Photography has a special way of bestowing extraordinary meaning on ordinary subjects – we discuss it with Izabela Łapińska from the Leon Schiller National Film School in Łódź.
The word “sensitivity” has many meanings, ranging from more mundane technical senses, to meanings specific to statistics and machine learning, all the way to the most human understanding of the concept – that of tender emotions.
Four dye-sensitized solar cell devices are designed and fabricated based on natural dyes extracted from Celosia Cristata, Saffron, Cynoglossum, and eggplant peel, as photosensitizers. The UV–vis technique has been served to determine maximum absorption of natural extract and pre-dyed photoanode. The Fourier transform infrared (FT-IR) was employed to cover the presence of functional groups. The cyclic voltammetry method has been employed to assess the possibility of charge transfer from dried natural dyes to the photoelectrode. The performance of natural-based dye-sensitized solar cells is determined subsequently. The highest power conversion efficiency was ca. 1.38%, which belonged to Celosia Cristata extract. The devices were examined for higher efficiencies, individually, co-sensitized arrangement and/or in tandem with each other.
Since 1999 studies are conducted of specific form of corruption known as ‘state capture’. This term refers to a situation in which individual agents and groups of interests are seeking to shape and affect the process of formulating regulations to their advantage through illicit and non-transparent means. In other words, state capture is an attempt of a group of interest to change institutionalized rules of the market game in a way favorable for them in order to gain political rents. This paper is a reconstruction of economic studies on phenomenon of state capture. The first part of paper is devoted to presentation of state capture in context of other forms of corruption. It focuses mainly on series of survey studies known as Business Environment and Enterprise Performance Survey (BEEPS) conducted by World Bank and EBRD. The second part of the paper is a critical analysis of state capture conception and methodology. The text points out limitations of economical research procedures in domain of corruption analysis. Methodological difficulties and restrictions of conception of state capture are discussed on an example of chosen political affair – Buchacz triangle. The paper ends with sociological reinterpretation of conception of state capture.
Blockchain technology may soon profoundly transform the economic, financial, and legal reality of entire societies and even systems of government. But is this new financial instrument (a new form of ”tender,” in the sense of money offered for payment) sensitive only to the rules of free-market economics, or also to human rights and sensibilities? Whose needs will determine the direction of change: those of ordinary people, or the financial elite?
Sensors designed by Polish engineers help detect traces of life beyond Earth. Adam Piotrowski of Vigo System tells us what else these devices can do.
Metaphysical tenderness does exist – it lies at the core of joyful acceptance of all manifestations of life on both sides of our skin and determines our zest for life, perhaps to a greater extent than money, fame, or origin.
Olga Tokarczuk is among the pioneers exploring a certain turn towards emotions, artistic efforts that value sensation over thought.
A highly sensitive photonic crystal fiber based on the surface plasmon resonance (PCF-SPR) biosensor for the detection of the density alteration in non-physiological cells (DANCE) is described. Human acute leukemia cells are determined by the discontinuous sucrose gradient centrifugation (DSGC) in which the cells are separated into several bands. The separated cells with different intracellular densities and refractive indexes (RI) ranging from 1.3342 to 1.3344 are distinguished in situ by means of the differential transmission spectrum. The biosensor shows a maximum amplitude sensitivity of 2000 nm/RIU and resolution as high as 5 × 10−5 RIU. According to the wavelength interrogation method, a maximum spectral sensitivity of 9000 nm/RIU in the sensing range between 1.33 and 1.53 is achieved, corresponding to a resolution as high as 1.11 × 10−5 RIU for the biosensor. The proposed PCF-SPR biosensor has promising application in biological and biochemical detection.
A novel methodology was implemented in the present study to concurrently control power conversion efficiency (η) and durability (D) of co-sensitized dye solar cells. Applying response surface methodology (RSM) and Desirability Function (DF), the main influential assembling (dye volume ratio and anti-aggregation agent concentration) and operational (performance temperature) parameters were systematically changed to probe their main and interactive effects on the η and D responses. Individual optimization based on RSM elucidated that D can be solely controlled by changing the ratio of vat-based organic photosensitizers, whereas η takes both effects of dye volume ratio and anti-aggregation concentration into account. Among the studied factors, the performance temperature played the most vital role in η and D regulation. In particular, however, multi-objective optimization by DF explored the degree to which one should be careful about manipulation of assembling and operational parameters in the way maximization of performance of a co-sensitized dye solar cell.
