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This is the pilot study of a larger project in which fortification was evaluated in a clinical intervention trial in the Vaal Triangle of South Africa. The main purpose is to determine the suitability of stock cubes and stock powder as possible vehicles for fortification. A questionnaire was developed to determine stock cube and stock powder consumption patterns and handed out to the 802 subjects in the randomly selected sample, after testing for reliability. The results showed that 97 per cent of respondents (n=802) used stock cubes or powder daily in cooking, mainly stews, with the total consumption being 26 per cent chicken, 24 per cent beef, 15 per cent oxtail, 12 per cent mutton, 12 per cent tomato and 11 per cent vegetable. Stock cubes (79 per cent) were more popular than stock powder (21 per cent). From a consumption point of view, compared with other staple foods such as wheat flour, sugar and maize meal, stock cubes and/or stock powder are consumed on a daily basis by 97 per cent respondents and might thus be suitable vehicles for delivering micronutrients to many population groups without major changes in food production or changes in customary diets.

This paper seeks to develop universal software (a programming framework) enabling the implementation of service robot controllers. The software should distinguish the hardware‐oriented part of the system from the task‐oriented one. Moreover, force, vision as well as other sensors should be taken into account. Multi‐effector systems have to be considered.

The robot programming framework MRROC++ has been implemented as a hierarchical structure composed of processes, potentially consisting of threads. All of the software is written in an object‐oriented manner using C++ and is supervised by a QNX real‐time operating system. The framework has been verified on several systems executing diverse tasks. Here, a Rubik's cube puzzle‐solving system, consisting of two arms and utilizing force control and visual servos, is presented.

The presented framework is well suited to tasks requiring two‐handed manipulation with force sensing, visual servoing and online construction of plans of actions. The Rubik's cube puzzle is a reasonable initial benchmark for validation of fundamental service robot capabilities. It requires force sensing and sight coupled with two‐handed manipulation and logical reasoning, as do the majority of service tasks. Owing to the use of force sensing during manipulation, jamming of the faces has always been avoided; however, visual servoing could only cope with slow handing over of the cube due to the volume of computations associated with vision processing.

The proposed software structure does not limit the implementation of service robot controllers. However, some of the specific algorithms used for the solution of the benchmark task (i.e. Rubik's cube puzzle) need to be less time‐consuming.

The MRROC++ robot programming framework can be applied to the implementation of diverse robot controllers executing complex service tasks.

A demanding benchmark task for service robots has been formulated. This task, as well as many others, has been used to validate the MRROC++ robot programming framework which significantly facilitates the implementation of diverse robot systems.

The spatial feature is important for scene saliency detection. Scene-based visual saliency detection methods fail to incorporate 3D scene spatial aspects. This paper aims to propose a cube-based method to improve saliency detection through integrating visual and spatial features in 3D scenes.

In the presented approach, a multiscale cube pyramid is used to organize the 3D image scene and mesh model. Each 3D cube in this pyramid represents a space unit similar to a pixel in the image saliency model multiscale image pyramid. In each 3D cube color, intensity and orientation features are extracted from the image and a quantitative concave–convex descriptor is extracted from the 3D space. A Gaussian filter is then used on this pyramid of cubes with an extended center-surround difference introduced to compute the cube-based 3D scene saliency.

The precision-recall rate and receiver operating characteristic curve is used to evaluate the method and other state-of-art methods. The results show that the method used is better than traditional image-based methods, especially for 3D scenes.

This paper presents a method that improves the image-based visual saliency model.

The purpose of this study is to focus on the issue of paradigms in human resource development (HRD) and validate the HRD cube as a synthesized model of HRD praxis and to explicate some of the extant paradigms of HRD.

The study was carried out by examining the text of articles published in Academy of Human Resource Development (AHRD)-sponsored journals over a specific period. Sixteen articles published in AHRD-sponsored journals were treated as if they were the representative voice(s) of their author(s). Data units were axially coded and sorted into one of seven pre-determined categories based on the axioms of theory, research and practice. Then, data units were open coded using the constant comparative method, and themes were developed.

Axial coding results identified a dominant emphasis on practice. The accumulation of units representing research and theory were comparatively smaller. Evidence of shared perspectives was found that emphasized the practice axiom. Open coding results identified representative themes within each of the axiom-based categories of theory, research and practice. Six themes developed in the theory category, nine themes developed in the research category and six themes developed in the practice category.

The results support the overall construction of the HRD cube. Given the initial validation and support of the HRD cube and of the components described within the theory, research and practice sides within these 16 articles published in AHRD-sponsored journals, at least 18 prospective paradigms of HRD were identified.

The cementitious/chemical properties of the untreated CFA are dependent on the coal composition and previous burning conditions. The purpose of this paper is to investigate whether untreated CFA can efficiently reduce cement replacement and does not require further combustion treatment to be a viable cement replacement.

