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排序方式: 共有363条查询结果,搜索用时 15 毫秒
31.
A passive aerodynamic control method for suppression of the wind-induced instabilities of a very long span bridge is presented in this paper. The control system consists of additional control flaps attached to the edges of the bridge deck. Control flap rotations are governed by prestressed springs and additional cables spanned between the control flaps and an auxiliary transverse beam supported by the main cables of the bridge. The rotational movement of the flaps is used to modify the aerodynamic forces acting on the deck and provides aerodynamic forces on the flaps used to stabilize the bridge. A time-domain formulation of self-excited forces for the whole three-dimensional suspension bridge model is obtained through a rational function approximation of the generalized Theodorsen function and implemented in the FEM formulation. This paper lays the theoretical groundwork for the one that follows. 相似文献
32.
Five sterylglycosides (acylmono-, mono-, di tri- and tetraglycosylsterol) and a saponin were isolated from Adzuki beans and
characterized. In the glycosylsterols, the principal component sterols were sitosterol and stigmasterol; the major sugar component
was glucose. The glucose units were shown to be linked by β1,6-bonds. The three oligoglycosylsterols were shown to be gentiobiosylsterol,
gentiotriosylsterol and gentiotetraosylsterol; the latter two are novel sterylglycosides. The saponin was identified as glucopyranosyl-(β1→2)-glucopyranurosyl-(β1→3′)-soyasapogenol
B (Azukisaponin I) which had previously been found in Adzuki beans. 相似文献
33.
K Tayama H Akashi T Fujino T Okazaki S Aoyagi 《Canadian Metallurgical Quarterly》1998,51(13):1074-1079
34.
35.
Determining whether there is evidence of underutilization of outpatient mental health care by Department of Defense (DoD) beneficiaries relative to the general population is the purpose of this study. It analyzes data from the 1994-1995 DoD Health Beneficiary Survey and compares the mental health status and usage rates of active duty members and their families with benchmark levels found in the general population. Although the mental health status for the DoD beneficiary population was found to be generally the same as that of the general U.S. population within gender categories, gender-specific usage rates of mental health services of DoD beneficiaries in the groups examined were well below rates recorded for the general population. The concept of psychological readiness is also introduced. Several recommendations for increasing access to mental health care are presented. 相似文献
36.
N Hisano Y Yatomi MA Fujino Y Igarashi S Kume Y Ozaki 《Canadian Metallurgical Quarterly》1998,123(2):263-268
OBJECTIVE: This study aimed to investigate the incidence of cystoid macular edema and anterior uveitis associated with the use of latanoprost. DESIGN: A retrospective review of patients treated with latanoprost in the authors' practice between September 1, 1996, and August 1, 1997, was performed. PARTICIPANTS: Ninety-four patients and 163 eyes were studied. INTERVENTION: Patients presenting with signs and symptoms of ocular inflammation while receiving latanoprost were noted, and their response to the discontinuation of the drug was recorded. MAIN OUTCOME MEASURES: The presence and degree of anterior uveitis and cystoid macular edema were measured. RESULTS: Six (6.4%) of 94 patients (8 [4.9%] of 163 eyes) had anterior uveitis develop, and 2 (2.1%) of 94 patients (2 [1.2%] of 163 eyes) had cystoid macular edema develop while being treated with latanoprost. CONCLUSION: Although latanoprost is an effective ocular-hypotensive agent, the authors' experience with the drug has shown a significant incidence of anterior uveitis and cystoid macular edema. To the authors' knowledge, this is the first study to report the incidence of both cystoid macular edema and anterior uveitis associated with latanoprost therapy. Treating physicians should be aware of these potential complicating side effects of latanoprost. 相似文献
37.
