Optimizing PAT data transmission: assessing the accuracy of temperature summary data to estimate environmental conditions

Pop-up archival tags (PAT) provide summary and high-resolution time series data at predefined temporal intervals. The limited battery capabilities of PATs often restrict the transmission success and thus temporal coverage of both data products. While summary data are usually less affected by this problem, as a result of its lower size, it might be less informative. We here investigate the accuracy and feasibility of using temperature at depth summary data provided by PATs to describe encountered oceanographic conditions. Interpolated temperature at depth summary data was found to provide accurate estimates of three major thermal water column structure indicators: thermocline depth, stratification and ocean heat content. Such indicators are useful for the interpretation of the tagged animal's horizontal and vertical behaviour. The accuracy of these indicators was found to be particularly sensitive to the number of data points available in the first 100 m, which in turn depends on the vertical behaviour of the tagged animal. Based on our results, we recommend the use of temperature at depth summary data as opposed to temperature time series data for PAT studies; doing so during the tag programming will help to maximize the amount of transmitted time series data for other key data types such as light levels and depth.

In situ transmission electron microscopy ion irradiations of model iron-chromium alloys

Iron-chromium alloys are used as a model to study the microstructural evolution of defects in irradiated structural steel components of a nuclear reactor. We examine the effects of temperature and chromium concentration on the defect evolution and segregation behavior in the early stages of damage. In situ irradiations are conducted in a transmission electron microscope (TEM) at 300°C and 450°C with 150keV iron ions in single crystal Fe14Cr and Fe19Cr bicrystal to doses of 2E15 ions/cm^2. The microstructures resulting from annealing and irradiation of the alloy are characterized by analysis of TEM micrographs and diffraction patterns and compared with those of irradiated pure iron. We found the irradiation temperature to have little effect on the microstructural development. We also found that the presence of chromium in the sample leads to defect populations with small average loop size and no extended or nested loop structures, in contrast to the populations of large extended loops seen in irradiated pure iron. A very weak dependence was found on the specific chromium content of the alloy. Chromium was shown to suppress defect growth by inhibiting defect mobility in the alloy. While defects in pure iron are highly mobile and able to grow, those in the FeCr alloys remained small and relatively motionless due to the pinning effect of the chromium.

Transmission Easement and Adverse Possession of Transmission Easement in the Polish Law

