Volume Of Supply Research Articles

Energy-efficient and reliable coordinated scheduling for water distribution systems: enhancing hydraulic conditions and water quality

ABSTRACT Multi-objective operation optimization of water distribution systems (WDSs) in large metropolitan areas is essential; however, it is complex and time-consuming. Effective and reliable scheduling of WDSs can significantly enhance the efficiency and reliability of urban water resources management, which requires further research. This paper develops an optimization method combining genetic algorithm and multiple criteria analysis that coordinates energy conservation, hydraulic condition improvement, and water age optimization in WDSs. Results showed that the optimal scheduling method could achieve a 23.0, 16.7, and 2.5% decrease in energy consumption, and water supply volume with unsatisfied pressure, and average water age, respectively. To achieve optimal results, this study indicated that it is crucial to properly allocate water supply volume and pressure across multiple drinking water treatment plants. This finding provides important guidance for water utilities in scheduling. Furthermore, the emergency scenario analysis shows that the newly proposed method can significantly enhance the social and economic sustainability of WDSs through the coordinated optimization of energy consumption, hydraulic conditions, and water age.

An energy-environment coupled simulation framework for multi-scale and multi-facet evaluation of data center

This paper focuses on analyzing the thermal environment and optimizing energy consumption in data centers, which has largely omitted from previous studies. The thermal environmental of data centers is simulated and analyzed by utilizing the established “server-rack-room” multi-scale heat transfer numerical model. Based on this, the coupling simulation model of thermal environment and energy consumption in data centers is proposed to explore the relationship between them, and the corresponding optimization strategy is put forward. The energy consumption simulated by energy-environment coupled model and non-coupled model can reach a discrepancy of over 30 %, which indicates that the thermal environment impacts the power consumption of the data center significantly. Besides, the effect of several operational parameters of air conditioning system on the thermal environment and energy consumption of data center is analyzed. Through the particle swarm optimization algorithm, the optimal system parameters, which meet the requirements of thermal environment and lead to the lowest energy consumption, are found for typical cities in different climatic regions. The recommended settings include the supply air temperature of about 24 ∼ 26 ℃, the air supply volume of 8 m3/s, and the temperature difference of about 3.5 ℃ between the supply air temperature and the supply chilled water temperature. Under the optimized parameter setting, the highest temperature of server decreases to below 71 ℃, and the energy saving rate is more than 6 %.

Evaluation of water supply function in the Economic Belt of the Northern Slope of the Tianshan Mountains based on the InVEST model

The Economic Belt of the Northern Slope of the Tianshan Mountains (EBNSTM) is a composite ecosystem with mountains, oases, and desert areas; it also serves as an active area for anthropogenic activities. Frequent changes in soil and water resources have significant impacts on regional ecosystems. However, research on the ecosystem water yield function of EBNSTM is relatively limited; additionally, the spatiotemporal variations in the water supply function based on land use changes have not been sufficiently elucidated. This study aimed to explore the land use changes and the spatial variability of water supply service functions in the region at the macro level and uses the land transfer matrix as an important tool to study the changes in land use in the different years of 2000, 2005, 2010, 2015, and 2020. Using the InVEST model, we conducted a quantitative assessment and comprehensive study on the water supply function of EBNSTM across the aforementioned years. Additionally, the study delved into the structure of ecosystem service functions, alongside investigating the spatial and temporal variability of ecosystem services under the multi-scale units of administrative divisions, ecological zones, and land classes. We found that during the 20-year period, the area of construction land of EBNSTM increased by 1089 km2, with the highest dynamic change rate of 4.09 %; 2015–2020 period was the most drastic period of change for each land use type. The average multi-year depth of water production was 87.49 mm, totaling 71.59 × 108 m3. The spatial distribution pattern of the water supply function in the study area during the last 20 years consistently exhibited a distinct pattern: mountainous areas displayed the highest water supply capacity, followed by oases, and deserts ranked the lowest. Further, the water supply service function within the study area is currently experiencing a modest rate of increase. The rate of change in water supply depth was 2.76 mm/a, while the rate of change in water supply volume was 0.47 × 108 m3/a. Areas with enhanced water supply capacity are mostly distributed in the southeast of EBNSTM, whereas the northwest, encompassing the mountainous areas, exhibited a declined water supply capacity. Between 2000 and 2020, the water supply capacity in the study area was ranked as follows: woodland > grassland > unutilized land > cultivated land > urban construction land, with woodland displaying the strongest water supply capacity. When woodlands, grasslands, and croplands were converted to other land use types, their water supply functions generally decreased, and vice versa. Our findings provide a scientific basis for the sustainable management of water and soil resources in EBNSTM.

