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We give a canonical representation for minimal acyclic deterministic finite automata (MADFA) with n states over an alphabet of k symbols. Using this normal form, we present a method for the exact generation of MADFAs. This method avoids a rejection phase that would be needed if a generation algorithm for a larger class of objects that contains the MADFAs were used. We give upper and lower bounds for MADFAs enumeration and some exact formulas for small values of n.

Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid-state plasmas when a strong magnetic field is applied. In our device the helicons were excited by RFs (the range 100-2000 MHz) much higher than the helicon generation frequency (the main peak at 20 MHz). The excitation of helicons in this case may be described by the effect similar to the Combination Scattering (Raman effect) when a part of the high RF wave energy that passes through the active material is absorbed and re-emitted by the magnetized solid-state plasma. It is expedient to call this experimental device a Helicon Maser (HRM) and the higher frequency e/m field - a pumping field. In full analogy with the usual Raman maser (or laser) the magnetized semiconductor sample plays the role of active material and the connecting cable - the role of high quality external resonator.

We show that the probability of generating an iterated wreath product of non-abelian finite simple groups converges to 1 as the order of the first simple group tends to infinity provided the wreath products are constructed with transitive and faithful actions. This has the consequence that the profinite group which is the inverse limit of these iterated wreath products is positively finitely generated.

In this paper, we show how it is possible to obtain mass generation in the context of non-Abelian gauge field theory, using a noncommutative spacetime. This is further confirmed by the modified dispersion relation that results from such a geometry. Other effects in the domain of ultra high energy gamma rays and cosmic rays are also deduced and it is pointed out that we might already have observed such effects.

In this paper, we determine the finite classical simple groups of dimension n = 3, 5 which are (2, 3)-generated (the cases n = 2, 4 are known). If n = 3, they are PSL₃(q), q ≠ 4, and PSU₃(q²), q² ≠ 9, 25. If n = 5 they are PSL₅(q), for all q, and PSU₅(q²), q² ≥ 9. Also, the soluble group PSU₃(4) is not (2, 3)-generated. We give explicit (2, 3)-generators of the linear preimages, in the special linear groups, of the (2, 3)-generated simple groups.

In this paper we give explicit $(2,3)$-generators of the finite unitary groups ${\mathrm{\text{SU}}}_6(q^2)$, for all $q$. They fit into a uniform sequence of likely $(2,3)$-generators for all $n\ge 6$.

We present an easy synthetic method for the fabrication of encapsulated nanosized semiconductor CdE [E $=$ S, Se and Te] within the core of carbon capsule. We also discuss the growth of CdSC and neat CdS nanocrystals on stainless steel coupons (SSC) by a reaction under autogenic pressure at elevated temperature (RAPET) technique. The thermal decomposition of mixture of Cd(acetate)₂ and sulfur, selenium and tellurium was carried out at 750${}^{\circ }$C under air for 3h. The synthesized products were systematically characterized by X-ray powder diffraction, scanning electron microscopy (SEM) and transmission electron microscopy. Carbon matrix, with an average diameter of 250nm, encapsulated several nanometric-sized CdS nanocrystals, as evidenced from high resolution SEM (HRSEM). We examined the optical properties of this core/shell CdS@C and nonencapsulated CdS nanocrystals and found that both core shell and neat CdS nanocrystals show emission in the pohotoluminescence (PL) spectrum.

Based on the literature about the role of rising nationalism in recent world politics, this paper proposes a nationalism-oriented causal model to explain the voting choices of different social groups. With an interest-identity framework, this generic model is applied to Taiwan’s 2016 presidential election to examine whether and to what extent 11 causal mechanisms influence the voting choices of four groups defined by generation, class, and ethnicity. The findings not only reveal generational, class-based, and ethnic differences in Taiwanese voting behavior; they also show that the election was largely one of identity politics centered around the issues of national identity and democratic identification, making the “interest card” played by Beijing less effective in swaying voter choices. This explains why Beijing’s divide-and-conquer economic policy successfully divided Taiwanese voters but failed in the end to prevent the pro-independence candidate from winning the election. The findings also indicate that the economic concerns of voters promoted both their Taiwanese identity and support for Taiwan independence, while identification with Taiwan’s democracy contributed directly to the former and only indirectly to the latter. Overall, the model presents a more fine-grained analysis of nationalist politics and may be applied to the studies of other political behaviors involving nationalism.

The sets of records developed for the SAC Steel Project are classified according to the level of seismic hazard and specific geographic region, and have been used extensively for structural response and seismic hazard analyses. This study presents a parametric analysis of these record data sets for generation of uniform hazard earthquake and near-field records. The record parameters define far-field characteristics such as power spectral density and envelope function, and near-field effects such as acceleration pulse, power spectral density and envelope function. The proposed method for generation of near-field records uses the decomposing capabilities of wavelet transform on earthquake records. A set of uniform hazard earthquake accelerograms and near-field ground motions is generated based on the record parameters. The generated uniform hazard earthquake accelerograms representing a uniform level of seismic hazard for a particular geographic region involves seismic hazard studies, calibrated attenuation relationships, and local site amplification models. In order to assess the reliability and efficiency of the presented method, the statistical response spectra obtained from the generated accelerograms have been compared with those from the actual records. The obtained results showed that there is a good compatibility between the response spectra of the generated and actual records in the most of the frequencies.

