “interval-valued Pythagorean fuzzy-complex proportional assessment (IPF-COPRAS)” is introduced using the similarity measure, linear programming model and the “complex proportional assessment (COPRAS)” method. Furthermore, a case study of WTE technologies selection for MSW treatment is taken to illustrate the applicability and usefulness of the presented IPF-COPRAS method. The comparative study is made to show the strength and s... [more]
1464. LAPSE:2023.2456
Real-Time Optimization of Wastewater Treatment Plants via Constraint Adaptation
February 21, 2023 (v1)
Subject: Optimization
Keywords: BSM1, constraint adaptation, fast constraint adaptation, real-time optimization, WWTP
An important requirement of wastewater treatment plants (WWTPs) is compliance with the local regulations on effluent discharge, which are going to become more stringent in the future. The operation of WWTPs exhibits a trade-off between operational cost and effluent quality, which provides a scope for optimization. Process optimization is usually done by optimizing a model of the process. However, due to inevitable plant−model mismatch, the computed optimal solution is usually not optimal for the plant. This study represents the first attempt to handle plant−model mismatch via constraint adaptation (CA) for the real-time optimization of WWTPs. In this simulation study, the “plant” is a model adopted from the BSM1 benchmark, while a reduced-order “model” is used for making predictions and computing the optimal inputs. A first implementation uses steady-state measurements of the plant constraints to adjust the model in the optimization framework. A fast CA technique is also proposed, whic... [more]
1465. LAPSE:2023.2368
Performing Multi-Objective Optimization Alongside Dimension Reduction to Determine Number of Clusters
February 21, 2023 (v1)
Subject: Optimization
Keywords: data clustering, dimension reduction, multi-objective optimization, Pareto solution
One of the consequences of the widespread automation of manufacturing operations has been the proliferation and availability of historical databases that can be exploited by analytical methods to improve process understanding. Data science tools such as dimension reduction and clustering are among many such approaches that can aid in the identification of unique process features and patterns that can be associated with faulty states. However, determining the number of such states still requires significant engineering knowledge and insight. In this study, a new unsupervised method is proposed that reveals the number of classes in a data set. The method utilizes a variety of dimension reduction techniques to create projections of a data set and performs multiple clustering operations on the lower-dimensional data as well as the original data. The relevant internal clustering metrics are incorporated into a multi-objective optimization problem to determine the solutions that simultaneous... [more]
1466. LAPSE:2023.2367
The Effects of Logistics Websites’ Technical Factors on the Optimization of Digital Marketing Strategies and Corporate Brand Name
February 21, 2023 (v1)
Subject: Optimization
Keywords: advertising, Big Data, brand name, competitive advantage, digital marketing, logistics, predictive model, SEM, user engagement, web analytics
In a world overwhelmed with unstructured information, logistics companies increasingly depend on their websites to acquire new customers and maintain existing ones. Following this rationale, a series of technical elements may set the ground for differentiating one logistics website from another. Nevertheless, a suitable digital marketing strategy should be adopted in order to build competitive advantage. In this paper, the authors attempt to respond by implementing an innovative methodology building on web analytics and big data. The first phase of the research collects data for 180 days from 7 world-leading logistics companies. The second phase presents the statistical analysis of the gathered data, including regression, correlations, and descriptive statistics. Subsequently, Fuzzy Cognitive Mapping (FCM) was employed to illustrate the cause-and-effect links among the metrics in question. Finally, a predictive simulation model is developed to show the intercorrelation among the metric... [more]
1467. LAPSE:2023.2343
