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71.
Abdullah Al-Hadi Azremi Janne Ilvonen Risto Valkonen Jari Holopainen Outi Kivekäs Clemens Icheln Pertti Vainikainen 《International Journal of Wireless Information Networks》2011,18(3):146-157
This paper presents a comprehensive simulation study on the performance of coupling element-based dual-antenna structures
on a mobile terminal at the 2,000 MHz Universal Mobile Telecommunications System (UMTS) frequency band with varying two significant
hand effects; vertical position of hand along terminal chassis, and distance between hand palm and terminal chassis. The results
reveal that in uniformly distributed isotropic environment, there exists a gain imbalance between antenna elements due to
hand effects and it is shown that a gain imbalance of 3.7 dB lead to a reduction of 1.9 dB in diversity gain at 99% reliability
level using maximal ratio combining (MRC) technique. For a dual-antenna configuration, the impact of gain imbalance on diversity
gain is more significant when only one antenna element is in close proximity to the hand, compared to when both antenna elements
are in the presence of the hand. It is also shown that a dual-antenna structure with elements vertically oriented along the
edges of a small 100 mm × 40 mm mobile terminal chassis achieves better performance in port-to-port isolation, gain imbalance
and diversity gain compared to other studied dual-antenna configurations when the user’s hand is present. 相似文献
72.
Anja Keskinarkaus Sami Huttunen Antti Siipo Jukka Holappa Magda Laszlo Ilkka Juuso Eero Väyrynen Janne Heikkilä Matti Lehtihalmes Tapio Seppänen Seppo Laukka 《Multimedia Tools and Applications》2016,75(11):6321-6345
The MORE system is designed for observation and machine-aided analysis of social interaction in real life situations, such as classroom teaching scenarios and business meetings. The system utilizes a multichannel approach to collect data whereby multiple streams of data in a number of different modalities are obtained from each situation. Typically the system collects a 360-degree video and audio feed from multiple microphones set up in the space. The system includes an advanced server backend component that is capable of performing video processing, feature extraction and archiving operations on behalf of the user. The feature extraction services form a key part of the system and rely on advanced signal analysis techniques, such as speech processing, motion activity detection and facial expression recognition in order to speed up the analysis of large data sets. The provided web interface weaves the multiple streams of information together, utilizes the extracted features as metadata on the audio and video data and lets the user dive into analyzing the recorded events. The objective of the system is to facilitate easy navigation of multimodal data and enable the analysis of the recorded situations for the purposes of, for example, behavioral studies, teacher training and business development. A further unique feature of the system is its low setup overhead and high portability as the lightest MORE setup only requires a laptop computer and the selected set of sensors on site. 相似文献
73.
Janne Olsen Frenvik Solveig Kristensen Olav B. Ryan 《Drug development and industrial pharmacy》2016,42(8):1215-1224
Targeted thorium conjugates are currently being investigated as a new class of alpha-radiopharmaceuticals. The natural decay of thorium-227 (227Th) results in the ingrowth of radium-223 (223Ra). Consideration must, therefore, be given to define acceptable limits of 223Ra in the drug product at the time of dose administration. By effective sequestration of 223Ra, we aim to improve the radiochemical purity and extend the effective user window of drug products containing 227Th. 223Ra is the first progeny of 227Th and the only one with a long half-life (days). We have, therefore, focused on the removal of this specific species since the progenies of 223Ra will have a very limited lifetime in the formulation once 223Ra is removed. In this study, we investigated a multitude of materials for their ability to reduce the 223Ra level by: (1) passive diffusion or (2) by cartridge filtration on gravity columns. In addition, we probe the compatibility of these materials in the presence of antibody trastuzumab to assess the level of protein binding and estimate the quenching of radiolysis by binding of radionuclides. A screening matrix of organic and inorganic materials was established, i.e. strontium and calcium alginate gel beads, distearoyl phosphatidylglycerol (DSPG) liposomes, ceramic hydroxyapatite, Zeolite UOP type 4A and cation exchange resins AG50W-X8 and SOURCE 30S. First, passive diffusional uptake of 223Ra by suspended materials present in the formulation was measured as a decrease in sample radioactivity after separation. Second, selected materials were packed on gravity columns in order to evaluate the efficiency of column separation versus diffusional adsorption. The retention of 223Ra and 227Th were characterized by measuring the radioactivity in the eluate and on the columns. Finally, the compatibility between trastuzumab, as a selected model antibody, and suspensions of the binding materials was analyzed during storage of the drug product in the presence of adsorbent. The formation of H2O2 was evaluated to measure the influence of radionuclide binding material on radiolysis in the formulation. All the materials bound 223Ra by passive diffusional uptake ranging from 31% to 95% with DSPG liposomes demonstrating superiority at 95% efficiency. All materials suitable for assessment by gravity column filtration bound 223Ra almost quantitatively (~100%) and with minimal variation (relative standard deviation <1%). The uptake was significantly higher compared to passive diffusional uptake. Alginate gel beads, ceramic hydroxyapatite and SOURCE 30S reduced the antibody concentration in solution to 40–50% while the Zeolite UOP type 4A, AG50W-X8 resin and DSPG liposomes showed?≤10% reduction of antibody concentration. Ceramic hydroxyapatite significantly reduced H2O2 formed by radionuclide initiated radiolysis. 相似文献
74.
