Emergency Protection System Research Articles

MODERNIZATION OF THE WATER PURIFICATION SYSTEM FOR SEWAGE TREATMENT PLANTS USING SCHNEIDER ELECTRIC EQUIPMENT

Currently, the issue of modernization of outdated automatic control systems at strategically important infrastructure facilities of the city, such as water supply and water treatment, is urgent. Using modern automation equipment allows for improving the environmental situation and increasing the reliability of technological processes. This article discusses the development of a new automated system for the biological treatment facility of the Almaty Su sewage treatment plant to replace the outdated current automation. A control system for air conditioning machines, based on Schneider Electric equipment, has been developed using EcoStructure Control Expert software to manage the Modicon M340 controller. Additionally, using EcoStructure Machine Expert, a control system has been created for air injection machines during the biological cleaning phase, which uses the Modicon M241 controller.A process control mnemonic circuit was designed to switch between Modicon M340 and M241 controllers. Remote I/O architectures were developed using the Architecture Builder to create network configurations. An emergency protection system was implemented on Honeywell equipment at Kazakh-British Technical University (KBTU) JSC, using Safety Controller and Manager tools. Security levels at SIL enterprises were calculated.

Research on emergency protection system for personnel safety in cable tunnels based on ultra-wideband

Research on emergency protection system for personnel safety in cable tunnels based on ultra-wideband

ВЫБОР АРХИТЕКТУРЫ И ОБОРУДОВАНИЯ СИСТЕМ ПРОТИВОАВАРИЙНОЙ ЗАЩИТЫ

The issues of justification of application of emergency protection systems, selection of architecture and equipment of emergency protection systems are considered

Diagnostics of failures of technological equipment of chemical industries using artificial intelligence

The paper considers the problem of automated recognition of single emergencies in chemical and oil refining industries. Modern chemical and technological production facilities are maintained and managed by a small number of personnel, which increases the burden on each operator. To reduce the number of operator errors, their training is regularly conducted on simulators equipped with a set of both standard situations (routine start-up, shutdown, normal process management, switching from one mode to another) and emergency scenarios (column depressurization, pump failure, failure of the power supply system). Nevertheless, it is impossible to foresee all possible failures during operator training, and even a trained operator may not notice the first signs of an accident, and therefore it is necessary to create a decision support system that helps the operator to recognize failures of technological equipment in a timely manner. To recognize failures, it is proposed to use a neural network trained on an array of simulated accident data. An industrial simulator based on the RTsim platform was used to simulate typical accidents. The novelty of the research lies in the use of artificial intelligence methods to diagnose the property of the technological process according to the SCADA system and the use of data for training a neural network not from a real object (which will always be insufficient), but from a model that exactly corresponds to a specific technological site. The number of simulated scenarios used to train a neural network can be quite large, which reduces the proportion of erroneous system responses. The developed system confidently copes with the recognition of individual equipment failures. The results obtained can be used to help process operators and to improve emergency protection systems. The analysis of the time required by the system to recognize an emergency situation can be used to design new production facilities, modify the control and management system.

Ensuring Safety of Gas Field Infrastructure Using ALARP and a Systematic Approach