Quantifying non-target seahorse fisheries and domestic traditional medicine-based trade in Malaysia

Seahorses (Hippocampus spp.) are sold primarily for traditional medicine (TM) uses in Southeast Asia. Although Malaysia is reportedly an important global seahorse exporter, documentation on the current extent of seahorse catch and trade of seahorse-based TM within the country is limited. This study aimed to quantify patterns of seahorse bycatch, gear-specific biological parameters of caught seahorses, and trade characteristics in Malaysia. Questionnaire-based fisher and TM surveys were administered nationwide from March 2021 to March 2023. Seventy-one percent of fisher respondents (612 out of 860) reported catching seahorses, with gill or drift net fishers (73 %) more likely to have caught seahorses than trawlers (12 %). Significant spatial differences in species composition was observed between Peninsular Malaysia and Malaysian Borneo (Sabah state). The total estimated annual seahorse catch within Malaysia was approximately 3376 kg per year, with 77 % of the catch attributed to gill or drift nets and 23 % to trawling operations. Almost half (40 %) of traditional Chinese medicine (TCM) practitioners/ traders (n = 138), 3 % of Malay TM practitioners (n = 3), and 88 % of other TM traders (n = 7) reported selling seahorse species. This study is one of the first to quantify the often overlooked but critical contribution of small-scale fisheries, especially gill and drift nets, towards seahorse bycatch. The current supply volume and selling price of seahorses were observed to be relatively high, while the present-day demand was reportedly low. Almost half of TCM practitioners/ traders interviewed were still actively selling seahorses, indicating that there is still considerable demand. To ensure the sustainability of seahorse populations in Malaysia, efforts in both small-scale and trawl fisheries must be reduced while strictly enforcing seahorse trade regulations.

Analyzing the effects of extreme cold waves on urban water supply network safety: A case study from 2020 to 2021

Urban water supply networks are crucial for the transportation of water resources. However, with the increasing frequency and severity of cold wave disasters linked to climate change, the impact on water supply systems has become a critical concern. These impacts include pipe failures, customer water outages, and challenges in meeting peak winter water demand. To address this, our study analyzes data from cold waves in Shanghai from late 2020 to early 2021. We statistically examined daily water supply volume, pressure, and pipe failures to detect abnormal changes. We also analyzed pipe failure rates based on different characteristics to identify which pipes are most vulnerable to cold wave damage. Understanding the winter cold wave's effects can help water companies prioritize maintenance on aging pipes before such events, reducing damage and improving service. This research adds to the understanding of climate change's impact on urban infrastructure and provides valuable insights for global water companies to optimize their maintenance strategies.

Fluid resuscitation strategy in patients with placenta previa accreta: a retrospective study.

Obstetric hemorrhage is the leading cause of maternal death worldwide. Placenta previa accreta is one of the major direct causes of postpartum hemorrhage, accounting for two-thirds of obstetric hemorrhage cases. Fluid resuscitation is a life-saving procedure for patients suffering from massive hemorrhage. This study aims at evaluating the risk factors of massive hemorrhage and appropriate fluid resuscitation strategy in patients with placenta previa accreta. This study retrospectively analyzed the risk factors for massive hemorrhage, clinical characteristics, and perinatal outcomes of patients with placenta previa accreta. Maternal noninvasively evaluated hemodynamic indicators, including maternal heart rate, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and shock index, were collected and analyzed at nine time points, from the administration of anesthesia until the end of procedures, in patients diagnosed with placenta previa accreta and receiving different fluid supply volumes. Complicated with placenta increta/percreta and gestational age of delivery later than 37 weeks are two independent risk factors of massive hemorrhage in patients with placenta previa accreta. A total of 62.27% (170/273) patients diagnosed with placenta increta/percreta had massive hemorrhage, significantly higher than those diagnosed with placenta previa accreta (5.88%, 6/102). Patients delivered after 37 weeks of gestation had significantly higher ratios (86.84%, 99/114) of massive hemorrhage compared with those delivered between 36 and 36+6 weeks of gestation (35.39%, 63/178). Maternal SBP, DBP, and MAP started to decrease immediately after the baby was delivered and reached a relatively stable trough state at 15-30 min after delivery. No statistical differences were found in hemodynamic indicators, the occurrence of hypotension, or in-hospital days after the procedure among the transfusion volumes < 30 ml/kg, 30-80 ml/kg, and ≥ 80 ml/kg groups. Patients with a suspected diagnosis of placenta previa accreta should plan to deliver before 37 weeks of gestation. The ability to identify concurrent placenta increta/percreta should be improved to schedule a reasonably rapid perioperative plan. Restrictive fluid resuscitation could achieve good effects in maintaining hemodynamic stability in patients with placenta previa accreta. A time period of 15-30 min after delivery is the critical stage for fluid resuscitation.