The object of analysis in the text are the issues concerned with the transmission easement and the adverse possession thereof on the grounds of the Polish law. The text features: (1) a historical outline of the solutions concerned with easements in the Polish law following 1945, (2) the institution of transmission easement introduced in 2008 and the solutions concerned with the claims for the establishment thereof at court, (3) the institution of adverse possession of transmission easement pursuant to civil law regulations, judicature and the legal doctrine. On account of the need to elaborate the wide-ranging legal issues concerned with the transmission easement in this text, the analysis embraces two research questions giving rise to the following conclusions: (1) What function is performed by the institution of transmission easement in the system of civil-law relations in the Polish law? The legislator in the articles introducing a transmission easement ossified the solutions functioning in the judicature of the Polish courts before 2008. The legal interpretation took a turn for clarification, that is for the establishment of a norm in the situation where its comprehension was dubious. It is noteworthy that in the period prior to 2008, the law provided for easement appurtenant, and on account of the usual course of judicial decisions also for easement appurtenant with the content corresponding to transmission easement. In 2008 these two “legal existences” were supplemented with a transmission easement, which nevertheless failed to resolve all the legal problems; nay, this gave rise to even more problems, e.g. the one of non-establishment of interpolar norms which would address the issues arising in connection with the use of various easement institutions in legal transactions. While amending the civil law, the legislator aimed to bring order to legal transactions by streamlining the unregulated actual state of easement in relation to transmission infrastructure, but also in relation to the situations where an easement was yet to be established and a facility yet to be constructed. Thus, such action is intended to regulate the disorderly legislation in force as well as to safeguard investment processes. This is of particular significance, for example, for energy companies which are burdened with statutory public-law obligations as regards securing energy supplies and providing for the development of energy infrastructure. Hence, the de facto introduced civil-law solutions indirectly served to realise the principles of the doctrine of easement in the public interest. (2) What legal problems in the civil-law relations does the application of the institution of transmission easement by adverse possession entail? On account of the functioning of various institutions of easement, that is (1) an easement appurtenant, (2) an easement appurtenant with the content corresponding to a transmission easement, and as of 2008 (3) a transmission easement, a problem arose as to which of the given easements companies exercised in particular periods, all the more so because before 1989 the State Treasury owned them and many of the transmission facilities were put in place by virtue of administrative decisions. The commonly held belief is that in the period of “society-oriented economy” as well as up to 2008 infrastructure companies could exercise an easement appurtenant which corresponded to the content of a transmission easement. Therefore, in such a case the running of the prescriptive period should allow for the general rules laid down for an easement appurtenant. Apart from the problem of the relation of a capacity to exercise a right to property and the free development of civil-law relations before 1989, the recognition of the running of prescriptive periods – given the functioning of the three various easements as legal institutions – became a significant legal problem. By way of illustration, the recognition – against the period of exercising transmission easement – of the period required for the acquisition thereof by adverse possession, whereby before 3 August 2008 the real estate featured the legal state corresponding to the content of this right, is debatable. One cannot recognise that within that period a transmission easement was exercised, because such a right was not in existence as yet. Therefore, the institution that might be employed is the running of the period as regards the adverse possession in relation to an easement appurtenant with the content of a transmission easement. Still, the problem remains as to whether the period of the exercise of the easement appurtenant with the content corresponding to a transmission easement can be recognised against the period of possession required for the adverse possession of a transmission easement pursuant to the regulations introduced in 2008. One might incline to the position whereby in such a case it would be right to fully recognise – against the period of exercising a transmission easement – the period of exercising an easement appurtenant corresponding thereto in respect of its content. That being so, the adverse possession of a transmission easement might ensue in such a situation on 3 August 2008 at the earliest, that is the moment the regulations governing this right come into effect. Conversely, if the prescriptive period expires before that date, the entrepreneur would acquire an easement appurtenant with the content corresponding to the transmission easement. Such an interpretation is aligned with the purpose intended by the legislator, which is to bring order to the actual state of the broadest scope with the aid of a new legal instrument. The text, while analysing the issue of a transmission easement and an adverse possession thereof as a institution of the civil law, presents only some selected problems. Hence, the analysis does not include, for example, the issues concerned with claims for remuneration (for usufruct without contractual basis or usufruct fees), or claims for compensation (redress or amends). Furthermore, the text does not conduct a more profound analysis of the relation between the provisions regulating public-law relations (e.g. acts of law introducing the institution of dispossession) and the provisions regulating civil-law relations (the easements in question).

Characterization of Copper Covetic Bulk and Films: Copper with High Carbon Content

Incorporation of carbon nanostructures in metals is desirable to combine the strongly bonded electrons in the metal and the free electrons in carbon nanostructures that give rise to high ampacity and high conductivity, respectively. Carbon in copper has the potential to impact industries such as: building construction, power generation and transmission, and microelectronics. This thesis focuses on the structure and properties of bulk and thin films of a new material, Cu covetic, that contains carbon in concentrations up to 16 at.%. X-ray photoelectron spectroscopy (XPS) shows C 1s peak with both sp2 and sp3 bonded C measuring up to 3.5 wt.% (16 at.%). High resolution transmission electron microscopy and electron diffraction of bulk covetic samples show a modulated structure of ≈ 1.6 nm along several crystallographic directions in regions that have high C content suggesting that the carbon incorporates into the copper lattice forming a network. Electron energy loss spectra (EELS) from covetics reveal that the level of graphitization from the source material, activated carbon, is maintained in the covetic structure. Bulk Cu covetics have a slight increase in the lattice constant, as well as <111> texturing, or possibly a different structure, compared to pure Cu. Density functional theory calculations predict bonding between C and Cu at the edges and defects of graphene sheets. The electrical resistivity of bulk covetics first increases and then decreases with increasing C content. Cu covetic films were deposited using e-beam and pulsed laser deposition (PLD) at different temperatures. No copper oxide or any allotropes of carbon are present in the films. The e-beam films show enhanced electrical and optical properties when compared to pure Cu films of the same thickness even though no carbon was detected by XPS or EELS. They also have slightly higher ampacity than Cu metal films. EELS analysis of the C-K-edge in the PLD films indicate that graphitic carbon is transferred from the bulk into the films with uniform carbon distribution. PLD films exhibit flatter and higher transmittance curves and sheet resistance two orders of magnitude lower than e-beam films leading to a high figure of merit as transparent conductors.

