A review on 3D printing functional brain model

Modern neuroscience increasingly relies on 3D models to study neural circuitry, nerve regeneration, and neural disease. Several different biofabrication approaches have been explored to create 3D neural tissue model structures. Among them, 3D bioprinting has shown to have great potential to emerge as a high-throughput/high precision biofabrication strategy that can address the growing need for 3D neural models. Here, we have reviewed the design principles for neural tissue engineering. The main challenge to adapt printing technologies for biofabrication of neural tissue models is the development of neural bioink, i.e., a biomaterial with printability and gelation properties and also suitable for neural tissue culture. This review shines light on a vast range of biomaterials as well as the fundamentals of 3D neural tissue printing. Also, advances in 3D bioprinting technologies are reviewed especially for bioprinted neural models. Finally, the techniques used to evaluate the fabricated 2D and 3D neural models are discussed and compared in terms of feasibility and functionality.     

The development of a highly interactive searching technique for morphs—Minicomputer operated retrieval (partially heuristic) system

The basic structure of MORPHS was described at the Fifth Cranfield Conference when emphasis was placed on the automatic root finding/role applying procedures based on linguistic principles. This skeleton remains, but it has since been clothed with relatively complex, iterative search strategies. The major strategy employs the normal Boolean operators either in the form of strings without bracketing or in the form of marked steps. The latter enables back-tracking to be carried out. Recycling of search strategies is only limited by the number of tracks available for storing searches on the disc unit before over-writing takes place. Printing-out does not interfere with searching. A second strategy treats a string of keywords as a compound word; if it fails to find it the compound is then decomposed into its elements, which are then automatically treated as a string connected by AND logic; incidentally this technique also acts as a bracketing technique, but without the inconvenience of physical brackets. SDI procedures have been evolved as a by-product.Ultimately it is hoped that it may be possible to develop a degree of question answering ability: this could be achieved in several ways. The simplest (based on the modifying effect of certain interrogatory elements, e.g. WHO) has been evaluated and works. With the exception of the SDI system which employs 16k, all of the above systems were developed and originally operated in 12k of core with 16 bit words on a minicomputer. Nevertheless, despite this severe restriction on space it has been possible to implement searching strategies for dedicated on-line searching which are at least as good and in many ways better (e.g. automatic synonym substitution) than many employed in the large time-sharing systems currently available.     

Smart city model based on systems theory

While there are several partial solutions to model some aspects of cities (e.g. transportation or energy), there is no framework allowing modelling of a complex system such as a city. This paper aims on providing a solution that can be used by practitioners to model impact of different scenarios and smart city projects encapsulating different subsystems, such as transportation, energetics or, for example, eGovernment. The term “smart cities” is classified into Systems Theory, particularly focusing on Cyber-Physical Systems. This classification is further elaborated to define a new term, so-called Smart City Agent (SCA). The SCA is considered as the main building block for modelling smart cities. The approach within this paper however stresses the interconnection of different systems within a city. Its’ strength is in better exchange of data and among heterogeneous agents. This information management approach is the missing key in the growing market of partial smart city solutions as it will allow simulation of solutions in complex systems such as a city. The suitability of usefulness of the proposed approach is demonstrated on a use case dealing with charging of electrical vehicles. The results show that the approach is suitable for modelling of dynamic behaviour.     

The application of workflow management to digital heritage resources

Recent years have witnessed a noticeable proliferation in Digital Library Systems (DLSs) and their specialized form represented in Digital Heritage Resources (DHRs). DHRs usually manage a complex and varied mix of digital heritage objects of different types and formats. They tend to be complex in nature and usually involve complex, simultaneous and intersecting workflows. As a result, DHRs impose implementation challenges on any solutions that aim to manage their workflows. Thus, despite the proliferation of DHRs, it is a noteworthy trend that there is a general lack of workflow management solutions that can be utilized in such systems. As a research area that is rarely covered, this paper therefore presents the design and development of a novel Workflow Management System (WfMS) built to integrate with DHRs specifically, and DLSs in general. In this context, an experimental WfMS aimed to test the validity of workflow management integration with DHRs. The devised WfMS was built as a workflow management solution that can adequately address the specific hurdles imposed by DHR implementations. Additionally, a novel DHR implementation framework called DISPLAYS (Digital Library Services for Playing with Antiquity and Shared Heritage) is presented as a test bed for the proposed WfMS.     

