Production Scheme Research Articles

Production planning with flexible manufacturing systems under demand uncertainty

This paper delves into the impacts of an ongoing global crisis on the resilience of supply chains. Furthermore, it proposes measures to address and mitigate the disruptions caused by the prevailing uncertainties. For example, while the economy has started to recover after the pandemic and demand has increased, companies have not fully returned to their pre-pandemic levels. To enhance their supply chain resilience and effectively manage disruptions, one viable strategy is the implementation of flexible/hybrid manufacturing systems. This research is motivated by the specific requirements of Vestel Electronics, a household appliances company, which seeks a flexible/hybrid manufacturing production setup involving dedicated machinery to meet regular demand and the utilisation of flexible manufacturing system (FMS) to handle surges in demand. We employ a scenario-based approach to model demand uncertainty, enabling the company to make immediate and adaptive decisions that take advantage of the cost-effectiveness of standard production and the responsiveness of FMS. To solve the problem, we propose a heuristic algorithm based on column generation. The numerical results demonstrate that our optimisation model provides solutions with an average optimality gap of less than 6% while also reducing the average cost of standard production schemes without FMS by over 12%.

Specificity Testing for NGT PCR-Based Detection Methods in the Context of the EU GMO Regulations.

The term new genomic techniques (NGTs) is an umbrella term used to describe a variety of techniques that can alter the genetic material of an organism and that have emerged or have been developed since 2001, when the existing genetically modified organism (GMO) legislation was adopted. The analytical framework used to detect GMOs in Europe is an established single harmonized procedure that is mandatory for the authorization of GM food and feed, thus generating a reliable, transparent, and effective labeling scheme for GMO products. However, NGT products can challenge the implementation and enforcement of the current regulatory system in the EU, relating in particular to the detection of NGT products that contain no foreign genetic material. Consequently, the current detection methods might fail to meet the minimum performance requirements. Although existing detection methods may be able to detect and quantify even small alterations in the genome, this does not necessarily confirm the distinction between products resulting from NGTs subject to the GMO legislation and other products. Therefore, this study provides a stepwise approach for the in silico prediction of PCR systems' specificity by testing a bioinformatics pipeline for amplicon and primer set searches in current genomic databases. In addition, it also empirically tested the PCR system evaluated during the in silico analysis. Two mutant genotypes produced by CRISPR-Cas9 in Arabidopsis thaliana were used as a case study. Overall, our results demonstrate that the single PCR system developed for identifying a nucleotide insertion in the grf1-3 genotype has multiple matches in the databases, which do not enable the discrimination of this mutated event. Empirical assays further support this demonstration. In contrast, the second mutated genotype, grf8-61, which contains a -3 bp deletion, did not yield any matches in the sequence variant database. However, the primer sequences were not efficient during the empirical assay. Our approach represents a first step in decision making for analytical methods for NGT detection, identification, and quantification in light of the European labeling regulations.

Construction of acceptance sampling schemes for exponential lifetime products with progressive type II right censoring

Ensuring product quality is crucial for enhancing a company's competitiveness, and product lifetime serves as a vital metric, particularly in the context of electronic goods, for evaluating product quality. To meet quality requirements and mitigate risks for both producers and consumers, thorough examinations of components and final products are necessary. Acceptance sampling plans are commonly employed to achieve these objectives. When assessing product lifetime under non-normal distributions, the lifetime performance index emerges as a valuable and frequently utilized metric. In practical scenarios, lifetime tests may encounter challenges such as the absence of experimenters to observe all product lifetimes and the possibility of accidental product breakage. To address these issues, this study introduces two sampling schemes: a single sampling plan and a repetitive group sampling plan. These plans are specifically designed for exponential lifetime products, utilizing the progressively type II right censored sample as the data type for lifetime testing. The study provides tabulated plan parameters for practical implementation and presents a comparative analysis between the two proposed plans. Furthermore, a practical example is presented to demonstrate the efficacy of the developed sampling plans.

