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1.
A cable fault location instrument based on the detection of traveling wave currents was developed. It is different from the conventional pulse radar method based on voltage detection. Measurement is automated, and the distance to the fault point is displayed by merely pushing a switch. In a branched or crossbonded line, the fault point can be located without interference from the branched or the crossbonded point. Tests performed in both real and simulated lines confirmed the practical utility of this instrument  相似文献   
2.
Summary A weak logic of programs is a formal system in which statements that mean the program halts cannot be expressed. In order to prove termination, we would usually have to use a stronger logical system. In this paper we show how we can prove termination of both iterative and recursive programs within a weak logic by augmenting the programs with counters and adding bound assertions on the counters as loop invariants and entry conditions. Thus, most of the existing verifiers which are based on a weak logic of programs can be used to prove termination of programs without any modification. We give examples of proofs of termination and of upper bounds on computation time that were obtained using a Pascal program verifier. The use of the method to locate causes of non-termination is also illustrated.This research was supported inpart by the Advanced Research Agency of the Office of the Secretary of Defence under contract DAHC 15-73-C-0435  相似文献   
3.
In the domain of supply chain management (SCM), various software packages have been developed for planning business strategies. To solve the problem of system productivity in applying planning packages, we propose a solution concept, business process integration (BPI), which fuses workflow and enterprise application integration (EAI) technology. Two characteristic policies are included in BPI. The first is to design the minimum set of business processes for real-time information sharing with planning packages without changing other processes. The second is to integrate several systems with EAI technology and to manage their execution with a workflow tool. Based on these policies, we propose various design templates and integration adapters. Our evaluation shows that using BPI, a target system can be developed with less manpower, in less time, and with higher quality than previous methods.  相似文献   
4.
Gastric cancer (GC) is one of the major malignant diseases worldwide, especially in Asia. It is classified into intestinal and diffuse types. While the intestinal-type GC (IGC) is almost certainly caused by Helicobacter pylori (HP) infection, its role in the diffuse-type GC (DGC) appears limited. Recently, genome-wide association studies (GWAS) on Japanese and Chinese populations identified chromosome 1q22 as a GC susceptibility locus which harbors mucin 1 gene (MUC1) encoding a cell membrane-bound mucin protein. MUC1 has been known as an oncogene with an anti-apoptotic function in cancer cells; however, in normal gastric mucosa, it is anticipated that the mucin 1 protein has a role in protecting gastric epithelial cells from a variety of external insults which cause inflammation and carcinogenesis. HP infection is the most definite insult leading to GC, and a protective function of mucin 1 protein has been suggested by studies on Muc1 knocked-out mice.  相似文献   
5.
The modeling of particle aggregation under a simple shear flow and the extension of the model to a stirred vessel is described. The model quantitatively demonstrates the change of the number of aggregates with time for each shear rate. This number increased with higher shear rate and, conversely, the aggregate size became small when raising the shear rate. This was because aggregates were broken by the stronger shear force. The number of aggregates for different impellers was determined. The shear rate was back‐calculated from the experimentally obtained aggregate size and the model equation. This shear rate was different from that estimated from the Metzner‐Otto method, consequently, some revisions of the Metzner‐Otto equation might be necessary for its application to particle aggregation.  相似文献   
6.
An experimental study has been performed to investigate the relationship between the extensional viscosity of polymers and the turbulent drag reduction. Self‐standing flowing soap film was used to generate two‐dimensional (2‐D) turbulent flow to eliminate shear stress. Two types of polymers having different flexibilities were added to the 2‐D turbulence. The effects of these polymers were visualized by the interference pattern of flowing soap films. The vortex deformation by adding polymers was analyzed by Fourier transformation and wavelet transformation. The scaling exponents of the power spectrum of interference patterns indicate that the mechanism of turbulence laminarization due to the extensional viscosity is anisotropic. A wavelet analysis reveals the high and low fluctuations of the polymer‐added flow. Results from wavelet analysis indicate disappearing of original vortices, and appearing of new structures in low frequency in 2‐D flow. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1854–1862, 2014  相似文献   
7.
