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The overmature Precambrian to Lower Paleozoic marine shales from China contain relatively simple organic matter (OM) composition, which is dominated by in-source solid bitumen (i.e., solid bitumen in the hydrocarbon source rocks). The thermal evolution behavior of the original OM and the determination of thermal maturity in the Precambrian to Cambrian marine shales have been challenging for decades. The vitrinite-like maceral (VLM) is widely present in these marine shales, and its origin is still unknown. To address these issues, the immature Proterozoic Xiamaling shales from China and the immature Cambrian Alum shales from Sweden, and a Chinese immature Carboniferous coal were heat-treated at temperature range of 300 ◦C to 550 ◦C. The carbonized residue of the artificially matured samples was examined for their morphological and reflectance variation, and the results were compared with data on the other overmature natural shales from China and Sweden. OM components are similar in the Xiamaling and Alum immature oil shales, consisting of filamentous algae, matrix bituminite, bituminite, VLM and liptodetrinite, and rare thucholites are present in the Xiamaling shales. The algal-derived OM decomposed gradually due to hydrocarbon generation at 300–350 ◦C. OM is mainly composed of the in-source solid bitumen in the artificially heated shales after 350 ◦C, similar to the overmature Precambrian to Cambrian natural shales, and the in-source solid bitumen gradually loses its mass with increasing thermal maturity. The in-source solid bitumen is derived from the thermal cracking of the retained oil or the direct conversion of algal-derived liptinite macerals (e.g., the bituminite) or their mixture. VLM in the Xiamaling oil shales can not be observed after 350 ◦C, but VLM is still present in the Alum oil shales. It can be inferred that there is a different source of VLM in these shales, and VLM in the Xiamaling oil shales contains more volatile material. The VLM in the Xiamaling shales may be biodegradation products of liptinites under anoxic environments. The origin of VLM in the Cambrian Alum shales requires further study to be verified, although it is certain that graptolites are not its sources. The reflectance of in-source solid bitumen (SBRo) increases with heat-treated temperature in both the Xiamaling shales and the Alum shales, but at different rates, which may be due to the difference of the original kerogen composition in these shales. VLM reflectance (VLMRo) and SBRo in sections perpendicular to bedding can be used to determine the maturation level of the Precambrian-Cambrian sediments. Their relation to equivalent vitrinite reflectance (EqVRo) can be expressed by the following equations: EqVRo = 1.07 × VLMRo – 0.18, EqVRo = 0.87 × SBRo + 0.25 (in the Precambrian sediments) and EqVRo = 1.15 × SBRo + 0.01 (in the Cambrian sediments). This work was supported by the National Natural Science Foundation of China (No. 41773031), the National Key Research and Development Program of China (No. 2017YFC0603102) and the Science Foundation of China University of Petroleum, Beijing (No. 2462020YXZZ021 and 2462021QNXZ001). One of the co-authors (V.S.) wishes to acknowledge the support of OP RDE, MEYS Czech Republic (Reg. No. CZ.02.1.01/0.0/0.0/16_019/0000728), which enabled him to contribute to this study

Awareness of granulated soils’ internal instability is an important parameter when designing granulated filters, and the ability of a granulated soil’s internal stability can be verified using the soil PSD (Particle Size Distribution) curves’ secant slopes. The current work presents a new method to calculate the soil PSD curves’ secant slopes automatically, and a synthetic diagram is presented for the potential examination of the granulated soils’ internal stability. To verify the feasibility and accuracy of this synthetic diagram, 80 specimens of soil were investigated in this work and categorized into two groups: 50 sand–gravel soils and 30 (clay)–silt–sand–gravel soils. The obtained conclusions indicate that the internal stability and instability potentials of sand–gravel soils can be distinguished successfully with a synthetic chart and the Kenney and Lau criterion but cannot be assessed with the Kezdi and Sherard criteria. None of the criteria studied here can be used for the internal stability assessment of silt–sand–gravel and clay–silt–sand–gravel soils.