Introduction. A significant part of the global and state economy is the production and supply of hydrocarbon raw materials. The issues of safety in this area will remain important in the coming decades. The problem is actively discussed in the professional and scientific community. Theoretical and applied works are published. Local, point-based methods are calculated and implemented, which allow predicting and preventing emergencies in certain units of the considered objects. At the same time, there are no sufficiently justified and reproducible system solutions that can take into account the state of, for example, oil or gas field as a single complex and act as indicators not only of ordinary local accidents, but also of systemic accidents — catastrophes. Such a scientifically and experimentally based solution is described in this article. The approach is proposed as part of the formation of a comprehensive scientific and technical program (CSTP) to ensure the safety of natural and technogenic objects (NTO). The aim of this work was to describe the practice of its application in the conditions of specific gas fields and to justify the refusal to focus on solutions that took into account only the minimum practically acceptable risk, that is, built on the ALARP principle (as low as reasonably practicable). Materials and Methods. The article was based on the results of field tests of natural and technogenic objects (NTO) of the oil and gas complex — the Yuzhno-Russkoye field of OJSC Severneftegazprom (SNGP), LLC Gazprom Dobycha Yamburg (GDYA) and the gas pumping station (GPS) Orlovka-2 (Ukraine), conducted with the authors’ participation. Significant results were obtained and evidence-based physically interpreted during acceptance tests of an explosion-proof certified, created under the guidance of the authors of a prototype of a disaster response system (DRS) at the integrated gas treatment plant (IGTP) in LLC GDYA in 2006. At the same time, for the first time in the world practice, the fact of early detection and parrying without consequences by means of DRS on the UKPG-2 of the development of a large-scale general industrial disaster was confirmed. In the form of graphs, the revealed patterns of NTO have been visualized, which made it possible to form harbingers of the development of accidents and catastrophes at the NTO of LLC "GDYA", SNGP and GPS "Orlovka-2". Information on the high experimental reproducibility of the obtained results was presented. The technology has been developed of early detection and parrying of all types of potentially dangerous self-exciting systemic phenomena on real NTO infrastructure — self-oscillations. Three cases of their excitation in real gas fields were presented. Results. The paper shows the fragmentary nature and locality of emergency protection systems based on the ALARP principle. The consequence of this was its complete unsuitability for early detection and counteraction to the most large-scale and costly system accidents — catastrophes that were multifactorial processes, in which none of the factors was decisive. The alternative complex solution of the problem proposed by the authors and brought to working condition was based on a system approach adapted to the NTO of the oil and gas complex. The measured parameters of various NTO infrastructure — fields of LLC "GDYA" and SNGP were processed and analyzed at the moments of development of self-oscillating modes on them, due to self-sustaining nonlinear mechanisms of interaction of NTO elements with constant (non-oscillatory) sources of energy replenishment. Three such modes of self-excitation were illustrated. The most informative in this case were the transient modes of operation of the equipment. According to the technologies experimentally developed by the authors, the areas of critical operating modes of equipment with pronounced potentially dangerous bifurcation points were analyzed. The result of superimposing treatments of the measured parameters of eight full-scale tests of NTO — graphs of dimensionless amplitude-frequency characteristics of the interconnections of a real dynamic system was presented: "input — gas cooling housing" → "output — pipe casing" at the frequency of self-oscillations. Discussion and Conclusion. The capabilities of ALARP did not meet the tasks of system monitoring of the occurrence and development of dangerous incidents in gas fields. This conclusion can be attributed to all standard sizes of NTO infrastructure in Russia. Fundamentally different solutions should be used to ensure comprehensive observability, controllability, and safety of NTO. A comprehensive scientific and technical program is recommended: "Innovative hardware and software tools and technologies to ensure the observability, controllability, and safety of the NTO infrastructure of Russia".

Measurements and Influencing Factors of New Rural Collective Economies’ Resilience toward Mountain Disasters in Indigent Areas: A Case Study of Liangshan Yi Autonomous Prefecture, China

Economic activities in disaster-prone areas are significantly susceptible to mountain disasters, and enhancing the resilience of new rural collective economies (RRCEs) is a pressing challenge that needs to be overcome in the areas of disaster risk management and sustainable development. The target research area comprises 48 representative villages in Liangshan Yi Autonomous Prefecture (LP). An assessment framework based on the Resilience Index Measurement Analysis (RIMA) model is established to evaluate the RRCEs in the face of mountain disasters, and the influencing factors regarding the RRCEs are examined. The results show that (1) typical villages in the new rural collective economies (NRCE) have a low level of resilience. (2) Transformational capacity is the key to improving RRCEs. (3) Off-farm villages exhibit the highest level of collective economic resilience, followed by diversified villages, while the lowest resilience level is observed in purely agricultural villages. (4) Talent security and institutional security are important for achieving a high level of resilience. Both of these factors significantly influence RRCEs. (5) The combined influence of talent, financical, institutional, technological, and business security contributes to the diverse factors that shape RRCEs. In other words, the path to achieving resilience in the new rural collective economies is characterized by multiple routes that lead to a common goal. Building on this, we propose recommendations in five key areas, namely, encouraging scientific research and innovation, improving disaster insurance coverage, strengthening the emergency protection system, facilitating collective economic development, and selecting suitable strategies to enhance resilience based on local conditions. The aim is to offer valuable insights for disaster-prone areas to enhance RRCEs and realize sustainable development and rural revitalization.

