This paper presents a novel algorithm for vascular tree segmentation based on shortest path connection. The connected vascular tree provides topological features that are instrumental in image-aided ...diagnosis. The proposed method can enforce the connectivity as well as remove the false detection at same time. Multi-scale ridge detector is employed that can locate vessels with different widths. To connect the isolated ridge, the single-source shortest path algorithm is tailored that searches the optimal path. The path metric is defined in terms of probability of pixel belong to foreground and background. This mechanism enables that the false detection could be removed via hypothesis testing. The topological vascular tree with 1-pixel width and fully-connection is segmented from the retinal image. The simplicity and efficiency of the proposed method make it practical to be employed in image-aided diagnosis system readily.
Fibrin deposition was universal in the lungs of SARS patients and fgl2 prothrombinase gene, a novel procoagulant, was demonstrated to express highly in a clinically relevant SARS model. To ...investigate whether and which structural protein of SARS-CoV induced transcription of hfgl2 prothrombinase gene, three eukaryotic expression plasmids expressing nucleocapsid protein (N), membrane protein (M) and spike protein 2 (S2) of SARS-CoV were co-transfected with hfgl2 promoter luciferase-reporter plasmids and β-galactosidase plasmid in CHO cells, respectively. M, N and S2 protein of SARS-CoV were detected by western blotting and immunohistochemistry analysis. Further assays demonstrated that expression of hfgl2 gene was related with N protein, but not with M or S2 protein in THP-1 cells and Vero cells. N protein significantly induced functional procoagulant activity in comparison with control group. Luciferase assay showed that N protein of SARS-CoV could activate the transcription of hfgl2 promoter compared with the pcDNA3.1 empty vector. Site-directed mutagenesis and EMSA assay further demonstrated that transcription factor C/EBP alpha band with its cognate cis-element in hfgl2 promoter. The results showed that N protein of SARS-CoV induced hfgl2 gene transcription dependent on the transcription factor C/EBP alpha, which maybe contribute to the development of thrombosis in SARS.
Sn-Bi solder alloys have been widely used in electronic devices due to its low melting point, low thermal expansion coefficient and good mechanical properties. However, due to the brittleness of Bi ...element in SnBi solder, Bi phase is easy to be vulgar at high temperature, which leads to poor plasticity and ductility of solder joint, which affects the reliability of solder joint in high temperature service. The results show that the wettability, tensile strength and ductility of Sn58Bi solder can be improved when the content of Er is 0.1%. In this paper, Sn58Bi-0.1Er was used as the base metal, and the effects of Ni-CNTs particle reinforced phase on the melting characteristics, mechanical properties, microstructure and composition of the solder were discussed. The results of XRD shows that with the addition of Ni-CNTs, Ni element reacts with Sn to form Ni3Sn4 intermetallic compound, while carbon nanotubes still exist in the form of carbon element. The increase of Ni-CNTs particles can reduce the dendrite structure and refine the microstructure of the composite solder. The addition of Ni-CNTs increased the melting temperature of the composite solder. The tensile test results shows that with the increase of Ni-CNTs particles, the tensile strength and elongation of the composite solder increase first and then decrease. When the content of Ni-CNTs particles is 0.03%, the elongation of composite solder is 82.06%, which is 43% higher than that of Sn58Bi-0.1Er.
Colocating latency-critical (LC) jobs and best-effort (BE) jobs on a host effectively improve resource efficiency in modern datacenters. But it increases resource contention between jobs, which ...seriously affects job performance. In Alibaba's real- world LC- BE colocation datacenters, we observed that cache is one of the most contended resources in the CPU. When cache contention occurs, identifying the antagonists that caused cache resource contention is the first step to mitigate cache contention, called cache antagonists identification (CAl). However, it is chal-lenging to identify cache antagonists because cache contention is difficult to observe and quantify. In this paper, we first propose cache usage graph (CUG) to finely characterize cache usage of jobs in the multiple CPU microarchitectural hierarchies and locations, and we provide a monitoring tool to collect "per-container-per-logic CPU" Ll/2/3 cache misses and build CUG. Then we propose a CUG-based CAl approach, \mu Tactic. \mu Tactic leverages machine learning models to quantify the cache contention on every cache hierarchy, then reasons out the cache antagonists with CUG. Experiments in production datacenters show that \mu Tactic has a high precision (85+%) and low cost (32 ms), which are better than state-of-the-art approaches.
