Handling Cost Research Articles

A practical kinetic model for polyvinyl chloride polymerization in batch reactors

Vinyl chloride monomer plays a significant contribution to the chemical industry, serving as a fundamental component for the synthesis of polyvinyl chloride (PVC). This material is distinguished as one of the most extensively manufactured polymers worldwide, finding wide application due to its physical properties, providing good durability, affordable cost, and ease of handling. Although certain mathematical models can be found in literature, implementing the multiphase model with kinetic and diffusive effects demands a considerable set of adjustable parameters, making it challenging to reproduce in industrial sites. In contrast, this study describes the dynamic process of vinyl chloride (VC) polymerization by suspension in a batch reactor to produce PVC. The proposed approach considers a simplified yet robust model that requires fewer adjustable parameters, enabling easier implementation and corroborating with experimental data from the literature. By solving systems of algebraic and differential equations, the proposed model accurately reproduces experimental data for the conversion of VC to PVC, specifically for the initiators PW-40 and AIBN. Additionally, the model delivers superior results compared to those obtained using Aspen® Plus PVC module, a commercial platform widely employed in the industry for polymerization process modeling. These improvements are achieved without introducing excessive complexity, making the model a practical and efficient tool for industrial applications, such as the modeling and optimization of PVC reactors.

IMPROVEMENT OF WAREHOUSE TECHNOLOGY IN INTERNATIONAL FREIGHT TRANSPORTATION

The article analyzes the existing methods of building cargo handling technologies in warehouses. The chosen topic is quite relevant, since the use of outdated warehouse infrastructure and the use of outdated mechanization equipment in most cases, the operation of warehousing facilities according to outdated transport and technological schemes in the processing of goods in warehouses; the absence or insufficient use of modern information systems for planning, organizing, controlling and accounting for warehouse operations; lead to significant financial losses. To address the issues related to the technological processing of goods in warehouses, the author proposes a methodology for developing and implementing a technology for determining the rational number of new highly maneuverable and energy-efficient machines. Modern requirements for warehouse operations necessitate the development and implementation of new innovative vehicles that will increase the productivity of warehouse operations by increasing the level of maneuverability and productivity of such vehicles. As a result of the calculations, it was determined that the application of the proposed approach to determining the rational number of new highly maneuverable and energy-efficient machines will reduce the cost of technological cargo handling. When handling the maximum amount of cargo arriving at the warehouse, the total cost of handling such cargo using the proposed mechanisms will be less than when using existing forklifts. When implementing the developed methodology for determining the rational number of mechanisms for performing loading and unloading operations during the technological processing of goods in warehouses, it is possible to obtain a significant economic effect. Under certain conditions of technological handling of goods in warehouses, it is advisable to use simulation modeling of the processes included in the technological schemes of cargo handling. In this case, it is necessary to take into account the external influence of various factors that can lead to significant disruptions in the warehouse.

A Modified Simulated Annealing and Enhanced Harmony Search Algorithms for the Continuous Facility Layout Problem (CFLP)

This paper focuses on solving the Continuous Facility Layout Problem (CFLP), which aims to minimize material handling costs by strategically placing facilities in a known or unknown area. The objective is to find optimal or near-optimal facility arrangements while adhering to non-overlapping and spatial constraints, thus enhancing the efficiency of production systems. The study addresses various layout scenarios, including single-row facility layout (with and without clearance), continuous layout, and unequal-area facility layout problems. To achieve this, the authors propose a mixed-integer nonlinear programming (MINLP) model tailored for continuous layouts. Two meta-heuristic algorithms are developed to optimize this model: a hybrid Simulated Annealing-Genetic Algorithm (SA-GA), which leverages genetic crossover operations, and an Enhanced Harmony Search Algorithm (EHSA), featuring dynamic parameters and a novel improvisation technique. The proposed methods provide flexible and efficient solutions for both small and large-scale layout problems, offering decision-makers practical tools for real-world applications.