Modeling the Tourism Market Behavior Based on Discrete Equilibrium Models “Supply – Price – Demand”

Abstract The work is devoted to the modeling of the behavior of the tourism market in the conditions of a supply random lag, distributed according to normal and uniform distribution laws. The behavior of dependences on the tourist market of supply and demand on the price is considered. The modeling of the behavior of the tourism market was carried out using a market dynamic model in the plane of variables “supply – price – demand” taking into account the interests of different groups of consumers, primarily from the point of view of pricing. The delay between changes in supply and demand volumes is taken into account using a Cobweb model. To test this method, information was collected on family expenses when traveling abroad (outbound tourism, tourist vacations lasting 7-15 days) by surveying the employees of 38 travel organizations as of 2021. Three segments of the tourism market are identified: low ($2000 − 4000), medium ($4000 − 12000), and VIP-segment ($12,000 − 20,000). The analysis of the modeling results showed that the behavior of tourists of different segments can significantly influence the market dynamics. The use of a Cobweb model allowed for determining the level of stability of tourist behavior and assessing the possibility of consumer migration from one segment to another. Sensitivity to price changes and response to new offers from different segments can be different, which is important for determining pricing strategies, marketing, and the development of new tourism products.

MODEL OF SPARE PARTS INVENTORY MANAGEMENT IN THE SUPPLY SYSTEM: THE CASE OF THE ‘OLL TRAK PARTS’ COMPANY

The article identifies the relevance of the problem of optimisation of material reserves of a company and their effective management, as the state of existing reserves has a decisive impact on the competitiveness of the company, its financial condition, and the corresponding performance results. It allows the formulation of the research objective in this development. It is a given that inventory management technology is an integral part of the management system of any manufacturing and trading company. The efficiency of these companies depends on such critical criteria as the number of costs incurred for inventory management. Traditional indicators, such as inventory volume, resource turnover, and continuity of supply, cannot be used in isolation to accurately measure the extent to which an inventory management system is improving since they are part of the overall cost criterion. The article examines scientific developments of theoretical foundations for implementing rational solutions in the supply chain, where the authors use modern research methods and approaches. After analysing these studies, we identify the main problematic issues: determining a rational way of servicing orders by the core production warehouse systems, organising an efficient product supply form, and developing rational inventory management technologies throughout the entire product supply chain. We create a structural model of interaction between the warehouse system of the ‘OLL TRAK PARTS’ company and suppliers and customers, formed with the participation of certain parties in all relevant operations. The structure of stocks accounts for the customer’s needs in a multi-nomenclature offer of spare parts for trucks, cars, and agricultural machinery supplied by ‘OLL TRAK PARTS’. The authors build a mathematical model of spare parts inventory management under limited demand conditions, which considers the following parameters of influence: the period for ordering spare parts, the cost of supplying ordered spare parts, and the cost of storing one unit of spare parts inventory. To achieve maximum measurement accuracy with a minimum number of trials and to maintain the statistical reliability of the results, we develop a full-factor experiment plan for three input parameters with three levels of values, consisting of 27 series of trials. The experiment allowed us to model the change in minimum costs with different order volumes of spare parts. Based on the results of the regression analysis of the obtained values of the estimated indicator, we determined the type of regression model – a linear form with a non-zero coefficient. Keywords: model, warehouse, system, logistics, interaction.

