Spatial Learning and Action Planning in a Prefrontal Cortical Network Model

The interplay between hippocampus and prefrontal cortex (PFC) is fundamental to spatial cognition. Complementing hippocampal place coding, prefrontal representations provide more abstract and hierarchically organized memories suitable for decision making. We model a prefrontal network mediating distributed information processing for spatial learning and action planning. Specific connectivity and synaptic adaptation principles shape the recurrent dynamics of the network arranged in cortical minicolumns. We show how the PFC columnar organization is suitable for learning sparse topological-metrical representations from redundant hippocampal inputs. The recurrent nature of the network supports multilevel spatial processing, allowing structural features of the environment to be encoded. An activation diffusion mechanism spreads the neural activity through the column population leading to trajectory planning. The model provides a functional framework for interpreting the activity of PFC neurons recorded during navigation tasks. We illustrate the link from single unit activity to behavioral responses. The results suggest plausible neural mechanisms subserving the cognitive “insight” capability originally attributed to rodents by Tolman & Honzik. Our time course analysis of neural responses shows how the interaction between hippocampus and PFC can yield the encoding of manifold information pertinent to spatial planning, including prospective coding and distance-to-goal correlates

Ground-water environmental pollution with polycyclic aromatic hydrocarbons near a refinery

Rafinerie ropy naftowej należą do tych zakładów przemysłowych, w których najczęściej dochodzi do skażenia środowiska gruntowo--wodnego różnego rodzaju węglowodorami. Skażenie gleb i wód może wystąpić zarówno z powodu rozszczelnienia instalacji produkcyjnych, jak i podczas magazynowania ropy naftowej oraz jej produktów. Jednymi z bardziej toksycznych są wielopierścieniowe węglowodory aromatyczne (WWA), których znaczne ilości powstają w przetwórstwie ropy naftowej i surowych olejów. W artykule przedstawiono badania stanu jakościowego środowiska gruntowo-wodnego w zakresie zawartości wielopierścieniowych węglowodorów aromatycznych na terenie lokalizacji jednej z polskich rafinerii nafty. Na podstawie porównania wyników badań geochemicznych i hydrochemicznych z wartościami progowymi w zakresie wymaganych standardów jakościowych środowiska gruntowo-wodnego stwierdzono, że zarówno grunty, jak i wody podziemne są zanieczyszczone WWA ponad ustalone standardy, co kwalifikuje je do remediacji.Oil refineries belong to industrial plants frequently polluting the ground-water environment with a variety of hydrocarbons. Ground and water contamination may be caused by leakages in the production installments and also during oil and oil-products storing. One of the most toxic ones are polycyclic aromatic hydrocarbons, produced in considerable quantities in the course of oil and crude oils processing. The quantitative state of the ground-water environment with respect to the polycyclic aromatics near one of the Polish oil refineries has been analyzed in this paper. Basing on the comparison of geochemical and hydrochemical results with threshold environmental standards, a conclusion was drawn that both grounds and underground waters are contaminated with polycyclic aromatics above the admissible values, qualifying them for remediation procedures to be applied

Groundwater contamination with hydrocarbons near an oil refinery

Rafinerie ropy naftowej należą do zakładów przemysłowych, w których najczęściej dochodzi do zanieczyszczenia środowiska wodnego różnego rodzaju węglowodorami ropopochodnymi. Zanieczyszczenie wód może być spowodowane rozszczelnieniem zarówno instalacji produkcyjnych, zbiorników magazynowych ropy naftowej oraz jej produktów, jak i instalacji do napełniania cystern produktami naftowymi. W artykule przedstawiono wyniki badań stanu jakościowego wód podziemnych w zakresie zawartości węglowodorów na terenie jednej z polskich rafinerii ropy naftowej. Na podstawie porównania wyników badań hydrochemicznych próbek wód podziemnych do wartości progowych w zakresie wymaganych standardów jakościowych środowiska wodnego stwierdzono, że wody podziemne są zanieczyszczone substancjami węglowodorowymi ponad ustalone standardy, co kwalifikuje je do oczyszczaniaOil refineries belong to the industrial plants where water environment is most frequently contaminated with hydrocarbons. Water may be contaminated through leaking production installments, storages of oil and oil products, as well as the installment for filling the cisterns with oil products. The results of quantitative analyses of groundwaters for the hydrocarbons content in the area of an oil refinery in Poland is presented in the paper. The comparison of the standard water environment quality threshold values and the results of analyses of groundwater samples revealed that hydrocarbon contaminations in the analysed groundwaters exceeded the admissible standards, and thus, have to be cleane

