Management Of Complex Systems Research Articles

Subspace dynamic-simplex linear interpolation search for mixed-integer black-box optimization problems

Design and management of complex systems with both integer and continuous decision variables can be guided using mixed-integer optimization models and analysis. We propose a new mixed-integer black-box optimization (MIBO) method, subspace dynamic-simplex linear interpolation search (SD-SLIS), for decision making problems in which system performance can only be evaluated with a computer black-box model. Through a sequence of gradient-type local searches in subspaces of solution space, SD-SLIS is particularly efficient for such MIBO problems with scaling issues. We discuss the convergence conditions and properties of SD-SLIS algorithms for a class of MIBO problems. Under mild conditions, SD-SLIS is proved to converge to a stationary solution asymptotically. We apply SD-SLIS to six example problems including two MIBO problems associated with petroleum field development projects. The algorithm performance of SD-SLIS is compared with that of a state-of-the-art direct-search method, NOMAD, and that of a full space simplex interpolation search, Full-SLIS. The numerical results suggest that SD-SLIS solves the example problems efficiently and outperforms the compared methods for most of the example cases. © 2017 Wiley Periodicals, Inc. Naval Research Logistics 64: 305–322, 2017

Systemic solutions for systemic problems

The systems sciences and cybernetics emerged in the years after World War II. These fields created many new approaches to engineering and management and contributed new ideas to existing academic fields. The new fields also identified similar concepts across a range of fields and began to create a general theory of systems. In addition the systems sciences created a variety of methods for managing complex systems, for example logistics, operations research and computer simulations. In the 1970s there was concern about population and environment balance. Currently there is increasing concern with governance, since the rate of presentation of problems seems to be greater than the ability of our institutions to manage them. This paper will discuss the history of systems science and cybernetics, the questions formulated and the solutions proposed, the difficulties encountered in finding a home within contemporary universities and some exciting lines of research now underway.

Parallelizing highly complex engine management systems

SummaryThe automotive industry seeks to include more and more features in its vehicles. For this purpose, the necessary policy shift towards multi‐core technology is in full swing. To eventually exploit the extra processing power, there is much additional effort needed for coping with the tremendously increased complexity. This is largely due to the elaborate parallelization process that spans a vast search space. Consequently, there is a strong need for innovative methods and appropriate tools for the migration of legacy single‐core software. We use the results of a data dependency analysis performed on AUTOSAR system descriptions to determine advantageous partitions as well as initial task‐to‐core mappings. Afterwards, the extracted information serves as input for the simulation within a multi‐core timing tool suite. Here, the initial solution is evaluated with respect to proper scheduling and metrics like cross‐core communication rates, communication latencies, or core load distribution. A subsequent optimization process improves the initial solution and enables a comparative assessment. To demonstrate the benefit, we substantially expand a previous case study by applying our approach to two complex engine management systems and by showing the advantages compared to a parallelization process without preceding dependency analysis and initial partition/mapping suggestions.

Complex systems modeling with intelligent control elements

The approach to managing complex systems through the usage of fuzzy technology in combination with the system-dynamic modeling is improved. The methods of system dynamics and artificial intelligence represented the research subject. Object of study includes process operation of complex systems. For the experiment selected banking system (BS) and commercial bank (CB) as its subsystem. The mathematical models of the BS and CBs are developed; elements of intelligent control are formalized. The knowledge base in the form of production rules is designed in the paper. Functions of fuzzy variables and their parameters are selected for building fuzzy models using Mamdani and Sugeno algorithms. The control impact and the functioning of intellectual decision support system for the prediction task are studied. The efficiency of scientific research on the example of the Ukrainian BS is evaluated.

Questioning a “one size fits all” city brand

PurposeCity branding has gained popularity as governance strategy. However, the academic underpinning is still poor, and city branding needs a more critical conceptualization, as well as more complex management systems. This paper challenges the use of a “one size fits all” city brand, which is still common practice in many places. The paper proposes that city branding involves much more complexity than is commonly thought and outlines a strategy that enables urban policy-makers, marketing researchers and (place) marketers alike to better deal with city branding.Design/methodology/approachThe authors integrate insights from literature on place branding, brand architecture and customer-focused marketing.FindingsThe article argues that place brands (in general and communicated place brands in particular) are by definition very complex, due to their different target groups, diverse place offerings and various associations place customers could have. Thus, an advanced brand management including target group-specific sub-brands is needed.Practical implicationsThe model will be helpful for place brand managers dealing with a diverse target audience, and is likely to improve the target group-specific communication.Originality/valueThe paper provides an insight into the complexity of city brands and acknowledges that the perception of city brands can differ considerably among different target groups. Additionally, it offers a more comprehensive definition of place brands. This will be helpful for city brand managers and researchers alike in dealing with city brand complexity.