Water Lily-Inspired CNT@cotton towel solar evaporator with Marangoni effect and optimal water supply for achieving zero liquid discharge desalination and irrigation

Solar-driven interfacial evaporation is an environmentally friendly technology to address the global water scarcity crisis by efficiently purifying unavailable water resources (seawater, brackish water, high salinity wastewater and various water resources). However, the inevitable contradiction between salt deposition and highly efficient water evaporation during long-term desalination remains a major challenge. In this work, we report a self-floating bionic water lily evaporator with zero liquid discharge, consisting of CNT@cotton towel with the uneven-gap structure as the photothermal material and the square groove insulation foam with controllable water supply as edge-preferred crystallization support. The formed four-building-in ramp structure generates different surface tensions along the whole ramp and brings Marangoni flow. With the combination of Marangoni flow and optimal water supply volume, salt is spatially isolated from the CNT@CT surface, the biomimetic design can achieve continuous water evaporation and salt collection (79 g m-2h−1) for 84 h in 10 wt% NaCl under edge-preferred crystallization. The purified water meets drinking water standards and is applied to growing crops. This distinctive solar evaporator provides new insights for designing a low-cost and zero-liquid-discharge evaporator, advancing its application in high-saline brines, various water resources, and irrigation.

Study on Variation Law of Hazardous Areas in Goaf Based on Coal Oxidation Kinetics Theory

ABSTRACT Regarding various problems on safety production in coal mines, residual coal in goaf’s spontaneous combustion is extensive, determining its hazardous areas is critical to extinguish or prevent fires in goaf. Taking production practices at the 010803-working face of Wang Wa Coal Mine as background, a combined approach involving on-site experiments, laboratory tests, and numerical simulations is adopted to investigate “three-zone” spontaneous combustion as well as the distribution patterns of temperature fields in shallowly buried coal seams. The mathematical and physical models of spontaneous combustion in goaf are constructed. Upon oxidation of coal at low temperatures, experimental data about the intensity of release of heat and the rate of consumption of oxygen inform the construction of a kinetic model for coal oxidation in goaf. Utilizing field-measured data on air leakage, a distribution model for permeability within the working face’s goaf is constructed. To study combustion “three-zone” and temperature field distribution patterns in goaf under various air supply volumes, as well as to quantitatively analyze the relationship between the width and area of oxidation zones, the area of high-temperature areas, and the distribution of high-temperature sites in the goaf, with relation to the working face’s supply volumes of air. The results show that the maximum simulated air leakage in the goaf of the working face is 148.03 m3/min, with a relative error of just 1.4% compared to the measured value. Furthermore, validation confirms that the simulated oxygen concentration variation pattern closely aligns with the measured oxygen concentration. As the airflow rate at the working face increases, the oxidation zone width at the intake side gradually grows. While on the return side, it gradually decreases, resulting in a maximum width difference of 22.6 m. The goaf area’s concentration of oxygen exhibits an “S” shape distribution pattern. The overall temperature change range within the high-temperature zone of the goaf is 4.5 K, gradually migrating toward the deeper areas. As the air supply rate rises, oxidation zone area gradually decreases, exhibiting an overall sinusoidal distribution. Concurrently, the high-temperature zone area progressively expands, conforming to a Boltzmann function distribution. When the Air supply rate is 800 m3/min to 1120 m3/min, the areas of the two are linearly correlated with the air supply volumes. Under varying air supply volumes, the position of the high-temperature point within the goaf changes in both strike and dip directions, and the relative distance with the intake air corner follows an exponential function in both strike and dip directions. Through comprehensive analysis, it is concluded that the actual air supply volume on-site should ideally range between 800 m3/min and 1120 m3/min. This range effectively prevents and controls the hazardous area of spontaneous combustion in the goaf and optimizes the ventilation scheme.

Study on Gas-Liquid Coaxial Jet Foam Generator and Its Foaming Characteristics.

In order to solve the difficulty of the existing compressed air foam system with low FER and difficult in having both the FER and range. A new type of foam generator for CAFS was designed, an air-liquid coaxial foam generator, which produces foam with high FER (the ratio of the foam volume to the volume of the foam solution) and large output momentum. In this paper, experiments on the foam production performance of a gas-liquid coaxial jet foam generator were carried out with different parameters, such as liquid flow rate, gas flow rate, and foam output end diameter. The variation of FER, foam half-life, range, foam volume, and compressed air utilization rate with the experimental parameters were analyzed. The results show that the foaming performance of the foam generator tends to rise in the range of 8-12.4 m3/h at a fixed gas flow rate, the FER and foam half-life are negatively related to it, and the foaming performance tends to decrease in the range of 12.4-18 m3/h. The best foaming performance was achieved when the liquid volume of the foam generator was 12.4 m3/h. For the liquid volume value in different intervals, the foaming performance varies with the air supply volume. When the liquid volume is higher than 12.4 m3/h, increasing the air supply volume is beneficial to improve the foaming performance, and when the liquid volume is lower than 12.4 m3/h, increasing the air volume does not improve the foaming performance. The effect of the diameter of the foaming chamber on the foaming performance is not monotonic, and an optimum value exists. Compared with similar devices, the gas-liquid coaxial jet foam generator has strong advantages in FER and range and has better application prospects for fire control in restricted spaces.