Investigation of nuclear reactor core thermal-hydraulic characteristics after partial loss of flow accident

In normal operation conditions of nuclear power plants, the distribution of primary coolant between fuel channels would be considered almost uniform. When different number of Reactor Circulation Pumps (RCPs) are switched off, known as an abnormal condition, this uniform distribution is disturbed and different conditions occur for each channel depending on its position in the core. In this research, the normal and abnormal condition (with one or two tripped RCPs) for a VVER-1000/446 is investigated. For evaluation of the core neutronic calculations and thermal power distribution, USNRC’s PARCS system code is employed. Then a thermal-hydraulics module was developed for performing the T/H calculation of the core zone. The input velocity of each channel in abnormal condition was calculated based on developed CFD model in downcomer and lower plenum of Reactor Pressure Vessel (RPV) by ANSYS-CFX. The results show that, in normal operation, the hot channel is related to the central fuel assembly of the reactor core with the highest relative power equal to 1.29 and total power of 23.74 MW. In this case, the minimum inlet velocity, the maximum coolant outlet velocity, and the maximum fuel temperature are 5.6 (m/s), 330.96 (°C), and 1345.8 (°C), respectively. In the cases of operation with one and two tripped RCPs, the hot channel is related to the fuel assemblies with the lowest inlet velocities. The lowest velocities are 0.32 m/s, 0.24 m/s, and 0.22 m/s respectively for the condition with one tripped pump, two tripped pumps placed oppositely, and two tripped pumps placed contiguously. The hot channel numbers in these cases are 158, 102, and 90, respectively. In these channel, the condition of outlet flow would be superheated, but the fuel temperature (1006.3, 1050.9, and 987.9) do not reach the maximum allowable margin. The study confirms the necessity of the coolant distribution consideration in OLCs as well as events that may disturb the symmetry of the coolant flow. It also showed that the lateral fuel assemblies are more at risk in this situation because of a significant reduction in coolant flow. Likewise, the investigations proved the safe continuation of the operation in PLOFA conditions with the preventive algorithm of the emergency protection system and without any need for immediate mitigation actions or operator intervention.

Basics of safety and organization of the workplace during the operation and repair of compressors at the enterprises of ATP

For many decades, any organization involved in the operation and maintenance of vehicles cannot imagine its activities without compressor units. Compressors are used in all sectors of the national economy, and are valued for their reliability, high efficiency, long service life. The scope of the equipment is very wide, without it the work of any large industrial enterprise is indispensable. Compressors are used in mechanical engineering, metallurgy, oil and gas industry, car services, construction and other industries. Each compressor unit is equipped with an emergency protection system that provides: automatic shutdown of the compressor; sound and light alarm. According to the requirements of the Rules, all compressor units are equipped with instrumentation: pressure gauges for measuring pressure, thermometers or other sensors for measuring temperature. The compressor is placed in a separate room, which should not be connected with the premises where explosive and chemically hazardous industries are located. In the premises of compressor units, it is not allowed to place equipment and equipment that are technologically and structurally not related to compressors.

ECONOMIC ASPECTS AND DIRECTIONS OF DEVELOPMENT ENERGY SECTOR IN UKRAINE

The article analyzes that the volume of electricity production in the power industry will increase from 185.2 billion kWh in 2005 to 420.1 billion kWh in 2030 (2.3 times). The dominant role of electricity production at thermal (40.8% in 2005, 39.8% in 2030) and nuclear (47.9 and 52.1%, respectively) power plants will be preserved. At the same time, the production of electricity at hydropower plants will increase from 12.1 billion kWh (6.5%) in 2005 to 14.1 billion kWh (3.4%) in 2030 and at the expense of non-traditional and renewable sources energy – from 0.01 billion kWh in 2005 to 2.1 billion kWh in 2030. The costs of electricity in the power grid for its transportation will be reduced from 14.7% in 2005 to at least 8.2% in 2030, and the specific cost of fuel for the production of electricity in the network – from 378.9 to 345.7 in. / kWh The share of electricity generated from imported fuel will decrease from 58.0% in 2005 to 8.2% in 2030 (7 times) (Fig. 4.5). To ensure these volumes of electricity production, the capacity of power plants has been set at UAH 52 million. kW in 2005 to 88.5 million kW in 2030, including thermal power plants from 30.1 to 42.2 million kW and nuclear power plants – from 13.8 to 29.5 million kW. The capacity of the PSP HPP will be increased from UAH 4.7 to UAH 10.5 million. kW, providing the country’s energy system with sufficient shunting capacity. The construction of main power lines, integrated management and emergency protection systems to increase the capacity of power plants, improve electricity supply in some regions, ensure reliable operation of the Unified Energy System and its integration into the European energy system with increasing electricity exports.