Sn-58Bi-0.1Er solder alloys with different Ni-CNTs contents were prepared by vacuum melting, the influence of Ni-CNTs content on the wetting properties of Sn-58Bi-0.1Er solder was studied. The ...interface morphology of IMC at Sn-58Bi-0.1Er/Cu joint and the creep resistance of Sn-58Bi-0.1Er/Cu joints with different contents of Ni-CNTs were analyzed. The results showed that when added 0.01~0.05 wt% Ni-CNTs, it enhanced the wettability of composite solder alloy on Cu plate, and the inter metallic compound of Sn58Bi/Cu interface changed from sawtooth Cu6Sn5 to thin layer (Cu, Ni)6Sn5. With the increase amount of Ni-CNTs enhanced particles, it can effectively reduce the thickness of IMC layer at the Sn58Bi-0.1Er/Cu interface. By adding Ni-CNTs particles, the creep fracture life of Sn58Bi-0.1Er/Cu joints was greatly improved. The creep fracture life of the joint was the longest when 0.03 wt%Ni-CNTsadded, which was 25650s. The addition of Ni-CNTs reinforcement particles effectively improved the mechanical properties of the Sn58Bi joint.
In this study, the influence of thicknesses of the interlayers on the stress-strain state in the nodes with soft interlayer was investigated by computer simulation. To establish the general patterns ...of SSS formation when loading cylindrical nodes with interlayers of soft rigidity and checking the adequacy of the simulation, thickness of interlayer (0.01,0.03,0.05,0.08mm) with a small TCLE was calculated. The results show that when the thickness of the interlayer changes, the dimensions of this zone vary in direct proportion only. The length from the outer surface of the assembly in the base material at all thicknesses is about 5 times the thickness of the interlayer. Outside this zone, the radial, axial and tangential stresses in the base metal become negligibly small. The interlayer material is in the volumetric stress state throughout its entire length. This provides reliability guidance for the theory of TLP diffusion welding under large gap.
The influences of Er element on microstructure and properties of Sn58Bi based lead-free solder were investigated in this study. With Er element addition, the amount of primary Sn-rich phase increased ...in the Sn-Bi alloys. Sn-58Bi-xEr solder alloy not only is mainly composed of ß-Sn phase and Bi phase, also has trace Er phase, the added rare earth Er does not react with the Sn, Bi to form compounds. Tensile test results showed that the tensile strength changed slightly with increasing Er addition, while the elongation increased remarkably first and then decreased after adding 0.1% Er. With the addition of rare earth element Er, the Cu6Sn5 intermetallic compound layer formed Sn-58Bi-xEr/Cu the interface of welded joint can be refined, and the intermetallic compound layer tends to be flat. With the increase of Er (>0.5%), the oxidation slag will act as the external nucleation particle, which will promote the nucleation of the interface IMC, and then promote the formation of the IMC.
The diffusion brazd test of IC10 superalloy was carried out by using Russia solder M4 interlayer powder. The wetting quality of the high-temperature alloy was evaluated by the contact angle of ...wetting at various temperatures. The result shows that at the temperature of 1250°C, the contact angles of interlayer powder M4 alloy do not exceed 10°, it has high wettability and spreadability over the surface of the IC10 alloy. The structure of the joints has a smooth transition from the base metal to the soldered joint when the interlayer powder M4 was used. In the structure of the joint, the base metal contains a large number of Ɣ '- phases. The microstructure of the weld metal does not have continuous eutectic layers, but includes carbide carboride and other phases when the interlayer powder M4 was used.
In this paper, a novel image thresholding based on Two-Dimensional Arimoto Entropy (TDAE), called Ellipsoid Region Search Strategy (ERSS), is proposed. The basic idea is to search the optimal ...threshold from the reference point obtained by one-dimensional OTSU algorithm. Different from existing approaches, our approach provides a scheme to reduce the number of samples through the existing relatively easy and efficient algorithm. Additionally, this approach improves the performance of image segmentation. The experimental results on image segmentation demonstrate that our method is not only significantly more efficient but also accelerates the computation speed of two-dimensional Arimoto entropic thresholding algorithms.
Service search has been introduced to exploit heterogeneous resources of distributed devices on the purpose of supplying ubiquitous services in ubiquitous stub environments, especially in MANETs. ...However, due to the characteristics of infrastructure-less, devices' limited resources, and dynamic topology caused by the mobility of devices, service search faces great risk of failure. Usually, clusters are the main way of organizing the devices in MANETs. Therefore, an effective clustering algorithm is necessary to ensure the reliability of service search. A maximized reliability clustering algorithm (MRCA) is proposed. We present predicted battery supporting time, CPU computing power, connecting degree and predicted velocity of devices, select the best devices as cluster heads. We combine the four factors together using FAHP algorithm. The simulations show that the MRCA can prolong cluster headers and members' valid time, reduce the consumed energy in the cluster's life cycle. This proves that MRCA can improve the reliability of cluster.
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