A New Event‐Based Error Decomposition Scheme for Satellite Precipitation Products

AbstractUnderstanding the nature and origin of errors in satellite precipitation products is important for applications and product improvement. Here we propose a new error decomposition scheme incorporating precipitation event (continuous rainy periods) information to characterize satellite errors. Under this framework, the errors are attributed to the inaccuracies in event occurrence, timing (event start/end time), and intensity. The Integrated MultisatellitE Retrieval for Global Precipitation Measurement (IMERG) is used as our test product to apply the method over CONUS. The above‐listed factors contribute approximately 30%, 20%, and 50% to the total bias, respectively. Significant asymmetry exists in the temporal distribution of biases throughout events: early event endings cause threefold more precipitation amount bias than late event beginnings, while early event beginnings cause fourfold more bias than late event endings. Dominant contributors vary across seasons and regions. The proposed error decomposition provides insight into sources of error for improved retrievals.

Techno-economic analysis of a hybrid renewable energy system integrated with productive activities in an underdeveloped rural region of eastern Indonesia

Abstract The Southwest Maluku region in eastern Indonesia is considered a frontier, outermost and underdeveloped region. Its inhabitants live on isolated islands, including the residents of Mahaleta Village, where only 9.4% of the community have limited access to electricity. This study aimed to design an economically feasible hybrid renewable energy (RE) system based on solar and wind energy to integrate with the productive activities of the village. The study developed conceptual schemes to meet the demand for electricity from the residential, community, commercial and productive sectors of the village. The analysis was performed using a techno-economic approach. The hybrid system was designed using the HOMER Pro optimization function, and cold-storage and dryer systems were designed to support related productive activities. The optimized design of the hybrid RE system comprised 271.62 kW of solar photovoltaics, 80 kW of wind turbines and a 1-MWh lead–acid battery. We found that the hybrid RE system would only be economically feasible with a full-grant incentive and an electricity tariff of $0.0808/kWh. However, the productive activity schemes were all economically feasible, with a cold-storage cost of $0.035/kg and a drying cost of $0.082/kg. Integrating the hybrid RE system with productive activities can improve the economic feasibility of the energy system and create more jobs as well as increase income for the local community.

Study of hydrogen production from coal gasification in supercritical water

The coal supercritical water gasification technology is a new technology that directly converts coal into hydrogen, with advantages such as cleanliness, high efficiency, and low cost. With the global trend towards hydrogen energy development, the coal supercritical water gasification technology has broad application prospects. Research on this technology is significant for providing a new path for China's clean energy development, promoting sustainable development in the energy field, and contributing to global emission reduction and climate change response. This article analyzes the current development status of coal gasification technology, summarizes the related categories in four aspects: raw material selection, catalysts, reactors, and heating methods, and analyzes the unique advantages of each method. Based on this, a relatively efficient hydrogen production scheme is briefly selected. In addition, the future development trend of this technology is discussed. This article may provide a reference for clean energy development and the efficient utilization of coal resources.

Cost estimation and performance evaluation of 3D printed membranes for vanadium redox flow batteries

AbstractThe membrane is a central component in the commercialization of vanadium redox flow batteries (VRFB), with Nafion being the preferred material for those membranes. Nafion suffers however from high vanadium crossover and high cost, thus limiting its wider commercial application in VRFB. To address this, studies have focused on sulfonated polyether ether ketone (SPEEK) as an alternative material. This work presents an economic study on the production costs of 3D printed SPEEK (3D‐SPEEK) membranes for VRFB, with multiple production scenarios evaluated. This analysis relies on the performances of 3D‐SPEEK membranes prepared in our laboratory, which have shown higher Coulombic efficiency and lower vanadium ions diffusion than Nafion membranes. Results from the economic analysis revealed that the cost of the 3D‐SPEEK membrane varies from 567.77 to 79.35 €/m2 depending on the production scheme and scale used. Production costs lower than commercial Nafion membranes are achieved when a large production scheme is used. Further analysis shows that 3D‐SPEEK membranes might even be cheaper than conventional SPEEK membranes if their printing time is reduced.

