Declarative Modeling of Multimodal Cyclic Processes

The article analyzes the actual problems of prospects of logistical support of transportation of products. Automobile, railway, aviation and water modes of transport, which function and develop according to different rules and criteria, based on their departmental interests and priorities, were investigated. Conquesting and retaining competitive advantages is relevant for any mode of transport in our country at this stage of economic development. The main directions for strengthening the state transport policy which is necessary to supplement and adjust the actions of market mechanisms in order to ensure the effective, public­interest formation of the state transport system and the transport services market, were formed in this article. A possible solution to the problem is the unification of hundreds of medium-sized and small motor transport companies and freight forwarding companies in one place - a multimodal transport and logistics center with the provision of logistics services. This will attract new investment in the country's transport infrastructure and increase the level of logistics services. The object of study - the process of logistical support for transportation of products. The purpose of the study is to analyze the problems of interaction and competition between different modes of transport in the modern conditions and to identify possible directions for their solution in the transport of goods and passengers in order to ensure stable economic development, satisfaction of the needs of the population and social production. Methods of research - methods of economic, system and comparative analysis. On the basis of the analysis of the interaction of different types of transport, it was discovered that during this time the cardinal transformational processes from the socialist plans to market relations and infrastructure development took place in the state economy. The specificity of activity of different modes of transport is that they not only interact, but also compete with each other in the provision of transport services. There is a big competition at the interstate level for the transit of goods. It is proved that for further growth of grain export, it is necessary not only to improve the logistics of transportation, but also to develop the infrastructure of the country. It would be appropriate to consider at the state level the possibility of prioritizing the transportation of agricultural products by different modes of transport during the peak period and to develop programs to encourage the construction of modern grain storage facilities in port areas and at the borders of Ukraine with neighboring countries. Expected assumptions about the development of the object of study - a logistic approach for sustainable economic development is proposed, conquesting and retaining competitive advantages which will allow to promptly take into account changes of the environment, to respond to the behavior of competitors and consumers, that is, provide for and form demand and supply in the prospective plan. That is why it is necessary to carry out complex measures aimed at transforming any company into a successful commercial enterprise, which will provide high-quality transport services. In general, the strategic goal is to solve three main tasks: to reduce the company's expenses, increase its income and ensure the maximum safety of movement and safekeeping of cargoes during transportation both on the territory of our state and abroad. KEYWORDS: LOGISTICS, COMPETITIVENESS, TRANSPORTATION OF RODUCTS, THE TRANSPORT SYSTEM OF THE COUNTRY, LOGISTIC SYSTEM, STATE TRANSPORT POLICY.

The paper treats about a grid-like topology of different means of transport acting in mesh-like streets network in which several modes interact each other via common shared hubs (i.e. stops, interchange stations, cross-platforms, etc.) as to provide mass customized passenger services, tailored to each travel destination. In that context, a grid-like layout of various transport modes such as tram, bus, train, subway where passenger flows are treated as multimodal processes can be seen as a real-life example of the considered case. The goal is to provide a declarative model representation enabling to state a constraint satisfaction problem aimed at multimodal transportation processes scheduling aimed at dedicated flows of passengers service. The main objective is to provide conditions guaranteeing the right match-up of local cyclic acting tram/bus/metro line schedules to a given passenger flow itineraries.

The cyclic scheduling problem modeled in terms of Cyclic Concurrent Process Systems is considered. The problem can be seen as a kind of Diophantine problem, hence its solvability, i.e. schedulability, plays a pivotal role in many supply-chain problems. In contradiction to the traditionally offered solutions the approach proposed allows one to take into account such behavioral features as transient periods and deadlocks occurrence. So, the contribution’s aim is the modeling framework enabling an evaluation of cyclic scheduling problems solvability, i.e., the declarative approach to reachability problems regarding cyclic steady states determination as well as conditions guaranteeing assumed performance of multimodal processes executed within a concurrent cyclic processes environment.

The challenges facing transport companies in the era of global competition for customers form the conditions for creating various forms of cooperation with varying degrees of integration, both within one mode of transport and between different modes of transport. The article discusses the foreign experience of creating various alliances both within one mode of transport and between different modes of transport. The world experience in implementing various methods of cooperation, which allows adapting the route network to modern realities, increasing the mobility of the population and reducing the cost of the trip, deserves attention and study for its use in the 1520 space. Creating such an alliance (“1520Team”), subject to the maximum integration of carriers with unified service classes, a route network with developed interchange services, integration with other modes of transport, will form the foundation for building new relationships, allowing to bring the transport services market to a new qualitative level.KeywordsCooperation on transportVarious forms of cooperationAlliancesA fight for a customerDeveloping the transport market

Urban traffic is closely related to the daily life of the public,and air pollution in the traffic microenvironment has become a public health problem that cannot be ignored.This paper reviews the comparative studies of air pollutant exposure levels among different modes of transportation in multiple cities in China.By comparing the exposure levels of pollutants among different modes of transportation,this paper provides a reference for protecting the health of the public in daily transportation and selecting targeted control measures.

