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The purpose of this paper is to propose a lossy/lossless binary textual image compression method based on an improved pattern matching (PM) technique.

In the Farsi/Arabic script, contrary to the printed Latin script, letters usually attach together and produce various patterns. Hence, some patterns are fully or partially subsets of some others. Two new ideas are proposed here. First, the number of library prototypes is reduced by detecting and then removing the fully or partially similar prototypes. Second, a new effective pattern encoding scheme is proposed for all types of patterns including text and graphics. The new encoding scheme has two operation modes of chain coding and soft PM, depending on the ratio of the pattern area to its chain code effective length. In order to encode the number sequences, the authors have modified the multi‐symbol QM‐coder. The proposed method has three levels for the lossy compression. Each level, in its turn, further increases the compression ratio. The first level includes applying some processing in the chain code domain such as omission of small patterns and holes, omission of inner holes of characters, and smoothing the boundaries of the patterns. The second level includes the selective pixel reversal technique, and the third level includes using the proposed method of prioritizing the residual patterns for encoding, with respect to their degree of compactness.

Experimental results show that the compression performance of the proposed method is considerably better than that of the best existing binary textual image compression methods as high as 1.6‐3 times in the lossy case and 1.3‐2.4 times in the lossless case at 300 dpi. The maximum compression ratios are achieved for Farsi and Arabic textual images.

Only the binary printed typeset textual images are considered.

The proposed method has a high‐compression ratio for archiving and storage applications.

To the authors' best knowledge, the existing textual image compression methods or standards have not so far exploited the property of full or partial similarity of prototypes for increasing the compression ratio for any scripts. Also, the idea of combining the boundary description methods with the run‐length and arithmetic coding techniques has not so far been used.

This paper presents an efficient lossless compression method to reduce the storage requirement and transmission time for radiographic non‐destructive testing images of aircraft components. The method is based on a combination of predictive coding and the integer wavelet transform. By using the component CAD model to divide the radiographic image of aircraft components into different regions with each region having the same material structure, the parameters of the predictors and the choice of the integer wavelet transform are optimised according to the specific image features contained in each region. Using a real radiographic image of a practical aircraft component as an example, the proposed method is presented and shown to offer a significantly higher compression ratio than other lossless compression schemes currently available.

The purpose of this paper is to introduce PDF/A to replace TIFF as the preferred file format for digitization of textual documents. In addition, PDF/A can be used as an open archival information system (OAIS) submission information package (SIP) container to reduce digitization and digital preservation costs.

The author first reviewed the current digitization guidelines, the OAIS model and provides on an overview of the development PDF and PDF/A as international standards. Then literature review of the uses of PDF/A is presented. The author analyzed pitfalls of TIFFs as the preferred format for digitization, and showed how to use PDF/A to code digitization SIP.

TIFF file format has been the preferred master file format by Federal Agency Digitization Guidelines Initiative digitization guidelines for the past 20 years. However, there are drawbacks of TIFF format. Literature reviews show that PDF/A has been the preferred standard for coding born-digital documents in court, government and business sectors. PDF/A-2 and PDF/A-3 are relatively new standards released after 2010. However, few understood the standards and have utilized the full potentials in digitization. The author shows that PDF/A can be used as an OAIS SIP container.

In order to delivery OAIS SIPs, current practices require a combination of files, directories and various types of metadata. The author shows that PDF/A (PDF/A-2 and/or PDF/A-3) can be a better file format for textual document digitization with coding various types of metadata in extensible metadata platform and arbitrary file/data can be coded in PDF/A-3. These features in PDF/A provide much better ways to deliver SIPs in a cost-efficient manner.

PDF/A has been recognized as the preferred standard for born-digital documents, but it has not been used as the preferred file format for digitized materials. The author recommends that: PDF/A with lossless JPX compressions as the preferred file format; and PDF/A with lossless JPX compressions along with metadata/data as the preferred OAIS SIP container. As a result, the uses reduce costs in digitization and digital preservation and also increase productivity. The author recommends to update the national and international digitization practices using PDF/A.

The purpose of this paper is to examine and illustrate the development of a methodology for generating swarms using lossless flocking.

A general methodology for swarm design is described. Examples of this approach in the literature are examined. A general requirement for lossless flocking is developed. The requirement is used in developing two swarm behaviors.

It is possible to apply the approach to the lossless flocking and to use the swarm condition to develop two swarm behaviors which satisfy this condition in many situations.

This paper illustrates the general swarm engineering method and demonstrates how it can be properly applied.

The swarm engineering method is used to develop the “quark” model, a new physicomimetic model.

The purpose of this paper is to present an update and the latest results from work on a project aimed at enabling waste printed circuit board (WPCB) recycling to become more environmentally friendly and efficient.

A new system was proposed and studied individually under laboratory and factory conditions, which consisted of lossless component removal, component classification, waste crushing/separating processes, and application of crushed non‐metallic particles to develop resin composites.