Methodological proposal for the standardization of the Electronic Navigational Chart scheme in the Caribbean Sea

Since the approval of the use of Electronic Navigational Charts (ENC) as equivalent to paper nautical charts, hydrographic services worldwide began their production following existing cartographic schemes. This paper proposes to standardize ENC production schemes at the regional scale through a regular grid system, which unifies the scale of compilation and cell size by navigational purpose. The implementation of this system requires defining the origin of the grid and facilitates the nomenclature of the ENCs. Additionally, this standardization would help for the harmonized production of ENCs by improving their coverage. The proposed methodology is used to formulate an ENCs scheme in the Caribbean Sea, which is part of the Meso American and Caribbean Sea Regional Hydrographic Commission, in order to show its application and advantages. For this region it is proposed to generate a regular grid scheme with cell sizes and compilation scales (1:K) for Overview, General and Coastal navigational purposes of 24° × 24°, 6° × 6° and 1.5° × 1.5° and 1:3,000, 1:700 and 1:180 respectively, which allows to eliminate irregularities between the ENCs. This proposal contributes to the safety of maritime activities, seeking to enhance the quality of the ENC products in this region and increase trust to Electronic Chart Display and Information System users through enhanced visualization and seamless transition between ENCs of the same compilation scale. Additional serves as input for the modernization of the ENC schemes in the different Regional Hydrographic Commissions of the International Hydrographic Organization.

Development of an algorithm for the reasoned selection of machines for leather garments manufacturing

The technology of processing clothing elements is very mobile and changes with the appearance of new materials and equipment. The selected design and technological solutions that ensure the conformity of aesthetic properties and requirements can be satisfied through continuous improvement of sewing production technologies. This study aims to develop an algorithm for choosing the optimal equipment, taking into account the material parameters and the permissible requirements for the technological process of manufacturing sewing products from artificial leather. As a result of the analysis of the range of sewing machines and manufacturing companies, Juki sewing machines were chosen to build a complex matrix of machine equipment. A morphological scheme of the selection process and a mathematical description of the two-dimensional matrix of elements have been developed. That has made it possible to reflect the simultaneous consideration of all process components and their influence on the technological parameters of the machine. The database of the parameters of the equipment selection system was built in the form of matrix elements: a matrix of the type of operations, a matrix of material coatings, a matrix of the base of materials, a matrix of machine assignments, and a matrix of qualifications. Each matrix is a production rule for making a decision at a separate selection stage. The operation matrix was constructed using the TechLab mobile application, which includes 50 processing schemes for artificial leather products. The analysis of the schemes has made it possible to determine the frequency of occurrence of types of seams for processing artificial leather products: 1.01.01 (28.75 %), 2.01.01 (16.75 %), 1.06.02 (11.00 %), 2.02.01 (15.50 %), 5.01.01 (24.25 %), 6.02.01 (3.75 %). The mathematical notation of the algorithm for choosing the optimal machine equipment has made it possible to visualize the structure of the process using a graph. The graph was built using Gephi. Such a notation takes into account the qualification of the worker, the type of technological operation, and the material’s properties, including the material’s thickness, coating, and base.

A New Approach for Production Prediction in Onshore and Offshore Tight Oil Reservoir

Rapid technological advances have accelerated offshore and onshore tight oil extraction to meet growing energy demand. Reliable tools to carry out production prediction are essential for development of unconventional reservoirs. The existed tri-linear analytical solutions are verified to be versatile enough to capture fundamental flow mechanisms and make accurate production predictions. However, these solutions are obtained in Laplace space with the Laplace transform and numerical inversion, which may lead to uncertainty in the solution. In this paper, a general analytical solution is derived in real-time space through integral transform and average pressure substitution. Namely, the partial differential equations describing subsurface fluid flow are firstly triple-integrated and then the obtained volume average pressure are replaced with the rate-dependent expressions. Furthermore, the ordinary differential equations related to oil rate are solved analytically in real-time space. To validate our model, this derived solution is verified against two numerical models constructed with two typical physical configurations. The great match indicates the accuracy and applicability of the analytical solution. According to the developed workflow, two field cases including offshore and onshore tight oilfield data are selected for history matching and production prediction. This new approach not only makes the obtained solution more simplified, but also helps field engineers diagnose flow patterns more quickly to better optimize production schemes.