METHOD OF RECOVERY OF PRIORITY VECTOR FOR ALTERNATIVES UNDER UNCERTAINTY OR INCOMPLETE EXPERT ASSESSMENT

Aim. The so-called pair-wise comparison method is one of the most popular decision-making procedures owing to its efficiency, flexibility and simplicity. The primary disadvantage of this method in the context of expert evaluation of large numbers of alternatives or within a sufficiently wide field of knowledge is the impossibility to compare each element with each other, both due to the large number of such comparisons, random gaps and difficulties experienced by the expert while comparing some alternatives. The assessments are affected by gaps that complicate decision-making, as most statistical methods are not applicable to incomplete sets of data. The fairly popular algorithm for processing of pair-wise comparison matrices (the Saaty algorithm) cannot work with matrices that predominantly contain zero components. The purpose of the paper is to develop a method of processing comparison matrices in order to obtain weight coefficients (weights) of the considered alternatives that enable quantitative comparisons. Methods. In practice, there are several approaches to managing sets of data with gaps. The first, most easily implementable, approach involves the elimination of copies with gaps from the set with further handling of only complete data. This approach should be used in case gaps in data are isolated. Although even in this case there is a serious risk of “losing” important trends while deleting data. The second approach involves using special modifications of data processing methods that tolerate gaps in sets of data. And, finally, there are various methods of evaluation of missed element values. Those methods help to fill in the gaps in sets of data based on certain assumptions regarding the values of the missing data. The applicability and efficiency of individual approaches, in principle, depends on the number of gaps in data and reasons of their occurrence. In this paper, the pair-wise comparison matrix is considered in the form of a loaded graph, while the alternatives are the nodes and comparisons are the edges of the graph. Respectively, if a pair of alternatives occurs for which the expert could not specify a preference, the corresponding edge is absent. The paper considers a way of removing edges that correspond to the most controversial values, i.e. a cycle breakage algorithm that causes transformation of the initial graph to the spanning tree that allows for unambiguous comparison of any two alternatives. The algorithm of joint alignment of both the upper and lower boundaries of expert assessments is not considered in this paper. Results. The paper gives an example of practical application of the developed algorithm of processing incomplete matrices of pair-wise comparisons of ten objects obtained in a certain expert assessment. It also shows the efficiency of the suggested approach to priority recovery of compared alternatives, explores ways of automating computing and future lines of research. Conclusions. The proposed method can be used in a wide range of tasks of analysis and quantitative evaluation of risks, safety management of complex systems and objects, as well as tasks related to the verification of compliance with the requirements for such highly dependable elements as nuclear reactors, aviation and rocket technology, gas equipment components, etc., i.e. in cases when low (less than 0,01) probabilities of failure per given operation time are to be evaluated, while the failure statistics for such elements in operation is practically nonexistent. The proposed algorithm can be applied in expert assessment in order to identify the type and parameters of time to failure distribution of such highly dependable elements, which in turn will allow evaluating dependability characteristics with the required accuracy