A modified adaptive large neighborhood search algorithm for solving the multi-port continuous berth allocation problem with vessel speed optimization

Despite its fast-growing popularity in maritime transportation, container shipping is still fraught with risks and uncertainties with its complex operating environments. This paper studies the multi-port continuous berth allocation problem with speed optimization (MCBAP). In the MCBAP, vessels visit multiple ports sequentially, and the problem aims at minimizing the sum of vessel sailing cost, waiting cost, delay cost and port handling cost, while satisfying various constraints related to vessel sailing and berthing. A mixed integer linear programming (MILP) model for MCBAP is formulated, and a modified adaptive large neighborhood search (MALNS) algorithm is proposed for solving large-scale MCBAPs. In the MALNS, an efficient initial solution generation strategy is developed, and a series of neighborhood solution generation operators are proposed. Finally, the proposed MILP model and MALNS algorithm are tested on a range of MCBAP instances. The numerical results demonstrate that the MILP model can be solved to optimality with CPLEX, and the MALNS can efficiently solve instances at various scales. In addition, sensitivity analyses on fuel prices and vessel design speeds (the planned maximum speeds) are performed, and management insights have been provided.

AI Based Chatbots for Mental Health Care: A Systematic Review

Medicinal utilization of Expert systems for psychological resilience maintenance have proficient a accelerated float in the spent a small number of years. AI empowered chatbot shareware and administration have been supervising fundamental therapeutical hospitalization that were beforehand unique feasible from master and skilled medicare executives. Such resources, which orbit from “essential psychologist” to “community cybermens” in mental health, attempt to enhance serving production and cost handling, as well as gathering the mental health needs of unprotected and disadvantaged citizenery. Nevertheless, there is still a substantial gap between recent progress in AI mental health and the widespread use of these solutions by healthcare exponents in therapeutic settings. Furthermore, therapy are recurrently developed without clear ethical proceedings. While AI-enabled solutions show promise in the realm of mental health, further research is needed to address the ethical and communal aspects of these technologies, as well as to establish efficient exploration and therapeutic practices in this fresh sector.

High-Sensitivity RT-LAMP for Molecular Detection of O'nyong-nyong (Alphavirus onyong).

Mosquitoes serve as vectors for many arthropod-borne viruses (arboviruses) that are responsible for millions of human infections and thousands of deaths each year. Among these arboviruses, O'nyong-nyong virus (ONNV) is an African alphavirus mainly transmitted by Anopheles mosquitoes. ONNV can be detected through serological or molecular tests, the first showing cross-reactivity to co-circulating alphaviruses and requiring technically demanding confirmation, while the latter, usually based on real-time PCR, are costly and demand specific equipment. Isothermal amplification approaches, such as Loop-Mediated Isothermal Amplification (LAMP), should therefore provide a cost-effective, sensitive, and specific alternative for virus detection, suitable for the resource-limited regions where ONNV circulates up to the present time. Here, we describe the development and optimization of a rapid and highly sensitive (10 pfu/reaction) RT-LAMP assay for ONNV detection. Additionally, we demonstrate that it is possible to bypass the RNA extraction step, reducing sample handling time and costs. The final RT-LAMPONNV is a promising field detection tool for ONNV, enabling a better understanding of its impact and serving as a point-of-care diagnostic method.

Green Analytical Method for Perfluorocarboxylic Acids (PFCAs) in Water of Stir Bar Sorptive Extraction Coupled with Thermal Desorption–Gas Chromatography—Mass Spectroscopy

Perfluoroalkyl carboxylic acids (PFCAs) are a significant group of per- and polyfluoroalkyl substances (PFASs). They are persistent organic chemicals manufactured for their resistance to heat, water, and stains. PFCAs are ubiquitous in the environment, particularly in surface water and wastewater, because they are widely used in everyday consumer products. This contamination poses a risk to drinking water supplies and human health, necessitating sensitive and effective analytical methods. Traditional liquid chromatography–tandem mass spectrometry (LC-MS/MS) is commonly used but involves complex sample handling and high costs. In this study, we developed an enhanced stir bar sorptive extraction (SBSE) method coupled with thermal desorption–gas chromatography–mass spectrometry (TD-GC-MS) for the analysis of PFCAs in water. This method demonstrates linearity, with R2 values from 0.9892 to 0.9988, and low limits of detection (LOD) between 21.17 ng/L and 73.96 ng/L. Recovery rates varied from 47 to 97%, suggesting efficient extraction. Compared to traditional methods, the developed SBSE technique requires only a 1 mL sample volume and minimal amounts of solvents, enhancing eco-friendliness and reducing potential contamination and handling errors. This method also demonstrated good precision and robustness across various water matrices. Overall, the developed method offers a precise, eco-friendly, and reliable approach for analyzing PFCAs in diverse water samples.