Wind turbines and Solar Photovoltaic (PV) electric energy generators are the lowest cost producers of electricity available in 2019, costing about half as much as a new coal plant’s electric energy (Lazard’s Levelized Cost of Energy Analysis, 2018). They have the important characteristic of delivering electricity without releasing greenhouse gases like carbon dioxide (CO₂). Yet, almost all experts and plans for the future say that wind and solar will not be dominant contributors to electricity generation for the next couple of decades. They say we must continue fossil fuels with their associated greenhouse gases because of problems with renewable generators…

Radio frequency (RF) magnetoplasmic waves known as helicons will propagate in solid-state plasmas when a strong magnetic field is applied. In our device the helicons were excited by RFs (the range 100-2000 MHz) much higher than the helicon generation frequency (the main peak at 20 MHz). The excitation of helicons in this case may be described by the effect similar to the Combination Scattering (Raman effect) when a part of the high RF wave energy that passes through the active material is absorbed and re-emitted by the magnetized solid-state plasma. It is expedient to call this experimental device a Helicon Maser (HRM) and the higher frequency e/m field - a pumping field. In full analogy with the usual Raman maser (or laser) the magnetized semiconductor sample plays the role of active material and the connecting cable - the role of high quality external resonator.

Many musculoskeletal diseases and trauma can potentially be alleviated or cured by stem cell and tissue engineering approaches. Most musculoskeletal tissues are derived from mesenchymal stem cells (MSCs), which natively differentiate into chondrocytes, osteoblasts, adipocytes, fibroblasts, myocytes, etc. Although MSCs are assisted by other cell populations such as the hematopoietic lineages, there is no doubt that MSCs are the progenitors of the building blocks of the musculoskeletal system during development. The roles of MSCs in musculoskeletal regeneration have been demonstrated numerous times in various musculoskeletal tissues, and yet are not completely understood. Nonetheless, musculoskeletal regeneration often, but not always, requires biomaterial scaffolds that need to accommodate various cellular functions such as adherence, proliferation, and differentiation. Musculoskeletal scaffolds must also provide the structural similarity, mechanical strength, diffusion, and gas exchange needs of the tissues or organs to be regenerated. These conflicting needs of musculoskeletal scaffolds for cellular function and physical attributes of the regenerating tissue remain a challenge. Although a great deal can and should be learned from in vitro systems, follow-up in vivo studies are needed as a testing bed for cell-scaffold constructs. Additionally, there is a need to test the efficacy of musculoskeletal constructs in frequently inflammatory and diseased models. Furthermore, musculoskeletal regeneration often requires the engineering of two or more cell types, such as osteochondral, fibro-osseous, fibromyogenic, and myo-osseous tissues. This review provides a glimpse of selected approaches for the engineering of complex musculoskeletal tissue.

The problem of assembly process planning is critical for the automation and integration of production, due to the combinatorial complexity and the requirement of both flexibility and productivity. This chapter presents an integrated knowledgebased approach and system for automatic generation, evaluation and selection, and visualization of assembly sequences. In this chapter, information and knowledge about a product and its assembly processes is modeled and represented by using integrated object model and generic P/T net formalisms. The comprehensive knowledge-based integration coordinates design and assembly sequence planning in the complex interactions and domain knowledge between the technical and economical aspects. By using the integrated representational model, all feasible assembly sequences are generated by decomposing and reasoning the leveled feasible subassemblies, and represented through Petri net modeling. Both qualitative and quantitative constraints are then used to evaluate each assembly part and operation sequence individually and the entire sequences as well. Based on assemblability analysis and evaluation and predefined task time analysis, estimates are made for the assembly time and cost and operation's difficulty of product when each of these sequences is used. Some quantitative criteria such as assembly time and cost, operation difficulty and part priority index are applied to select the optimal assembly sequence. Finally, a prototype integrated knowledge-based assembly planning system is developed to achieve the integration of generation, evaluation and selection, and visualization of the assembly sequences.

Approximation algorithms for NP-hard problems must often be evaluated empirically. This creates a need for suitable test cases. Test cases with known answers and varied characteristics can be particularly useful. This paper considers some of the computational complexity issues involved in the generation of instances of NP-hard problems, in such a way that the answers for the instances are known, and such that the instances have certain desirable properties such as hardness and diversity.

This paper presents small pendulum type wave energy generation system, and explains its working principle. Motion model and equation of pendulum based on wave theory are established. Si7mulation by MATLAB and generation performance analysis are carried out.