Challenges and opportunities of using Bos indicus cattle to meet consumers' demand for quality beef

Beef consumption is expected to increase worldwide, which necessitates the use of Bos indicus cattle that are well-adapted to harsher climates, like the tropics. Yet, beef from these cattle is considered inferior to that of Bos taurus breeds, primarily due to lowered tenderness values and reduced intramuscular fat content. However, the benefits of using Bos indicus genetics are numerous and undeniable. Herein, we explore how decreases in meat quality in these cattle may be offset by increases in livability. Further, we review the knowledge surrounding beef tenderness and explore the processes occurring during the early events of the transformation of muscle to meat that are different in this biological type and may be altered by stress. Growth rate, calpastatin activity and mitochondrial function will be discussed as they relate to tenderness. The opportunities of using Bos indicus cattle are of great interest to the beef industry worldwide, especially given the pressures for enhancing the overall sustainability and carbon footprint of this sector. Delivering a consistently high-quality product for consumers by exploiting Bos indicus genetics in a more sustainable manner will be proposed. Information on novel factors that influence the conversion of muscle to meat is explored to provide insights into opportunities for maximizing beef tenderization and maturation across all cattle. Exploring the use of Bos indicus cattle in modern production schemes, while addressing the mechanisms undergirding meat tenderness should provide the industry with a path forward for building greater demand through producing higher quality beef.

On the Terwilliger algebra of the group association scheme of Cn⋊C2

In 1992, Terwilliger introduced the notion of the Terwilliger algebra in order to study association schemes. The Terwilliger algebra of an association scheme A is the subalgebra of the complex matrix algebra, generated by the Bose-Mesner algebra of A and its dual idempotents with respect to a point x.In Bannai and Munemasa (1995) [3] determined the dimension of the Terwilliger algebra of abelian groups and dihedral groups, by showing that they are triply transitive (i.e., triply regular and dually triply regular). In this paper, we give a generalization of their results to the group association scheme of semidirect products of the form Cn⋊C2, where Cm is a cyclic group of order m≥2. Moreover, we will give the complete characterization of the Wedderburn components of the Terwilliger algebra of these groups.

Microbial ecology and metabolite dynamics of backslopped triticale sourdough productions and the impact of scale

Triticale (X Triticosecale Wittmack) is a hybrid of wheat (Triticum aestivum L.) and rye (Secale cereale L.), combining the positive attributes of both cereals. However, it has not been exploited for sourdough production yet. Further, the effect of scale on sourdough production has not been investigated systematically up to now. The aims of the present study were to assess the microbial ecology and metabolomic output of eleven spontaneously fermented, backslopped sourdough productions made with triticale flour on a scale of 100, 200, 500, and 1000 g. The acidification profile [pH and total titratable acidity (TTA)], microbial diversity (culture-dependent and culture-independent), metabolite dynamics, and appropriate correlations were determined. After ten fermentation steps, different species of Lactobacillaceae were prevalent in the mature sourdoughs, in particular Latilactobacillus curvatus, Limosilactobacillus fermentum, and Pediococcus pentosaceus. The microbial diversity could be traced back to the grains and was also present in the milling fractions (flour, bran, and shorts). Furthermore, thanks to the use of Illumina-based high-throughput sequencing and an amplicon sequence variant (ASV) approach, the presence of undesirable bacterial groups (bacilli, clostridia, and enterobacteria) during the initial steps of the backslopping cycle was revealed, as well as a finetuned taxonomic diversity of the LAB genera involved. Small sourdough productions (100 and 200 g) selected for a lower species diversity and reached a stable consortium faster than large ones (500 and 1000 g). Although a comparable final pH of 3.6–4.0 was obtained, the TTA of small sourdoughs was lower than that of large ones. Regarding the metabolic output, the simultaneous production of mannitol and erythritol, beyond ethanol and glycerol, could be linked to sourdoughs in which Liml. fermentum was the sole LAB species present. Further, the use of the arginine deiminase pathway by P. pentosaceus and Liml. fermentum was obvious. An appropriate extraction method followed by liquid injection gas chromatography coupled to triple quadrupole tandem mass spectrometry allowed the quantification of interesting volatile organic compounds, such as ethyl lactate. These findings support the inclusion of triticale as a viable alternative to wheat or rye for the production of sourdoughs that can be integrated into bread-making production schemes.