Joint Optimization for Social Content Delivery in Wireless Networks

Over the last decade, success of social networks has significantly reshaped how people consume information. Recommendation of contents based on user profiles is well-received. However, as users become dominantly mobile, little is done to consider the impacts of the wireless environment, especially the capacity constraints and changing channel. In this dissertation, we investigate a centralized wireless content delivery system, aiming to optimize overall user experience given the capacity constraints of the wireless networks, by deciding what contents to deliver, when and how. We propose a scheduling framework that incorporates content-based reward and deliverability. Our approach utilizes the broadcast nature of wireless communication and social nature of content, by multicasting and precaching. Results indicate this novel joint optimization approach outperforms existing layered systems that separate recommendation and delivery, especially when the wireless network is operating at maximum capacity. Utilizing limited number of transmission modes, we significantly reduce the complexity of the optimization. We also introduce the design of a hybrid system to handle transmissions for both system recommended contents ('push') and active user requests ('pull'). Further, we extend the joint optimization framework to the wireless infrastructure with multiple base stations. The problem becomes much harder in that there are many more system configurations, including but not limited to power allocation and how resources are shared among the base stations ('out-of-band' in which base stations transmit with dedicated spectrum resources, thus no interference; and 'in-band' in which they share the spectrum and need to mitigate interference). We propose a scalable two-phase scheduling framework: 1) each base station obtains delivery decisions and resource allocation individually; 2) the system consolidates the decisions and allocations, reducing redundant transmissions. Additionally, if the social network applications could provide the predictions of how the social contents disseminate, the wireless networks could schedule the transmissions accordingly and significantly improve the dissemination performance by reducing the delivery delay. We propose a novel method utilizing: 1) hybrid systems to handle active disseminating requests; and 2) predictions of dissemination dynamics from the social network applications. This method could mitigate the performance degradation for content dissemination due to wireless delivery delay. Results indicate that our proposed system design is both efficient and easy to implement.

Platinum–tin/carbon catalysts for ethanol oxidation: Influence of Sn content on the electroactivity and structural characteristics

Carbon-supported Pt–Sn catalysts commonly contain Pt–Sn alloy and/or Pt–Sn bimetallic systems (Sn oxides). Nevertheless, the origin of the promotion effect due to the presence of Sn in the Pt–Sn/C catalyst towards ethanol oxidation in acid media is still under debate and some contradictions. Herein, a series of Ptx–Sny/C catalysts with different atomic ratios are synthesized by a deposition process using formic acid as the reducing agent. Catalysts structure and chemical compositions are investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) and their relationship with catalytic behavior towards ethanol electro-oxidation was established. Geometric structural changes are producing by highest Sn content (Pt1–Sn1/C) promoted the interaction of Pt and Sn forming a solid solution of Pt–Sn alloy phase, whereas, the intermediate and lowest Sn content (Pt2–Sn1/C and Pt3–Sn1/C, respectively) promoted the electronic structure modifications of Pt by Sn addition without the formation of a solid solution. The amount of Sn added affects the physical and chemical characteristics of the bimetallic catalysts as well as reducing the amount of Pt in the catalyst composition and maintaining the electrocatalytic activities at the anode. However, the influence of the Sn oxidation state in Pt–Sn/C catalysts surfaces and the alloy formation between Pt and Sn as well as with the atomic ratio on their catalytic activity towards ethanol oxidation appears minimal. Similar methodologies applied for synthesis of Ptx–Sny/C catalysts with a small change show differences with the results obtained, thus highlighting the importance of the conditions of the preparation method.

An investigation of contact transmission of methicillin-resistant staphylococcus aureus

Hand hygiene is critical in the healthcare setting and it is believed that methicillin-resistant Staphylococcus aureus (MRSA), for example, is transmitted from patient to patient largely via the hands of health professionals. A study has been carried out at a large teaching hospital to estimate how often the gloves of a healthcare worker are contaminated with MRSA after contact with a colonized patient. The effectiveness of handwashing procedures to decontaminate the health professionals' hands was also investigated, together with how well different healthcare professional groups complied with handwashing procedures. The study showed that about 17% (9–25%) of contacts between a healthcare worker and a MRSA-colonized patient results in transmission of MRSA from a patient to the gloves of a healthcare worker. Different health professional groups have different rates of compliance with infection control procedures. Non-contact staff (cleaners, food services) had the shortest handwashing times. In this study, glove use compliance rates were 75% or above in all healthcare worker groups except doctors whose compliance was only 27%.