АНАЛІТИЧНЕ ЗАБЕЗПЕЧЕННЯ СТРАТЕГІЇ РОЗВИТКУ СІЛЬСЬКОГОСПОДАРСЬКОГО ПІДПРИЄМСТВА

Тhis article examines the theoretical essence of the concept of agricultural enterprise management development strategy, namely that the development strategy of agricultural enterprise management is a set of measures aimed at forming new areas of improvement in the agricultural sector of the economy in relation to further actions in the market. The current scientific trends in determining the analytical support and its importance during the operation of the business entity are analyzed. The issues of strategy are considered and the main aspects of ensuring strategic development at domestic enterprises are formed. The key approaches of the complex system of management of strategic development of the agricultural enterprise are established, their general characteristic is carried out. Based on the study, the following approaches are: organizational, economic, technological, informational and innovative, which have a significant impact on the agricultural activities of the enterprise through the formation of competitive decisions by managers, whose main goal is to achieve predetermined goals and objectives of the main system. conditions of management of competitive positions of the agricultural enterprise. The importance of including each type of analysis in the formation of enterprise strategy in order to achieve a high degree of efficiency of the business entity. The external and internal factors that have an impact on the functioning of the management system for the development of the enterprise, as well as the systematization of goals, principles and patterns of management of this development. The structure of the analysis in the context of its types, namely strategic, current and operational, is systematized and detailed.

Kibernetinės grėsmės ir globali verslo aplinka

The paper deals with the issue of cyber threats within the realm of global business environment, approached through the multidisciplinary prism: law (national and international law), politics, economics, philosophy. Article’s structure is divided into 4 parts. Introduction submits facts in order to demonstrate the authenticity of cyber threats and especially their largescale damage suffered by global business entities. Current vulnerabilities of cyber domain are a consequence of its decentralized architecture and shortage of law regulations. In the second part “Hybrid threats” brief notice is given of concept’s essence, its interpretation with due regard to cyber threat as a form of hybrid threat. Specifically, the cyber attacks represent a type of hybrid threats, endangering the performance of states fundamental functions. Launching cyber attacks against critical infrastructure of states could give rise to the invocation of unilateral or collective self-defense, in line with the international law. Current applicability of contemporary international law to the cyber domain substantially diminishes the chances of new legal regime emergence. The third part “Critical national infrastructure and legal framework” focuses on defining the notion of critical national infrastructure and respectively its disposure to cyber threats. Notwithstanding the fact that the notion of “critical national infrastructure” does not enjoy a uniform understanding, it is subject to the states determination by means of adoption national legislation. Adversaries employ a number of sophisticated types of operations in the cyber space which presuppose distinct legal regulation and different resilience mechanisms. Resort to cyber attack, being one the gravest cyber threats, might even trigger the inherent right of states to self-defense. Nowadays the use of force could not be rendered to its classical but yet rather restrictive interpretation, namely referring just to the kinetic means. Cyber attacks exemplify a brand new type of use of force, employed by the adversaries in the international relations. Rapid developments in the field of digital environment substantially leave behind the existing legal regulations. Cyber threats are addressed in terms of cyber security measures undertaken on universal (UN), regional (EU, NATO) and national level. Bolstering cyber security should include artificial intelligence technologies. Deficiency of one fits all approach towards enhancing cyber security requires seeking for the alternatives. Employment of an artificial intelligence within the cyber domain is worth considering among many options. Obvious advantages of artificial intelligence systems are usually followed by a number of risks. Undisputed benefits provided by the utilization of artificial intelligence in the field of cyber security should be assessed though the risks. The latter predominantly relates to the caveat against artificial intelligence transforming into a weapon possessing supernatural features. Promising future of artificial intelligence (managing complex systems combined with multitasking; likewise its opposite application with the aim of compromising other states), however not yet discovered to the full extent, is hard to resist. Hence, paving way for a future arms race between states. Key developments in the area of cyber security will be apparently influenced by the proliferation and subsequent sophistication of artificial intelligence systems. Conclusions outline key findings of the research. Capacities of cyber threats have not been exhaustively disclosed by the adversaries and hence such an obscurity is even more dangerous than ever.