Morphological characteristics of activated sludge recovered from biological reactors impact on the energy requirement for centrifugal dewatering

The effect of sludge dewatering on handling and transport costs as well as the impact of various parameters like sludge characteristics, the used dewatering equipment and the adopted specific operating conditions, on the efficiency of this step, were considered in the present study. The influence of a laboratory-scale centrifugation for dewatering activated sludge (AS) was also investigated. Additionally, models to describe the relationships between independent variables like centrifugation speed, AS volume and fixed time and dependent variables like the percentage of solid cake (% GS). The used approach was based on the response surface methodology (RSM) along with a central composite design experiment, considering three distinct types of AS: healthy (BS), partially bulking (BF), and deflocculated (BD) sludges. The morphological characteristics of the sludge do have an effect on the operating conditions for the centrifugation, hence the energy consumption for a desired dewatering level. For the case of BS sludge, a centrifugation at 2600 rpm for 10 min, using a 10.3 mL plug, led to a solid cake of 12.65 %, whereas for BD sludge, with a higher centrifugation at 3000 rpm for 17.30 min and a smaller plug volume (8 mL) led to 6.82 %, roughly half of the previous percentage.

A Novel Approach for Material Handling-Driven Facility Layout

Material handling is a widely used process in manufacturing and is generally considered a non-value-added process. The Dynamic Facility Layout Problem (DFLP) considered in this paper minimizes the total material handling and re-arrangement cost. In this study, an integrated DFLP model with unequal facility areas, assignment of material handling devices (MHD), and flexible bay structure (FBS) is considered, and it is aimed to propose fast solution approaches. Two different solution methods are proposed for the problem, which are the genetic algorithm and the simulated annealing algorithm, respectively. In both methods, a non-linear mathematical model solution was used to calculate the fitness values. Thus, the solutions in the feasible solution space are utilized. The proposed solution approaches were applied to solve four problems published in the literature. The computational experiments have validated the effectiveness of the algorithms and the quality of solutions produced.

Redesign The Layout of Production Facilities at a Garment Company Using the BLOCPLAN Method to Optimize Material Handling

Facility layout design is crucial in production layout setups. The composition of facilities that corresponds to the flow of materials between departments will help to ensure the production system's continuity. PT. KMC is a garment company in West Jakarta that manufactures shirts, dresses, and t-shirt bloats. The company's current layout facilities have not run optimally. This is because inefficient movement distances result in wasted material handling costs, and crossing production flows between departments cause production processes to be disturbed. The objective of this project is to rethink facility layouts using the BLOCPLAN approach in order to optimize material handling. The BLOCPLAN approach may examine layout performance and generate new layout ideas for efficient material handling. The discussion is limited because this research was only conducted on one company. Based on the results of the layout redesign using the BLOCPLAN approach, various improvements were obtained, including a 37.12% increase in material handling cost efficiency. The proposed layout with the BLOCPLAN method is able to provide a reduction in material transfer distance of 22.6 meters and a material handling cost of Rp 155,346 when compared to the initial layout, which had a total overall displacement distance of 35.8 meters and an initial layout material handling cost of Rp 247,059, making it much cheaper.

A graph-pair representation and linear programming embedded genetic algorithm for unequal-sized layout of cellular manufacturing systems

PurposeThis paper aims to deal with intra and inter-cell layout problems in cellular manufacturing systems. The model is organized to minimize the total handling cost, i.e. intra and inter-cell handling costs in a continuous environment.Design/methodology/approachThe research was conducted by developing a mixed integer mathematical model. Due to the complexity and NP-hard nature of the cellular manufacturing layout problem, which mostly originated from binary variables, a “graph-pair” representation is used for every machine set and cells each of which manipulates the relative locations of the machines and cells both in left-right and below-up direction. This approach results in a linear model as the binary variables are eliminated and the relative locations of the machines and cells are determined. Moreover, a genetic algorithm as an efficient meta-heuristic algorithm is embedded in the resulting linear programming model after graph-pair construction.FindingsVarious numerical examples in both small and large sizes are implemented to verify the efficiency of the linear programming embedded genetic algorithm.Originality/valueConsidering the machine and cell layout problem simultaneously within the shop floor under a static environment enabled managers to use this concept to develop the models with high efficiency.

