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Distribution of time-bin qubits over 50 km of optical fiber  [PDF]
I. Marcikic,H. de Riedmatten,W. Tittel,H. Zbinden,M. Legre,N. Gisin
Physics , 2004, DOI: 10.1103/PhysRevLett.93.180502
Abstract: We report experimental distribution of time-bin entangled qubits over 50 km of optical fibers. Using actively stabilized preparation and measurement devices we demonstrate violation of the CHSH Bell inequality by more than 15 standard deviations without removing the detector noise. In addition we report a proof of principle experiment of quantum key distribution over 50 km of optical fibers using entangled photon.
THE CONTENT OF HEAVY METALS IN POLLEN FROM DAMBOVITA REGION  [PDF]
ION V. POPESCU,GABRIEL DIMA,SERGIU DINU
Journal of Science and Arts , 2010,
Abstract: The purpose of the study is to evaluate the use of the pollen as bio-indicator of environmental pollution. The content in Fe, Mn, and Zn from pollen samples uniformly distributed in Dambovita region was determined. We have collected samples during April 2009 from 18 bee houses from private farms, kipped in industrial-urban and non industrial-rural areas. The samples were analyzed with an Elvax ED-XRF spectrometer having a solid state Si-pin-diode detector with thermo-electrical cooling with 165 eV at 5.9 keV (Fe55 isotope) energy resolution. We found differences between the two kinds of samples and we concluded that the pollen can be used for bio-monitoring of environment for Fe, Mn, and Zn.
Unconditionally secure quantum key distribution over 50km of standard telecom fibre  [PDF]
C. Gobby,Z. L. Yuan,A. J. Shields
Physics , 2004, DOI: 10.1049/el:20045038
Abstract: We demonstrate a weak pulse quantum key distribution system using the BB84 protocol which is secure against all individual attacks, including photon number splitting. By carefully controlling the weak pulse intensity we demonstrate the maximum secure bit rate as a function of the fibre length. Unconditionally secure keys can be formed for standard telecom fibres exceeding 50 km in length.
Statistical Properties of Molecular Clumps in the Galactic Center 50 km s$^{-1}$ Molecular Cloud  [PDF]
Masato Tsuboi,Atsushi Miyazaki
Physics , 2012, DOI: 10.1093/pasj/64.5.111
Abstract: We present the statistical properties of molecular clumps in the Galactic center 50 km s$^{-1}$ molecular cloud (GCM-0.02-0.07) based on observations of the CS $J=1-0$ emission line with the Nobeyama Millimeter Array. In the cloud, 37 molecular clumps with local thermal equilibrium (LTE) masses of $2\times10^2-6\times10^3 M_\odot$ were identified by using the {\it clumpfind} algorithm. The velocity widths of the molecular clumps are about five-fold those of Galactic disk molecular clouds with the same radius. The virial-theorem masses are three-fold the LTE masses. The mass and size spectra can be described by power laws of $dN/dM\propto M^{-2.6\pm0.1}$ ($M\gtrsim 900M_\odot$) and $dN/dR\propto R^{-5.9\pm0.3}$ ($R\gtrsim 0.35$ pc), respectively. The statistical properties of the region interacting with the Sgr A East shell and those of the non-interacting part of the cloud are significantly different. The interaction probably makes the mass function steeper, from $dN/dM\propto M^{-2.0\pm0.1}$ in the non-interacting part to $dN/dM\propto M^{-4.0\pm0.2}$ in the interacting region. On the other hand, the interaction presumably truncates the size spectrum on the larger side of $R\sim 0.4$ pc.
Cloud-cloud Collision in the Galactic Center 50 km s$^{-1}$ Molecular Cloud  [PDF]
Masato Tsuboi,Atsushi Miyazaki,Kenta Uehara
Physics , 2015, DOI: 10.1093/pasj/psv076
Abstract: We performed a search of star-forming sites influenced by external factors, such as SNRs, HII regions, and cloud-cloud collisions, to understand the star-forming activity in the Galactic center region using the NRO Galactic Center Survey in SiO $v=0, J=2-1$, H$^{13}$CO$^+ J=1-0$, and CS $J=1-0$ emission lines obtained by the Nobeyama 45-m telescope. We found a half-shell like feature (HSF) with a high integrated line intensity ratio of $ int T_{ mathrm B}$(SiO $v=0, J=2-1$)$dv$/$ int T_{ mathrm B}$(H$^{13}$CO$^+ J=1-0$)$dv sim6-8$ in the 50 km s$^{-1}$ molecular cloud, which is a most conspicuous molecular cloud in the region and harbors an active star-forming site seen as several compact HII regions. The high ratio in the HSF indicates that the cloud contains huge shocked molecular gas. The HSF is also seen as a half-shell feature in the position-velocity diagram. A hypothesis explaining the chemical and kinetic properties of the HSF is that the feature is originated by a cloud-cloud collision (CCC). We analyzed the CS $J=1-0$ emission line data obtained by Nobeyama Millimeter Array to reveal the relation between the HSF and the molecular cloud cores in the cloud. We made a cumulative core mass function (CMF) of the molecular cloud cores within the HSF. The CMF in the CCC region is not truncated at least up to $ sim2500M_ odot$ although the CMF of the non-CCC region reaches the upper limit of $ sim1500M_ odot$. Most massive molecular cores with $M_{ mathrm{gas}}>750 M_{ odot}$ are located only around the ridge of the HSF and adjoin the compact HII region. These may be a sign of massive star formation induced by CCC in the Galactic center region.