Auctions to reveal consumers’ willingness to pay for low-carbon hydrogen projects: combining lessons from renewables and natural-gas industries

Abstract Low-carbon hydrogen is expected to play a key role in realizing net-zero and sustainable development plans. Nonetheless, there is a gap between the cost of producing low-carbon hydrogen and its potential users’ willingness to pay for such hydrogen. To implement support for the development of the industry, we propose using low-carbon hydrogen long-term agreements allocated through auction mechanisms. The objectives are 2-fold: (i) matching supply and demand volumes considering the time horizon and geographical delivery point specification and (ii) allocating the subsidy. This perspective article innovates by proposing a reference price indexed to liquid to natural-gas prices, which is the main product that low-carbon hydrogen aims to substitute. The premium and the production cost are defined through a double-sided auction. This aims to minimize the public policy funds required to incentivize the low-carbon hydrogen market while facilitating long-term agreements and mitigating price risks that may hinder investment.

Design of a Portable Emergency DC Power Supply

Abstract In recent years, wireless or handheld devices have become increasingly widely used, especially in areas such as environmental monitoring and the Internet of Things. However, due to environmental conditions, they cannot rely on the power grid to provide electricity, and energy supply has become a key issue that restricts the deployment and operation of such devices. This article introduces the method and principle of applying a microcontroller control system to a portable emergency DC power supply, and proposes a method for a portable emergency DC power supply with adjustable and stable output. The output voltage can be adjusted in steps of 0.1-15V. This adjustable portable emergency DC power supply not only has the advantages of small volume and low loss of switch mode power supply, but also has the advantages of small output voltage ripple and good output characteristics of linear power supply. It has certain research significance and practical value.

UPDATED MATHEMATICAL MODEL OF THE TRUNK PIPELINE SECTION WITH LOOPING IN CASE OF LEAKAGE

Pipeline transport is the main method of moving volumes of oil and oil products, as it has several advantages, for example, quality safety and high throughput. At the same time, it also has some disadvantages, which can include the difficulty of increasing throughput without high capital investments and possible leaks and unauthorized tie-ins into pipelines, which are sometimes difficult to identify. Looping is one of the main ways to increase the throughput of the existing pipeline system, when the need to increase the volume of oil and oil products supplies requires the construction of several parallel pipelines — looping. At the same time, the basic mathematical model for calculating the section of the trunk oil pipeline with looping does not fully cover all the physical processes associated with the distribution of flows in the parallel section, which arise due to turbulences in the connection nodes, as well as head loss along the length of the jumpers. Taking into account the resulting flow redistributions, it becomes difficult to detect a potential leak, since any of the detection methods can not solve the problem with high accuracy with determining the leak coordinate with an unknown distribution of fluid flow rates in a parallel section. As part of the study, an updated mathematical model of the oil export pipeline section with looping was developed, which took into account the presence of a potential leak in the parallel section. Mathematical modeling was carried out on the basis of the assumption of a known coordinate, the effect of leakage on the redistribution of flows in a parallel section was estimated. To assess the impact of the leak, various coordinates and volumetric flow rates were set, based on the calculation results, graphs of the flow rate in looping versus its length and internal diameter were plotted. The study is the initial phase of developing a hydraulic location leak detection system for the oil export pipeline section with looping. The need to refine the mathematical model for determining the flow rate in the parallel section is an urgent and necessary task, the solution of which will allow identifying potential leaks with reliable accuracy.