Power Parametric Optimization of an Electro-Hydraulic Integrated Drive System for Power-Carrying Vehicles Based on the Taguchi Method
February 21, 2023 (v1)
Subject: Optimization
Keywords: electric vehicles, electro-hydraulic ratio, electro-mechanical-hydraulic, Optimization, Taguchi method
Focused on the troubles and defects introduced by the traditional single form of electric vehicle transmission, this paper proposes an electro-hydraulic power coupled electric vehicle based on the working principle of an electro-hydraulic power integrated drive system for light-duty cargo vehicles. The integration of the planetary row into the drive system allows the interconversion of mechanical, electrical, and hydraulic energy. By describing the system structure and composition, several working conditions during automobile driving are proposed, and the working principle of every circumstance is introduced. Simultaneously, the article determines the preliminary optimal ratio with the battery’s state of charge (SOC) as the constraint. Then, the orthogonal test matrix of electro-hydraulic ratios and speed thresholds for each operating condition is established according to Taguchi’s method. The impact of each optimized parameter on the motor torque and hydraulic torque as well as the SO... [more]
1468. LAPSE:2023.2339
Solutions of Feature and Hyperparameter Model Selection in the Intelligent Manufacturing
February 21, 2023 (v1)
Subject: Optimization
Keywords: feature selection, hyperparameter optimization, intelligent manufacturing, milling tool wear, SHAP
In the era of Industry 4.0, numerous AI technologies have been widely applied. However, implementation of the AI technology requires observation, analysis, and pre-processing of the obtained data, which takes up 60−90% of total time after data collection. Next, sensors and features are selected. Finally, the AI algorithms are used for clustering or classification. Despite the completion of data pre-processing, the subsequent feature selection and hyperparameter tuning in the AI model affect the sensitivity, accuracy, and robustness of the system. In this study, two novel approaches of sensor and feature selecting system, and hyperparameter tuning mechanisms are proposed. In the sensor and feature selecting system, the Shapley Additive ExPlanations model is used to calculate the contribution of individual features or sensors and to make the black-box AI model transparent, whereas, in the hyperparameter tuning mechanism, Hyperopt is used for tuning to improve model performance. Implement... [more]
1469. LAPSE:2023.2301
Feasibility of a Complex Optimized Process for the Treatment of Patients Receiving Hip and Knee Endoprostheses in Most Different Settings in Germany—Results from the PROMISE Trial
February 21, 2023 (v1)
Subject: Optimization
Keywords: ERAS, feasibility, hip replacement, knee replacement, process optimization
Background: While there is evidence on the effectiveness of optimized treatment processes for patients receiving hip and knee endoprostheses, feasibility in various settings has not been adequately investigated. The multicenter PROMISE Trial (Process optimization by interdisciplinary and cross-sectoral care using the example of patients with hip and knee prostheses) was set up to fill this gap. Methods: A complex optimized process was implemented in three German hospitals offering different levels of care and five cooperating rehabilitation centers. For the feasibility question, data on 19 parameters characterizing the defined process were collected. The extent of cross-sectoral collaboration was a special focus. Results: The data show, for almost all parameters in all facilities, an implementation rate of more than 80% with missing data below 5%, n = 1887 study participants. A total of 96.8% attended a rehabilitation program, and for 29.2% rehabilitation took place in a PROMISE-collab... [more]
1470. LAPSE:2023.2241
Selection of Supply Chain Sustainability Management System by Fuzzy Additive Preference Programming Method
February 21, 2023 (v1)
Subject: Optimization
Keywords: analytic hierarchical process, decision analysis, fuzzy linear programming, multiple criteria analysis, sustainability management systems