Policing the Night: Integration of Night Vision Goggles into Airborne Law Enforcement Operations

NRC publication: Ye

Detection and discrimination of motion-defined form: Implications for the use of night vision devices

Superimposed luminance noise is typical of imagery from devices used for low-light vision such as image intensifiers (i.e., night vision devices). In four experiments, we measured the ability to detect and discriminate motion-defined forms as a function of stimulus signal-to-noise ratio at a variety of stimulus speeds. For each trial, observers were shown a pair of image sequences- one containing dots in a central motion-defined target region that moves coherently against the surrounding dots, which moved in the opposite or in random directions, while the other sequence had the same random/uniform motion in both the center and surrounding parts. They indicated which interval contained the target stimulus in a two-interval forced-choice procedure. In the first experiment, simulated night vision images were presented with Poisson-distributed spatiotemporal image noise added to both the target and surrounding regions of the display. As the power of spatiotemporal noise was increased, it became harder for observers to detect the target, particularly at the lowest and highest dot speeds. The second experiment confirmed that these effects also occurred with low illumination in real night vision device imagery, a situation that produces similar image noise. The third experiment demonstrated that these effects generalized to Gaussian noise distributions and noise created by spatiotemporal decorrelation. In the fourth experiment, we found similar speed-dependent effects of luminance noise for the discrimination (as opposed to detection) of the shape of a motion-defined form. The results are discussed in terms of physiological motion processing and for the usability of enhanced vision displays under noisy conditions. \ua9 2013 IEEE.Peer reviewed: YesNRC publication: Ye

Environmental aspects of executing and exploitation underground heat exchangers

Wykorzystanie górotworu jako dolnego źródła dla pomp ciepła wiąże się z koniecznością wykonania otworowych wymienników ciepła pośredniczących w jego wymianie. Pozwala to pozyskać czystą energię, a więc przyczynia się do ograniczenia emisji gazów cieplarnianych. Proces instalowania i użytkowania wymienników otworowych niesie jednak pewne zagrożenia dla środowiska, które przy odpowiednim postępowaniu można ograniczyć do minimum. W artykule opisano czynniki szkodliwe występujące podczas wykonywania i eksploatowania otworowych wymienników ciepła.The use ground as reservoir of low temperature heat to heat pumps heating and cooling system is connected with necessity installing underground heat exchangers. Therefore pure energy from earth causes decreasing greenhouse gases to atmosphere and improvement of state of environment. The realization of installation taking the energy from the ground and they exploitation make possible pronouncement damage for place, where execute underground heat exchangers. Near good practice threats this are possible to limit to minimum. In this paper describe some faults influence on surroundings during drilling and exploitation of underground heat exchangers system

Percussion-rotary method of drilling large-diameter dewatering wells in ‘Bełchatów’ liginte mine

Lignite opencast extraction can be performed after prior dewatering of the rock mass. Most frequently it is realized with large-diameter dewatering wells which have been mostly drilled with the invert mud rotary method and airlift. This method allows for quick drilling in lithologically diversifi ed aquifers, minimizing the negative impact of mud on the near-well zone. When drilling in dewatered carbonate rocks with the stone runs or well developed karst the effi ciency of this method considerably decreases. The technical and technological aspects of use of downhole hammers for drilling large-diameter dewatering wells in diffi cult geological conditions are discussed in the paper. Thanksto the use of this method for drilling wells in ‘Bełchatów’ Lignite Mine the drilling rate could be increased and the number of complications and drilling failures lowered

Night vision devices in the airborne platform: predicted future developments

NRC publication: Ye

Qualitative Evaluation of the NVG Compatibility of the SkyTrac CDP-250 and DVI-250 Units

NRC publication: Ye