The use of these novel processes, including component lossless removal, component classification, waste crushing/separating processes, and application of crushed non‐metallic particles to develop resin composites can be combined to give a more sustainable treatment process for printed circuit boards recycling.

Most parts of the WPCBs recycling system have been used. Further development work should be undertaken to establish the whole system in a factory‐scale environment in order to enhance the system efficiency.

The paper details how individual treatment technologies can be combined to enable a more environmentally friendly and efficient system for treatment of WPCBs which offers the benefits of reducing pollution and complete resource recovery for WPCBs.

Perfectly matched layers (PMLs) are used for reflectionless truncation of the problem boundaries in finite element methods applications. In this paper, the method of PMLs is extended to truncate any lossless medium and the method is implemented for the T formulation.

The basic concept behind PMLs is to create an artificial material with a complex and diagonal anisotropic permittivity and permeability. For the A, V formulation PMLs are well known.

It is shown that it is possible to truncate any linear lossless material with PML layers, and if the material has small losses the PML works fine.

In the present paper, an artificial anisotropic lossy material is applied to a 3D edge finite‐element T, formulation to form perfectly matched layers.

Shows that signal quantization can be conveniently captured and quantified in the language of information granules. Optimal codebooks exploited in any signal quantization (discretization) lend themselves to the underlying fundamental issues of information granulation. The paper elaborates on and contrasts between various forms of information granulation such as set theory, shadowed sets, and fuzzy sets. It is revealed that a set‐based codebook can be easily enhanced by the use of the shadowed sets. This also raises awareness about the performance of the quantization process and helps increase its quality by defining additional elements of the codebook and specifying their range of applicability. We show how different information granules contribute to the performance of signal quantification. The role of clustering techniques giving rise to information granules is also analyzed. Some pertinent theoretical results are derived. It is shown that fuzzy sets defined in terms of piecewise linear membership functions with ¹/₂ overlap between any two adjacent terms of the codebook give rise to the effect of lossless quantization. The study addresses both scalar and multivariable quantization. Numerical studies are included to help illustrate the quantization mechanisms carried out in the setting of granular computing.

In this paper, an online convex optimization method for the exoatmospheric ascent trajectory of space interceptors is proposed. The purpose of this paper is to transform the original trajectory optimization problem into a sequence of convex optimization subproblems.

For convenience in calculating accuracy and efficiency, the complex nonlinear terminal orbital elements constraints are converted into several quadratic equality constraints, which can be better computed by a two-step correction method during the iteration. First, the nonconvex thrust magnitude constraint is convexified by the lossless convexification technique. Then, discretization and successive linearization are introduced to transform the original problem into a sequence of one convex optimization subproblem, considering different flight phases. Parameters of trust-region and penalty are also applied to improve the computation performance. To correct the deviation in real time, the iterative guidance method is applied before orbit injection.

Numerical experiments show that the algorithm proposed in this paper has good convergence and accuracy. The successive progress can converge in a few steps and 3–4 s of CPU time. Even under engine failure or mission change, the algorithm can yield satisfactory results.

The convex optimization method presented in this paper is expected to generate a reliable optimal trajectory rapidly in different situations and has great potential for onboard applications of space interceptors.

The originality of this paper lies in the proposed online trajectory optimization method and guidance algorithm of the space inceptors, especially for onboard applications in emergency situations.

A novel many‐valued decomposition within the framework of lossless reconstructability analysis (RA) is presented. In previous work, modified reconstructability analysis (MRA) was applied to Boolean functions, where it was shown that most Boolean functions not decomposable using conventional reconstructability analysis (CRA) are decomposable using MRA. Also, it was previously shown that whenever decomposition exists in both MRA and CRA, MRA yields simpler or equal complexity decompositions. In this paper, MRA is extended to many‐valued logic functions, and logic structures that correspond to such decomposition are developed. It is shown that many‐valued MRA can decompose many‐valued functions when CRA fails to do so. Since real‐life data are often many‐valued, this new decomposition can be useful for machine learning and data mining. Many‐valued MRA can also be applied for the decomposition of relations.

The purpose of this paper is to gain a better understanding on how metasurfaces behave, in terms of currents in each unit cell. A better knowledge of their behavior could lead to an ad-hoc design for specific applications.

The methodology used is both theoretical and numerical; it is based on circuit theory and on an optimization procedure.

The results show that when the knowledge of the current in each unit cell of a metasurface is needed, the most common approximations currently used are often not accurate. Furthermore, a procedure for the termination of a metasurface, with application-driven goals, is given.

This paper investigates the distribution of the currents in a 2D metamaterial realized with magnetically coupled resonant coils. Different models for the analysis of these structures are illustrated, and the effects of the approximations they introduce on the current values are shown and discussed. Furthermore, proper terminations of the resonators on the boundaries have been investigated by implementing a numerical optimization procedure with the purpose of achieving a uniform distribution of the resonator currents. The results show that the behavior of a metasurface (in terms of currents in each single resonator) depends on different properties; as a consequence, their design is not a trivial task and is dependent on the specific applications they are designed for. A design strategy, with lumped impedance termination, is here proposed.