The thermal maturity of lower Paleozoic graptolite-bearing marine sediments, which host many hydrocarbon deposits worldwide, has long been difficult to determine due to the absence of wood-derived vitrinite particles for conventional vitrinite reflectance. In 1976, graptolite reflectance was introduced as a new indicator for organic maturity of these deposits and has been used since in many regional studies. The majority of these studies, however, were done on a limited sample set and a limited range of thermal maturity, which resulted in a number of controversial views concerning the usefulness of graptolite reflectance as an alternative paleothermal indicator and its correlation with vitrinite reflectance through various proxies. In this paper, we review previous studies and combine those analyses with new data to assess the physical and chemical characteristics of graptolite periderm with increasing thermal maturity. We conclude that graptolite random reflectance (GRor) is a better parameter for the thermal maturity assessment than graptolite maximum reflectance (GRomax) due to the better quality of available data. Combining published data with results of our study of both natural and heat-treated graptolites and vitrinite, we present a new correlation between GRor and equivalent vitrinite reflectance (EqVRo), as EqVRo = 0.99GRor + 0.08. Chemical composition of graptolite periderm is similar to vitrinite; graptolites are mainly kerogen Type II-III, are gas prone and have a substantial hydrocarbon potential. Lower Paleozoic graptolite-bearing organic-rich sediments are important shale gas source rocks and reservoirs globally and make a significant contribution to worldwide petroleum reserves.

This paper describes human hierarchies-of-understanding (HoUs) as frameworks and yardsticks for (1) understanding the effects of semantic technologies on individuals and on society, (2) for designing educational courseware, (3) for designing process flows and content properties in decision support systems, and (4) for measuring the efficiency with which humans use cognitive resources, to include cognitive-cybernetic resources, such as information technology and artificial intelligence. Hierarchies of understanding are comprised of layers of understanding (data, information, knowledge, wisdom, vision). The Vision HoU informs courseware design into the age of ubiquitous artificial intelligence (U.A.I.), an age that may transform societies in turbulent ways in the 2020s. Allocation-of-understanding (AoU) is a speculative distribution of human understanding across layers of data, information, knowledge, wisdom, and vision. The Vision HoU and AoU together illustrate how semantic technologies are facilitating deep human understanding since the beginning of electronic computing, and how such trends can continue into the 2020s. This work concludes by discussing how to design suitable courseware for the age of ubiquitous A.I. (U.A.I.), so that humans play to their cognitive strengths (purpose, creativity, goal-setting, and wise decision-making) while leaving the mundane processing of data, information, and knowledge to semantic technologies and A.I.

An area-efficient parallel VLSI-architecture for the (24,12,8) Golay decoder with an optimized permutation decoding technique based on Wolfmann's algorithm is presented. The decoder uses a look-ahead error-correction structure and a carry-save computation to obtain the highspeed implementation. The hardware complexity was greatly reduced by using a high computation regularity which maps the cyclic syndrome calculation efficiently on a parallel architecture. It is shown that this new architecture for the Golay decoder can be easily implemented in CMOS technology to operate at a data rate above 1 Gbit/s.

An efficient algorithm and the VLSI-architecture for fast soft-decision permutation decoding of the (24,12) extended Golay code are presented. The new decoding technique consists of an optimized permutation decoding with look-ahead error-correction and a modified parity-check soft-decision decoding with reduced test patterns based on the Chase's (1972) algorithm-2. The simulation results for the Gaussian fading channel were found to be only slightly inferior to Chase's algorithm-2 although performing only four test patterns. A parallel VLSI-architecture is also proposed, which will allow for data rates reaching in the hundreds of Mbit/s.

— An efficient ASIC chip of the Golay codec has been designed for channel coding. This paper describes the new architecture used in this chip and the ASIC design. Due to the new architecture which implements a permutation decoding algorithm based on a new minimum permutation set proposed by [6], the codec architecture is relatively simple and a higher speed of the decoding procedure can be achieved compared with the Golay decoder of the decoding algorithms in common use, error-trapping algorithm and step-by-step method. From [7], Kasami's error-trapping decoder requires 46 shift-operations for decoding one completely received word and the modified step-by-step decoder[7] requires 35 shift operations, while our decoder requires only 14 permutation operations, generalized shift operations. Consequently, this decoder can work faster than the Kasami's error-trapping decoder and the modified step-by-step decoder[7].