Event-triggered fully distributed asymptotic consensus for leaderless multiple Euler-Lagrange systems

In this paper, the fully distributed consensus for a class of multiple Euler-Lagrange systems is investigated, where the protocol is designed under the event-triggered control framework and the dynamics of Euler-Lagrange systems are heterogeneous. Since only local information interactions at triggered instants can be used and the Euler-Lagrange systems are of relatively complex dynamics, it is challenging to achieve asymptotic consensus without using any global information (such as the Laplacian matrix information). By skillfully integrating the adaptive control, distributed control and event-triggered control techniques, a novel protocol is proposed for the investigated multiple Euler-Lagrange systems. It is proven that the asymptotic consensus can be achieved by the developed protocol. By a numerical example, the effectiveness of the developed protocol is illustrated.     

Adaptive anti-lag synchronization of two identical or non-identical hyperchaotic complex nonlinear systems with uncertain parameters

In this paper we present the adaptive anti-lag synchronization (ALS) of two identical or non-identical hyperchaotic complex nonlinear systems with uncertain parameters. The concept of ALS is not detected yet in the literature. Based on the Lyapunov function a scheme is designed to achieve ALS of hyperchaotic attractors of these systems. The ALS of two identical complex Lü systems and two different hyperchaotic complex Lorenz and Lü systems are taken as two examples to verify the feasibility of the presented scheme. These hyperchaotic complex systems appear in several applications in physics, engineering and other applied sciences. Numerical simulations are calculated to demonstrate the effectiveness of the proposed synchronization scheme and verify the theoretical results.     

基于成熟度模型的复杂产品系统创新能力评价研究

随着科学技术的迅猛发展,产品系统的复杂程度日益提高,复杂产品系统在提升国民经济总量、促进产业发展、开展技术创新等方面的作用日益增强.针对复杂产品系统的特点,以成熟度模型为重要参考,从技术与管理2个维度构建复杂产品系统创新能力评价指标体系,并采用模糊综合评价法对某复杂产品系统制造企业S公司的创新能力进行案例研究.     

港口陆路集疏运系统的演化机理——基于基础设施投资政策

基于复杂系统演化理论,分析港口陆路集疏运系统在基础设施投资政策下的演化机理和政策效果。将基础设施投资政策视为系统的他组织作用,建立系统的演化模型,通过分析系统在政策他组织作用下能否演化至有序状态来判断政策的有效性。以曹妃甸港集疏运系统为例,结果表明:投资公路基础设施不能促使系统向有序状态演化;应首先投资铁路基础设施,以提高铁路运输的竞争力、构建铁路运输与公路运输间合理的竞合关系,有助于促使系统向有序状态演化;码头泊位设施的投资也应在铁路基础设施投资的基础上实施。     

Nonlinear process monitoring based on generic reconstruction-based auto-associative neural network

A significant concern with statistical fault diagnosis is the large number of false alarms caused by the smearing effect. Although the reconstruction-based approach effectively solves this problem, most of them only focus on linear rather than nonlinear systems. In the present work, a generic reconstruction-based auto-associative neural network (GRBAANN) is proposed that uses the reconstruction-based approach to isolate simple and complex faults for nonlinear systems. Nevertheless, in GRBAANN, it is challenging to acquire a trivial solution for the reconstruction-based index, which is equivalent to a complex vector fixed-point problem. In this regard, the Steffensen method is employed to deal with this problem with an accelerated iterative process, which is appropriate for both single and multiple variable faults. The variable selection procedure is time-consuming but imperative for reconstruction-based approaches, with no exception to the proposed method. In order to ensure the real-time diagnosis for large-scale systems, the Sequential floating forward selection method with memory is proposed to minimize the computation time of the variable selection procedure. The effectiveness of the proposed GRBAANN scheme is illustrated through a validation example and an industrial example. Comparisons with the state-of-art methods are also presented.     

Performance-based university research funding systems

The university research environment has been undergoing profound change in recent decades and performance-based research funding systems (PRFSs) are one of the many novelties introduced. This paper seeks to find general lessons in the accumulated experience with PRFSs that can serve to enrich our understanding of how research policy and innovation systems are evolving. The paper also links the PRFS experience with the public management literature, particularly new public management, and understanding of public sector performance evaluation systems. PRFSs were found to be complex, dynamic systems, balancing peer review and metrics, accommodating differences between fields, and involving lengthy consultation with the academic community and transparency in data and results. Although the importance of PRFSs seems based on their distribution of universities’ research funding, this is something of an illusion, and the literature agrees that it is the competition for prestige created by a PRSF that creates powerful incentives within university systems. The literature suggests that under the right circumstances a PRFS will enhance control by professional elites. PRFSs since they aim for excellence, may compromise other important values such as equity or diversity. They will not serve the goal of enhancing the economic relevance of research.     

