Tars: Timeliness-aware Adaptive Replica Selection for Key-Value Stores

In current large-scale distributed key-value stores, a single end-user request may lead to key-value access across tens or hundreds of servers. The tail latency of these key-value accesses is crucial to the user experience and greatly impacts the revenue. To cut the tail latency, it is crucial for clients to choose the fastest replica server as much as possible for the service of each key-value access. Aware of the challenges on the time varying performance across servers and the herd behaviors, an adaptive replica selection scheme C3 is proposed recently. In C3, feedback from individual servers is brought into replica ranking to reflect the time-varying performance of servers, and the distributed rate control and backpressure mechanism is invented. Despite of C3's good performance, we reveal the timeliness issue of C3, which has large impacts on both the replica ranking and the rate control, and propose the Tars (timeliness-aware adaptive replica selection) scheme. Following the same framework as C3, Tars improves the replica ranking by taking the timeliness of the feedback information into consideration, as well as revises the rate control of C3. Simulation results confirm that Tars outperforms C3.Comment: 10pages,submitted to ICDCS 201

A Green Antisolvent Strategy for Enhancing the Performance of Carbon-based CsPbIBr2 Solar Cells

All-inorganic CsPbIBr2 perovskite materials demonstrated to own a balanceable feature for its acceptable bandgap, good phase stability and excellent thermal stability. Herein, we introduce ethyl acetate (EA) and chlorobenzene (CB) as antisolvent to improve the quality of CsPbIBr2 thin films. Compared with CB, EA is a good green antisolvent, and high-quality CsPbIBr2 thin films with enlarged grain sizes, few grain boundaries as well as improved optical properties were obtained by optimizing EA as antisolvent. Based on a carbon-based and hole-free planar heterojunction structure of FTO/TiO2/CsPbIBr2/Carbon, an optimal power conversion efficiency (PCE) of 4.35% was achieved, 10% enhancement in PCE. This work contributes to selecting nontoxic solvent engineering for realizing the preparation of high-quality CsPbIBr2 thin films and the improved performance of all-inorganic CsPbIBr2 PSCs

Dual-Core Photonic Crystal Fiber for Use in Fiber Filters

An asymmetrical dual-core photonic crystal fiber (DC-PCF), which possesses all circular air holes, is proposed. By setting appropriate geometrical parameters, the wavelength-selective coupling property is realized, and a compact optical filter with a short length of 1.83 mm based on the DC-PCF is designed. The spectral transmission characteristics of the filter are investigated by the beam propagation method. The results demonstrate that the optical filter possesses a bandwidth of ∼ 58 nm and small sidelobes. The proposed optical filter could be used in the integrated optical systems

A Simplified Latent Semantic Indexing Approach for Multi-Linguistic Information Retrieval

Latent Semantic Indexing (LSI) approach provides a promising solution to overcome the language barrier between queries and documents, but unfortunately the high dimensions of the training matrix is computationally prohibitive for its key step of Singular Value Decomposition (SVD). Based on the semantic parallelism of the multi-linguistic training corpus we prove in this paper that, theoretically if the training term-by-document matrix can appear in either of two symmetry forms, strong or weak, the dimension of the matrix under decomposition can be reduced to the size of a monolingual matrix. The retrieval accuracy will not deteriorate in such a simplification. And we also discuss what these two forms of symmetry mean in the context of multi-linguistic information retrieval. Although in real world data the term-by-document matrices are not naturally in either symmetry form, we suggest a way to make them appear more symmetric in the strong form by means of word clustering and term weighting. A real data experiment is also given to support our method of simplification.

An Analysis of Adopting Social Media Marketing to Distribute Independent Films in the UK

With the development of Internet and technology, independent film can be distributed in various methods even with low expenses. Social media could be considered as one of the leading ways of distributing independent films. This dissertation focuses on providing a deeper understanding of how social media has changed the way distributors develop marketing strategies for independent films. Semi-structured interview was used to conduct this research. This research gives distributors the most useful marketing mix and social media platforms for distributing independent films

Flow cytometric analysis of CK19 expression in the peripheral blood of breast carcinoma patients: relevance for circulating tumor cell detection

<p>Abstract</p> <p>Background</p> <p>Immunocytochemistry and RT-PCR have been widely used for the detection of circulating tumor cells in patients with breast cancer but their specificity is limited. Our purpose is to utilize a convenient and specific technology to detect circulating tumor cells in breast cancer patients.</p> <p>Methods</p> <p>To determine the sensitivity and specificity of our method, A431 cells were serially diluted with human peripheral blood leukocytes and stained with CK19. A total of 73 blood specimens including 25 healthy volunteers and 48 patients with breast carcinoma and benign tumor were tested by flow cytometry to quantify the expression of CK19.</p> <p>Results</p> <p>The detectable upper limit of A431 cells was 1 cancer cell among 10⁴human white blood cells. CK19 was detected in 27% of breast cancer patients but none control gives positive result. The number of cancer cells increased gradually along with the disease stages for it was the least in stage I (0%) and the most in stage IV (1.29%). Fifteen patients were observed during three month chemotherapy after surgery, and most of their CK19 expression levels declined after treatment.</p> <p>Conclusion</p> <p>Our research convinces that the detection of CK19 in peripheral blood by flow cytometry is also a specific and feasible method to monitor circulating tumor cells in breast cancer.</p

Regional Climate Effects of Conversion from Grassland to Forestland in Southeastern China

The land-use and land-cover change (LUCC) is the synthetic result of natural processes and human activities; it largely depends on the surface vegetation conditions, and the mutual conversion among land cover types can accelerate or alleviate the regional and global climate changes. Aiming at analyzing the regional climatic effects of the conversion from grassland to forestland, especially in the long term perspective, we carried out the comparison simulation using the Weather Research and Forecasting (WRF) Model in Fujian province, results indicated that this conversion had a significant influence on the regional climate; the annual average temperature decreased by 0.11°C and the annual average precipitation increased by 46 mm after 11.2% of the grassland was converted into the forestland in the study area from 2000 to 2008. In the future (form 2010 to 2050), the conversion from grassland to forestland is significant under two representative concentration pathways (RCPs) (RCP6 and RCP8.5); the spatial pattern of this conversion under the two scenarios is simulated by dynamic of land system (DLS); then, the regional climate effects of the conversion are simulated using WRF model