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991.
Assessed the effect of co-occurring versus not co-occurring internalizing and externalizing behavior problems on the reasons parents reported for clinical referral of their adolescent child. Reasons for referral were coded for 181 inpatient adolescents, and parent ratings of internalizing and externalizing behavior were obtained for a general population sample of 500 adolescents. Parents concurrently reported internalizing and externalizing behavior as reasons for referral less frequently (p < .0001) than would be expected given the correlation between these two domains in the general population sample. This suggests that the presence of externalizing problems may decrease parents' concern or awareness of internalizing problems, the presence of internalizing problems may decrease parents' concern or awareness of externalizing problems, or both. Implications for the clinical referral of adolescents and for informal parental efforts at helping their children with externalizing and internalizing problems are discussed.  相似文献   
992.
A total of 36,780,440 overseas travellers during 1979-1995 (17 years) were quarantined at Osaka and Kansai Airport Quarantine Station, 84,777 travellers reported themselves suffer from diarrhoea. Stools from 29,587 persons were bacteriologically examined. Various enteropathogenic bacteria were isolated from 9,766 (33.0%) patients of the stools examined. Isolated species were as follows: Plesiomonas shigelloides (3,234 cases); Salmonella spp. (2,236 cases); enterotoxgenic Escherichia coli (1,621 cases); Vibrio parahaemolyticus (1,959 cases); and Shigella spp. (1,242 cases). 1,278 different Shigella strains were isolated from 1,242 cases who were thus diagnosed as bacillary dysentery patients. The suspected regions or countries for infection of these cases were analysed. The serovars and antibiotic-sensitivities of the isolated strains were examined. Colicine typing of S. sonnei strains were also done. The results can be summarized as follows. 1) The most cases (53.4%) were infected in India. 2) The percentage distribution of sub-species of the strains was as follows; S. sonnei (57.8%), S flexneri (29.8%), S. boydii (8.4%), and S. dysenteriae (4.0%), respectively. 3) The major colicine type of S. sonnei strains were type 6 and 0. 4) The percentage of Antibiotic-resistant strains of each sub-species was S. dysenteriae (92.2%), S. sonnei (89.4%), S. flexneri (87.1%), and S. boydii (84.9%), respectively. The percentage of Antibiotic-resistant strains of S. flexneri were increased annually.  相似文献   
993.
The optical cross-connect (OXC) system described in this paper increases the operation flexibility and reliability of the trunk-line optical networks used for data communication. It features an OXC node comprised of a photonic switching network and a conventional electric switching network that are connected hierarchically. The operation and management scheme proposed for this OXC system uses the concept of an optical path and an optical section. The OXC system allows hitless network reconfiguration by switching the photonic switches gradually and without interference effects. An experimental OXC network showed that a broken optical path is restored, by rerouting, within 50 ms. Experiments using a LiNbO3 8×8 photonic switch matrix also showed that the OXC system provides photonic hitless switching. These results confirm the feasibility of flexibly reconfigurable and fast-restorable OXC systems  相似文献   
994.
995.
Access and metro networks based on WDM technologies   总被引:3,自引:0,他引:3  
This paper describes the technical issues of access and metro networks based on wavelength division multiplexing (WDM) technologies, some solutions, and an experimental demonstration. A WDM star access network with colorless optical network units (ONUs) is proposed. For realizing the colorless ONU, two approaches are introduced; optical carrier supply and spectrum slicing. In addition, a WDM metro ring network with scalable optical add/drop multiplexers (OADMs), namely the tapped-type OADM, is proposed to effectively accommodate the large amount of traffic issued from access networks. Prototypes are constructed and used to verify the feasibility of the proposed WDM technologies.  相似文献   
996.
