Abstract on the Master`s work

Contents

1.Relevance of the topic

2. The scientific problem

3. The aim and the main objectives

4. Research methods

5. The novelty of scientific statements

6. The practical significance

7. The main content of the

Conclusion

References

1 Relevance of the topic

Support for cost-effectiveness and safety of the coal industry of Ukraine is one of the main tasks of the state. However, with increasing depth and complexity of the development of economic conditions in which the coal industry to ensure energy independence of the state increased production risks associated with the uncertainty of the geological conditions, reducing the reliability of equipment under the influence of heavy rock pressure, increasing the likelihood of accidents, and with increased volatility financing of projects in post-crisis economy. The vast majority of studies devoted to the analysis of internal and external economic risks of mining production companies, as well as the risks of accidents and injuries. Domestic coal mine project risk is practically not been investigated, although their share is the prevailing view of the specific ground conditions and a high degree of uncertainty of the geological deposits of coal. Under such conditions, adequate internal risk assessment of coal mines is crucial, hence the relevance of the chosen topic of research.

2 The scientific problem

The scientific problem which is solved in this paper is to improve the stability of the defective execution schedule monoproekta coal by internal risk management in the limited time limit and the lack of financial, material and human resources.

3 The aim and the main objectives

The aim is to ensure that the planned production during the current year by eliminating the risk of failure time assembly and disassembly of lava.

The basic idea is to use the law of large numbers and central limit theorem, which regulate the mutual influence of the individual processes of underground coal mining on the extent of the risks of mining.

The object of research are the processes of internal control project risks in underground coal mining.

The subject of research models and methods are internal risk management projects that arise under the influence of stochastic factors, the mining industry.

The main objectives of research are as follows:

1. Identify the internal risks of coal mining. To analyze the mathematical models used to analyze the internal project risk and compliance programs coal mining development project-oriented management style, as well as to analyze the delay timing of assembly and disassembly of lava.
2. To investigate the stochastic parameters of the basic processes of mining development programs as universal indicators of project risks. To study the trends and variations in the rate of preparation and clean-up and their autocorrelation function.
3. Perform a quantitative risk assessment by the stochastic modeling of underground coal mining monoproekta. Risks and to explore its sensitivity to variations of individual factors.
4. Justify recommendations for improving the stability of the defective execution schedule monoproekta coal in confined limits of time and lack of financial, material and human resources through management of internal project risks.
5. Justify the methods of improving information resource monoproekta coal to reduce internal risks. To improve the integrated management of internal risk monoproekta coal.

4 Research methods

We used the following research methods: the methods of statistical analysis and probability theory to study the variation of the load on the working face and the rate of penetration, as well as the study of their autocorrelation, stochastic modeling techniques to identify implementation scenarios monoproekty coal and assess their significance (risk), the methods of artificial neural networks and genetic algorithms for factor analysis, the sensitivity of the project.

5 The novelty of scientific statements

The novelty of scientific statements is as follows:

1. First developed a stochastic simulation model monoproekta coal, which is implemented with the best Sunday time step, based on an exponentially decaying trend of preparatory and continuing trend of clearing works with the variation of the rate, which is consistent with the normal distribution law, and proved the maximum sensitivity monoproekta coal to low-amplitude disturbance factor, whose share in the variation of the terms of the project exceeds 50 %.
2. Clarified the key factors that determine the internal project risks of coal mining.
3. Was further developed understanding of the stochastic interaction of the basic production processes as underground coal mining random events, with the conditional probability, and is a network model monoproekta.

The scientific value of the work is to establish the parameters of random functions and the tunneling rate of sewage treatment works as a composite monoproekty coal, as well as proof of its maximum sensitivity to the factor of low-amplitude disturbance.

6 The practical significance

The practical significance is to increase by 20-25% the stability of the defective execution schedule monoproekta coal mining in the limited time limit and lack of financial, material and human resources by managing the internal project risk by increasing the information resources and commissioning of the project tomography of the rock mass in its investment phase.

The developed method of stochastic modeling of the implementation of projects and methods of analysis of their sensitivity is used in coal mines for the evaluation and management of internal project risks of coal mining, and in the course "Project Management" and "Risk Management" as well as the preparation of master works.

Validity and reliability of scientific statements, confirmed the high level of reliability (at least 90 %), with which the parameters of random functions, reflecting the pace of the main production processes of coal mining, the correct application of the fundamental theorems of probability theory and mathematical statistics for stochastic modeling of these processes, the coincidence of predicted and actual performance of longwall faces with an error not exceeding 24 %.

