Systemic Thinking and Practice Toward Facilitating Inclusive Education: Reflections on a Case of Co-Generated Knowledge and Action in South Africa

This article offers our reflections around a case of facilitating systemic thinking and practice in which the first author of the article (Tlale) interacted with research participants/participant researchers with the intention of strengthening systemic thought and action toward fostering inclusive education in the setting (a rural school in the Eastern Cape in South Africa). We reflect upon the process and also how our engagement was perceived by participants, as expressed in feedback received from them. We point to how Tlale introduced the idea of systemic thinking (to teachers, school management team, school governing body, and a district officer for the district) as tied to the possibility of acting to generate transformation toward a more inclusive educational context for the benefit of the learners at the school in question, thus acting as a systemic mediator on their behalf.     

The Ordering and Replacement Policy for the System with Two Types of Failures

In this paper, the optimal maintenance policy is investigated for a system with stochastic lead time and two types of failures. The system has two types of failures, one type is repairable, when the repairable failure occurs, the system will be repaired by repairman, and the system after repair is not "as good as new". The other type of failure is unrepairable, and when the unrepairable failure occurs the system must be replaced by a new and identical one. The spare system for replacement is available only by order, and the lead time for delivering the spare system is stochastic. The successive survival times of the system form a stochastically decreasing geometric process, the consecutive repair times after failures of the system form a renewal process. By using the renewal process theory and geometric process theory, the explicit expression of the long-run average cost per unit time under ordering policy(N-1) is derived, and the corresponding optimal can be found analytically. Finally,the numerical analyses are given.     

Effect of MWCNT reinforcement on the precipitation-hardening behavior of AA2219

Aluminum alloy matrix composites have found a predominant place in research, and their applications are explored in almost all industries. The aerospace industry has been using precipitation-hardenable alloys in structural applications. However, insufficient literature is available on the influence of multiwalled carbon nanotubes (MWCNTs) on precipitation-hardenable alloy composite materials; thus, this work was designed to elucidate the effect on MWCNT reinforcement on AA2219 with and without precipitation hardening. Reinforcement with MWCNTs has been reported to accelerate precipitation and to achieve greater hardness within a much shorter time. The addition of 0.75wt% MWCNTs resulted in maximal hardness at 90 min, which is approximately 27% of improvement over the maximum hardness achieved by the corresponding monolithic alloy after 10 h of aging. The sample reinforced with 0.75wt% MWCNTs showed an improvement of 82% in hardness by solutionizing and aging compared to that achieved by sintering.     

A novel GEL-OHA/HAp bone substitute

Self-crosslinked gelatin-oxidized hyaluronic acid/ hydroxyapatite (GEL-OHA/HAp) composite bone substitute was successfully prepared with a novel in situ precipitation method without using any toxic chemical cross-linkers, and its characterizations, including elemental composition, surface morphology, crystallinity, and structure of crystalline phase, were carried out. In order to evaluate its corresponding performances, comparisons with glutaraldehyde crosslinked gelatin/hydroxyapatite (GEL-Glu/ HAp) composite were made in detail. The results indicate that nano-HAp crystallites are homogeneously dispersed in both GEL-OHA/HAp and GEL-Glu/HAp composites, and the HAp crystallites in the former take larger particle size than those in the latter. Mechanical property tests show the acceptable mechanical strength at high strain of GEL-OHA/HAp composite. Study of in vitro degradation and swelling demonstrate that the two composites have similar degradation rate and water absorption capability. By in vitro cell culture, it has been found out that the cells on the GEL-OHA/HAp composite show higher proliferative potential than the cells on the GEL-Glu/HAp composite. Compared with GEL-Glu/HAp composite, GEL-OHA/HAp composite provides an excellent strategy for preparation of non-toxic bone substitute with acceptable corresponding properties.     

Generalized inverse eigenvalue problem for (<Emphasis Type="Italic">P</Emphasis>,<Emphasis Type="Italic">Q</Emphasis>)-conjugate matrices and the associated approximation problem

In this paper, the generalized inverse eigenvalue problem for the (P,Q)-conjugate matrices and the associated approximation problem are discussed by using generalized singular value decomposition (GSVD). Moreover, the least residual problem of the above generalized inverse eigenvalue problem is studied by using the canonical correlation decomposition (CCD). The solutions to these problems are derived. Some numerical examples are given to illustrate the main results.     

A star-style trust model with the ability of data recovery for trusted computing platform

Varieties of trusted computing products usually follow the mechanism of liner-style chain of trust according to the specifications of TCG. The distinct advantage is that the compatibility with the existing computing platform is preferable, while the shortcomings are obvious simultaneously. A new star-style trust model with the ability of data recovery is proposed in this paper. The model can enhance the hardware-based root of trust in platform measurement, reduce the loss of trust during transfer process, extend the border of trust flexibly, and have the ability of data backup and recovery. The security and reliability of system is much more improved. It is proved that the star-style trust model is much better than the liner-style trust model in trust transfer and boundary extending etc. using formal methods in this paper. We illuminate the design and implementation of a kind of trusted PDA acting on star-style trust model.     

Attribute level lineage in uncertain data with dependencies

In uncertain data management, lineages are often used for probability computation of result tuples. However, most of existing works focus on tuple level lineage, which results in imprecise data derivation. Besides, correlations among attributes cannot be captured. In this paper, for base tuples with multiple uncertain attributes, we define attribute level annotation to annotate each attribute. Utilizing these annotations to generate lineages of result tuples can realize more precise derivation. Simultaneously, they can be used for dependency graph construction. Utilizing dependency graph, we can represent not only constraints on schemas but also correlations among attributes. Combining the dependency graph and attribute level lineage, we can correctly compute probabilities of result tuples and precisely derivate data. In experiments, comparing lineage on tuple level and attribute level, it shows that our method has advantages on derivation precision and storage cost.     

An anonymous authentication scheme withstanding the conspiracy attack

A novel anonymous authentication scheme is proposed based on the ring signature. In the scheme, the private key and the the freely chosen anonymity set are used to achieve anonymous authentication. In terms of the threshold sharing, a group of t members jointly implement threshold tracking. In order to improve the security of tracking, message recovery equation is used to verify and recover data leaked by the user. Compared with Liu et al’s scheme, the proposed scheme can resist conspiracy tracking and has less computational cost. On the premise of the discrete-logarithm-based assumption put forth by Lysyanskaya, Rivest, Sahai, and Wolf (LRSW) and Diffie-Hellman (DDH) assumption, the scheme is proved to meet the demands of anonymous authentication. The scheme has broad application prospects in many fields such as ad hoc network, electronic voting, and so on.     

A model-based calibration method of automotive electronic control unit

This paper presents a systematic method of designing the calibration toolbox of automotive electronic control unit (ECU) based on real-time workshop (RTW). To break the strong coupling of each functional layer, the hierarchical architecture of the calibration system is divided into the bottom driver layer, the intermediate interface layer and the top application layer. The driver functions meeting the specification of the automotive open system are sent and received in the intermediate interface layer. To reduce the development costs, the portable user codes are generated by RTW which provides a development environment from system simulation to hardware implementation. Specifically, the calibration codes yielded from the controller area network (CAN) calibration protocol (CCP) module are integrated into the control codes, called by a compiler in the daemons to build a corresponding project, and then downloaded into the object board to provide the A2L file. The experiments illustrate that the different drive modules are only needed to be replaced for the implementation of the calibration system applied in different hardware platforms.