Improvement of the grain cargo handling technology on the basis of resource-saving

The article considers the state of grain cargo transportation and related technical and technological problems. As a solution, the possibility of using multiple grain shipping containers and the introduction of a new modern grain cargo handling technology at the station based on inventory management and proper selection of vehicles was considered. The considered measures will contribute to simplifying, improving and reducing the number of cargo operations performed during grain handling, making their implementation more practical and energy-efficient.


Introduction
Grain cargo transportation takes a significant volume in the range of cargoes carried by transport and is one of the strategic products offered by the Ukrainian economy today. Grain has a significant impact on the development of the agricultural sector and is the main export product of the country. Grain cargo is mainly exported through seaports, while grain is delivered to ports mainly by rail (61%), road (36%) and river transport (3%). Therefore, the purpose of the article is to study the methods of loading grain cargo into a vehicle and organize optimal conditions to obtain the most effective quality indicators.

General part
The volume of grain cargo transportation is constantly growing [1]. The paper analyzes statistical data on the volume of grain and milling products transportation from 2009 to 2020 ( Figure 1) [2]. The analysis shows that the volume of transportation has still been growing until now. Therefore, the transportation technology always has some shortcomings and, accordingly, the task arises to develop new resource-saving technologies.
The main problems in the grain transportation are: seasonal shortage of grain cars [3] and imperfect technology of grain loading complexes when such goods are transported in containers. The issue of seasonality of this cargo is considered in the model of cargo rolling stock management, which takes into account the parameter of uneven transportation [1].
The use of containers for loading grain has very good prospects, especially in the organization of export transportation, as labor-intensive and time-consuming cargo transshipment in ports are thus avoided [4]. Also, fewer grain cars which are not always available are required and more platforms are IOP Publishing doi:10.1088/1757-899X/1021/1/012006 2 used to transport containers, that are much cheaper than grain trucks and more versatile at any season. In addition, the likelihood of using containers increases that usually return empty after unloading in areas where grain cargo may be loaded. One of the most important components in the entire cargo delivery chain is the organization of container loading at the points of departure. The loading technology for grain transportation containers can have various forms. Containers can be loaded directly on the site of the cargo owner and delivered to the railway station by vehicles designed specifically for container transportation, or grain cargo can be delivered by the owner directly to the grain warehouse of the station, where containers will be loaded and then placed on railway platforms. In [5,6], the optimal placement of infrastructure facilities for primary grain handling is considered, while the feasibility of using various types of transport and forming an effective chain of grain transportation is discussed in [7,8].
Therefore, the task is to develop a resource-saving technology for loading grain cargo, which will take into account as many factors as possible that influence the total cost of transportation, such as the number of loading and unloading machines (LUM), the number of deliveries to the warehouse complex and its operating time a day [9,10].
To formalize the extreme task of improving the grain handling technology, a model of the functioning of the cargo front line (grain warehouse) has been developed.
To build a model, operating cost during performing work was selected as the optimization criterion, as it is one of the most important resource-saving components (table 1). The controlled parameter of the system is the handling capacity of the cargo front line Qp, determined by the number of LUM M, deliveries of cars to the cargo front line Y, and the operating time during the day T. The problem of choosing a rational version of the operating technology for grain cargo handling is formulated as follows: for the specified characteristics of the input flow of requirements and the type of service system, parameters should be determined that correspond to the minimum value of the optimization criterion Ri.
Additional complication is the fact that there may be more than one option of the warehouse operation, depending on the capacity of the handled containers per day, the handling capacity of LUM per day, and the warehouse capacity. Therefore, the following conditions are taken into account when the optimal operating technology is determined: cars are delivered to the warehouse by routes.
is the probability that the capacity of containers handled per day is less than the handling capacity of LUM per day; is the conditional probability of the event in which the amount of cargo in a single serve is less than the storage capacity provided that the capacity of containers handled per day is not more than handling capacity for LUM per day, i.e.
is the probability of the volume of cargo in the delivery not exceeding the warehouse capacity; ); ), ) ( )  the capacity of containers handled per day is greater than the handling capacity of LUM per day, the warehouse capacity is insufficient for storing cargo ). ), ) ( ) Rate setting condition:  are assumed to be equal to one.
The continuity and reliability of the handling process depends on the level, rational use of the available equipment and the adopted technology. The conditions for the smooth operation of subsystems are determined by the load level of the interacting channels, which are calculated using load intensities.  ; 24 Since each component of the function is a complex functional, the article shows the model implicitly. The function will further be considered explicitly.
As an example, the optimal functioning parameters of the grain warehouse based on a specific railway station are estimated. The obtained results are shown in the Figure 2. The results of estimations proved the presence of the extreme minimum, which allows us to determine the optimal number of loading and unloading machines, the number of deliveries and the operating time of the warehouse complex during the day, both in the stand-by and operational mode.
The proposed approaches can be used for the operational adjustment of the current situation, taking into account the predicted arrival of grain cargo for loading. It can be integrated into the decision support system in the corresponding automatic workstations of operational employees of the station: the station attendant, shunting dispatcher, acceptance/delivery inspector, process engineer, and others.

Conclusion
The volumes of grain cargo transportation and their seasonality have been analyzed. It is found that during peak loading periods there is an acute shortage of grain cars. Therefore, one of the ways to eliminate this shortage is to use grain shipping containers.
Possible variants of grain warehouse operation are determined, that take into account the ratio of the main parameters that affect the warehouse operation, including container capacity, warehouse capacity and handling capacity of LUM.
The operation technology of the departure point for grain cargo handling is formalized on the basis