Practical non-monotonic knowledge-base system for un-regimented domains: A Case-study in digital humanities

Information systems for un-regimented domains such as museums, art and book collections, face representational and usability challenges that surpass the demands of traditional information systems for regimented domains. While the former require complex conceptual models supporting a set of dynamic and evolving qualitative properties of a small number of objects, the latter focus on the quantitative aspects of a possibly very large number of objects but with a relatively small and stable set of properties. In this paper we study the use of a non-monotonic knowledge-base system for the development of information systems for un-regimented domains. We discuss the ontological assumptions of the formalism, its structure and its inferential mechanisms through a simple example. Then we present an information system for a highly un-regimented domain in the digital humanities with promising results. The present study shows that the so-called extensible, flexible, dynamic or evolving information systems need the expressive power of non-monotonic knowledge-base systems, and that such phenomena should be addressed explicitly.     

Robust stability testing function for a complex interval family of fractional-order polynomials

The robust stability of a family of interval fractional-order systems with complex coefficients is investigated in this study. The concept of “a family of interval fractional-order systems with complex coefficients” means that the characteristic function of a control system can be of both commensurate and non-commensurate orders, the coefficients of the characteristic function can be uncertain parameters, and may be complex numbers. At first, a simple graphical procedure is presented for robust stability analysis. The “robust stability testing function” is then extended to look at the robust conditions. To the best of the authors’ knowledge, no auxiliary function for analyzing the robust stability of the systems under investigation has been introduced until now. Moreover, lower and upper frequency bounds are provided which are useful to improve the computational efficiency of testing the robust stability conditions. Eventually, to verify the results, analytical examples and numerical simulations are provided.     

Embryonic stem cell bioprinting for uniform and controlled size embryoid body formation

Embryonic stem cells (ESCs) are pluripotent with multilineage potential to differentiate into virtually all cell types in the organism and thus hold a great promise for cell therapy and regenerative medicine. In vitro differentiation of ESCs starts with a phase known as embryoid body (EB) formation. EB mimics the early stages of embryogenesis and plays an essential role in ESC differentiation in vitro. EB uniformity and size are critical parameters that directly influence the phenotype expression of ESCs. Various methods have been developed to form EBs, which involve natural aggregation of cells. However, challenges persist to form EBs with controlled size, shape, and uniformity in a reproducible manner. The current hanging-drop methods are labor intensive and time consuming. In this study, we report an approach to form controllable, uniform-sized EBs by integrating bioprinting technologies with the existing hanging-drop method. The approach presented here is simple, robust, and rapid. We present significantly enhanced EB size uniformity compared to the conventional manual hanging-drop method.     

The characteristics and self-time-delay synchronization of two-time-delay complex Lorenz system

Time-delay is frequently encountered in a variety of practical chaotic systems, such as chaos-communication. The behaviours of time-delay chaotic system are greatly different from those of the original system. Self-time-delay synchronization (STDS) implies that the synchronization between the time-delay system and the original system while maintaining the structure and parameters of systems unchanged, thus these various problems produced by time-delay in practice are avoided. Firstly, we investigate the characteristics of two-time-delay complex Lorenz system. Then we take one-time-delay and two-time-delay complex Lorenz system as examples, and design their controllers to realize STDS. One-time-delay complex Lorenz system is a special case of two-time-delay. Numerical simulations verify the validity of the STDS controllers. The controllers only involve error, and it is easy to realize in practice. Moreover, the time-delay chaotic system exhibits highly stochastic behaviors and unpredictable properties, which can be applied to chaos-communication and enhance the security of communication.     