A selection of suitable sustainability management systems (SMS) is a major part of supply chain strategies to create a competitive advantage, reduce total costs, and manage long-term sustainability. A framework and method for prioritizing supply chain SMSs are presented in this research. Analytic hierarchy process (AHP) is the most common method for alternative selection in multi-criteria decision-making (MCDM). However, complex information is mixed with ambiguity and uncertainty, which makes decision makers unable to use precise or crisp numbers, so fuzzy numbers are presented to remedy this difficulty. Therefore, this research proposes a fuzzy additive preference programming (FAPP) to select the optimum SMS for a supply chain. FAPP method can produce the unique normalized optimal priority vector of fuzzy pairwise comparison matrices for SMS selection effectively with linear constraints. The additive linear constraints can eliminate the weaknesses of existing methods and equalize the... [more]
1471. LAPSE:2023.2240
Surrogate-Assisted Multi-Objective Optimization of a Liquid Oxygen Vacuum Subcooling System Based on Ejector and Liquid Ring Pump
February 21, 2023 (v1)
Subject: Optimization
Keywords: cryogenic aerospace vehicle, many-objective optimization, Surrogate Model, vacuum subcooling system
As an important combustion aid for aerospace vehicles, subcooled liquid oxygen of high density can be used to increase loading capacity of a spacecraft. Providing a large amount of cryogenic propellant in a short time with a strict energy consumption limitation is a challenge in the design of the fuel filling system. The authors proposed a vacuumed subcooling system combined with an ejector and liquid ring pump to vacuum a liquid oxygen tank and obtain subcooled liquid oxygen. After the liquid oxygen tank is vacuumed to an intermediate pressure by the ejector, it is further vacuumed to 10 kPa using the liquid ring pump. The infinitesimal method was used to simulate the thermodynamic processes involved. Taking the ejector working fluid mass flow rate, jet pressure, intermediate pressure, initial tank liquid level, and liquid ring pump speed as optimizing variables, optimization was conducted to determine the optimal vacuuming time, remaining liquid level in the tank, pumping speed diffe... [more]
1472. LAPSE:2023.2227
Application of MEREC in Multi-Criteria Selection of Optimal Spray-Painting Robot
February 21, 2023 (v1)
Subject: Optimization
Keywords: compromise solution, multi-criteria, Optimization, ranking, robot selection
Robots are being increasingly utilized for various operations in industrial and household applications. One such application is for spray painting, wherein atomized paint particles are sprayed on a surface to coat the surface with paint. As there are different models of robots available for the job, it becomes crucial to select the best among them. Multi-criteria decision-making (MCDM) techniques are widely used in various fields to tackle selection problems where there are many conflicting criteria and several alternatives. This work focuses on selecting the best robot among twelve alternatives based on seven criteria, among which payload, speed, and reach are beneficial criteria while mechanical weight, repeatability, cost, and power consumption are cost criteria. Five MCDM techniques, namely combination distance-based assessment (CODAS), complex proportional assessment (COPRAS), combined compromise solution (CoCoSo), multi-attributive border approximation area comparison (MABAC), an... [more]
1473. LAPSE:2023.2190
Optimization of Sporulation Conditions for Bacillus subtilis BSNK-5
February 21, 2023 (v1)
Subject: Optimization
Keywords: Bacillus subtilis, fermentation medium, Optimization, sporulation rate
spores have important biological applications; however, high spore-cell densities and sporulation efficiencies in fermentation is poorly reported. This study systematically analyzed the spore densities and formation efficiency of B. subtilis BSNK-5 in different culture substrates. A response surface regression equation was established based on the results of single factor and Box−Behnken experimental designs. The optimal medium formulation, as predicted from the equation, consisted of soluble starch at 3 g·L−1, soybean flour at 12 g·L−1, and MgSO4 at 5 g·L−1. The spore yield reached 2.43 × 109 CFU·mL−1, and the sporulation rate was 83.3%, which was nearly three times higher than before optimization using an optimized medium at 36 °C and 200 rpm for 60 h.