Two types of mixes: Type I concrete and PCFA (Type I and 30 per cent untreated CFA) concrete were batched and subjected to compressive strength tests and cyclic exposures of 5 per cent sodium sulphate (Na₂SO₄) and 5 per cent magnesium sulphate (MgSO₄), respectively.

PCFA mix was 41.1 and 35.21 per cent lower in strength compared to Type I at 28 and 56 days correspondingly. Continuous-sulphate-exposure resulted in slow but continued strength development for both mixes. However, the strengths of PCFA cubes exposed to cyclic sulphate and sulphate/magnesium salts continued to increase at a lower rate from their corresponding 28-day strength (rate of 18.7 per cent and strength 27.30 MPa in Na₂SO₄ and rate of 10.0 per cent and strength 25.30 MPa in MgSO₄) while Type I specimens subjected to the same exposure conditions experienced drastic reductions in strength (rate of −15.0 per cent and strength 33.21 MPa in Na₂SO₄ and rate of −23.4 per cent and strength 29.94 MPa in MgSO₄).

Results justify the need for additional tests essentially: at different percentage replacement of untreated CFA, fineness of materials, chloride environment and longer exposures, to address the cementitious properties of untreated CFA as cement replacement.

Treatment methods for fly ashes require undoubtedly additional resources, energy input and cost. This paper paves the way to define whether untreated CFA can be used as cement replacement in concrete.

The combined finite‐discrete element method has been used to simulate the gravitational depositions of packs containing particles of cubical shape. This approach to the generation of particle packs is based on the simulation of the dynamics of pack formation including interaction among individual particles, inertia and gravitational forces. The results of such an approach are compared to the experimental results to evaluate both feasibility and accuracy of the combined finite‐discrete element simulation of packing problems.

If the fast multipole method (FMM) is applied in the context of the boundary element method, the efficiency and accuracy of the FMM is significantly influenced by the used hierarchical grouping scheme. Hence, in this paper, a new approach to the grouping scheme is presented to solve numerical examples with problem‐oriented meshes and higher order elements accurately and efficiently. Furthermore, with the proposed meshing strategies the efficiency of the FMM can be additionally controlled.

This paper aims to verify a new method for accurate part manufacturing using a 3D printer. In particular, the direction and position dependence of the printed results are to be verified within the building area. The results of the accomplished experiments are to be used for the computation of new printer adjustments.

Test cubes with a defined edge length were printed and measured afterwards. The test cubes were distributed thereby either over the entire building area or only for a small part of the building area. Next, the test cubes were measured and the differences between measured and desired values were used for adjustment of the printer parameter settings. Therefore, the “bleed compensation” settings were used.

The deviations depended strongly on the position in the building area of the printer. In dependence of the position and orientation, different deviations in the three dimensions of the printer coordinate system resulted. By a calibration of the printer parameters for a reduced part of the processed area, the print accuracy could be strongly increased. Afterward, the calibration the deviations could be reduced from 0.4 mm ±0.2 mm to under 0.04 mm ±0.03 mm.

The work shows the position and direction dependency of the 3D‐printer manufacturing accuracy. Furthermore, a calibration procedure for bleed compensation calibration is presented.

Several chaotic system-based encryption techniques have been presented in recent years to protect digital images using cryptography. The challenges of key distribution and administration make symmetric encryption difficult. The purpose of this paper is to address these concerns, the novel hybrid partial differential elliptical Rubik’s cube algorithm is developed in this study as an asymmetric image encryption approach. This novel algorithm generates a random weighted matrix, and uses the masking method on image pixels with Rubik’s cube principle. Security analysis has been conducted, it enhances and increases the reliability of the proposed algorithm against a variety of attacks including statistical and differential attacks.

In this light, a differential elliptical model is designed with two phases for image encryption and decryption. A modified image is achieved by rotating and mixing intensities of rows and columns with a masking matrix derived from the key generation technique using a unique approach based on the elliptic curve and Rubik’s cube principle.

To evaluate the security level, the proposed algorithm is tested with statistical and differential attacks on a different set of test images with peak signal-to-noise ratio, unified average changed intensity and number of pixel change rate performance metrics. These results proved that the proposed image encryption method is completely reliable and enhances image security during transmission.

The elliptic curve–based encryption is hard to break by hackers and adding a Rubik’s cube principle makes it even more complex and nearly impossible to decode. The proposed method provides reduced key size.

Results are given which establish a computational foundation for simplicial approximation and design centering of a convex body. A simplicial polyhedron is used to approximate the convex body and the “design center”, i.e. the point inside the body furthest in some norm from its exterior, is approximated by the point in the polyhedron furthest from its exterior. A point representation of the polyhedron is used, so that there is no necessity for computing or storing the faces of the approximation. Since in N space there can be factorially more faces than points, we are able to achieve significant efficiencies in both operation count and storage requirements, compared to previously reported methods. We give results for the 2 norm and the max norm, and demonstrate that our new method is operable in the nonconvex case, and can handle a mixed basis of faces and points as well.