Characteristics of first-time blood donors with unsatisfactory hemoglobin level and positive hepatitis B test in Binh Dinh Province

Blood transfusion is essential in the treatment of a various diseases. In order to guarantee a safe and sufficient volume of blood supply, it is crucial to select appropriate donors based on stringent eligibility criteria. The objective of this study was to furnish robust epidemiological information and identify the risk factors linked to hepatitis B virus (HBV) infection and low hemoglobin levels in first-time blood donors in Binh Dinh. Understanding the causes for donor deferrals can assist better plan and establish an efficient recruiting strategies as well as evaluate donor selection criteria. A cross-sectional study was undertaken in Binh Dinh Provincial General Hospital from November 2022 to February 2023 to examine individuals in their first-time blood donation. Data were sourced directly from voluntary blood donation registration forms. HBsAg results were assessed using rapid immunochromatographic tests and chemiluminescent immunoassays. The rate of unsatisfactory hemoglobin levels was 2.56% tested on 1,638 participants. This rate was significantly associated with female sex (18 times greater odds than males), and lower weight. The results revealed that the rate of HBV infection was 3.13% when detected by the rapid test, but increased by 0.58% when measured by chemiluminescent microparticle immunoassay. The positive hepatitis B deferral correlated with sex (p&lt;0.05), age group (p&lt;0.05) and occupation (p&lt;0.05). HBV was found the leading cause of deferral in the study area and associated with males, age groups (25–35 and 36–44), officer, worker-farmer, and self-employed people. The prevalence of low hemoglobin donor deferral obtained was 2.56%. Low hemoglobin deferral is associated with female gender, lower body weight, worker-farmer, and self-employed - others. This finding underscores a significant public health concerns, highlighting the need for strategies to lower the infection rates. Understanding the factors leading to defered donation can contribute to development of proactive strategies for recruiting and retaining donors.

Does Soil Acidification Matter? Nutrient Sustainability of Timber Harvesting in Forests on Selected Soils Developed in Sediments of the Early vs. Late Pleistocene

With this study, our aim was to estimate the nutrient fluxes relevant for assessing nutrient sustainability as accurately as possible and to calculate nutrient balances for alternative forest management scenarios. Furthermore, we tested whether mapping units from existing geologic maps can serve as a basis for forest practitioners to estimate nutrient sustainability or whether more detailed data are needed. Positive fluxes include deposition and weathering, while negative fluxes include losses due to leaching and nutrient removal through timber harvesting in the balance. Weathering and leachate losses were modeled with a geochemical model. The SwissStandSim model was used to simulate the biomass growth under different harvesting and silvicultural strategies, allowing for sustainability to be assessed for each nutrient at a given intensity of use. This assessment was made per rotation period based on two criteria: (i) nutrient supply and (ii) total stocking volume. As a result, it can be noted that the accurate estimation of individual fluxes is essential for assessing the sustainability of forestry practices and that it needs detailed site-specific data. Various influencing factors turned out to be important, particularly the assumed depth of the root zone.

STRATEGIC IMPERATIVES FOR DIGITISATION OF THE UKRAINIAN PHARMACEUTICAL INDUSTRY

The purpose of the paper is to identify the strategic imperatives of the pharmaceutical industry in the context of the development of the digital economy. Inclusion of the pharmaceutical industry in the list of priority sectors of the economy will help attract state investment support for production and increase the number of jobs. This will help to prevent a collapse in the supply of medicines and medical devices to the healthcare system and ensure their uninterrupted production and supply to the end consumer. The population of Ukraine will have access to quality medicines and medical products. Methodology. The article presents an analysis of the indicators of the pharmaceutical industry for the period 2019-2023. These include the volume of import and export of pharmaceutical products, the structure of the main marketing organisations in the pharmaceutical market, leading drugs in terms of sales volume on the Ukrainian market, the structure of sales of "pharmacy basket" products, and the volume of hospital supplies in terms of funding sources. This paper analyses the main trends of digitisation in the pharmaceutical industry at the global level and in Ukraine in particular. A SWOT analysis was conducted to assess the development of the pharmaceutical industry in Ukraine. The analysis focused on identifying the key factors that contribute to the successful development of e-commerce in the pharmaceutical industry. Results. The publication identifies the main positive and negative manifestations of digitalisation of the pharmaceutical industry in Ukraine and the factors that hinder its development. Practical implications. Thus, the introduction of digitalisation tools in the Ukrainian pharmaceutical industry is an important step towards improving its competitiveness. The deployment of smart manufacturing systems makes it possible to produce medicines faster and more accurately. Such technological solutions can help to optimise the supply chain, which is important for the pharmaceutical industry, where the accuracy and speed of supply of medicines is critical. The use of digital technologies improves control over the safety of pharmaceutical products and increases production efficiency. Automation of business processes through the use of AI, VR, AR, cloud computing, big data, etc. can help reduce production costs and improve product quality. However, the implementation of digitalisation technologies in the pharmaceutical industry also requires significant investments and qualified personnel, which may temporarily reduce competitiveness due to higher prices for finished products.