Potassium hexafluorotitanate as a catalytic activator for direct amidation of carboxylic acids

Described herein is the direct amidation of a range of carboxylic acids, in moderate to excellent yields, using potassium hexafluorotitanate (K2TiF6) as a catalytic activator. The ready commercial availability, low cost, and ease of handling of the catalyst, as well as the simple, chromatography-free work-up of the reaction renders the process very appealing.

A Sustainable Strategy for Marker-Assisted Selection (MAS) Applied in Grapevine (Vitis spp.) Breeding for Resistance to Downy (Plasmopara Viticola) and Powdery (Erysiphe Necator) Mildews.

Plant breeders utilize marker-assisted selection (MAS) to identify favorable or unfavorable alleles in seedlings early. In this task, they need methods that provide maximum information with minimal input of time and economic resources. Grape breeding aimed at producing cultivars resistant to pathogens employs several resistance loci (Rpv, Ren, and Run) that are ideal for implementing MAS. In this work, a sustainable MAS protocol was developed based on non-purified DNA (crude), multiplex PCR of SSR markers, and capillary electrophoresis, and its application on grapevine seedlings to follow some main resistance loci was described. The optimized protocol was utilized on 8440 samples and showed high efficiency, reasonable throughput (2-3.2 min sample), easy handling, flexibility, and tolerable costs (reduced by at least 3.5 times compared to a standard protocol). The Rpv, Ren, and Run allelic data analysis did not show limitations to loci combination and pyramiding, but segregation distortions were frequent and displayed both low (undesired) and high rates of inheritance. The protocol and results presented are useful tools for grape breeders and beyond, and they can address sustainable changes in MAS. Several progenies generated have valuable pyramided resistance and will be the subject of new studies and implementation in the breeding program.

DESIGN OF STORAGE LAYOUT FOR PROTECTOR MATERIAL (FAST MOVING) WITH CLASS BASED STORAGE METHOD AT RAW MATERIAL WAREHOUSE JEPARA PT DSV SOLUTIONS INDONESIA (SEMARANG BRANCH)

PT DSV Solutions Indonesia Semarang Branch is a 3PL company engaged in warehousing logistics. The current condition is that the protector material storage still uses a randomized storage method and the GR (Good Receiving) method which rearranges the boxes into pallets. The current layout causes a fairly high displacement distance and has an impact on high material handling costs and the size of the blocks on the shelves that make the GR method long. The purpose of this study is to design a storage layout for protector (fast moving) materials using the class-based storage method to determine changes in displacement distance, material handling costs, and work efficiency and performing the GR (Good Receiving) process. Researchers used descriptive qualitative research methods with observation, interviews, and documentation. The results showed the total distance of the initial displacement of the protector material was 16,172,250 m and the Material Handling Cost was Rp 109,971,300 and the GR process did not require rearrangement into pallets. The output of this research is that it can reduce the total distance of moving the protector material and streamline the distance of movement by 56% and streamline the Material Handling Cost by 56%. In the changed GR (Good receiving) method, it can raise the beam on the level 3 shelf, by 1.5m. The material protector storage layout can be said to be efficient using the class-based storage method when compared to the initial storage layout.

