Rapid and safe wire tension distribution scheme for redundant cable-driven parallel manipulators

A non-iterative analytical approach is investigated to plan the safe wire tension distribution along with the cables in the redundant cable-driven parallel robots. The proposed algorithm considers not only tracking the desired trajectory but also protecting the system against possible failures. This method is used to optimize the non-negative wire tensions through the cables which are constrained based on the workspace conditions. It also maintains both actuators’ torque and cables’ tensile strength boundary limits. The pseudo-inverse problem solution leads to an n-dimensional convex problem, which is related to the robot degrees of redundancy. In this paper, a comprehensive solution is presented for a 1–3 degree(s) of redundancy in wire-actuated robots. To evaluate the effectiveness of this method, it is verified through an experimental study on the RoboCab cable robot in the infinity trajectory tracking task. As a matter of comparison, some standard methods like Active-set and sequential quadratic programming are also presented and the average elapsed time for each method is compared to the proposed algorithm.

Comparative pharmakognostical study of roots of Rosa Majalis Herrm. and Rosa Canina L.

The aim is to conduct a comparative pharmacognostical study of the series of roots of Rosa (R.) majalis Herrm. and Rosa (R.) canina L. with the establishment of diagnostic features of morphological and anatomical structure and boundary limits of numerical indicators of raw materials. Materials and methods. The fresh and dry raw materials were used to study the macroscopic microscopic features by microscope Delta optical BioLight 300 (Poland). Determination of total polyphenols was performed by spectrophotometry (on a spectrophotometer Optizen POP (Korea)) and HPLC (chromatograph an Agilent 1200 3 D LC System Technologies (USA)). Results. The morphological (nature of the surface (periderm) and fracture) and anatomical (color of cell walls and their cavities; location of the sclerenchyma; the presence of a crystalline coating of the sclerenchyma at the root of R. canina; of various elements of the remains of the tetraarchic conducting bundle in the center of the root) diagnostical features of roots of R. majalis and R. Canina were established. Comparing the numerical values of loss on drying (not more than 10 %), total ash (not more than 5 %), extractable matter (not less than 9 %) and the quantitative content of total polyphenols (not less than 4 %) it was determined that both types of raw materials according to these indicators are almost indistinguishable. Conclusions. Loss on drying, total ash, extractable matter and content of total polyphenols of the root of R. majalis and R. canina do not have significant differences, that is why the root of both plant species can be used as medicinal plant raw materials such as “Rose root”. The obtained data will be used in further research when creating methods of quality control of plant raw materials and phytomedicines

Investigating the Viability of Applying a Lower Bound Risk Metric for Altman’s z-Score

The study aimed to build a risk metric for finding the lower boundary limits for Altman’s z-score bankruptcy model. The new metric included a volatility of Altman’s variables and predicted the riskiness of a firm bankrupting in adverse situations. The research examined whether the new risk metric is feasible and whether it provides satisfying outcomes compared to Altman’s z-score values during the same period. The methods to conduct the analysis were based on Value at Risk methodology. The main tools used in constructing the model were Monte Carlo simulation, Lehmer random number generator, normal and t-distribution, matrices and Cholesky decomposition. The sample firms were selected from FTSE 250 index. The important variables used in the analysis were all Altman’s z-score variables, and the period under observation was 2001–2007. The selected risk horizon was the first quarter of 2008. The first results were promising and showed that the model does work to the specified extent. The research demonstrated that Altman’s z-score does not provide a full and accurate overview. Therefore, the lower bound risk metric developed in this research, produces valuable supplementary information for a well-informed decision making. To verify the model, it must be back- and forward tested, neither of which was carried out in this research. Furthermore, the research elaborated on limitations and suggested further improvement options for the model.

Spare half, share the rest: A revised planetary boundary for biodiversity intactness and integrity

Setting clear biodiversity targets is a pervasive challenge1 due to the context-dependent nature of biodiversity that has evaded concise science-based objectives such as the 1.5°C for climate2. Considering the major risk of continued inaction, and further biodiversity loss, it is imperative that the biodiversity community identify similarly operational science-based boundaries supporting the development of targets to safeguard biodiversity and its contributions to human well-being. Confounding goal setting are the two distinct but not mutually exclusive conservation objectives: (1) halting the rampant loss of intact ecosystems, species extinction and population declines, and (2) maintaining biosphere integrity and ecosystem function. We propose a revised planetary boundary for biodiversity: retaining at least half of the area of each terrestrial ecoregion biologically intact to halt the extinction crisis, and maintaining ecosystem integrity across all lands to preserve and regenerate biosphere, ecosystem functions and their contributions to human well-being. We combine four intactness datasets to provide a global assessment and find that 49.6% of the Earth’s land ice-free surface remains intact. While this is promising globally, 69% of 798 unique ecoregions are less than half intact. For ecosystem integrity, we find 18.1% of working lands have ecosystem integrity deficits precluding the provisioning of biosphere and ecosystem functions. Ninety percent of ecoregions have an ecosystem integrity deficit. Globally, intactness and integrity are at boundary limits with degradation of nature critically jeopardizing biosphere capacity to support a safe and just space for humanity. Combined efforts are needed to halt loss of and restore intactness, while regenerating integrity in working lands.