Handling of college students’ network public opinion crisis based on big data analysis

As an important public utility organization and academic research institute, Colleges feature high density people, high social attention, and relatively free atmosphere of interchange ideas, where network opinion crisis are frequent. Therefore, it is critical for colleges to concentrate more on the control and management of the network opinion crisis. In the paper, it compares events of college students’ online public opinion crisis with other references. Social online public opinion crisis solutions is use for reference. Aiming at the peculiarities of college students’ mental health, it is concluded the research coping strategies based on innovative and comprehensive use of big data technology. We establish a complete emergency protection system to effectively deal with the mental health problems of college students.

Оценка быстродействия системы противоаварийной автоматической защиты

Introduction. Emergency protection systems are an indispensable element of modern automated control systems for fire and explosion hazardous technological processes. The protection of personnel, process equipment and the environment depends on their timely operation. Therefore, the methodology for quantifying the performance of the Emergency Protection System in the design and analysis is of undoubted practical interest. Targets and goals. The goal is to develop an algorithm and methodology for quantifying the response time of the protection system in the pre-emergency mode of operation of a technological facility. The tasks include the formation of mathematical models for calculating the time parameters of the elements that make up the Emergency Protection System. Methods. Methods of mathematical analysis and modeling of emergency protection systems are used. Results and discussion. The functions of the Emergency Protection System and the regulatory requirements for their performance depending on their safety class of hazardous production facilities are considered. A generalized algorithm for the formation of the Emergency Protection System is considered, taking into account the requirements for its speed. Using the typical structure of the Emergency Protection System as an example, an expression was obtained for the delay time when it performs the functions of an alarm and the operation of automatic shut-off and shut-off devices. According to technical sources, the approximate time parameters of the elements of the Emergency Protection System are given. The method of quantitative assessment of the response time is considered using the example of an emergency protection system designed to detect gas contamination of a production facility due to depressurization of process equipment, the formation of control signals when the concentration of combustible gases reaches a pre-explosive level, the activation of an alarm, and the operation of valves that block the access of combustible gas to a process facility. Mathematical expressions for calculating the parameters are determined, which allow estimating the total response time of the Emergency Protection System and its compliance with the safety condition for the normatively set time. Conclusions. The considered technique can be used in practice for a preliminary assessment of the response speed of the Emergency Protection System, as well as in the educational process for carrying out practical and laboratory work in the study of industrial automation systems to prevent fire and explosion. Keywords: emergency protection system, protection response time, pre-emergency mode of operation, accident.

Поддержка принятия решений по управлению предаварийными ситуациями на примере установки каталитического риформинга

The article touches upon the problem of reducing the risk of accidents at industrial facilities, which is the priority task of industrial safety management. Currently, accident-free production systems rely on monitoring the process state parameters within the acceptable range and are limited to emergency protection systems, alarms, and locks. However, for complex industrial facilities, it is necessary to recognize pre-emergency situations, which allows predicting the occurrence of an emergency mode and preventing the process from stopping or reducing losses in case of an accident. To solve this problem, a system for managing pre-emergency situations is proposed, which is considered on the example of a catalytic reforming installation. It is based on a method for determining the parametric indicator of the object's state, an algorithm for the proposed system, databases of possible causes of pre-emergency and emergency conditions and a list of measures to eliminate them. This solution allows to set the proximity of the operating mode of the process equipment to the emergency mode, which greatly lowers the risk of accident at the facility, thereby reducing the downtime of the equipment and economic losses.