The effects of heat loss on the burning velocity of cellular premixed flames are investigated by two-dimensional unsteady calculations of reactive flows based on the compressible Navier-Stokes equation and on the diffusive-thermal model equation. Hydrodynamic and diffusive-thermal instabilities are taken into account as contributing to the intrinsic instability of premixed flames. A sufficiently small disturbance is superimposed on a planar flame to obtain the relation between the growth rate and the wavenumber, i.e., the dispersion relation. As the heat loss becomes larger, the growth rate decreases and the unstable range narrows. This is because hydrodynamic instability caused by thermal expansion weakens for nonadiabatic flames. To investigate the characteristics of cellular flames, the disturbance with the linearly most unstable wavenumber, i.e., the critical wavenumber, is superimposed. As the superimposed disturbance evolves, the cellular-flame front forms due to the intrinsic instability. The lateral movement of cellular flames is observed at low Lewis numbers, and the behavior of cellular-flame fronts becomes more unstable for nonadiabatic flames. As the heat-loss parameter increases, the burning velocity of a cellular flame normalized by that of a planar flame increases at Lewis numbers lower than unity. By contrast, when the Lewis number is not less than unity, the burning-velocity increment decreases by increasing the heat loss. Diffusive-thermal instability thus has a pronounced influence on the unstable behavior and burning velocity of nonadiabatic cellular flames.  相似文献   
997.
We consider coding infinite sequences of a finite alphabet. The source is defined as a set of sequences (combinatorial source). The problem is to minimize the worst asymptotic compression ratio between each sequence and its coding output among the sequences in the combinatorial source. Ryabko showed that the optimal value coincides with the Hausdorff dimension of the combinatorial source. This correspondence extends the previous work in that the input and output costs are expressed in terms of not lengths but generalized costs. The essential quantity turns out to be the Hausdorff dimension with respect to the measure associated with the input cost. We construct an asymptotically optimal coding procedure, and also show that no coding scheme can beat the lower bound.  相似文献   
998.
We address the optimal location problem for two different types of service, designated as type-A and type-B, where some users may obtain both types of service in multi-purpose trips. We consider three user groups: (i) users of only the type-A service; (ii) users of only the type-B service; and (iii) users of both services in a single trip. We seek to locate three types of facilities: (i) type-A; (ii) type-B; and (iii) joint facilities that offer both services. We formulate a p-median-based model that minimizes the total travel distance and use it to investigate the effect of multi-purpose trip-makers on optimal facility types and locations. Examples are used to show that services tend to cluster in joint facilities, even when the proportion of multi-purpose behavior is small.  相似文献   
999.
In real control systems, certain constraints are placed on the input, state, and output values. If such constraints are violated, the system may become unstable, in a worst‐case scenario. One of the promising approaches to solving this problem is to switch the controller according to the state of the closed‐loop system. No useful design strategy for each controller, however, has yet been developed. In addition, the determination of the controller state at the instant of controller switching has not been investigated. First, this paper presents a new design methodology which merges the switching control and H controller design into one design algorithm. Second, this paper presents a way of determining the controller state at the instant of controller switching. Finally, the proposed method is applied to force control of a one‐DOF manipulator in order to demonstrate the usefulness of the proposed method. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 142(2): 68–75, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10082  相似文献   
1000.
Hypopharyngeal cancer is one of the head and neck cancers with poor prognosis. This is due to the unpredictable extension of the local disease and the high ratio of distant metastasis. To verify the morphological behavior of hypopharyngeal cancer, whole-mount horizontal serial sections were developed using the larynges obtained from total pharyngolaryngoesophagotomy. The technique of processing high-resolution three-dimensional (3D) images of the larynges using Nikon Cosmozone 2SA software is presented. Two representative surgical specimens were used and 3D images reconstructed. In these two particular cases, the cancer infiltrated superiorly through submucosal lymphatic ducts and formed separate daughter nests under the intact mucosal epithelium far above the main tumor. 3D images enhanced the morphological features of these cases. These cases also suggested the difficulty of defining the upper resecting limit in the operation of hypopharyngeal cancer. 3D reconstruction is and will be a crucial modality for studying the morphological behavior of hypopharyngeal cancer.  相似文献   
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