Hiroyuki Mori Yoshinori Sakatani Tatsurou Fujino Kazuyuki Numa 《Electrical Engineering in Japan》2006,156(2):43-51
In this paper, a new efficient feature extraction method is proposed to handle the one‐step‐ahead daily maximum load forecasting. In recent years, power systems become more complicated under the deregulated and competitive environment. As a result, it is not easy to understand the cause and effect of short‐term load forecasting with a bunch of data. This paper analyzes load data from the standpoint of data mining. By it we mean a technique that finds out rules or knowledge through large database. As a data mining method for load forecasting, this paper focuses on the regression tree that handles continuous variables and expresses a knowledge rule as if‐then rules. Investigating the variable importance of the regression tree gives information on the transition of the load forecasting models. This paper proposes a feature extraction method for examining the variable importance. The proposed method allows to classify the transition of the variable importance through actual data. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(2): 43–51, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20104 相似文献
38.
We investigated whether nitric oxide (NO) exerts an inhibition on its own synthesis in the gastric myenteric plexus in rats. Nonadrenergic, noncholinergic relaxations in response to transmural electrical stimulation (TS) were markedly antagonized by NG-nitro-L-arginine methyl ester, (10(-4) M) and abolished by tetrodotoxin (10(-6) M). Pretreatment with various NO donors (3-morpholino-sydnonymide [SIN-1 (3 x 10(-7) to 3 x 10(-6) M)], S-nitroso-N-acetylpenicillamine (10(-6) to 10(-5) M), sodium nitroprusside (10(-8) to 3 x 10(-8) M) and 8-bromoquanosine 3', 5'-cyclic monophosphate [8-bromo-cGMP (10(-6) to 3 x 10(-6) M)]) significantly inhibited TS-evoked nonadrenergic, noncholinergic relaxations in a dose-dependent manner. In contrast, vasoactive intestinal polypeptide (10(-8) M)-induced relaxations were not affected by SIN-1 or 8-bromo-cGMP. TS evoked a significant increase in 3H-citrulline formation, which was completely abolished by calcium-free medium, NG-nitro-L-arginine methyl ester, (10(-4) M) and tetrodotoxin (10(-6) M). 3H-citrulline formation evoked by TS was significantly inhibited by SIN-1 (10(-7) to 10(-5) M) and 8-bromo-cGMP (10(-7) to 10(-5) M) in a dose-dependent manner. The inhibitory effect of SIN-1 was partially prevented by 1H-[1,2, 4]oxadiazolo[3,4-a]quinoxalin-1-one (10(-5) M), a guanylate cyclase inhibitor. We conclude that NO synthesis in the gastric myenteric plexus is negatively regulated by NO and cGMP. This suggests an autoregulatory feedback mechanism of NO synthesis in the gastric myenteric plexus. 相似文献
39.
Surface Finishing of Micropins Produced by WEDG 总被引:1,自引:0,他引:1
This paper presents a new method of surface finishing for micropin products. Precision micropins thinner than ø100 urn can be produced by WEDG (wire electrodischarge grinding). However, the surface quality of the products is not sufficient for applications that require mirrorlike surface and/or a surface without a heat-affected zone. A succession of two processes, WEDG and lapping, is proposed and tested for its feasibility. In order to ensure the control of the lapping conditions, micropins were WEDGed and lapped on the same machine. The wire electrode for WEDG was used as the lapping tool. A smooth, craterless surface with Ra=18 nm was achieved. 相似文献
40.
A modified sequence of insulin B21-26, beta-Ala-Arg-Gly-Phe-Phe-Tyr-NH2 (DP-432), was synthesized and tested for its biological activities. The hexapeptide, ip injected to mice, stimulated [U-14C]-glucose incorporation into diaphragm glycogen and adipose tissue total lipid. Neither plasma glucose nor FFA (free fatty acid) was reduced by the injection. However, when injected with epinephrine, the peptide prevented a rise of plasma FFA but not that of plasma glucose due to epinephrine. In vitro, the peptide stimulated glucose oxidation and inhibited epinephrine- or isoproterenol-stimulated lipolysis of mouse adipose tissue. Furthermore, when added along with insulin to incubation media, the peptide exaggerated the effects of insulin on both glucose oxidation and isoproterenol-stimulated lipolysis. The hexapeptide thus seems to have an insulin-potentiating action as well as insulin like activities on peripheral tissue. 相似文献