EVALUATION OF FOOD SELF-SUFFICIENCY OF THE REPUBLIC OF TATARSTAN DISTRICTS

The article presents the author's method for estimation of the level of food self-sufficiency for the main types of food products in the regions of Republic of Tatarstan. The proposed method is based on the use of analytical methods and mathematical comparative analysis to compose a final rating. The proposed method can be used in the system of regional management of agro-industrial complex on the federal and local level. Relevance. The relevance of this work is caused by on the one hand a hardening of foreign policy that may negatively impact on national food security, and on the other hand the state crisis of the domestic agricultural sector. All this requires the development of new approaches to regional agribusiness management. Goal. To develop a methodology is used to assess the level of food self-sufficiency. To rate the level of self-sufficiency in main types of foodstuff in regions of Republic of Tatarstan. Materials and Methods. Statistical data of the results of the AIC of the Republic of Tatarstan for 2016 was used for the study. Analytical methods, including mathematical analysis and comparison were used. Results. Based on the analysis of the present situation for ensuring of food security in Russia it was shown that now it is necessary to develop effective indicators identifying the level of self-sufficiency in basic food regions. It was also revealed that there are no such indicators in system of regional agrarian and industrial complex at present time. As a result of analysis existing approaches the author's method of rating the level of self-sufficiency of regions was offered. This method was adopted on the example of the Republic of Tatarstan. Conclusions. The proposed method of rating estimation of self-sufficiency for basic foodstuffs can be used in the regional agroindustrial complex management system at the federal and local level. It can be used to rank areas in terms of their self-sufficiency for basic foodstuffs. This allows focusing on the improvement of backward non-advanced areas in agroindustry and making appropriate management decisions. The final rating value was 0.88 that was obtained from the analysis of the situation in the Republic of Tatarstan showing that the situation in matters of self-sufficiency for basic foodstuffs in general was good. However, there are reserves, as the maximum possible value of the rating may be 1. In the application of the proposed methodology for the assessment of the situation in various regions of the country, now it is possible to compare and evaluate the situation to take appropriate decisions for the development of management.

RATING MODELS AND INFORMATION TECHNOLOGIES APPLICATION FOR MANAGEMENT OF ADMINISTRATIVE-TERRITORIAL COMPLEXES

Purpose. The paper aims to develop rating models and related information technologies designed to resolve the tasks of strategic planning of the administrative and territorial units’ development, as well as the tasks of multi-criteria control of inhomogeneous multiparameter objects operation. Methodology. When solving problems of strategic planning of administrative and territorial development and heterogeneous classes management of objects under control, a set of agreed methods is used. Namely the multi-criteria properties analysis for objects of planning and management, diagnostics of the state parameters, forecasting and management of complex systems of different classes. Their states are estimated by sets of different quality indicators, as well as represented by the individual models of operation process. A new information technology is proposed and created to implement the strategic planning and management tasks. This technology uses the procedures for solving typical tasks, that are implemented in MS SQL Server. Findings. A new approach to develop models of analyze and management of complex systems classes based on the ratings has been proposed. Rating models development for analysis of multicriteria and multiparameter systems has been obtained. The management of these systems is performed on the base of parameters of the current and predicted state by non-uniform distribution of resources. The procedure of sensitivity analysis of the changes in the rating model of inhomogeneous distribution of resources parameters has been developed. The information technology of strategic planning and management of heterogeneous classes of objects based on the rating model has been created. Originality. This article proposes a new approach of the rating indicators’ using as a general model for strategic planning of the development and management of heterogeneous objects that can be characterized by the sets of parameters measured on different scales. At this the control of separate elements is realized by the way of individual mental models construction and application of functioning processes. The procedure for evaluating of the prediction reliability based on multivariate linear extrapolation method was proposed. Practical value. The proposed method of strategic planning of the complex systems’ development based on rating models and developed information technology are representing the complex of automated tools to ensure effective economical and technological control of non-uniform sets of multiparameter objects. The new solutions of typical tasks of strategic planning and development of complex objects management procedure are implemented in the information technology of rating estimation (rating definition, sensitivity analysis, clustering, diagnostics, forecasting, resource allocation, multi-criteria analysis etc.). Application of the proposed information technology can automate the task of analysis and strategic planning of the administrative-territorial complexes. The technology can be used for monitoring, analysis, strategic planning and management of several complex system types simultaneously.

Modelling the Supply of Wood Fuel in Ancient Rome

AbstractProvisioning the city of Rome required complex systems of management and procurement. Despite the importance of wood for baking the grain of theannonaand heating the water for baths (among other applications), there is little evidence for the human or ecological connections that supplied Rome with this crucial fuel. By examining parallel institutions, this article provides a model for explaining how the city of Rome met the energy demands of its massive population. We suggest some ways urban labour was linked to Italian forests, creating a sustainable mode of supply that lasted for centuries.