Fuzzy Optimization for the Remediation of Ammonia: A Case Study Based on Electrochemical Oxidation

This case study covers the application of the fuzzy optimization in simultaneously satisfying various constraints that include the compliance of ammonia and nitrate concentrations with stringent environmental standards. Essential components in the multi-criteria decision-making analysis is in the utilization of the Box-Behnken design (BBD) response equations, cost equations and the cumulative uncertainty of response towards the sodium chloride dosage, current density and electrolysis time parameters. The energy consumption in the electrochemical oxidation of ammonia plays an essential role in influencing the total operating cost analysis. The determination of boundary limits based on the global optimum resulted in the complete ammonia removal and USD 64.0 operating cost as its maximum boundary limits and the 40.6% ammonia removal and USD 17.1 as its minimum boundary limits. Based on the fuzzy optimal results, the overall satisfaction level incurred a decrease in adhering with a lower ammonia standard concentration (10 mg/L at 80.3% vs. 1.9 mg/L at 76.1%) due to a higher energy consumption requirement. Global optimal fuzzy results showed to be highly cost efficient (232.5% lower) as compared to using BBD alone. This demonstrates the practicality of fuzzy optimization applications in the electrochemical reactions.

Performance Analysis of Scattering-Level Multiplexing (SLMux) in Distributed Fiber-Optic Backscatter Reflectometry Physical Sensors

Optical backscatter reflectometry (OBR) is a method for the interrogation of Rayleigh scattering occurring in each section of an optical fiber, resulting in a single-fiber-distributed sensor with sub-millimeter spatial resolution. The use of high-scattering fibers, doped with MgO-based nanoparticles in the core section, provides a scattering increase which can overcome 40 dB. Using a configuration-labeled Scattering-Level Multiplexing (SLMux), we can arrange a network of high-scattering fibers to perform a simultaneous scan of multiple fiber sections, therefore extending the OBR method from a single fiber to multiple fibers. In this work, we analyze the performance and boundary limits of SLMux, drawing the limits of detection of N-channel SLMux, and evaluating the performance of scattering-enhancement methods in optical fibers.

From Fundamental Properties to Applications of Surface Activity Investigations: The Kinetic and Thermodynamic Aspects

Interfaces, or surfaces in particular (fluid-solid interfaces), are the boundary limits of two immiscible phases characterized by the surface free energy. Getting insight into their fundamental property is of great importance for both scientific and industrial activities. Such an approach enables us to control the formation and stabilization of colloidal systems, which consist of producing homogenous dispersions from at least two initially immiscible phases. In this mini-review, the kinetic and thermodynamic aspects of fluid surfaces are overviewed. Successively, the main phenomena occurring at the interfaces and the appropriate methodology of investigations, the role of amphiphilic molecules in modifying surface properties and generating various functionalities as a function of their chemical structure, size, and shape, and the current approaches for characterizing interactions as well as synergism or antagonism within mixed systems are treated. Relevant relationships of dynamic fundamental properties to macroscopic consequences at the solid and fluid interfaces of single and mixed amphiphile systems are illustrated.

Fuzzy Optimization on the Synthesis of Chitosan-Graft-Polyacrylic Acid with Montmorillonite as Filler Material: A Case Study

In this paper, the synthesis of a chitosan–montmorillonite nanocomposite material grafted with acrylic acid is presented based on its function in a case study analysis. Fuzzy optimization is used for a multi-criteria decision analysis to determine the best desirable swelling capacity (YQ) of the material synthesis at its lowest possible variable cost. For YQ, the integrating the result’s cumulative uncertainty is an essential element to investigate the feasibility of the developed model equation. The Pareto set analysis is able to set the appropriate boundary limits for YQ and the variable cost. Two case studies are presented in determining the lowest possible cost: Case 1 for maximum YQ, and Case 2 for minimum YQ. These boundary limits were used in the fuzzy optimization to determine its global optimum results that achieved the overall satisfaction ratings of 67.2% (Case 1) and 52.3% (Case 2). The synthesis of the polyacrylic acid/chitosan material for Case 1 resulted in 305 g/g YQ and 10.8 USD/kg, while Case 2 resulted in 97 g/g YQ and 12.3 USD/kg. Thus, the fuzzy optimization approach proves to be a practical method for examining the best possible compromise solution based on the desired function to adequately synthesize a material.

Contract Law Aspects of Sustainable Companies’ Certification in the Global Value Chain

Against the background of economic globalization, sustainable development has attracted increasing attention. Given the boundary limits of jurisdiction, national legal systems are often insufficient to promote sustainability on a transnational level. Intergovernmental agreements and the private self-regulation are at play to fill the gap. As an effective instrument of the latter, sustainable companies’ certification assesses the sustainability of the company as a whole rather than evaluate particular products or services. Although private certification schemes vary greatly across different countries, they are all based on contracts. Three parties are involved in the certification regime, namely certification bodies, companies, and third parties such as customers as well as investors. There are different legal relationships between each two of them. In the case of misleading certification, the German Civil Law provides different approaches to solve disputes according to the legal relationship between the parties.

Automation of the Peak Fitting Method in Bone FTIR Microspectroscopy Spectrum Analysis: Human and Mice Bone Study

FTIR microspectroscopy (FTIRM) is a commonly used nondestructive method to characterise thin bone sections. However, spectrum analysis methods are often highly sensitive to small variations (e.g., boundary limits), thus implying a time-consuming and redundant analysis process. To solve this issue, software has been developed based on several algorithms to automate the analysis. Furthermore, a rigorous framework has been established concerning the peak fitting method to obtain the systematic best potential solution. Validation of the automatic method has been performed by comparison with the manual method. Results and validation proved the reliability of the automatic process. The developed algorithms provide the means necessary to fully compare the results between bone FTIRM studies and between different laboratories.