P-806 Heritable genome editing in haploid mouse embryonic stem cells

Abstract Study question Can we edit a specific gene by CRISPR-Cas9 in haploid mouse embryonic stem cells? Summary answer We successfully carried out heritable genome editing of a coat pigmentation gene in haploid mouse embryonic stem cells via electroporation. What is known already Embryonic stem cells have been widely used as a substrate to carry out genetic studies due to their availability, low cost and ease of handling. CRISPR-Cas9 has been successful in editing genes in the human model. Gene editing occurred by homology directed repair or non-homologous end joining. The utilization of a haploid genome would confirm the feasibility of non-homologous end joining repair mechanism. Study design, size, duration In the past 3 months, diploid as positive control and experimental haploid embryonic stem cells were independently cultured for genome editing experiments. Electroporation was used as a means to introduce CRISPR-Cas9 into cells. The negative control cohort consisted of embryonic stem cells electroporated without delivering any CRISPR solution. CRISPR-Cas9 was designed to knock out the Tyr gene to create an albino phenotype. Participants/materials, setting, methods Diploid embryonic stem cells were derived from C57BL/6 mice. The haploid counterpart instead was obtained from haploid androgenetic embryos using spermatozoa from Oct4-EGFP mice. CRISPR solution was prepared by combining Tyr gRNA and Cas9 protein. For each experiment, one million cells were suspended in CRISPR solution and an electroporation buffer. Then, electric pulses were applied for electroporation with 4 different parameters. Gene modification at the target site was confirmed using T7E1 cleavage assay. Main results and the role of chance A 584 base pairs region around the CRISPR target site was amplified in all the diploid and haploid mouse embryonic stem cells. After performing T7E1 cleavage assay, editing efficiency was calculated following the manufacturer protocol. Precisely, after testing out different electroporation conditions on diploid mESCs, 1350V/20ms/2 pulses together with the combination of three sgRNAs (exon 1 and exon 2) and Cas9 protein, provided the best genome editing efficiency at 36.8% with a viability of 80%. Interestingly, when delivering only one type of gRNA (exon 2) together with Cas9 protein, we saw an efficiency rising to 77.6%. We then used the same condition to edit the Tyr gene in the genome of haploid androgenetic stem cells and confirmed that also in these cells, we were able to obtain a comparable genome editing efficiency at 68.4%. Limitations, reasons for caution While these experimental observations are limited, it is encouraging that it is possible to target and edit a haploid genome with a single allele. Wider implications of the findings The utilization of a haploid cell culture model paves the way to utilize CRISPR-Cas9 for gamete genome editing. This will provide a consistent and reliable method to correct inheritable genetic conditions on gametes allowing uniform gene editing of all cell progeny. Trial registration number Not applicable

Simulation-Based Assessment of Hyperconnected Megacity Parcel Logistics

Background: The concept of Hyperconnected Megacity Parcel Logistics (HMPL) was introduced in 2018 and aims to enhance the efficiency, responsiveness, resilience, and sustainability of parcel movements in megacities. However, evaluating such fundamental solutions presents challenges and requires a comprehensive understanding of all stakeholders and decisions involved. Methods: This study introduces a discrete-event agent-based simulation platform that encompasses critical stakeholders and addresses various levels of decision-making. This platform provides an opportunity to evaluate key decisions within an HMPL structure. Results: To demonstrate the capability of the simulator, we assess the impact of package routing and consolidation strategies facilitated by HMPL compared to traditional practices. Preliminary findings suggest that increased interconnection among nodes in HMPL reduces transit times, thereby enabling tighter customer delivery services. However, examining different consolidation heuristics reveals potential trade-offs between handling and shipping costs under fixed shipment schedules, prompting further investigation into dynamic shipment services. Conclusions: The findings of this study suggest that the benefits of innovative approaches in a complex environment, such as parcel logistics, cannot be evaluated in isolation from other decisions. Accurate assessment of the ultimate outcomes and underlying trade-offs requires multi-faceted models that incorporate all key variables.

A hierarchical solution framework for dynamic and conflict-free AGV scheduling in an automated container terminal

Container terminals worldwide are experiencing their transitions into automated and intelligent terminals in the face of the ever increasing container handling demand and cost pressure. A key to cost-effective operations in automated container terminals is the efficient AGV scheduling algorithm that enables on-time fulfillment of container loading and discharging tasks. In this paper, we study an integrated task assignment and path planning problem for AGV scheduling in an automated container terminal. We propose a hierarchical solution framework to empower dynamic AGV scheduling, where the higher level employs a reinforcement learning algorithm for dynamic task assignment and the lower level makes use of a tailored path generation algorithm to generate low-cost and conflict-free paths for AGVs to serve the tasks. Additionally, we propose a container matching heuristic and a two-layer grid map to enhance the learning ability of the reinforcement learning algorithm. We compare the performance of the hierarchical solution framework against various benchmark methods on problem instances of practical scales. The results show that our approach is effective in reducing task delays and mitigating path conflicts, making the task assignment and path planning decisions more applicable for AGV scheduling in an automated container terminal.