Immunity-based aircraft actuator failure evaluation

Purpose This paper aims to present the development of prediction models for aircraft actuator failure impact on flight envelope within the artificial immune system (AIS) paradigm. Design/methodology/approach Simplified algorithms are developed for estimating ranges of flight envelope-relevant variables using an AIS in conjunction with the hierarchical multi-self strategy. The AIS is a new computational paradigm mimicking mechanisms of its biological counterpart for health management of complex systems. The hierarchical multi-self strategy consists of building the AIS as a collection of low-dimensional projections replacing the hyperspace of the self to avoid numerical and conceptual issues related to the high dimensionality of the problem. Findings The proposed methodology demonstrates the capability of the AIS to not only detect and identify abnormal conditions (ACs) of the aircraft subsystem but also evaluate their impact and consequences. Research limitations/implications The prediction of altered ranges of relevant variables at post-failure conditions requires failure-specific algorithms to correlate with the characteristics and dimensionality of self-projections. Future investigations are expected to expand the types of subsystems that are affected and the nature of the ACs targeted. Practical implications It is expected that the proposed methodology will facilitate the design of on-board augmentation systems to increase aircraft survivability and improve operation safety. Originality/value The AIS paradigm is extended to AC evaluation as part of an integrated and comprehensive health management process system, also including AC detection, identification and accommodation.

The influence of battery degradation level on the selected traction parameters of a light-duty electric vehicle

The article describes results of an analysis of the impact of degradation level of battery made in lead-acid technology on selected traction parameters of an electric light duty vehicle. Lead-acid batteries are still used in these types of vehicles. They do not require complex systems of performance management and monitoring and are easy to maintaining. Despite the basic disadvantage, which is the low value of energy density, low price is a decisive factor for their use in low-speed electric vehicles. The process of aging of the battery related with an increase in internal resistance of the cells and the loss of electric capacity of the battery was considered. A simplified model of cooperation of the DC electric motor with the battery assuming increased internal resistance was presented. In the paper the results of comparative traction research of the light-duty vehicle equipped with a set of new batteries and set of batteries having a significant degradation level were showed. The analysis of obtained results showed that the correct exploitation of the battery can slow down the processes of degradation and, thus, extend battery life cycle.

Exploring System Space with Graph Theory

AbstractAs today's Cyber Physical Systems (CPS) become more and more complex they provide both incredible opportunity and risk. Model Based Systems Engineering (MBSE) provides organizations a timely opportunity to address the complexities of Cyber Physical Systems. MBSE tools, languages and methods are having a very positive impact but are still in a formative stage and continue to evolve. Moreover, the Systems Modeling Language (SysML) has proven to be a significant enabler to advance MBSE methods given its flexibility and expressiveness. Unfortunately the number of people who know SysML well is relatively small. To bring the full power of MBSE to the larger community, system models can be rendered in intuitive forms to support broad understanding of system models. More specifically, Graph Theory has proven to be very effective in the design, analysis, management, and integration of complex systems. Use of Graph Theory and dynamic visualization can help teams gain insights, build intuition and ultimately help speed the innovation process.

Tinbergen and tipping points: Could some thresholds be policy-induced?

Thresholds and tipping points that are characteristic of dynamic multi-stability are increasingly prominent touchstones of the science-policy interface. Prior economic work has shown thresholds arising in convex-concave ecological models that exclude humans may disappear in models of coupled economic-ecological systems when economic agents are included as part of the system. Less well-understood is how this result may depend on the ability of humans to manage complex systems. We examine the role of institutions that condition the available management choices. We find institutional restrictions do not generate non-convexities when the ecological system is well-behaved, but that these restrictions may generate non-convexities when the ecological system is convex-concave. These results are tied to the concept of path controllability, which is when managers have sufficient controls to guide the system across the state space. Path controllability is the dynamic version of the Tinbergen rule, and generally requires separate controls to manage each possible ecological externality. We link the concepts of ecosystem externalities, thresholds, and path controllability to provide new economic insights into problems with the potential for multi-stability, and we illustrate the importance of institutions for managing convex-concave systems.

Models of Hierarchial Control in Ecological-Economic Systems

In this paper, we describe a model for risk management consisting of two submodels: a submodel for efficiency assessment and a submodel for risk assessment of a system and its concrete definition for hierarchical systems. We suggest statements of problems for the management of complex systems that have a hierarchical structure and function under conditions of intrasystem uncertainty. For models of ecological-economic systems of regional and corporate type, we propose management arrangements that allow reconcile interests of subsystems and thus avoid the decentralization risk.

