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121.
The D301 pipe jacking method is the first to accomplish long spans, curves and high speed construction in the field of small diameter (300 mm) tunneling. The design of the system components are described: tunneling machine with directional control ability, jacking machine, power unit, and control unit which contains a microprocessor. As a result of field tests in about 100 m in length with a 200 curvature radius, the following capabilities are confirmed: the span length is up to 100 m, the curvature radius is down to 200 m, it is useable in either cohesive or sandy soils having N‐curves up to 10, and the construction speed is up to 3 m∕h.  相似文献   
122.
 In [1], Homma-Kim-Yoo showed that a code C such that the support of the associated projective system is a union of two linear subspaces, is uniquely determined up to equivalence by its weight enumerator. Let W C (z) be the weight enumerator of a code C. Assuming certain conditions on the coefficients of W C (z) for some range, we prove that the support of the associated projective system is a union of two linear subspaces. Received: February 27, 2002; revised version: October 2, 2002 Keywords: Linear code, Projective system, Weight enumerator. MSC2000: 94B27, 94B65, 51E20 Partially supported by Grant-in-Aid for Scientific Research, Ministry of Education, #12640180  相似文献   
123.
A laser-guided BTA tool has been developed to prevent axial hole deviations. Four kinds of experiments were conducted to examine the performance of this tool in detail and to determine its practical application using a duralumin (A2017-T4) workpiece with a prebored 108-mm diameter hole. The first experiment was performed to examine the conditions of the hole deviation in the case of normal deep-hole boring. The second was to examine whether the tool corrects for the stated hole deviation. The third was to examine whether the tool can go straight through to the target without shifting toward a thin wall (t = 0.7 mm) on one side of the workpiece. The fourth was to examine whether the tool can be guided toward the target without affecting a prebored hole, which was inclined to radial direction at 100 μm for a hole length of 100 mm. The experiments were performed with a rotating tool-stationary workpiece system. Rotational speed was 270 rpm and feed ws 0.125 mm/rev. Tool diameter was 110 mm. The results show that the tool can be guided to go straight through toward the target despite the disturbances.  相似文献   
124.
Oligosaccharides derivatized with 4-aminobenzoic acid 2-(diethylamino) ethyl ester (ABDEAE) can be analyzed by ESI (Yoshino, K.; et al. Anal. Chem. 1995, 67, 4028-4031) and MALDI (Takao, T.; et al. Rapid Commun. Mass Spectrom. 1996, 10, 637-640) mass spectrometry. In this study, oligosaccharides derived from the enzymatic cleavage of the sugar chains of glycoproteins ribonuclease B, erythropoietin, and transferrin were subjected to ABDEAE derivatization, prior to analysis on a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI-TOF MS) for high-resolution mass measurement and a postsource decay (PSD) experiment. In the mass measurement of ABDEAE derivatives, quasi-molecular ion species have been observed in monoisotopic resolution using 2,5-dihydroxybenzoic acid as the matrix from spots that contain 50-200 fmol of sample; in the PSD analyses from the spots contained 500 fmol-1 pmol of sample, the predominant backbone ion series which covers the entire mass range for all the derivatives, the internal ion series which reflect the branched trimannosyl core structure of N-glycans, and the low m/z fingerprint ion of ABDEAE were consecutively observed, permitting structure elucidation of the oligosaccharides. Given the effectiveness of this derivatization in terms of its high sensitivity and resolution with respect to MALDI-TOF MS, current methodology is clearly applicable to the sensitive detection and accurate structural analysis of N-glycans.  相似文献   
125.
In realization of recursive digital filters with fixed point arithmetic, an error caused by roundoff arises. It is known that the level of the roundoff noise of an IIR filter tends to be high when the poles are close to the unit circle. Error feedback (EF) is an effective method to reduce the roundoff noise. It is desirable to design an EF network using as few parameters as possible in order to keep computational costs low. In this paper, we propose a method for designing a 2D EF network with identical coefficient sets. That is, the EF coefficients are divided into several subsets such that all the elements within each set have the same absolute value. In order to optimize the coefficient sets, we propose an algorithm by using the genetic algorithm. In the numerical example, we demonstrate the effectiveness of the proposed method.  相似文献   
126.
127.
The oxidation of C60 with m-chloroperbenzoic acid gave C60O2 with a high positional selectivity, as the 13C NMR analysis suggested. Diadducts C60CCI2O, C60CCl2(anthracene), C60CCl2[(CH2CH2)2N2], and C60CCI2[Pt-(PPh3)2] were synthesized, isolated, and characterized by negative ion FAB mass spectroscopy.  相似文献   
128.
We determined the structure and site of fatty acid incorporated in octopus rhodopsin using a combination of fluorescence label and enzymatic cleavage methods in conjunction with fast-atom bombardment (FAB) mass spectrometry. A single peptide containing two adjacent cysteines, Cys337 and Cys338, was successfully isolated using the fluorescence from a dye conjugated to Cys345. The FAB mass spectrometric analysis of the peptide (323Phe-340Phe) revealed that two palmitoyl groups are linked to Cys337 and Cys338 via thioester bonds in octopus rhodopsin as in bovine rhodopsin.  相似文献   
129.
A 24-year-old woman with atopic dermatitis was admitted to our hospital with fever. Echocardiography showed a huge vegetation attached to the posterior mitral commissure without mitral valve dysfunction. Blood culture identified methicillin-sensitive Staphylococcus aureus. The serum level of antiphospholipid antibody was elevated. A splenic infarction occurred on the second hospital day. Surgery to resect the residual mobile vegetation was performed uneventfully on the 6th hospital day. The postoperative course was uneventful, and the patient was discharged after 4 weeks of antibiotic therapy. Preservation of the mitral valve is rare in the face of virulent Staphylococcus infection and the presence of a huge mobile vegetation. These findings were apparently related to the high serum level of infection-related antiphospholipid antibody and atopic dermatitis.  相似文献   
130.
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