全球50km分辨率snu-agcm模式模拟热带气旋活动  [PDF]
曹翔?,吴立广?,曹剑?
气象科学 , 2015, DOI: 10.3969/2014jms.0050
Abstract: 为了验证50km分辨率的snu-agcm模式(seoulnationaluniversityatmosphericgeneralcirculationmodel)模拟tc活动的能力,利用hadley中心月平均海温资料驱动模式,模拟了1980—2009年全球热带气旋的活动特征。与观测资料对比分析,两组利用不同对流参数化方案的试验,都能够模拟与观测类似的tc结构以及全球tc活动的主要特点,包括全球生成总频数、各海区路径分布和tc活动的季节变化。但是各个海域tc生成的年平均频数与观测还存在明显差异。模式中西北太平洋和南太平洋两组试验平均的tc频数较观测分别偏多21.5%和31.3%;而北大西洋、南北印度洋分别偏少11.4%、41.1%和50%。模拟的东北太平洋tc比观测少了将近88%,而观测中tc极少的南大西洋在两组试验中平均每年却有1.5个tc生成。模拟的tc频数较观测的差异主要与模拟的北印度洋季风、西北太平洋季风槽、垂直风切变、850hpa相对涡度与观测的差异有关。
Assessment of ecological protection importance for ecological conservation in Wenchuan Earthquake hard-hit disaster areas
汶川地震重灾区生态保护重要性评价与对策

Xu Weihua,
徐卫华
,欧阳志云,王学志,王文杰,董仁才,白杨

生态学报 , 2008,
Abstract: Assessment of ecological protection importance and identification of important area for ecological protection is the basis for restoration and construction in earthquake hard-hit area. In this study, ecological protection importance in 51 counties of hard-bit disaster area was assessed based on previous research and three indicators including soil erosion sensitivity, biodiversity conservation importance, and water conservation importance. Results showed that highly important areas for ecological protection made up 26.7% of the total area of this region, with the total area of 35 thousands of km2. They were mainly distributed in Wenchuan and Siguanniang mountain in north Qionglai Mountains, and large area of Minshan Mountains. Important areas were mainly distributed in west and northeast of this region with the total area of 46 thousands of km2, accounting for 34.5% of the total area of the entire region. Measures including strict protection, ban of large scale of development and construction activities, and population control, should be taken in highly important areas. In important areas, development activities should be also restricted. These measures, together with ecological compensation and ongoing ecological engineering including Natural Forestry Conservation, Grain to Green, and Comprehensive Watershed Management, will facilitate the restoration of ecological services in this region.
The good will
Babi? Jovan
Theoria, Beograd , 2007, DOI: 10.2298/theo0704007b
Abstract: Kant begins his most important ethical writing, Groundwork of the metaphysics of morals, with a very strong statement that 'it is impossible to think of anything at all in the world, or indeed beyond it, that could be considered good without limitation except a good will'. Other goods, or good features of human nature and the benefits of a good life, are good only under some proper conditions, the most important of which is precisely the good will. It is the capacity of autonomy, and entirely independent of all external ('empirical') conditions, and such a capacity is present in every moral agent capable to act 'from the duty', i. e. on the basis that morality could be the sole reason for doing what is right. So, good will is the ground of morality, and an expression of the presence of the personal autonomy.
The Importance of Knowledge Management and Trust in Relation to Disaster Response  [cached]
Nicole Tanner
Dalhousie Journal of Interdisciplinary Management , 2010, DOI: 10.5931/djim.v6i1.39
Abstract: This article investigates the importance of Knowledge Management (KM) and trust in disaster response. In KM, a lack of trust and non-reciprocity of information can hinder the process of knowledge transfer. Similarly, a lack of KM coinciding with a disaster can lead to public distrust of those in positions of authority. In the Exxon Valdez oil spill disaster, many people were impacted by issues of trust related to the transfer of knowledge and improper KM. However, mistrust due to poor KM is not unique to the Exxon Valdez spill. This article also discusses other disaster scenarios, such as the aftermath of Hurricane Katrina and the Central Natural Gas Corporation?s business disaster, which were both exacerbated by poor KM and breaks in the knowledge transfer process.
50 GHz Spaced 4 × 40 Gbit/s WDM Transmission over 700 km Using 6 ps Bandlimited RZ Signals  [PDF]
Mousaab M. Nahas
Optics and Photonics Journal (OPJ) , 2011, DOI: 10.4236/opj.2011.13023
Abstract: In this paper, we present 50 GHz spaced 4 ×40 Gbit/s WDM transmission over 700 km using SMF-based Effective Area Enlarged Positive Dispersion Fiber in a recirculating loop. The paper uses bandlimited RZ signals and shows that transmission distance of 700 km can be achieved with BER ≤ 10-9 using 6 ps pulsewidth for each data signal. To attain this, optical filters with sharp transmission characteristics are used in both transmitter and receiver. The results demonstrated in this paper are based on simulation, and the author believes the propagation distance reached in the paper is the longest distance achieved for such system.
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