Improving the efficiency in the links in the supply chains of agri-food products is relevant in terms of the assessment methodology and practical aspects for ensuring and supporting sustainable supply chains of products not only in individual channels of product movement but also in the end-to-end supply chain of products, i.e., from the field to the end consumer. However, it is still unclear which supply chain opportunities in commodity distribution channels are more effective for creating end-to-end sustainable supply chains for agri-food products. The purpose of the study is to develop a methodology for assessing the impact of agri-food supply channels on the efficiency and link in supply chains, taking into account the factors affecting them and developing recommendations for their improvement. Quantitative methods based on correlation and regression analysis using the EViews program on the basis of Kazakh statistical data for 2008–2022 were used. A methodology is proposed for assessing the effectiveness of the functioning and links in commodity movement in the supply chains of agricultural products at the macroeconomic level based on the consideration and use of important factors affecting the efficiency and links: production and sales volumes, total costs, and profitability for each supply channel: “production–processing–industrial production–trade”. The relationship between the efficiency and the links in supply chains and also the key factors that affect them have been established. The results showed that the increase in the efficiency in supply channels in the commodity distribution system leads to a decrease in the coefficient of the link in commodity movement and inventory availability. To reduce the link ratio in the supply chains of agri-food products, it is necessary to increase the efficiency in supply chains in each supply chain link and reduce the share of retail trade in the gross turnover. Recommendations are proposed to improve supply chain efficiency and reduce links to support and create end-to-end sustainable supply chains of agri-food products. The study makes an essential contribution to providing empirical evidence of the relationship between the effectiveness of agri-food supply channels and the link in the supply chain. Since few works describe the relationship between the links of product distribution and the efficiency in supply chains in the literature, in this work, it was possible to propose a methodology and identify factors and gaps in research to identify potential areas for future research.

In this paper, an incentive scheme based on crashing lead time is proposed to coordinate a supplier-retailer supply chain (SC). In the investigated SC, the supplier applies a lot-for-lot replenishment policy to replenish its stock and determines the replenishment multiplier. Moreover, the transportation lead time is considered under the control of the supplier. The retailer as downstream member manages his inventory system according to the periodic review replenishment system (R, T). The review period (T) and order-up-to level (R) decisions along with the retail price are simultaneously optimized by the retailer. These decisions are made by the retailer influence the profitability of SC as well as the supplier's profitability. The investigated SC is modeled under three different decision making structures, i.e., (1) decentralized decision making model, (2) centralized decision making model, and (3) coordinated decision making model. By developing a lead time reduction policy as an incentive strategy, the pricing and periodic review replenishment decisions are coordinated. In the proposed incentive approach, the supplier by spending more cost and changing a fast transportation mode aims to crash the lead time in order to entice the retailer to accept the joint decision making strategy. In the suggested incentive scheme, two transportation modes (one slow and one fast) are supposed. Further, maximum and minimum lead time reduction, which are acceptable for both members, are determined. Moreover, a set of numerical examples along with a real case are carried out to demonstrate the performance and applicability of the developed models. The results demonstrate that the proposed incentive strategy is able to achieve channel coordination. Moreover, the results show the applicability of the developed coordination model under the high demand uncertainty. In addition, the proposed coordination model will fairly share the obtained profits between two SC members.

The paper concerns cyclic scheduling problems arising in a Multimodal Transportation Network (MTN) in which several unimodal networks (AGVs, hoists, lifts, etc.) interact with each other via common shared workstations as to provide a variety of demand-responsive material handling operations. The material handling transport modes provide movement of work-pieces between workstations along their manufacturing routes in the MTN. The goal is to provide a declarative framework enabling to state a constraint satisfaction problem aimed at AGVs fleet match-up scheduling taking into consideration assumed itineraries of concurrently manufactured product types. In that context, treating the different product types as a set of cyclic multimodal processes is the main objective to discuss the conditions sufficient for FMS rescheduling imposed by production orders changes. To conclude, the conditions sufficient for an FMS rescheduling imposed by changes of production orders treated as cyclic multimodal processes are stated as the paper’s main contribution.

A declarative model aimed at reachability-driven refinement of the multimodal networks (MNs) cyclic steady state space is proposed. The concept of multimodal processes executed in goods/passengers transportation or data transmission networks where several closed loop structure subnetworks interact each other via distinguished subsets of common shared hubs as to provide a variety of demand-responsive goods or data transportation/handling services is employed. Multimodal processes throughput depends on their cycle time that is on cycle time reachable in considered MN. Therefore, searching for the MN’s cyclic steady state behavior the following question is considered: Is the cyclic steady state space reachable in the given network structure? The declarative approach employed makes it possible to evaluate the reachability of cyclic behaviors on a scale that reflects real practice.