7 The main content of the

Projects of mining reserves of coal seams are the most risky due to the fact that they are associated with many factors, a high degree of uncertainty. Particularly high uncertainty geological data, which in practice are specified only as mining of the deposit. Typically in a project, there are several factors that have a random nature, and all the factors, or most of their impact on the performance of the project at a time. Therefore, estimation of the overall influence of random factors on the project as a whole is a very difficult task.

In this regard, it developed a new scientific field of risk assessment projects based on the application of stochastic modeling [1-5]. The essence of this approach is as follows. First of all, is justified and developed a mathematical model of the project. After preparing the initial parameters of the model. In the analysis of the program of mining operations at a coal mine as the main parameters used terms of execution of certain works (such as sinking a particular excavation, mining lava, installation of purification equipment, etc.). Then define the critical path of the project or program with a special algorithm. The peculiarity of stochastic modeling is that the problem of the critical path to solve hundreds of times the same structure of the same model. However, at each decision model parameters (duration of individual works) is selected from the pre-defined definitions of laws by the procedure samplinga.

Below is an example of a risk analysis of the program of mining operations on the example of a complex and large mine w/a Pokrovskoye

Figure 1 – Joint United Nations Programme of mining in 2011

To analyze the risks of the program of mining operations for 2011 were prepared and analyzed the following data. The training program inventories and program input-retirement working faces were collected in the general program of mining operations on w/u Pokrovskoye. All work is represented by vectors that are input and output node. Vectors are combined into a graph in the logical sequence that meets the actual sequence of preparation, installation and clean-up operations. For example, the preparation of a southern lava unit 10 for starting, running a team starts with a node (at the time January 1, 2011). At the same time according to the program in January complete tunneling 180m a conveyor roadway south of lava (the vector 1-24), then go 270m mounting Walker (Vector 24-25), and then transferred to the heading team training block 5-7. Installation of a southern lava is a month during April (Vector 25-93), and then begin clean-up activities. At the same time the development of a sewage treatment works in South lava (its acceleration to the design load) is performed for four consecutive months from May to August (Vector 93-95), and after reaching the design capacity of the lava to get to a stable 45tys tons per month (vector 95-98).

According to the earlier spread of the analysis (coefficient of variation), the rate of penetration is planned according to the experience of mine Red Army - West № 1 of the order of 30 %. This level of variation tested on a large representative number of preparatory workings (over 10) and confirmed by the actual performance of other mines (named after Zasyadko, Yuzhnodognbasskaya number 1, they are. Heroes of Space). Sustainable value of the coefficient of variation of penetration rate and the exponential decay rate of the trend with increasing length of the workings of the fundamental laws of evidence, which is caused by the law of large numbers and central limit theorem of probability theory.

When analyzing the risks of the program of mining operations in 2010 used the same coefficient of variation of production rates of the working faces. However, subsequent analysis of the actual performance of the lavas showed that the variation rate is not constant and depends on the current production. In Fig. 2 shows a plot of the variation of production rates from its current value according to some lavas. It was found that the variation decreases according to the exponential dependence of the growth rate of extraction. The indicator of closeness of the connection exceeds 0.9, which indicates a strong link between sustainable production and the absolute value of its variation.

Figure 2 – The dependence of the coefficient of variation of production rates from the current value of its

In this regard, analysis of the program in 2011 was carried out taking into account the established dependence of variation of production rates of its absolute value. He was given the original data file, which encoded the entire program of mining operations, with its parameters and characteristics. In this case it consists of 163 vectors, connected to 98 nodes. Such a graph is possible to analyze a complex only with the help of a computer. In the process of stochastic modeling assessed the possible implementation of critical paths of the graph and their frequency. Due to the fact that the simulation used 200 iterations specified frequencies according to Bernoulli's theorem close to the actual probability of the critical paths found.

In Fig. 3 is a list of critical paths of the program with their probability. First of all, we note that due to stochastic modeling identified 32 critical path, which is about 35 % of the total number of nodes. This is a good indicator because it shows a thorough and balanced program of approximately uniform loading of all the heading, assembly and production teams. If it was a bit critical paths, such as 2-3, it would mean that the program is sloppy, and it has several explicit distortions that are easy to detect critical paths. The more critical paths and the more evenly distributed between the probability, the higher the quality of the program.

Figure 3 – List the critical paths of the program in 2011 and their probability of 32 ways

The following table shows the main critical path with maximum probability. As you can see, the most intense critical path associated with the sinking of the mounting Walker, assembly and testing of two southern lava block 10. 34.5 In the cases referred to the chain of one hundred works is critical.