Dye sensitized solar cells (DSSCs) based on indigo dyes exhibit suitable conversion efficiency. These organic dyes have been undergone for aggregation. Electron transfer process is reduced due to an aggregation of molecular dyes. Therefore, anti-aggregation agent is commonly utilized in fabrication of DSSCs. In the present study, two anti-aggregation agents namely as 3α,7α-dihydroxy-5β-cholanic acid (cheno) and 3α,7α,12α-trihydroxy-5β-cholanic acid (cholic acid) were added to indigo dye solution in DSSCs in order to determine the photovoltaic parameters such as short circuit photocurrent, open circuit voltage and conversion efficiency of each individual dye in the absence and presence of anti-aggregation agents. The results show that the conversion efficiencies are improved with reduced aggregation. Spectrophotometric evaluations of the indigo dyes in solution and on a TiO2 substrate were carried out in the absence and presence of anti-aggregation agents in order to estimate changes in the status of the dyes in different environments. J-type aggregates on the nano TiO2 are reduced in the presence of anti-aggregation agents.
Control of the technological processes of coal enrichment takes place in the presence of wide disturbances. Thus, one of the basic tasks of the coal enrichment process control systems is the stabilization of coal quality parameters at a preset level. An important problem is the choice of the controller which is robust for a variety of disturbances. The tuning of the controller parameters is no less important in the control process . Many methods of tuning the controller use the dynamic characteristics of the controlled process (dynamic model of the controlled object). Based on many studies it was found that the dynamics of many processes of coal enrichment can be represented by a dynamic model with properties of the inertial element with a time delay. The identification of object parameters (including the time constant) in industrial conditions is usually performed during normal operation (with the influence of disturbances) from this reason, determined parameters of the dynamic model may differ from the parameters of the actual process. The control system with controller parameters tuned on the basis of such a model may not satisfy the assumed control quality requirements.
In the paper, the analysis of the influence of changes in object model parameters in the course of the controlled value has been carried out. Research on the controller settings calculated according to parameters T and τ were carried out on objects with other parameter values. In the studies, a sensitivity analysis method was used. The sensitivity analysis for the three methods of tuning the PI controller for the coal enrichment processes control systems characterized by dynamic properties of the inertial element with time delay has been presented. Considerations are performed at various parameters of the object on the basis of the response of the control system for a constant value of set point. The assessment of considered tuning methods based on selected indices of control quality have been implemented.
Marta Wrzosek from the Faculty of Biology, University of Warsaw talks about the fascinating and complex world of fungi and examines the complicated role of language in science popularization.
A failure analysis of Babar dam on the El Arab River was performed to highlight the impact of flood wave and velocities on the four villages downstream of the dam; Hella, Khérenne, Chebla and El Oueldja. The simulation of wave propagation along the El Arab River under several scenarios was performed by the hydraulic HEC-RAS model. This model is dedicated to the description of floods at the dam following a breach in the dike. The main factors considered in this simulation include the level of flood water, the flood hydrograph, and the typical scenario for this breach. The flood risk analysis revealed that the maximum of flood wave flow registered at the breach is (Qmax = 9253.02 m3∙s–1), and is beginning to mitigate downstream of the dam along the El Arab River where it reached at the last village with a low flow (Q = 1110.64 m3∙s–1). This simulation allowed drawing the risk map which showed the areas threatened by flood wave resulting from a total failure of the work, and consequently required a plan of security measures to moderate as much as possible the consequences of floods. A sensitivity analysis was conducted to approach the parameters of impact of the breach on the dam failure scenario. It was confirmed that these parameters as formulation time, breach width and side slope have a great influence on the dam failure scenario with the four adjustments (±20 and ±50).