Impact of technology infusion on system architecture complexity

ABSTRACTIn complex systems with long life cycles, it is expected that the requirements of these systems will change over time. Therefore, it is important to be able to upgrade the system accordingly over time. This is often accomplished by infusing new technologies into the host system in order to update or improve the overall system performance. However, technology infusion often requires a redesign of the host system, resulting in a change in the overall system architecture complexity. In this study, we used the structural complexity index to analyse the impact of technology infusion by performing three main steps: (1) measurement of structural complexity, (2) Comparative Analysis A to determine the impact of components and their interfaces in each system and (3) Comparative Analysis B to determine the impact of technology infusion. To demonstrate the proposed process, we analyse technology infusion concepts for a hydrogen-enhanced combustion engine. Results show that the structural complexity index can be used as an indicator of the impact of design changes. To manage complex systems, decision-makers should consider the impact of technology infusion on the upgraded system, and select a better solution with high benefits and lower costs.

Effects of Data and Model Simplification on the Results of a Wetland Water Resource Management Model

This paper presents the development of a wetland water balance model for use in a large river basin with many different wetlands. The basic model was primarily developed for a single wetland with a complex water management system involving large amounts of specialized input data and water management details. The aim was to simplify the model structure and to use only commonly available data as input for the model, with the least possible loss of accuracy. Results from different variants of the model and data adaptation were tested against results from a detailed model. This shows that using commonly available data and unifying and simplifying the input data is tolerable up to a certain level. The simplification of the model has greater effects on the evaluated water balance components than the data adaptation. Because this simplification was necessary for large-scale use, we suggest that, for reasons of comparability, simpler models should always be applied with uniform data bases for large regions, though these should only be moderately simplified. Further, we recommend using these simplified models only for large-scale comparisons and using more specific, detailed models for investigations on smaller scales.

Complex HIV/AIDS Landscapes: Reflections on How ‘Path Creation’ Influenced an Action-Oriented Intervention

This article reflects on the way in which the path creation theorem influenced an intervention designed to overcome an intractable challenge during a community-university partnership in the Limpopo Province, South Africa. The intractable challenge related to the legacy of the Abstain, Be Faithful, Condomise (ABC) campaign that was mounted in the early 1990s to reduce the global impact of HIV/AIDS. Despite the context of the HIV/AIDS epidemic having shifted significantly since the ABC slogan was invented, the community partner—who focus on HIV/AIDS-related work—reported that the ABC-legacy continued to be a source of frustration in their work. In order to begin the process of overcoming the challenge, the partnership decided to go beyond the conventional boundaries of community-based HIV/AIDS discourses and develop an intervention influenced by complexity. The guiding heuristic for the design was the path creation theorem, placing special emphasis on the initial conditions, contingency, self-reinforcing mechanisms and lock-ins. The findings from the reflection indicate that concepts associated with path creation added value to the design—particularly from the perspective of incorporating processes of emergence over contingent events. The article concludes by suggesting that the path creation theorem was a flexible heuristic and that the application may have opened opportunities to explore the synergies between managing complex systems and more conventional forms of managing community-based interventions relating to HIV/AIDS.

Characterizing Drought in Irrigated Agricultural Systems: The Surface Water Delivery Index (SWDI)

Quantifying surface water shortages in arid and semiarid agricultural regions is challenging because limited water supplies are distributed over long distances based on complex water management systems constrained by legal, economic, and social frameworks that evolve with time. In such regions, the water supply is often derived in a climate dramatically different from where the water is diverted to meet agricultural demand. The existing drought indices which rely on local climate do not portray the complexities of the economic and legal constraints on water delivery. Nor do these indices quantify the shortages that occur in drought. Therefore, this research proposes a methodological approach to define surface water shortages in irrigated agricultural systems using a newly developed index termed the Surface Water Delivery Index (SWDI). The SWDI can be used to uniformly quantify surface water deficits/shortages at the end of the irrigation season. Results from the SWDI clearly illustrate how water shortages in droughts identified by the existing indices (e.g., SPI and PDSI) vary strongly both within and between basins. Some surface water entities are much more prone to water shortages than other entities based both on their source of water supply and water right portfolios.