Minna Toivola Lauri Peltokorpi Janne Halme Peter Lund 《Solar Energy Materials & Solar Cells》2007,91(18):1733-1742
The effect of repeated temperature variations on the performance of both fresh and aged dye-sensitized solar cells with liquid and semi-solid electrolytes has been studied. The cell performance was characterized with IV-curves obtained at different cell operating temperatures and electrochemical impedance spectroscopy measurements before and after the temperature treatments. Consecutive temperature rampings of the aged cells did regenerate the cell function, so that the total efficiency drop over the observation period was on average 18%/unit less for the temperature-treated cells than for reference cells aged at constant temperature. 相似文献
75.
Contamination analysis of persistent and nonpersistent Listeria monocytogenes strains in three meat processing plants and one poultry processing plant were performed in order to identify factors predisposing to or sustaining persistent plant contamination. A total of 596 L. monocytogenes isolates were divided into 47 pulsed-field gel electrophoresis (PFGE) types by combining the restriction enzyme patterns of AscI (42 patterns) and ApaI (38 patterns). Persistent and nonpersistent strains were found in all plants. Nonpersistent PFGE types were found mostly at one sampling site, with the processing environment being the most common location, whereas the persistent strains were found at several sampling sites in most cases. The processing machines were frequently contaminated with persistent L. monocytogenes PFGE types, and it was of concern that surfaces having direct contact with the products were contaminated. The role of the processing machines in sustaining contamination and in contaminating the products appeared to be important because the final product of several processing lines was contaminated with the same L. monocytogenes PFGE type as that found in the processing machine. The proportion of persistent PFGE types in heat-treated products was eight times higher than in the raw products, showing the importance of the persistent PFGE types as contaminants of the final heat-treated products. The contamination status of the processing lines and machines appeared to be influenced by the compartmentalization of the processing line, with poor compartmentalization increasing L. monocytogenes contamination. The separation of raw and post-heat treatment areas seemed especially important in the contamination status of post-heat treatment lines. 相似文献
76.
77.
Tuomo Hänninen Janne Janhunen Markku Juntti 《Analog Integrated Circuits and Signal Processing》2014,78(3):645-655
We summarize our recent state-of-the-art programmable and reconfigurable detector and QR decomposition (QRD) implementations targeting 3G long term evolution (LTE) downlink and uplink requirements. The downlink transmission is based on the orthogonal frequency division multiplexing, whereas the uplink transmission uses a single-carrier frequency-division multiple access. The downlink implementations are based on the programmable transport triggered architecture (TTA) which provides a flexible and energy efficient architecture template. In TTA detector implementation, the LTE detection rate requirements up to 20 MHz bandwidth and 4 × 4 antenna system with 64-QAM, are achieved by using 1–6 programmable cores in parallel. Each core runs at 277 MHz clock frequency and consumes 55.5–64.0 mW depending on the detector configuration. The downlink detector is based on the selective spanning with fast enumeration algorithm. The uplink field-programmable gate array (FPGA) detector implementation is targeted for 4 × 4 antenna system and 64-QAM achieving a detection rate requirement for 20 MHz bandwidth. The used FPGA board for uplink implementation is Xilinx Virtex-6 and the implementation has been carried out using Xilinx Vivado high level synthesis tool. Two different detector architectures are implemented. The first one achieves the detection rate requirement with a single processing block running at 231 MHz and the latter one with four blocks in parallel, each running at 247 MHz. The implemented detector is based on the K-best algorithm. A multiple-input multiple-output receiver requires QRD to produce valid inputs for the detector. In addition to detector implementations, QRD is also implemented on both TTA and FPGA. Modified Gram–Schmidt algorithm is used in both QRD implementations. 相似文献
78.
79.
PM H?gg A Muona J Liétard S Kivirikko T Pihlajaniemi 《Canadian Metallurgical Quarterly》1998,273(28):17824-17831
The human gene for the alpha1 chain of type XV collagen (COL15A1) is about 145 kilobases in size and contains 42 exons. The promoter is characterized by the lack of a TATAA motif and the presence of several Sp1 binding sites, some of which appeared to be functional in transfected HeLa cells. Comparison with Col18a1, which encodes the alpha1(XVIII) collagen chain homologous with alpha1(XV), indicates marked structural homology spread throughout the two genes. The mouse Col18a1 contains one exon more than COL15A1, due to the fact that COL15A1 lacks sequences corresponding to exon 3 of Col18a1, which encodes a cysteine-rich sequence motif. Twenty-five of the exons of the two genes are almost identical in size, six of them contain conserved split codons, and the locations of the respective exon-intron junctions are identical or almost identical in the two genes. The homologous exons include the closely adjacent first pair of exons and the exons encoding a thrombospondin-1 homology found in the N-terminal noncollagenous domain 1, which are followed by the most variable part of the two genes, covering the C-terminal half of their noncollagenous domain 1 and the beginning of the collagenous portion, after which most of the exons are homologous. The lengths of the introns are not similar in these genes, with two exceptions, namely the first intron, which is very short, less than 100 base pairs, and the second intron, which is very large, about 50 kilobases, in both genes. It can be concluded that COL15A1 and Col18a1 are derived from a common ancestor. 相似文献
80.
We have designed a sub-critical helium-cooled core with TiN-coated particle fuel, dedicated to the transmutation of minor actinides. The excellent neutronic properties of helium allows for a low plutonium fraction in the fuel, which yields a low reactivity swing, Δk = 2600 pcm, for a burnup of 31.2%. Further the neutron spectrum is hard, limiting the buildup of Cm and Cf. The high burnup combined with a minor actinide burning rate of 355 kg/GWth year makes the present design an attractive transmutation system. 相似文献