There has been an increase in the network of mass rapid transit (MRT) and the number of automobiles over the past decades in the Taipei metropolitan area, Taiwan. The effects of these changes on PM2.5 exposure for the residents using different modes of transportation are unclear. Volunteers measured PM2.5 concentrations while commuting in different modes of transportation using a portable PM2.5 detector. Exposure to PM2.5 (median (range)) was higher when walking along the streets (40 (10–275) µg/m3) compared to riding the buses (35 (13–65) µg/m3) and the cars (15 (8–80) µg/m3). PM2.5 concentrations were higher in underground MRT stations (80 (30–210) µg/m3) and inside MRT cars running in underground sections (80 (55–185) µg/m3) than those in elevated MRT stations (33 (15–35) µg/m3) and inside MRT cars running in elevated sections (28 (13–68) µg/m3) (p < 0.0001). Riding motorcycle also was associated with high PM2.5 exposure (75 (60–105 µg/m3), p < 0.0001 vs. walking). High PM2.5 concentrations were noted near the temples (588 ± 271 µg/m3) and in the underground food court of a night market (405 ± 238 µg/m3) where the eatery stalls stir-fried and grilled food (p < 0.0001 vs. walking). We conclude that residents in the Taipei metropolitan area may still be exposed to high PM2.5 during some forms of commuting, including riding underground MRT.

The main direction for improving the efficiency of cargo transportation is the implementation of combined road-rail transportation. The difficulty in of solving this problem arises from the various conditions that occur when transporting goods by different modes of transport. There are several options for organizing transportation, namely: Option 1 - transporting goods to the railroad, transshipment and further transportation by rail, Option 2 - transportation by road in parallel with rail. The aim of this research is to develop a mathematical model for combined transportation on the transport network, using both road and rail transport with transshipment from one type of transport to another. The research was conducted using the methodology for dual problems of linearly constrained optimization, makes it possible to establish the existence and finding a solution to the stated problem. The results of this work can be used in information systems for decision-making by cargo shippers regarding route selection in the field of cargo transportation under conditions of competition or interaction between different modes of transport.

Seamless traveling allows individual travelers to extend their mobility radius and – by combing different modes of transport – to use travel time more efficiently. This can result in various advantages on the side of the traveling individual. Caused by more convenient trip planning, it also can result in more trips or in case of disadvantageous combination of travel modes that are not environmentally friendly hence, it also can lead to higher energy consumptions and more emissions. But a central advantage is obvious. A combination of environmentally friendly modes reduces the private car usage. Three European projects were exploring how this can be turned into reality. The assessment of their (interim) results tries to scrutinize major findings on how to realize more multimodality within Europe observing three different spheres: political, informational (traveler) and urban transport planning sphere.

How accurately does the public perceive differences in transport risks?: An exploratory analysis of scales representing perceived risk

California is aggressively moving forward with efforts to deploy zero-emission transportation technology to fight climate change, especially the Greenhouse Gas (GHG) emissions from the high-impact transportation sector. However, to date, the investments California has made with Cap-and-Trade funding have focused on ground transportation and some marine sources and not the aircraft at the over 140 airports in the state. Through a California-focused comprehensive GHG emissions analysis, this research project seeks to determine how RAM using electric/hybrid electric aircraft can provide new high-speed transportation for high-priority passenger and cargo movement within Fresno County and connections to coastal urban centers. Using VISION, a model developed by the Argonne National Laboratory Transportation Systems Assessment Group, the research team identified and compared the emission per mile and emission per passenger mile between different modes of transportation using traditional petroleum fuel and other sustainable alternatives at an individual level and within the context of the transportation sector, by comparing different modes of transportation. With this estimation on hand, it becomes more viable for the state of California and other states, as well as the federal government, to establish guidelines and goals for transportation policies and investments.

The idea of Sustainable development has gained more attention since it involves satisfying needs without degrading the environment. Sustainable development has many targets across various subjects in which Sustainable Transportation is one of the cores to sustainable development. The objective of sustainable transportation is to achieve social, environmental and economic growth with universal access, enhanced safety, improved resilience and infrastructure, reduction of emission in greenhouse gases, traffic management, freight management by different modes of transportation. It is vital and interlinked across several sustainable development goals (SDGs) and targets in the 2030 Agenda proposed by United Nations. There is a need to improve sustainable transportation, which can be achieved through artificial intelligence as it helps the sector to increase public transport, traffic safety, reduce accidents and improve traffic management, decrease carbon emissions, rise reliability and also leverage economic growth through methods like Fuzzy logic (FL), Artificial Neural Networks, Ant Colony Optimiser, Genetic algorithms, Swarm optimization algorithm, Simulated Annealing. It is also supported by Big Data Analysis, Internet of Things, Robotic process Automation. This paper addresses the overview of the importance of sustainable transportation along with the role of artificial intelligence in different modes of transportation, current level of sustainability across globe, progress in transport system and conclude with challenges and future improvements that can be made towards the goal.