Pharmaceutical administration practice during prevention and treatment of COVID-19

January 25, 2020, our hospital was served as the designated hospital for critically ill patients with new coronary pneumonia in Wuhan. The timely and effective pharmaceutical emergency protection system was great significance for epidemic prevention. In order to ensure the drug demand of patients and improve the level of drug treatment, the key and difficult issues in the practice of administration during new coronary pneumonia were combined with clinical practical work to develop an appropriate pharmaceutical emergency support system. Our department launched the emergency response mechanism, such as established list of COVID-19 key therapeutic drugs, urgently purchased therapeutic drugs, reformed the processes of emergency pharmacy, established a donated drug management system, establish the COVID-19 pharmaceutical care team, and opened a cloud pharmacy to meet the drug needs of non COVID-19 chronic diseases patients. We also strengthened the management of personnel protection. The administration during new coronary pneumonia is a professional, comprehensive, complex and systematic emergency project that guarantees the safety of drug supply, medication and enables the treatment work to be carried out in an orderly manner. Key words: COVID-19; Pharmacy administration; Clinical safe medication; COVID-19 hospital

Systems for assuring safety of static firing tests of oxygen/hydrogen propulsion units

Static firing tests of oxygen-hydrogen propulsion units with propellant tank load of up to 2700 kg of hydrogen are run with special safety precautions and using emergency test protection system covering up to 60% of contingencies. Test on propulsion units with higher hydrogen propellant loads (up to 7000 kg) require additional safety measures, based on improved effectiveness of the fire and explosion prevention systems, emergency protection, and the coverage ratio for emergency (off-nominal) situations. The key factors for improving off-nominal situations coverage ratio during tests are research into systems for earlier detection of hydrogen leaks and the use of inhibitors with nitrogen as the phlegmatizing agent to prevent explosion of the hydrogen/air (oxygen) mixtures. The paper presents results of studies into systems for early detection of hydrogen leaks and design of monitoring equipment based on fiber optics and microcavity structures that have higher speed of response, selectivity, immunity to noise and reliability. Key words: propulsion system, safety, emergency protection system, off-nominal situation, hydrogen leak, fiber-optic technology.

Emergency Protection System for Women

This venture depicts about a savvy keen security framework for ladies. Ladies everywhere throughout the world are confronting a lot of untrustworthy physical badgering. This procures a quick pace because of absence of a reasonable reconnaissance framework. Our task is a challenge to decide this issue. We are using two things wrist band and shows that are used in regular daily existence. A device takes after the group of a wrist got together by strain key at data impels show the end result shattering alert & noxious gab instrument of a constrained self-opposite reason & send region of a emergency message the contact and moreover comprehend enemy uses exist spouting tape. Nerve chat framework at a live spill capture using webcam is combined into a scenes going as an instrument to the insightful advancement. We genuinely acknowledge of endeavor will have any sort of impact on the female life.

A METHOD FOR OPTIMIZING THE DOSING OF DEMULSIFIER AT A COMPLEX OIL PROCESSING UNIT


 
 
 The process of dosing demulsifier is considered by changing its consumption depending on the consumption of oil emulsin at the installation inlet. The oil emulsion flow ratio and the rate of change of the demulsifier level, which leads to a change in the consumption of the demulsifier, is determined. The proposed process allows to reduce the cost of oil refining by increasing the accuracy of dosing. The whole complex oil processing unit (COPU) is a single block module. The delivery set includes a technological unit, a control unit, furnaces and heat exchangers, automatic furnishing and maintenance units. COPU should be equipped with valves and flow sensors as well as, other means of monitoring, control and regulation, as well as, instruments for testing and emergency protection systems. Operation of COPU control is carried out using an automated system, both remotely and locally. In the process of oil preparation, monitoring and measurement must be carried out the regulation of technological parameters, if necessary. Various comprehensive training facilities correspond to various indicators of economic efficiency, in particular: indicator of energy consumption, complexity of technology; costs of installation, operation, maintenance of installations (including the cost of servicing personnel); the complexity of the oil preparation process.
 
 

Analysis of the reliability properties of duplex structures of emergency protection systems with constant redundancy

The work is devoted to the comparison of two options for the operation of the duplex structure of controllers for the developed methods for assessing the reliability and fault tolerance of multichannel control safety systems and emergency protection systems with incompatible states and a variety of possible options for the sequences of occurrence of obvious and hidden failures with the calculation of the probabilities of these systems being in a working condition in a false state triggers at a given time interval.The problem of ensuring the reliability of information management systems is a complex and complex problem, especially for potentially dangerous technical complexes.For the developed mathematical model for assessing the reliability and fault tolerance of multichannel control systems for safety and emergency protection as systems with elements with three incompatible states: the system is in a healthy state, in a state of false (redundant) operation at a given time interval, it is necessary to compare two options for the duplex structure of controllers.The paper compares two variants of operation of the duplex structure of controllers: Hot StandBy and SA&C.Based on the results obtained, SA & C systems with restoration is a better option compared to the Hot StandBy system with restoration.The results obtained will be used in further studies to obtain dependencies for much more complex structures of automatic protection systems.