1474. LAPSE:2023.2134
Optimization of the Subcritical Butane Extraction of Tung Oil and Its Mechanism Analysis
February 21, 2023 (v1)
Subject: Optimization
Keywords: Extraction, response surface method, subcritical, tung oil
Tung oil is an important dry grease. In order to overcome the deficiencies of traditional processes in oil production, the preparation of tung oil was carried out by the butane-subcritical method. A response surface optimization experiment was carried out based on Design-Expert software, and the best process parameters were obtained. The extraction temperature was 42.98 °C, the extraction time was 43.77 min, the particle size of the raw material was 38.88 mesh, and the oil yield of tung oil under this condition reached 67.437%. The fatty acid composition of tung oil was analyzed by Gas Chromatography-Mass Spectrometry (GC-MS): the content of α-oleostearic acid was 74.99%, linoleic acid content was 8.83%, oleic acid content was 7.42%, palmitic acid content was 2.02%, and stearic acid content was 4.35%. Through the analysis of the oil sample obtained, five indicators showed that the process of obtaining oil products met the requirements of the national standard. By simulating the subcrit... [more]
1475. LAPSE:2023.2127
Mechanical Behavior and Optimization of Tubing String with Expansion Joint during Fracturing in HTUHP Wells
February 21, 2023 (v1)
Subject: Optimization
Keywords: expansion joint, fracturing, packer, tubing string, ultra-high pressure well
During the formation testing in high-temperature (HT) and ultra-high-pressure (UHP) wells, one of the major challenges is packer failure in the downhole caused by high-rate fracturing. In such a case, the axial shrinkage trend of the tubing string could be caused by the sudden drop in temperature, but the actual axial length of the tubing string would not change because of the constraints at wellhead and packer. Therefore, this could lead to the upward pull-out of the packer that is due to excessive load from the tubing string. This out-of-control downhole pressure often leads to irreversible consequences, even well abandonment. An expansion joint, as a movable splicer, has the characteristic of mitigating packer load, which can theoretically enhance packer safety. To study the protective effect of an expansion joint on the packer quantitatively, the microscopic characteristics and macroscopic properties of the tubing material (13Cr110) are obtained through experimental tests. Moreover... [more]
1476. LAPSE:2023.2115
Production, Optimization, and Partial Purification of Alkali-Thermotolerant Proteases from Newly Isolated Bacillus subtilis S1 and Bacillus amyloliquefaciens KSM12
February 21, 2023 (v1)
Subject: Optimization
Keywords: alkali tolerance, Bacillus amyloliquefaciens, Bacillus subtilis, halotolerant, Optimization, partial purification, proteases
Proteases that can remain active under extreme conditions such as high temperature, pH, and salt concentration are widely applicable in the commercial sector. The majority of the proteases are rendered useless under harsh conditions in industries. Therefore, there is a need to search for new proteases that can tolerate and function in harsh conditions, thus improving their commercial value. In this study, 142 bacterial isolates were isolated from diverse alkaline soil habitats. The two highest protease-producing bacterial isolates were identified as Bacillus subtilis S1 and Bacillus amyloliquefaciens KSM12, respectively, based on 16S rRNA sequencing. Optimal protease production was detected at pH 8, 37 °C, 48 h, 5% (w/v) NaCl for Bacillus subtilis S1 (99.8 U/mL) and pH 9, 37 °C, 72 h, 10% (w/v) NaCl for Bacillus amyloliquefaciens KSM12 (94.6 U/mL). The molecular weight of these partially purified proteases was then assessed on SDS-PAGE (17 kDa for Bacillus subtilis S1 and 65 kDa for Ba... [more]
1477. LAPSE:2023.2096
Determination of Gas Extraction Borehole Parameters in Fractured Zone on ‘Borehole in Place of Roadway’ Based on RSM-GRA-GA
February 21, 2023 (v1)
Subject: Optimization
Keywords: borehole layout optimization, gas excavation, genetic algorithm (GA), gray relational analysis (GRA), response surface methodology (RSM)