In this paper, a model estimating the time-dependent distribution of cluster size consisting of fine particles in Newtonian molten polymer was proposed. The present model for agglomerative suspension was developed based on Usui’s thixotropy model, derived by taking the balance between shear breakup, shear coagulation and Brownian coagulation processes. The analysis was applied to the experimental results for silica/(ethylene methyl-meta acrylate copolymer) suspensions. The time variations of cluster size distributions, of viscosities and of the mean numbers of particles in a cluster were calculated and the results were compared with experimental results for the cases of shear rates from 0.2 to 10 s?1 when the solid volume fraction was set at 0.15. From the results, it was found that the present model can estimated the steady state values of the slurry viscosity and the mean particle numbers in a cluster as well as Usui’s original model. However, the model could not sufficiently express the time variation of rheological characteristics due to the over-estimation of the contribution of shear rate when the cluster size is small.  相似文献   
8.
We describe a novel automated flow immunoassay system for quantification of anti-double-stranded (ds) DNA autoimmune antibodies in the serum of patients suffering from systemic lupus erythematosus. dsDNA (360 bp) was covalently coupled with alkaline phosphatase (ALP) to form a novel analytical reagent (ALP-DNA). After immunoreaction, antibody-antigen complexes between ALP-DNA and anti-dsDNA monoclonal antibody were separated from unreacted ALP-DNA by an ion-exchange column on the basis of the difference in isoelectric point. Antibody-antigen complexes were subsequently quantified by luminescence following addition of 3-(2'-spiroadamantane)-4-methoxy-4-(3"-phosphoryloxy)phenyl- 1,2-dioxetane. The assay yielded a linear relationship between signal and concentration of anti-dsDNA monoclonal antibody in the range of 0-300 micrograms/mL. This simple technique permits the assay of anti-dsDNA autoimmune antibodies within 25 min. The ion-exchange column was simply regenerated by occasional elution with eluent (20 mM N-methylpiperazine, pH 5.5) supplemented with 0.5 M NaCl, to remove unreacted ALP-DNA.  相似文献   
9.
To clarify how seroconversion after age 40 years contributes to the seroprevalence of human T lymphotropic virus type I (HTLV-I), Japanese residents were studied in an area of Kyushu in which HTLV-I is endemic. Cross-sectional data showed higher seroprevalences among subjects > or = 40 than in those < 40 years old (27.0% vs. 7.9%). The prevalence was also greater in women than men (25.5% vs. 17.6%). Six hundred subjects > or = 40 years old were tested during 1976-1993. Among 8 who seroconverted, 5 had an HTLV-seropositive spouse and 2 seroconverted after blood transfusions. The incidences per 1000 person-years of seroconversion in age groups 40-49, 50-59, and > or = 60 years were, respectively, 0.0, 0.0, and 3.3 (range, 1.38-5.13) in men and 0.0, 5.3 (range, 0.11-7.99), and 1.4 (range, 0.00-1.60) in women. The seroconversion incidence was insufficient to account for the rise of seroprevalence in those > or = 40 years old, especially among women. These results suggest that the high rate and sex discordance in HTLV-I seroprevalence after age 40 may depend mainly on the birth cohort effect for vertical or horizontal transmission.  相似文献   
10.
Abstract— A polymerizable liquid crystal (PLC), the orientation of which can be frozen, is useful for making retardation layers. In this paper, a new color filter (CF) with retardation‐controlling layers made of PLC is reported. It has a positive A‐plate and a negative C‐plate, both directly stacked on a color‐filter layer. These two retardation layers exhibit good orientation ability, and function well as retarders, even when they are only 1/10 or less as thick as ordinary retardation films. The new CF also has excellent thermal stability. The change in retardation after heat treatment at 200°C for 30 min is around 5%, and there is no observable peeling. A prototype VA‐LCD made with our new CF provides good optical compensation, with the light leakage being extremely low in all azimuthal directions. This technology is very useful for making thin, highly reliable color filters for LCDs, even with other modes.  相似文献   
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