H2 production through natural gas reforming and carbon capture: A techno-economic and life cycle analysis comparison

As policy incentivizes low-carbon hydrogen production, there is growing interest in the deployment of natural gas hydrogen production with carbon capture and storage (CCS). Here, we conduct comprehensive techno-economic analysis (TEA) and life cycle analysis (LCA) on five hydrogen production cases, with a focus on characterizing emissions and cost implications of varying CCS schemes for hydrogen production with CCS. We find that CCS cases can achieve over 95% CO2 capture at the plant, while reducing the well-to-gate (WTG) greenhouse gas (GHG) emissions to 3.21–3.65 kg CO2 eq/kg H2, this is 63–68% lower than the emissions of industrial baseline case. The levelized cost of hydrogen (LCOH) of CCS pathways is estimated in the U.S. context to be 1.17–1.56 $/kg as compared to $1.04/kg of industrial baseline case. Given regional variations in fuel and electricity prices and their upstream emissions impacts, we also performed a regional analysis of the proposed pathways.

Adaptive Type-II Hybrid Progressive Censoring Samples for Statistical Inference of Comparative Inverse Weibull Distributions

Recently, there has been a lot of interest in comparative life testing for items under jointly censored schemes for products from multiple production lines. The inverse Weibull distribution (IWD) is commonly used in life testing and reliability theory. In this paper, we address the problem of statistical inference from comparative inverse Weibull distributions under joint samples. An adaptive type-II hybrid progressive censoring scheme (HPCS) is used to save the balance between the ideal test time and the number of observed failures. Under the adaptive type-II HPCS, unknown parameters of the inverse Weibull populations are estimated using both maximum likelihood and Bayesian approaches. Asymptotic confidence intervals are established using the observed Fisher information matrix and bootstrap confidence intervals. We suggest using Markov chain Monte Carlo (MCMC) techniques to compute credible intervals under independent gamma priors. Using Monte Carlo simulations, all theoretical conclusions are tested and contrasted. For illustration purposes, an actual sample from comparative populations is analysed.

Analisis Perilaku Moral Hazard dan Adverse Selection pada Agency Problem di Pembiayaan Musyarakah PT. Bank Sumut KCPSY Binjai

This study aims to determine the form of behavior and how to handle agency problems caused by moral hazard behavior and adverse selection in musyarakah financing at PT. Bank Sumut KCPSY Binjai. The agency problem is the agency problem in the musyarakah product scheme. This type of research is field research with qualitative methods. Sources of data in this study include two categories, namely primary data and secondary data. The subjects in this study were employees of PT. Bank Sumut KCPSY Binjai in the management section that is competent in the field of musyarakah financing. The research results show that the form of moral hazard and adverse selection behavior at PT. Bank Sumut KCPSY Binjai namely the difficulty of banks assessing the true character of customers, errors in analysis, ethical deviations and lack of supervision (monitoring) carried out by banks. PT. Bank Sumut KCPSY Binjai Office made various efforts from screening, verification to monitoring. Furthermore, if the problem of moral hazard and adverse selection has occurred, the bank will handle it in two ways, namely saving financing in the form of first rescheduling, reconditioning, restructuring and solving problem financing by means of billing. lawsuits, execution of mortgage auctions, and WO

Imaginaries of ECEC: A comparison of policies of access in early childhood education in Brazil, Finland, Hungary, Indonesia, Iran, Nepal, and Serbia

Increasing access to ECEC has been on the agendas of international organizations and many countries in different parts of the world. Despite the clear global interconnectivity, this article shows that contextual factors are essential to understand educational policy developments. The study examines reforms related to policies of access to ECEC in seven countries. Brazil, Finland, Hungary, Indonesia, Iran, Nepal, and Serbia. We show how access policies plug into the understanding of the role of ECEC as producing future citizens. Even though the main idea of ECEC’s role in developing future citizens is present in each national context, it takes different forms: the roles frame access policies as a way to strengthen either human capital via focusing on learning and skill formation, and/or the national identity of future citizens. They materialize in differing ways, for example, as coercive legislative requirements, fee policies, and knowledge production schemes. In addition, national access policies adopt different relations to the policies of international organizations, reflecting the socio-political context of the country. We argue that the concept of the imaginary is useful in allowing us to examine the interplay between the semiotic and non-semiotic aspects of policy. To further unravel the complexity inherent in such policies in terms of their local diversity, we suggest the usefulness of case studies and the examination of local-level policies in their full variety instead of only national ones, as these might be fruitful avenues for future research.

