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61.
This paper deals with the relation between legally protected biodiversity and riverine ecotopes and with the assessment of biodiversity values of the Middle Vistula river valley (Poland). Furthermore, it describes the effects of landscape change on spatial distribution of ecotope patches and biodiversity values in Kazimierski Landscape Park. Biodiversity values were calculated using BIO-SAFE, a model meant to quantify biodiversity and to value ecotopes based on legally protected species. Dissimilarity indices depict high uniqueness of ecotope types regarding their species assemblages (e.g., river dunes, banks and bars). The actual biodiversity values of the river valley in Kazimierski Landscape Park are high in comparison with floodplains of lowland rivers in Western Europe. GIS analyses of remotely sensed ecotope maps show remarkable differences in number, acreage and patchiness of ecotopes for the years 1953 and 2003. The total number of patches increased by almost 44%. Side channels and floodplain lakes became fragmented. The average and total surface area of bush, forest and arable land increased, but decreased for bare soil, pioneer vegetation and grassland. These landscape changes indicate natural vegetation succession, intensification of agriculture and progressive impacts of river regulation. The Vistula river valley still represents high biodiversity values for higher plants, birds, herpetofauna and fish. However, current landscape changes negatively affect potential values for protected and endangered species. Assessments with BIO-SAFE can help to balance biodiversity conservation, river management and landscape planning.  相似文献   
62.
We present an approximate analytical method for the evaluation of packet loss probability in synchronous optical packet-switched networks which operate under limited deflection routing with the contention resolution method based on priorities. Packets are lost because they are removed by nodes. They are removed because they experience too many deflections and stay prohibitively long in the network. Such packets have to be removed because they will be ignored by the transmission protocols (like TCP) and because the quality of their optical signal is unacceptable. Presented are results for the network in the topology of the torus of the two-dimensional grid, which operates at a steady state with the uniform load u, . The strength of our analysis is its novel mathematical approach, which is capable of providing very low packet loss probabilities. For the network composed of 100 nodes, we predict the packet loss probability as low as 10−9 or lower, while simulation provided results only at the order of 10−6. For a given permissible packet loss probability, our analysis provides the maximal network load and the number of allowed deflections. We verify the analysis with simulation in the cases for which simulation gave results.
Jean-Michel FourneauEmail:
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63.
Sobieszek  Adam  Price  Tadeusz 《Minds and Machines》2022,32(2):341-364

This article contributes to the debate around the abilities of large language models such as GPT-3, dealing with: firstly, evaluating how well GPT does in the Turing Test, secondly the limits of such models, especially their tendency to generate falsehoods, and thirdly the social consequences of the problems these models have with truth-telling. We start by formalising the recently proposed notion of reversible questions, which Floridi & Chiriatti (2020) propose allow one to ‘identify the nature of the source of their answers’, as a probabilistic measure based on Item Response Theory from psychometrics. Following a critical assessment of the methodology which led previous scholars to dismiss GPT’s abilities, we argue against claims that GPT-3 completely lacks semantic ability. Using ideas of compression, priming, distributional semantics and semantic webs we offer our own theory of the limits of large language models like GPT-3, and argue that GPT can competently engage in various semantic tasks. The real reason GPT’s answers seem senseless being that truth-telling is not amongst them. We claim that these kinds of models cannot be forced into producing only true continuation, but rather to maximise their objective function they strategize to be plausible instead of truthful. This, we moreover claim, can hijack our intuitive capacity to evaluate the accuracy of its outputs. Finally, we show how this analysis predicts that a widespread adoption of language generators as tools for writing could result in permanent pollution of our informational ecosystem with massive amounts of very plausible but often untrue texts.

