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81.
The soil–pipeline interactions in sand under lateral and upward movements are investigated with particular attention to the peak forces exerted on the pipe. The analytical solutions for estimating the peak forces are summarized and it is shown that, for deep embedment condition, there is large uncertainty in the true values since the bounds established by the analytical solutions are large. In order to find the solution for the peak force and to investigate its transition from shallow to deep failure mechanism, finite element analyses of lateral and upward pipe movements are performed for different embedment conditions. Two different soil models (Mohr–Coulomb and Nor–Sand models) are used for the simulations. The accuracy of the analysis is first examined by simulating experimental tank tests. The analysis is further extended to deeper embedment ratios of as large as 100. The obtained finite element results are used to construct a design chart for deep embedded pipelines.  相似文献   
82.
This paper shows that probabilistic relaxation is an effective method in the automatic interpretation of line drawings consisting of lines, symbols, and characters, such as electricity distribution diagrams superimposed on maps. The line interpretation problem has been newly formulated as a labeling problem in which probabilistic relaxation is used to obtain globally consistent results. The proposed automatic interpretation method consists of two stages. The first is segmentation and recognition of primitive components, such as symbols, characters, and long lines. The second is long-line interpretation, where probabilistic relaxation is introduced.  相似文献   
83.
Copolyamides were prepared from 4,4′-dichloroformylbenzil, adipyldichloride and hexamethylenediamine. The melting points and solubilities of the copolyamides varied with benzil content. The copolyamides were irradiated by u.v. light in solution and in a film. The copolyamide irradiated in solution was still soluble but the copolyamide irradiated in a film was crosslinked. The mechanisms of the photochemical reactions are discussed.  相似文献   
84.
This paper presents an approach to the problem of estimating the number of exponential functions and the pertinent parameters in the output of a radioactive tracer kinetic process. In particular, application of a criterion called an information theoretical criterion (AIC) for the estimation of the number of exponential functions is proposed; AIC was introduced by Akaike for the estimation of the order of linear dynamical systems and has been successfully applied for statistical model identification in a wide range of fields. Also, the maximum likelihood method was applied in order to evaluate AIC and to estimate decay constants and coefficients.  相似文献   
85.
86.
Summary It is for the first time found that poly(N-vinylcarbazole)(PVCz)/polystyrene (PS) blends have lower miscibility on molecular level than that of PVCz/polyoxyethylene (PEO) blends. This is obtained from excimer fluorescence properties of PVCz in PVCz (9.1–100%)/PS and PVCz (9.6–100%)/PEO blends. Schematic diagrams of phase-separated structure of the PVCz blends are proposed consistent with emission properties and phase-contrast microscopic images. Received: 8 February 2000/Revised version: 21 March 2000/Accepted: 27 March 2000  相似文献   
87.
Skin is the largest organ of human body which can easily be observed non-invasively, but objective assessment of skin status is difficult. Therefore, we have focused on the oxygen saturation, and proposed the iterative optical path-length matrix method (OPLM) for estimating oxygen saturation of skin. Oxygen saturation of skin may help finding pre-disease state. In Kampo medicine (Japanese traditional herbal medicine), inspection of skin and tongue is one of the principal methods for diagnosis of the state. Kampo medicine contains a number of concepts which are useful for preventive medicine. The Oketsu status is a pathological concept in Kampo medicine, primarily denoting blood stasis/stagnation. In this study, we focused on oxygen saturation of skin as an objective index of skin properties, and studied correlation with the blood flow and the Oketsu score. First, we acquired Oketsu score of the patients, and measured oxygen saturation, hemoglobin concentration and blood flow of the patients at two locations: fingertip of the right first finger and dorsal surface of the right hand. Then, correlation among the values was calculated. As the result, the oxygen saturation showed large correlation with the blood flow and the Oketsu score at dorsal surface of hand. The oxygen saturation of skin will reflect systemic blood flow and Oketsu status, and it would help objective diagnosis by measuring skin color spectrum.  相似文献   
88.
November 20, 2010, marked a significant milestone in the annals of human endeavors in space since it was the twelfth anniversary of one of the most challenging and complex construction projects ever attempted by humans away from our planet: The construction of the International Space Stations. On November 20, 1998, the Zarya Control Module was launched. With this simple, almost unnoticed launch in the science community, the construction of a continuously staffed research platform, in Low Earth Orbit, was underway. This paper discusses the research that was performed by many occupants of this research platform during the year celebrating its twelfth anniversary. The main objectives of this paper are fourfold: (1) to discuss the integrated manner in which science planning/replanning and prioritization during the execution phase of an increment is carried out across the United States Orbital Segment since that segment is made of four independent space agencies; (2) to discuss and summarize the research that was performed during increments 16 and 17 (October 2007 to October 2008). The discussion for these two increments is primarily focused on the main objectives of each investigation and its associated hypotheses that were investigated. Whenever available and approved, preliminary research results are also discussed for each of the investigations performed during these two increments; (3) to compare the planned research portfolio for these two increments versus what was actually accomplished during the execution phase in order to discuss the challenges associated with planning and performing research in a space laboratory located over 240 miles up in space, away from the ground support team; (4) to briefly touch on the research portfolio of increments 18 and 19/20 as the International Space Station begins its next decade in Low Earth Orbit.  相似文献   
89.
In this study, the amount of copper or cadmium adsorbed using waste biomass (i.e., coffee grounds (CG) and rice bran (RB)) was investigated. The amount of crude protein in defatted CG (D-CG) or RB (D-RB) was greater than that in CG or RB, respectively. The amount of copper or cadmium adsorbed using CG was greater than that using RB. Additionally, the amount of copper or cadmium adsorbed was not affected by the presence of fat in CG. Adsorption data was fitted to the Freundlich equation, and the correlation coefficients were in the range of 0.794-0.991. The main adsorption mechanism was thought to be monolayer adsorption onto the surface of the waste biomass. The adsorption rate data was fitted to the pseudo-second-order model, and the correlation coefficient average was in the range of 0.891-0.945. This result showed that the rate-limiting step may be chemisorption. Moreover, the amount of copper or cadmium desorbed from CG or RB using 0.01 mol/L or 1.00 mol/L HNO(3) was investigated. Desorption with 0.01 mol/L HNO(3) resulted in the recovery of 86-97% of the copper and cadmium, indicating that copper or cadmium that was adsorbed using waste biomass was recoverable.  相似文献   
90.
In the present study, the phosphate adsorption abilities of granular materials, gibbsite (GB) and cerium hydroxide (CE), granulated with ethyl cellulose and ethanol, were investigated. For suitable granular conditions using GB or CE, the percentage of binder and amount of solvent were 10% and 3.25 mL/5 g for GB and 7.5% and 2.50 mL/5 g for CE. The amount of phosphate adsorbed by granular GB or CE was similar to that adsorbed by powdered GB or CE. The adsorption isotherms of phosphate were also similar for the granular and powdered materials. The results of a column experiment showed that when GB was used, the suitable concentration of sodium hydroxide as the desorption solution was 2 mmol/L. In these experiments, the amount of phosphate adsorbed was 31.4 mg/g, the amount of phosphate desorbed was 25.3 mg/g, and the recovery percentage was 80.5%. In contrast, when CE was used, the suitable concentration of sodium hydroxide was 500 mmol/L; the amount of phosphate adsorbed was 77.7 mg/g, the amount of phosphate desorbed was 57.8 mg/g, and the recovery percentage was 74.4%. Results also indicate that granular GB and CE could be used at least five times in a column without loss of absorption or desorption abilities. Moreover, granulation of GB and CE is possible using ethyl cellulose and ethanol.  相似文献   
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