Unlocking zinc storage in silver vanadate structures for high-performance aqueous zinc batteries

Zinc-ion batteries (ZIBs) are being increasingly recognized as promising candidates for large-scale energy-storage systems owing to their stability in air, abundance of elemental zinc, low cost, and ease of handling. Although various cathode materials have been explored for ZIBs, silver vanadate stands out for its highly stable structure. However, the presence of silver in silver vanadate may hinder its electrochemical performance, necessitating activation over several cycles. In this study, we introduce an ion-exchange reaction to directly activate silver vanadate. The resulting ion-exchanged zinc vanadate demonstrates superior performance compared with silver vanadate, showcasing stable cycling behavior and high-rate capability. Remarkably, it maintains a capacity retention of 71 % even after 400 cycles. Analysis of the zinc intercalation mechanism reveals a combination of capacitive and diffusion-based processes contributing to energy storage in ZIBs. Post-cycling examinations reveal the presence of dendritic zinc anodes and confirm the stability and safety of the framework, with no silver migration to the anode side. These findings highlight the potential of ZIBs as next-generation energy-storage solutions and underscore the need for continued research in optimizing electrode materials and electrolytes for practical applications.

Intermodal Transportation Challenges in Eastern Europe: Case Study of Romania

Abstract The purpose of this paper is to analyze data from the Romanian intermodal transportation sector and provide an overview of its main terminals (sea, river, road and rail) and the operational challenges faced by its most important logistics service providers. Intermodal transportation (by rail) is encouraged at EU level as a sustainable alternative to current predominant truck haulage. Most research articles outline issues with connectivity, terminal handling infrastructure and cost efficiency as factors hindering large scale adoption. Other authors tend to emphasize the more reliable delivery schedules, reduced road congestion and emissions as drivers of cost competitiveness on medium term. Relevant cargo volume traffic (tons, TEU and ITU) is analyzed at Romania’s main intermodal hubs in the last 10 years (2014-2023) using quantitative and qualitative data to provide a comprehensive overview of its overall competitiveness in this sector. Most Eastern European countries are faced with the same challenge in terms of intermodal transportation: the shortcomings of their supporting network due to insufficient public investment, highlighted by the results from Romania (case study method). Main results show Constanta Port had record cargo traffic in 2023, but its throughput is hindered by constant congestion issues, similar to the highly competitive road sector where intense truck traffic creates bottlenecks on the major roads leading to Western Europe. Cargo is also shipped via the Danube and freight trains, but to a limited extent due to low average speeds and inconsistent reliability along most sectors. The paper highlights the importance of a country’s strategic hubs and their connectivity (sea and/or river ports, main railway lines and road sectors) as a source of future growth and development perspectives, for terminal operators as well as neighboring regions (EU and EEA) through increased business activity.

Involvement of Private Pharmacies in the Biological Diagnosis of Malaria Cases: The Case of Côte d’Ivoire

Introduction. In Côte d’Ivoire, current policy recommends the introduction of rapid diagnostic tests (RDTs) for malaria, including in the private sector, to facilitate effective case management. The main objective of the study was to examine the impact of introducing RDTs in private pharmacies with regard to national recommendations. Patients and methods. In order to assess knowledge, attitudes and practices after a few years of practice, a cross-sectional study was carried out from August to December 2015 among 300 professionals from private pharmacies (PPs) in the northern zone of the city of Abidjan. Results. Overall, PPs performing RDTs accounted for 25.1%. Fever (63.3%), headache (17.7%) and body aches (16.1%) were the main signs that led pharmacists to perform the test. The main criteria determining the choice of RDT are good sensitivity and specificity (45.6%), easy handling (42.6%) and lowest cost (11.8%). In 57.4% of cases, pharmacists performing RDTs said that the cost of the test (CFA 2000 or EUR 3 on average) is the main reason for non-acceptance by customers. In 97.1% of cases, the measures taken in the event of negative results were symptomatic treatment counselling followed by a medical consultation. In 2.9% of cases, some pharmacists recommended an antimalarial. On the other hand, in 92.6% of cases, the measures taken in the event of a positive result were antimalarial treatment with artemisinin-based combination therapies (ACTs). For pharmacies that did not carry out RDTs (74.9%), low customer demand was cited in 56.1% of cases. Conclusion. It would be appropriate for private pharmacy outlets to comply with the legislation by not carrying out RDTs within their pharmacies. Pending the implementation of these texts, it is imperative to improve on the shortcomings revealed.