Table 1 – Characteristics of the most probable scenarios implementing critical paths in a program of mining operations in 2011

Number	Vectors chain	Risk, %	Decoding			Probability
1	-1-43-43-44-44-45-45-46-46-98	26,5	Penetration Walker mounting, installation and testing of two southern lava unit 10			34,5%
2	-1-24-24-25-25-93-93-95-95-98	17,5	Mounting a walker southern lava bl.10	1 south. Lava bl.10		23%
3	-1-29-29-30-30-96-97-98	18,0	Airway six southern lava bl.2,	Mounting southern Walker 6. lava bl.2	6 Southern Lava bl.2	21%
4	-1-83-83-84-84-85-85-98	10,0	Airway three southern lava panel bl 8	Mounting three lava walker south panel bl 8	Three southern lava panel bl. 8	14,5%
5	-1-48-48-49-49-50-50-51-51-52-52-98	3,0	5 south drift conveyor 10 bl	Ventilation Sboyka № 2 5 south lava bl 10	Mounting walker five southern lava bl 10	7,5%
	Only	75,0

With a probability of 23 % can be realized as a chain of critical path work on the preparation and testing a southern lava block 10.

With a probability of 21 % may be a critical sequence of operations, training and working out six southern lava block 2.

Specific concerns related to the preparation and testing of three lava south of the unit 8 (the probability of this critical path is 14.5 %), as well as the preparation of five southern lava block 10, which may not fit into the schedule with a probability of 7.5 %. The remaining critical paths are unlikely and therefore not analyzed.

Despite the identified critical path at first glance, they should not cause concern. Since the preparation and installation of two southern lava unit 10 is performed in a timely manner, and its dispersal to the design load even faster than the planned time frame. The distribution of even the late timing of the planned annual production does not exceed 48 weeks, the year (Fig. 4). This creates a false impression about the reliability of the program of mining operations in 2011.

Figure 4 – The earliest and latest completion dates of the planned production in the southern two longwall block 10 in 2011 (in weeks)

There are several reasons. First, a program was compiled on the basis of the hypothesis of favorable geological conditions of mining. However, only in the southern wing of the block 10 is first lava (4 South) faced the problem of transition of low-amplitude disturbance, which is represented by substitutions coal seam solid sandstone. It is seen that as the entry of lava into the zone violations are gradually falling rate of podviganiya that is natural, since an intensive wear of downhole equipment and the powered supports. Moreover, it should be a high degree of certainty that on these sections of the geological conditions are even worse because they are located in close proximity to Kotlin thrust.

Unfortunately, there is a significant negative factor, which has not yet taken into account in the program. This is a paired 1 and 2 of the southern lavas. It is well known that working out twin lava, ceteris paribus less reliable than practicing each separate lava in isolation and in complex geological conditions is associated with increased risk. This is evidenced by the experience of working out 5 and 6 of the southern block of n c lavas 8.

There are also increased risks of working out six southern lava block 2, as its pillar excavation is located directly at a large disjunctive.

In drawing up the annual program were also admitted some inaccuracies. So some of the lava was planned to put into operation immediately after the sinking mounting the camera. The U.S. has a long experience in installation of lava within two to three days, but the practice of installation, the Red Army at the mine - Western number 1 indicates that the most likely period of installation of purification equipment is about two months. With this in mind, the periods of installation have been increased, resulting in a planned annual production fell to 4765.0 thousand tons instead of the planned 5110.0 thousand tonnes. If you try to squeeze production shortfall in the program, inevitably there will be new critical path and deadlines targets are displaced substantially upward.

The authors of the research was carried out special work to be able to establish the actual time of installation of longwall faces. In this paper we compared the data monthly podviganiya development faces, the actual time of their completion and time of entry longwall faces in operation. The difference in these terms was calculated the actual time taken to carry out assembly work in the slaughter of abatement.

Table 2 – Performing work on the installation of newly longwall faces shutdown and dismantling of lavas

