Sensor placement in the noise source identification based on acoustic radiation modes

The noise source identification technology based on acoustic radiation modes could identify the noise source under less measuring points, while the sensor placement has great influence on the result of noise source identification. Under the prescribed number of sensors, a method to configure the measuring points is proposed. By the means of successive removal, select a set of measuring points in the candidate field points, which make the orthogonality of the acoustic field distribution modes matrix achieve the maximum value. The results of numerical simulation and sound box experiment have shown that when sensors are arranged in accordance with the measuring points selected by this method, the noise source could be identified effectively, and the identification result is better than that when sensors are arranged evenly

Topological optimization of hybrid quantum key distribution networks

With the growing complexity of quantum key distribution (QKD) network structures, aforehand topology design is of great significance to support a large-number of nodes over a large-spatial area. However, the exclusivity of quantum channels, the limitation of key generation capabilities, the variety of QKD protocols and the necessity of untrusted-relay selection, make the optimal topology design a very complicated task. In this research, a hybrid QKD network is studied for the first time from the perspective of topology, by analyzing the topological differences of various QKD protocols. In addition, to make full use of hybrid networking, an analytical model for optimal topology calculation is proposed, to reach the goal of best secure communication service by optimizing the deployment of various QKD devices and the selection of untrusted-relays under a given cost limit. Plentiful simulation results show that hybrid networking and untrusted-relay selection can bring great performance advantages, and then the universality and effectiveness of the proposed analytical model are verified.Comment: 12 pages, 4 figure

The impact of international codes of conduct on employment conditions and gender issues in Chinese flower companies

The study examined how international codes of conduct address employment conditions and gender issues in the Chinese flower industry. A sample of 20 companies was purposively selected and 200 workers from these companies were interviewed. The adoption of international codes did not improve workers conditions and gender issues and codes were poorly enforced. There was evidence of discrimination based on workers’ status of employment and gender. A permanent worker mean daily wage was RMB14.1 higher than a casual worker. Although welfare benefits were provided to permanent workers, males and females beneficiaries differed significantly by 32.4 and 24.1%, respectively. This paper provided the basis for the need to gender audit, mainstream flower companies and adopts participatory auditing for flower companies’ compliance to the use of codes of conduct.Key words: Codes of conduct, Chinese flower industry, mainstream, gender, permanent worker, casual worker, employment conditions

A simulation study on the measurement of D0-D0bar mixing parameter y at BES-III

We established a method on measuring the \dzdzb mixing parameter $y$ for BESIII experiment at the BEPCII $e^+e^-$ collider. In this method, the doubly tagged $\psi(3770) \to D^0 \overline{D^0}$ events, with one $D$ decays to CP-eigenstates and the other $D$ decays semileptonically, are used to reconstruct the signals. Since this analysis requires good $e/\pi$ separation, a likelihood approach, which combines the $dE/dx$, time of flight and the electromagnetic shower detectors information, is used for particle identification. We estimate the sensitivity of the measurement of $y$ to be 0.007 based on a $20fb^{-1}$ fully simulated MC sample.Comment: 6 pages, 7 figure

Measurements of the observed cross sections for exclusive light hadron production in e^+e^- annihilation at \sqrt{s}= 3.773 and 3.650 GeV

By analyzing the data sets of 17.3 pb$^{-1}$ taken at $\sqrt{s}=3.773$ GeV and 6.5 pb$^{-1}$ taken at $\sqrt{s}=3.650$ GeV with the BESII detector at the BEPC collider, we have measured the observed cross sections for 12 exclusive light hadron final states produced in $e^+e^-$ annihilation at the two energy points. We have also set the upper limits on the observed cross sections and the branching fractions for $\psi(3770)$ decay to these final states at 90% C.L.Comment: 8 pages, 5 figur

Surgical outcomes of hepatocellular carcinoma with extrahepatic bile duct tumor thrombus: a multicenter study

BackgroundThe long-term prognosis after surgery of patients with hepatocellular carcinoma (HCC) and extrahepatic bile duct tumor thrombus (Ex-BDTT) remains unknown. We aimed to identify the surgical outcomes of patients with HCC and Ex-BDTT.MethodsA total of 138 patients with Ex-BDTT who underwent hepatectomy with preservation of the extrahepatic bile duct from five large hospitals in China between January 2009 and December 2017 were included. The Cox proportional hazards model was used to analyze overall survival (OS) and recurrence-free survival (RFS).ResultsWith a median follow-up of 60 months (range, 1–127.8 months), the median OS and RFS of the patients were 28.6 and 8.9 months, respectively. The 1-, 3-, and 5-year OS rates of HCC patients with Ex-BDTT were 71.7%, 41.2%, and 33.5%, respectively, and the corresponding RFS rates were 43.5%, 21.7%, and 20.0%, respectively. Multivariate analysis identified that major hepatectomy, R0 resection, and major vascular invasion were independent prognostic factors for OS and RFS. In addition, preoperative serum total bilirubin ≥ 4.2 mg/dL was an independent prognostic factor for RFS.ConclusionMajor hepatectomy with preservation of the extrahepatic bile duct can provide favorable long-term survival for HCC patients with Ex-BDTT

Physics at BES-III

This physics book provides detailed discussions on important topics in $\tau$-charm physics that will be explored during the next few years at \bes3 . Both theoretical and experimental issues are covered, including extensive reviews of recent theoretical developments and experimental techniques. Among the subjects covered are: innovations in Partial Wave Analysis (PWA), theoretical and experimental techniques for Dalitz-plot analyses, analysis tools to extract absolute branching fractions and measurements of decay constants, form factors, and CP-violation and \DzDzb-oscillation parameters. Programs of QCD studies and near-threshold tau-lepton physics measurements are also discussed.Comment: Edited by Kuang-Ta Chao and Yi-Fang Wan

Measurements of the observed cross sections for e+e−→e^+e^-\to exclusive light hadrons containing π0π0\pi^0\pi^0 at s=3.773\sqrt s= 3.773, 3.650 and 3.6648 GeV

By analyzing the data sets of 17.3, 6.5 and 1.0 pb$^{-1}$ taken, respectively, at $\sqrt s= 3.773$, 3.650 and 3.6648 GeV with the BES-II detector at the BEPC collider, we measure the observed cross sections for $e^+e^-\to \pi^+\pi^-\pi^0\pi^0$, $K^+K^-\pi^0\pi^0$, $2(\pi^+\pi^-\pi^0)$, $K^+K^-\pi^+\pi^-\pi^0\pi^0$ and $3(\pi^+\pi^-)\pi^0\pi^0$ at the three energy points. Based on these cross sections we set the upper limits on the observed cross sections and the branching fractions for $\psi(3770)$ decay into these final states at 90% C.L..Comment: 7 pages, 2 figure