复杂系统、知识管理与组织学习过程动态模型研究

知识经济时代的组织是一个具有无尺度网络结构的复杂系统。知识管理是知识经济时代的必然要求。组织学习作为组织获取核心竞争力和可持续发展能力的重要手段，是一个动态的过程。本文在系统回顾相关研究成果的基础上，从复杂系统的视角对知识经济时代复杂环境下的组织学习动态复杂过程进行了系统的模型整合和创新，并对构建学习型组织可能遇到的障碍进行了一系列对策分析。     

Harvesting random embedding for high-frequency change-point detection in temporal complex systems

Recent investigations have revealed that dynamics of complex networks and systems are crucially dependent on the temporal structures. Accurate detection of the time instant at which a system changes its internal structures has become a tremendously significant mission, beneficial to fully understanding the underlying mechanisms of evolving systems, and adequately modeling and predicting the dynamics of the systems as well. In real-world applications, due to a lack of prior knowledge on the explicit equations of evolving systems, an open challenge is how to develop a practical and model-free method to achieve the mission based merely on the time-series data recorded from real-world systems. Here, we develop such a model-free approach, named temporal change-point detection (TCD), and integrate both dynamical and statistical methods to address this important challenge in a novel way. The proposed TCD approach, basing on exploitation of spatial information of the observed time series of high dimensions, is able not only to detect the separate change points of the concerned systems without knowing, a priori, any information of the equations of the systems, but also to harvest all the change points emergent in a relatively high-frequency manner, which cannot be directly achieved by using the existing methods and techniques. Practical effectiveness is comprehensively demonstrated using the data from the representative complex dynamics and real-world systems from biology to geology and even to social science.     

Hybrid modified function projective synchronization of two different dimensional complex nonlinear systems with parameters identification

In this article, a novel synchronization scheme is proposed to achieve hybrid modified function projective synchronization (HMFPS) in two different dimensional complex nonlinear systems with fully unknown parameters. In the complex space, the response system are asymptotically synchronized up to the different order’s drive system by the state transformation with a scaling function matrix, and all of unknown parameters in both drive and response systems are achieved to be identified. Based on the Lyapunov stability theory, an adaptive controller and updated laws of parameters are developed. Respectively on the ways of increased order and reduced order, the corresponding numerical simulations demonstrate the effectiveness and feasibility of the proposed scheme.     

复杂产品技术能力成长的路径依赖--以我国通信设备制造业为例

复杂产品系统的创新是由自组织网络完成的，其技术能力成长的道路具有路径依赖的特征。本文通过对我国通信设备制造业技术能力成长过程的回顾，阐明了不同技术来源的企业技术能力成长的路径依赖现象，指出正是由于这种路径依赖造成了目前合资企业与国内企业在技术能力上的差异。在快速变化的市场环境下。这种路径依赖造成的技术能力差异也给后来企业赢得竞争优势创造了有利机会。     

A microfluidic co-culture system to monitor tumor-stromal interactions on a chip

The living cells are arranged in a complex natural environment wherein they interact with extracellular matrix and other neighboring cells. Cell-cell interactions, especially those between distinct phenotypes, have attracted particular interest due to the significant physiological relevance they can reveal for both fundamental and applied biomedical research. To study cell-cell interactions, it is necessary to develop co-culture systems, where different cell types can be cultured within the same confined space. Although the current advancement in lab-on-a-chip technology has allowed the creation of in vitro models to mimic the complexity of in vivo environment, it is still rather challenging to create such co-culture systems for easy control of different colonies of cells. In this paper, we have demonstrated a straightforward method for the development of an on-chip co-culture system. It involves a series of steps to selectively change the surface property for discriminative cell seeding and to induce cellular interaction in a co-culture region. Bone marrow stromal cells (HS5) and a liver tumor cell line (HuH7) have been used to demonstrate this co-culture model. The cell migration and cellular interaction have been analyzed using microscopy and biochemical assays. This co-culture system could be used as a disease model to obtain biological insight of pathological progression, as well as a tool to evaluate the efficacy of different drugs for pharmaceutical studies.     

Automatic acquisition of inflectional lexica for morphological normalisation

Due to natural language morphology, words can take on various morphological forms. Morphological normalisation – often used in information retrieval and text mining systems – conflates morphological variants of a word to a single representative form. In this paper, we describe an approach to lexicon-based inflectional normalisation. This approach is in between stemming and lemmatisation, and is suitable for morphological normalisation of inflectionally complex languages. To eliminate the immense effort required to compile the lexicon by hand, we focus on the problem of acquiring automatically an inflectional morphological lexicon from raw corpora. We propose a convenient and highly expressive morphology representation formalism on which the acquisition procedure is based. Our approach is applied to the morphologically complex Croatian language, but it should be equally applicable to other languages of similar morphological complexity. Experimental results show that our approach can be used to acquire a lexicon whose linguistic quality allows for rather good normalisation performance.