Clean and sustainable power/fresh water/hot air production scheme based on solid oxide fuel cell feed by apricot stone biomass: A multi-attribute optimization

Developing novel and low-emission multi-generation systems is attracting considerable critical attention. In this regard, a novel tri-generation of power, fresh water and hot air has been developed in this study based on solid oxide fuel cell. Power has been generated by a solid oxide fuel cell, a gas turbine cycle and a super-critical carbon dioxide Brayton cycle. An air flow has been heated in a heat exchanger and fresh water has been produced through a desalination unit. Super-critical carbon dioxide Brayton cycle, heat exchanger of hot air and desalination unit have been all triggered by a co-combusted gas of apricot stone and synthesis gases of solid oxide fuel cell. Analysis of variance has been utilized to identify the significant influences on power production, fresh water, hot air, emission effect of system and system efficiency. Multi-objective optimization has showed that apricot stone of 200 kg/h, fuel utilization of 0.77, current density of 9697 A/m2 and pressure ratio of 3 in gas turbine system are the optimum conditions. The system has produced 2.10 MW of power, 837 g/h of fresh water and 57 m3/h of hot air with an emission effect of 2069 kg/MW.h and an efficiency of 43.5%.

A comparative study of the reaction mechanism for deep reduction hydrogen production using two special steel solid wastes and a chemical looping hydrogen production scheme

Pickling sludge (PS) and presintered waste (PW) are two special steel solid wastes that have potential as oxygen carriers due to their Fe content. Using these raw materials to produce hydrogen allows for the resource utilization of solid waste, which has good environmental effects. Here, we studied the deep reduction-hydrogen production characteristics. Specifically, the effects of temperature, papermaking sludge (PMS) blended ratio, and reaction time on the deep reduction characteristics of Fe in pickling sludge and presintered waste were studied. On this basis, the study also aimed to investigate the effects of temperature and PMS blended ratio on hydrogen production. The results indicated that when exposed to high temperature, PMS shows the ability to effectively reduce pickling sludge and presintered waste. The maximum Fe recovery rate can reach 65.63 and 96.94 % in a fixed bed reactor operating at 700 °C and a blended ratio of approximately 10 %. Under the conditions of 900 °C and 15 %/50 % papermaking sludge addition, the Fe content within pickling sludge and presintered waste was reduced to FeCr2O4 and FeO, respectively. Subsequently, during the reaction with steam, Fe2O3 and Fe3O4 were generated in PS and PW, respectively. The hydrogen production per unit mass of Fe2O3 in pickling sludge is higher due to the existence of the FeCr2O4 spinel structure in the reduction product of pickling sludge. According to the above results, two hydrogen production strategies of PS and PW through different deep reduction paths are proposed.

Potential of Rice-Based Food Processing Industries Along Eastern Plains of River Ganga

The Indo-Gangetic plains are considered to be the most fertile land area within India. It contains alluvium type of soil which is rich in nutrients and have high water retention capacity. According to many agricultural think tanks, including Food and Agriculture Organization (FAO), the northern belt of Uttar Pradesh (U.P.) and Bihar are the only states having naturally sustainable soil conditions for the cultivation of water-intensive rice crops in India and are also among very few regions of Asia. This paper will be an attempt to propose an integrated system where Sustainable Development Goals (SDGs) targets like poverty, well-being, economic growth, innovation and infrastructure, and sustainable communities will be addressed. With the optimum production of rice in the region and with the support of government schemes like the Pradhan Mantri Kisan Sampda Yojana scheme for overall growth and development of food processing units, food processing industries can be established in selected pockets of eastern Uttar Pradesh and Bihar. The food processing industries based on rice processing will produce varied local sweets such as Anarsa, Lakhtho, Thekua, etc., and food products that can get a vital push from the government’s One District One Product (ODOP) scheme. With the help of the Agricultural and Processed Food Products Export Development Authority (APEDA), the products can be promoted for international exports as well. Also, it will address the much-known menace of outmigration (4–5 million of workforce per annum) from states and will provide local human capital with income growth and identity. A whole integrated system can be built where linkages from farm to market can be created which will reap farmers: good prices and regular procurement, food industries: good promotion of products plus profits, and local people: economic and social protection. Therefore, by using locally climate suited crop and government supported food parks or industrial system, the holistic aim of 3P’s – people, planet, and profit, will be realized.