  相似文献   
64.
A new, computationally efficient portfolio approach to supplier selection in the presence of supply chain disruption risks is proposed, where the selection of supply portfolios for parts is combined with production scheduling of finished products. Unlike most of reported research on the supply chain risk management which focuses on the risk mitigation decisions taken prior to a disruption, the proposed portfolio approach combines decisions made before, during and after the disruption. The two decision-making approaches are considered: an integrated approach with the perfect information about the future disruption scenarios, and a hierarchical approach with no such information available. In the integrated approach, which accounts for all potential disruption scenarios, the primary supply portfolio that will hedge against all scenarios is determined along with the recovery supply portfolio and production schedule for each scenario. In the hierarchical approach, first the primary supply portfolio is determined, and then, when a primary supplier is hit by a disruption, the recovery supply portfolio is selected. For the integrated and the hierarchical decision-making, mixed integer programming models are developed with the two risk-neutral conflicting objectives that account for both time and cost of recovery: minimising expected cost or maximising expected service level. The findings indicate that for both objectives, the integrated decision-making selects a more diversified primary supply portfolio than the hierarchical approach and when all primary suppliers are shutdown by disruption, a single sourcing recovery portfolio is usually selected.  相似文献   
65.
Summary: This paper reports the phase behavior of photochemically crosslinked poly(butyl acrylate) networks in nematic liquid crystal (LC) solvents. The swelling properties are studied as a function of temperature for two low molecular weight nematic LCs, 4‐cyano‐4′‐pentylbiphenyl (5CB) and the eutectic mixture of cyanoparaphenylenes (E7). Chemically crosslinked polymer networks were formed by the UV radiation of initial solutions of the reactive monomer, butyl acrylate, a crosslinker (hexanediol diacrylate), and a photoinitiator. To obtain different network densities, the ratio of butyl acrylate to hexanediol diacrylate was varied prior to polymerization/crosslinking reactions. Immersion in an excess of the LC solvent allowed for the measurement of size increase by polarized optical microscopy in terms of temperature. Length, width, and diagonal ratios were calculated considering swollen to dry network states of the samples. In general, swelling leads to an increase in the network size by increasing the temperature with a significant dependence on the degree of crosslinking. A large shift in the swelling ratio was found in the vicinity of the nematic to isotropic transition temperatures of the LCs.

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66.
The antiplasticizing effect of ester derivatives of bisphenol A: 1,1-bis(4-hydroxyphenyl)-2,2-propane diacetate (DAPP), 1,1-bis(4-hydroxy-3,5-dichlorophenyl)-2,2-propane diacetate (DACPP), 1,1-bis(4-hydroxy-3,5-dibromophenyl)-2,2-propane diacetate (DABPP), 1,1-bis(4-hydroxy-3,5-dichlorophenyl)-2,2-propane dibenzoate (DBCPP), 1,1-bis(4-hydroxy-3,5-dichlorophenyl)-2,2-propane di-2,4-dichlorobenzoate (DCBCPP) on polycarbonate was investigated. Obtained results indicate that antiplasticizing abilities of these compounds depend on the number of polar groups in the molecule, as well as on the possibility of tight filling the free volume by the molecules in polymer–antiplasticizer system.  相似文献   
67.
A series of 21 novel, structurally diverse ω‐(isothiocyanato)alkylphosphinates and phosphine oxides (ITCs) were designed and synthesized in moderate to good yields. The synthesized compounds were evaluated for in vitro antiproliferative activity using LoVo and LoVo/DX cancer cell lines. The biological activity of the synthesized compounds was higher than that of natural isothiocyanates such as benzyl isothiocyanate or sulforaphane. The antiproliferative activity of selected ITCs was also tested on selected cancer cell lines: A549, MESSA and MESSA/DX‐5, HL60 and HL60MX2, BALB/3T3, and 4T1. These compounds were assessed for their mechanism of action as inducers of cell‐cycle arrest and apoptosis. Ethyl (6‐isothiocyanatohexyl)(phenyl)phosphinate ( 71 ) was tested in vivo on the 4T1 cell line and demonstrated moderate antitumor activity, similar to that benzyl isothiocyanate and cyclophosphamide.  相似文献   
68.
69.
Minimum energy control problem for the fractional positive electrical circuits with bounded inputs is formulated and solved. Sufficient conditions for the existence of solution to the problem are established. A procedure for solving of the problem is proposed and illustrated by example of fractional positive electrical circuit.  相似文献   
70.
A method for ultrasonic synthetic aperture imaging using finite-sized transducers is introduced that is based on a virtual source (VS) concept. In this setup, a focused transducer creates a VS element at its focal point that facilitates the use of synthetic aperture focusing technique (SAFT). It is shown that the performance of the VS method may be unsatisfactory due to the distortion introduced by the diffraction effects of the aperture used for creating the VS element. A solution to this problem is proposed that consists of replacing the classical SAFT by the extended synthetic aperature focusing technique (ESAFT) algorithm presented in our earlier works. In ESAFT, the full geometry of the VS is modeled, instead of applying the simplified point source approximation used when VS is combined with classical SAFT. The proposed method yields a substantial improvement in spatial resolution compared to that obtained using SAFT. Performance of the proposed algorithm is first demonstrated on simulated data, then verified on real data acquired with an array system.  相似文献   
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