Large-diameter gas extraction borehole is considered an effective method by which to realize coal mine methane exploitation and outburst prevention. Efficient gas extraction can be achieved by selecting the right borehole parameters. In this paper, by comparing several conventional objective weighting methods, the PCA was used to assign the weights to the research indices, the optimization objective was reduced from multi-dimensional to one-dimensional with the help of the gray correlation analysis. The study of gas extraction effect under different borehole parameters based on the response surface model. Numerical simulations were used to analyze the mixed volume of gas extraction, the pure volume of extraction and the concentration in the upper corner after extraction under different schemes. Finally, a genetic algorithm degree model was used to solve the solution and determine the optimal arrangement of borehole parameters. The study shows that (1) the weight shares of borehole stra... [more]
1478. LAPSE:2023.2082
A Novel Exponential-Weighted Method of the Antlion Optimization Algorithm for Improving the Convergence Rate
February 21, 2023 (v1)
Subject: Optimization
Keywords: antlion optimization, metaheuristic, Particle Swarm Optimization
The antlion optimization algorithm (ALO) is one of the most effective algorithms to solve combinatorial optimization problems, but it has some disadvantages, such as a long runtime. As a result, this problem impedes decision makers. In addition, due to the nature of the problem, the speed of convergence is a critical factor. As the size of the problem dimension grows, the convergence speed of the optimizer becomes increasingly significant. Many modified versions of the ALO have been developed in the past. Nevertheless, there are only a few research articles that discuss better boundary strategies that can increase the diversity of ants walking around an antlion to accelerate convergence. A novel exponential-weighted antlion optimization algorithm (EALO) is proposed in this paper to address slow convergence rates. The algorithm uses exponential functions and a random number in the interval 0, 1 to increase the diversity of the ant’s random walks. It has been demonstrated that by optimiz... [more]
1479. LAPSE:2023.2055
Lean Optimization Techniques for Improvement of Production Flows and Logistics Management: The Case Study of a Fruits Distribution Center
February 21, 2023 (v1)
Subject: Optimization
Keywords: 5S, agribusiness, cold storage management, endogenous fruits, Kaizen, lean tools, optimization of the production flow, peaches, Value Stream Mapping
The organizations of horticultural producers and, particularly, those that deal with extremely perishable endogenous fruits, such as peaches and cherries, have a greater need to optimize production flows and processes. A particularity of the horticultural industry is the short shelf life of raw materials and the seasonality of products. In this paper, optimization techniques are used to improve the production flows and the management of cold storage and distribution in a fruit central. The application of Lean tools allowed reducing the cycle time by 4.37 min and the lead time by 7.10 min of the whole process, i.e., a reduction of 35.5% and 10.6% of the cycle time and lead time, respectively, excluding the cold conservation operation. The study shows that it is possible to reduce, or even eliminate, waste throughout the process, reduce unnecessary movement, adapt the layout, maximize workspace, and level stocks, as well as greater supplier involvement in a continuous improvement approac... [more]
1480. LAPSE:2023.1989
Exploratory Research on Drainage Structure of Highway Tunnel Based on Reducing the Risk of Crystallization Blockage
February 21, 2023 (v1)
Subject: Optimization
Keywords: crystal blockage, drainage system, highway tunnel, lining disease, structure optimization
Crystal blockages of tunnel drainage systems severely undermine the tunnel lining structure and operation safety. In order to reduce the risk of crystal blockages of tunnel drainage systems, the distribution of highway tunnel defects was identified through a field survey, indoor test, and literature analysis, and an optimization method of tunnel drainage structures was proposed. The research suggested the following: (1) Lining water leakage and construction joint water leakage were the most common defects in the tunnel drainage system of Renhua−Xinfeng Expressway and Yingde−Huaiji Expressway in Guangdong Province, accounting for 60% and 32% of total defects, respectively. The number of defects that occurred in the drainage system of the tunnel was larger in the granite formation, with the number of road seepage and inspection chamber crystallization incidents reaching 2.5/km and 2.8/km, respectively. (2) The groundwater was mainly alkaline with a pH value of 8~12, Ca2+ (107 mg/L) was t... [more]
[Show All Subjects]
[0.09 s]