Name of work	Unit. rev.	The volume of	Dress for a day	In fact, for a day	+ /- Per day	Only		+ /- To schedule	Residual volume	The reason for failure to specify a day. Notes
						according to the schedule	on the fact
Assembly work:
Lava 1. Performs work site of MAO-1.
Mounting boards coal face conveyor CZK228/800	Pieces	204	7	7	0	204	154	-50	50
Delivery of support units 3KD-90	Pieces	204	2	2	0	104	62	-42	142	Work on installation of the sections being behind schedule due to delays in the preparation of the southern conveyor roadway (development over which the delivery of equipment)
Installation of roof support sections 3KD-90	Pieces	204	2	2	0	102	62	-40	142
Mounting brackets for bolting sections 3KD-90	Pieces	408	4	4	0	204	118	-86	50
Installation combine CF-450	%	100	10	10	0	100	100	0	0	Works on installation of two worms, produced by cutting the cable installation
Lava 2. 1st conveyor drift lava 2. Performs work site of MAO-4
Reinstalling beams DP road diesel	m	1700	70	70	0	700	620	-80	1080
Lava 3. 1st conveyor drift lava 2. Performs work site of MAO-4
Delivery of pipes Ø426мм (degassing)	Pieces	340	8	8	0	152	144	-8	196
Installation of pipes Ø426мм (degassing)	m	1700	70	70	0	700	610	-90	1090
Dismantling:
Lava 4. Performs work site of MAO-1.
Removing the lining sections of the ICJ	Pieces	204	1	1	0	92	42	-50	162	The cost of removing the sections being behind schedule due to difficult geological conditions.
Fixing dismantled space	m	310	2	2	0	130	76	-54	234
Issuance of support units MKYU.4U 5 yuzh.konv.shtreku ts.p. bl.8	Pieces	310	2	2	0	130	76	-54	234
Lava 5. Performs work site of MAO-4
Removing the support units 3KD-90	Pieces	100	1	1	0	100	76	-24	24	The work of dismantling and delivery sections are performed behind schedule due to busy main road on the monorail which is delivery of materials and equipment for mining and tunneling faces.
Issuance of support units 3KD-90	Pieces	100	1	1	0	100	61	-39	39
Fixing dismantled space	m	150	2	2	0	150	147	-3	3
Conveyor Works performs crosscut section of MAO-4
Removing the belt 2nm-100	%	100	5	5	0	85	85	0	15	Work is underway to dismantle the drive station number 2
Issuance of used mining equipment		t	50	4	4	0	35	31	-4	19
Lava 6. Work station performs UGMR-4
Removing the lining sections 3KD-90	Pieces	63	2	2	0	52	37	-15	26	The cost of removing the sections being behind schedule due to difficult geological conditions (rock dumped observed along the entire length of lava, which makes removal and attachment of the developed space).
Lava 7. Performs work site of MAO-4
Pumping water from the vent Walker bl.2 and 6 south drift conveyor bl.2	during the day	63	24	24	0	24	24	0	0

According to a representative sample of evidence, drawn from the experience of recent years, the average installation time stope was 3.6 months or 15.5 weeks. The coefficient of variation time of installation is 0.38. Economic calculations have shown that in order to ensure sustainable and profitable operation of the mine is necessary that the time of installation should not exceed two months.

Data analysis of the mine dispatch logs revealed that there are a number of factors that affect the timing of the delay assembly-disassembly lavas. Table 1 shows the typical causes of delays in terms of a typical installation of a long working face. In particular the installation of a lava behind the planned volume by 31 % due to delays in the preparation of a second conveyor roadway (development over which the delivery of equipment), the first conveyor roadway second and third lava – by 11.5 %. Works associated with the dismantling of pollution control equipment have a higher percentage of the backlog of planned compared with the assembly. Thus, in four because of the lava complex mining and geological conditions of work behind at 48.7 %, in the lava 5 – by 18.9 % due to busy main road on the monorail which is delivery of materials and equipment for mining and tunneling faces in 6 due to severe lava rock dumped along the entire length of lava at the – 28.9 %. These data illustrate just that dismantling works could be a decisive element in shaping the critical path merchandising major and minor processes of coal mining.

This is natural, since the high risks of failure in the program as if the plan is the shortage of resources (time, human power, finance, underground space) as well as assignments to rigid deadlines. It is proved that the program drawn up for the tough terms of performance (ie, to perform at any cost by the due date), other things being equal, always more expensive, provide less quality results and are more likely to relapse compared with programs planned for fixed periods of performance of individual works (ie have to perform after you're done, but packed in a given period of time).

Conclusion

Planning the annual program of mining operations should be carried out taking into account the adverse effects of geological and mining conditions of mining stocks. You must have a method of forecasting parameters and coordinates of small-amplitude disturbances at least within the excavation column adjacent to the waste before the lava. Further study will clarify the terms of the distribution of assembly and disassembly of longwall faces. This is to improve the reliability of the forecast risks of the program as a whole.

References

1. Шапиро В.Д., Управление проектами. Москва изд. «Два Три», 2003, – 526 с.
2. Ильяшов М.А., Мерзликин А.В., Оценка устойчивости работы очистных забоев по параметрам распределения добычи – Материалы международной научно-практической конференции г. Днепропетровск НГУ 2011. С. 52–63.
3. Захарова Л.Н., Исследование чувствительности программы развития горных работ и ее рисков в условиях угольной шахты, – Радіоелектронні і комп’ютерні системи, 2012, № 1(53). – С. 1-8.
4. Вентцель Е.С. Теория вероятностей. – М.: Наука, 1964. – 576 с.
5. Свешников А.А. Прикладные методы теории случайных функций. – М.: Наука, 1965. – 432 с.
6. Clemen, Robert T. and Reilly, Terrence. Making Hard Decisions with Decisions Tools: Duxbury Thomson Learning, 2000.