ОПРЕДЕЛЕНИЕ КОМПЛЕКСНОГО ПОКАЗАТЕЛЯ ТЕХНИЧЕСКОГО СОСТОЯНИЯ ОБЪЕКТА НА ПРИМЕРЕ БЛОКА СТАБИЛИЗАЦИИ УСТАНОВКИ КАТАЛИТИЧЕСКОГО РИФОРМИНГА

Fail-safety taken as a factor of completeness of using the resources of the production facility is important for characterizing the technological process. In most modern automated process control systems the above factor is implemented by means of the emergency protection system which allows to avoid the progressing emergency. However, such measures significantly increase the downtime of process equipment, since the possibility of developing pre-emergency and emergency situations when combining several permissible and close to emergency values of parameters is not taken into account. To solve the problem of reducing machinery downtime, a method for determining the object state indicator has been proposed. It takes into account all variants of the influence of technological parameters on each other as well as their combinations leading to the emergency progress. As well, the proposed solution helps to set the proximity of the operating mode of the production equipment to the threshold emergency, which greatly reduces the risk of emergency in situ, thereby reducing equipment downtime and economic losses. The method of determining the indicator of the state of the object is considered on the example of the stabilization block of hydrogenate catalytic reforming unit.

Особливості державного управління техногенною безпекою

The article states that the current state of technogenic safety of Ukraine is of concern and requires constant attention from the state regarding the reduction and prevention of emergencies risks. The analysis of tendencies of increase of social and economic losses from natural and man-made emergency situations testifies to the necessity of forming an effective system of management of natural and man-made safety. The author focused attention on the fact that the formation of the system of management of natural and man-made safety should be based on two provisions, namely: the correct establishment of the ultimate goal and the search for appropriate means that provide an appropriate level of such security. The study of selected issues shows the need for effective management in emergencies and improving the effectiveness of the coordination of official government, departmental and nongovernmental activities through the development of a functional structure and the development of managerial skills, but also the transition to a new «management paradigm». It is noted that the management of natural and man-made safety is part of the systemic approach to decision-making, procedures and practical measures in solving tasks for the prevention or reduction of the danger of occurrence of industrial accidents and catastrophic natural processes for human life, diseases or injuries, damage to material values and the natural environment the environment, reducing the negative effects of catastrophic natural processes. At the same time, existing trends in the development of natural and man-made processes in Ukraine necessitate the further development and scientific substantiation of measures to improve and improve the functioning of emergency protection systems as an important part of national security. The construction of the theory of natural and technological safety should be based on a conceptual categorical apparatus that covers the most important aspects of the processes involved in ensuring the safety of complex systems.

Polysilicon Market Development and Production Technologies

The paper considers the current state and prospects for the development of the production of the main material, polycrystalline silicon (polysilicon), used in micro and power electronics and photovoltaics. The dynamics of the polysilicon market dynamics are analyzed. It is noted that the growth in the output of polysilicon is determined by the growing needs of photovoltaics and the global trend towards renewable power generation. It is expected that polysilicon production will grow at a rate faster than 10–15% per annum. For the intensive development of photovoltaics, an important role is played by the development level of polysilicon technology and the availability of this material for the large-scale production of highly efficient solar cells. The main technology used in the industry based on the Siemens process is forecast to remain dominant in the long term. OOO Kremniitechnoprom is developing a state-of-the-art polysilicon production facility based on the original developments and modernization of the Siemens process, which is planned to be implemented in Russia involving leading specialists and enterprises from Germany (SPSC GmbH, GEC GmbH). The new enterprise ensures the maximum production safety, despite the potential risks inherent in the technology, primarily through the guarantee of the performance of modern hardware and process flow schemes, the reliability of the equipment and design solutions, and an emergency protection system. Toxic waste will be processed into safe substances and the end products will be sold. The enterprise will be optimized by key indicators for competitive production, such as the product price, production volume, specific capital investment, and current unit costs.