Evaluation of cooling measures performance and thermal-humidity environment for ultra-high geothermal railway tunnel construction by using WBGT

High-geothermal damage is one of the major challenges in high-speed railway tunnel construction. Current studies have shortcomings in the formation mechanism of tunnel environment and the environment evaluation system. This may lead to an over-optimal environmental acceptability evaluation and jeopardize tunnel construction safety. This study established a mathematical model of the tunnel environment formation mechanism, proposed the wet-bulb globe temperature (WBGT) standard (26.49°C) for the tunnel construction, analysed the cooling efficiency of different environmental control measures. The results show that increasing the mechanical air supply volume can reduce tunnel temperature. Fog cannon can reduce the air temperature near the tunnel working face, the cooling range in front of the tunnel working face is 10.8 m. The cooling shield can control the WBGT below the standard. Under the 90°C rock temperature, the environmental acceptability of the tunnel under pure mechanical ventilation is 0%; the single fog cannon and double fog cannon (both cooperate with double-duct ventilation) are 22.85% and 54.29% respectively; the cooling shield with one fog cannon and double duct ventilation is 95.72%. This study improves the tunnel environment evaluation system during the construction stage, and provides design reference for temperature control measures in tunnel construction. Highlights: Tunnel environment under the impact of multi-physical coupling fields was analysed. Thermal radiation is taken into account in the formation of the tunnel environment. A new benchmark based on WBGT for high-geothermal tunnels construction was proposed. A tunnel environment assessment system was proposed. Cooling shield environmental-control measure was proposed for tunnel construction.

Models for optimising the volume of material flows in the technological chain of corporate vertically integrated structures of the agricultural sector

The relevance of this study lies in the need to optimise supply cycles and volumes in value chains, which helps to reduce costs and increase the profitability of agricultural enterprises. The purpose of this study was to investigate and optimise the costs of initial material flows in the production subsystems of corporate vertically integrated structures of the agricultural complex under conditions of non-stationary demand. To fulfil this purpose, the study investigated the relationship between the amount of raw material stock stored in the production subsystem and the time of its consumption, based on which an extended model of the economic order quantity (EOQ) was considered, which, apart from the defined costs, also considers the costs of raw material shortages associated with the inability to fulfil deliveries and losses associated with supply failures caused by the unpredictability (stochasticity) of the order flow itself. It was found that in continuous production systems there is an opportunity to reduce the costs associated with failures by using an additional regular supply batch. For this, the mathematical “point-of-order” model was built based on the theory of mass service, which allows determining not only the best point to order, but also the optimal amount of the safety stock. A model for optimising the volume of material flows was proposed, which combines the model of the economic order quantity order adapted for use in product subsystems of corporate integrated structures of the agricultural complex and the “point-of-order” model, which allows calculating the minimum size of the insurance stock of raw materials using the tools of operations research. As an example, the material flow was optimised for Kivshovata Agro LLC. The findings of the study, such as the use of analytical tools and models for determining the economic order quantity and safety stock, can be used by the management of agricultural enterprises to improve the efficiency of material flow management

Adaptive stochastic lookahead policies for dynamic multi-period purchasing and inventory routing

We explore a problem faced by agri-food e-commerce platforms in purchasing different, perishable products and collecting them from multiple producers and delivering them to a single warehouse, aiming to maintain adequate inventory levels to meet current and future customer demand, while avoiding waste. Customer demand and suppliers’ purchase prices and supply volumes are uncertain and revealed on a periodical basis. Every period, purchasing, inventory, and routing decisions are made to satisfy demand and to build inventory for future periods. For effective decisions integrating all three decision components and anticipating future developments, we propose a stochastic lookahead method that, in every period, samples future scenarios for demand, supply volumes, and prices. It then solves a two-stage stochastic program to obtain the decision for the current period. To make this approach computationally tractable, we reduce the routing decision in the two-stage program and use an approximate routing cost instead. Given the reduced decision, we then create the final decision via a conventional routing heuristic. We learn the routing cost approximation adaptively via repeated training simulations. In comprehensive experiments, we show that all three components, stochastic lookahead, routing cost approximation, and adaptive learning, are very effective individually, but especially in combination. We also provide a comprehensive analysis of the problem parameters and obtain valuable insights in problem and methodology.