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1.
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   
2.
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   
3.
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   
4.
Various naturally occurring strains of heterotrophic nitrifying bacteria were isolated by enrichment culture using acetamide as the C and N source, and 21 strains were identified as heterotrophic nitrifiers. Using a new simple procedure, these 21 strains were also investigated for the ability to carry out denitrifcation in the presence of oxygen. Several of the nitrifying strains were found to exhibit a distinct activity that allows for denitrifcation via nitrite (NO2-) in the presence of oxygen, indicating that they have an oxygen-tolerant denitrifcation system. A wide variety of bacteria possessing both nitrification and denitrifcation capabilities in the presence of oxygen were isolated and partially characterized by using the simple screening combinatorial procedure described in this paper.  相似文献   
5.
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   
6.
A 1-million transistor 64-b microprocessor has been fabricated using 0.8-μm double-metal CMOS technology. A 40-MIPS (million instructions per second) and 20-MFLOPS (million floating-point operations per second) peak performance at 40 MHz is realized by a self-clocked register file and two translation lookaside buffers (TLBs) with word-line transition detection circuits. The processor contains an integer unit based on the SPARC (scalable processor architecture) RISC (reduced instruction set computer) architecture, a floating-point unit (FPU) which executes IEEE-754 single- and double-precision floating-point operations a 6-KB three-way set-associative physical instruction cache, a 2-KB two-way set-associative physical data cache, a memory management unit that has two TLBs, and a bus control unit with an ECC (error-correcting code) circuit  相似文献   
7.
Separation of matrix metals in composites was tried on alumina short fiber-reinforced aluminum and 6061 alloy composites and SiC whisker-reinforced 6061 alloy composite for recycling. It is possible to separate molten matrix metals from fibers in the composites using fluxes that are used for melt treatment to remove inclusions. About 50 vol pct of the matrix metals was separated from the alumina short fiber-reinforced composites. The separation ratio of the matrix from the SiC whisker-reinforced 6061 alloy composite was low and about 20 vol pct. The separation mechanism was discussed thermodynamically using interface free energies. Since the flux/fiber interface energy is smaller than the aluminum/fiber interface energy, the replacement of aluminum with fluxes in composites takes place easily. Gases released by the decomposition of fluxes act an important role in pushing out the molten matrix metal from the composite. The role was confirmed by the great amount cavity formed in the composite after the matrix metal flowed out.  相似文献   
8.
Olefin-aldehyde condensation reaction on solid acids   总被引:1,自引:0,他引:1  
A vapor phase octadiene synthesis from isobutyraldehyde and isobutene was examined over various catalysts at 523 K. Although solid bases were totally inactive, solid acids exhibited high activity to yield dienes. Niobic acid was found to be an excellent catalyst in the total yield. WO3/TiO2 and Ag-O/SiO2 were also excellent catalysts with respect to the diene selectivity (98–99%), though the yields were slightly lower than that of niobic acid. Acid strength required for the reaction was found to be in the range of −8.2 Ho −3.0. Reactions from furan derivatives and octanol were also investigated.  相似文献   
9.
We developed a root cause analysis (RCA) system for an enterprise IT system environment. In this paper, we propose a rule‐construction method that builds analysis rule data objects from general analysis rules and the topology information of the actual target IT environment. Using this method, the IT administrator can use the RCA system without any manual rule modifications. For the execution of the analysis, we introduce the certainty factor to realize robust analysis when the order and reachability of a fault event cannot be guaranteed.  相似文献   
10.
Abstract

Robots composed of hydraulic actuators have been utilized in various fields and at disaster sites. However, the hydraulic control system for multiple-degree-of-freedom mechanisms is large because such systems require many control components. The purpose of this research was to develop a small hydraulic flow control valve. This paper describes the fabrication and evaluation of a small three-way valve by particle excitation using a piezoelectric transducer. This valve consists of two transducers and can switch the inlet and outlet ports by applying an AC voltage of different driving frequencies to each transducer because each transducer has different resonant frequencies. The flow rate was controlled by applying a voltage to the piezoelectric transducer. We evaluated the vibration characteristics of the fabricated three-way valve. The vibration velocity exhibited peaks at 120 and 155 kHz for the inlet and outlet port, respectively, and that of each transducer increased with the applied voltage. Therefore, this three-way valve can switch the opening port by changing the driving frequencies and continuously controlling the flow rate. As a result, we have succeeded in driving the novel small three-way valve.  相似文献   
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