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雷达备件及时供应对于雷达技术装备保障业务极为重要,快捷、便利的雷达备件信息查询可以提高保障工作效率,本文介绍了利用ASP.NET+SOLServer技术开发雷达备件信息管理系统的过程,包括开发环境、功能结构、系统架构、数据库的设计以及系统功能的实现。系统界面简洁,易于操作。 相似文献
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新一代天气雷达2009—2014年运行状态分析 总被引:2,自引:2,他引:0
综合气象观测系统运行监控平台(ASOM)是地面观测设备实时运行状态及探测数据的监控保障系统,文章基于ASOM中2009年12月1日至2014年11月30日的维护维修数据对新一代天气雷达运行指标进行评估,统计其业务可用性(Ao)、平均无故障工作时间(MTBF)、平均故障持续时间(Tfd)、故障次数(Nf)和故障分布情况,2014年,Ao和MTBF分别提高到99.06%和1465.08 h,Tfd和Nf分别降低至13.15 h和4.68次。此外文章对故障案例中的备件更换情况按照雷达分系统和不同型号进行统计分类,建立针对性的备件供应管理,以提高新一代天气雷达的维修能力,提升综合观测系统装备供应管理效能。 相似文献
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1引言“存货”是国际上通用的一个名称,也是企业财务会计制度上使用的一个概念。1996年国务院批准的《事业单位财务规则》中引用了这个概念,并提出核算和管理原则。所谓“存货”是指事业单位在开展业务及其他活动中为耗用而储存的资产,包括材料、燃料、包装物和低值易耗品等。我们单位负责供应全省气象系统业务所需设备及各类消耗器材和设备维修备件、检定备件,是核算存货量较大的单位。国家为了气象事业发展,每年投入大量资金用于购量储备业务所需器材。就我省而言,每年省局拨给此项经费助多万元,但因物价上涨等因素,这些资金远远… 相似文献
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综合气象观测运行监控业务及系统升级设计 总被引:3,自引:0,他引:3
通过对综合气象观测运行监控业务及运行监控系统现状的分析,提出了运行监控业务的发展设想,并对运行监控系统升级做了科学的设计。结果指出,运行监控业务将成为装备保障工作的核心中枢,具有监控、指挥、调度、管理功能,应形成设备监控、维修保障、装备供应与评估业务关联互动的业务体系。运行监控系统需突破目前依赖观测资料质量检查为主要手段的技术,建立以设备自身状态信息为主,故障维修业务填报信息和观测资料检查等多元信息相互校验的技术,实现监控、维修保障、装备供应的信息联动。 相似文献
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《沙漠与绿洲气象(新疆气象)》2008,2(2):F0002-F0002
新疆气象技术装备保障中心是新疆气象局直属事业单位,下设办公室、技术保障科、物资供应站、检定所(与气象计量站合署办公)、科技服务科五个科室,主要负责全疆气象装备和器材的计划、采购、供应、仓储工作,承担全疆气象雷达、自动气象站、雷电监测设备,大气观测设备,气象仪器,电解水制氢设备,通讯设备, 相似文献
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气象事业的发展离不开先进的设备,做好气象物资的供应管理是保障气象发展的前提,是气象业务顺利开展的重要保障。加强气象物资的供应管理才能使各种物资最大限度的发挥作用,让各种物资达到最佳组合,节约资源,降低成本。本着节约、环保、高效的原则,依据《气象技术装备管理办法》,做好物资计划、采购、储备、配送等工作。本文主要简述基于节约、环保、高效原则,如何做好气象装备的储存、保管、供应各环节的工作。 相似文献
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The following Henry's law constants (K
H/mol2kg-2atm-1) for HNO3 and the hydrohalic acids have been evaluated from available partial pressure and other thermodynamic data from 0°–40°C, 1 atm total pressure: HNO
3
, 40°C–5.85×105; 30°C–1.50×106; 25°C–2.45×106; 20°C–4.04×106; 10°C–1.15×107; 0°C–3.41×107. HF, 40°C–3.2; 30°C–6.6; 25°C–9.61; 20°C–14.0; 10°C–32.0; 0°C–76. HCl, 40°C–4.66×105; 30°C–1.23×106; 25°C–2.04×106; 20°C–3.37×106; 10°C–9.71×106; 0°C–2.95×107. HBr, 40°C–2.5×108; 30°C–7.5×108; 25°C–1.32×109; 20°C–2.37×109; 10°C–8.10×109; 0°C–3.0×1010. HI, 40°C–5.2×108; 30°C–1.5×109; 25°C–2.5×109; 20°C–4.5×109; 10°C–1.5×1010; 0°C–5.0×1010. Simple equilibrium models suggest that HNO3, CH3SO3H and other acids up to 10x less soluble than HCl displace it from marine seasalt aerosols. HF is displaced preferentially to HCl by dissolved acidity at all relative humidities greater than about 80%, and should be entirely depleted in aged marine aerosols. 相似文献
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The relationship between the geometrical structure of a canopy layer and the bulk transfer coefficient was investigated using a numerical canopy model. The following results were obtained:
- The bulk transfer coefficients for momentum and heat, C M and C H , change with non-dimensional canopy density C * each has a maximum.
- The value of C M is always larger than the value of C H for a canopy with c m > c h , c m and c h being the drag coefficient and the heat transfer coefficient of an individual canopy element, respectively.
- The value of C * at which C H has its maximum value is larger than the value of C * at which C M has its maximum. Therefore, the reciprocal of the sublayer Stanton number b h ?1 ranges between 50 and 65 for C * around 0.1 while it ranges between 0 and 30 for C * < 10?2 and C * > 2 (when c m = 0.5).
- The value of B H ?1 in the present study is consistent with most available observations, except for canopies of medium density (when C * is around 0.1) for which no observational value has been obtained.
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Ronald B. Smith 《Boundary-Layer Meteorology》2008,129(3):371-393
Dispersion estimates with a Gaussian plume model are often incorrect because of particle settling (β), deposition (γ) or the vertical gradient in diffusivity (K
v
(z) = K
0 + μz). These “non-Gaussian” effects, and the interaction between them, can be evaluated with a new Hankel/Fourier method. Due
to the deepening of the plume downwind and reduced vertical concentration gradients, these effects become more important at
greater distance from the source. They dominate when distance from the source exceeds L
β
= K
0
U/β
2, L
γ
= K
0
U/γ
2 and L
μ
= K
0
U/μ
2 respectively. In this case, the ratio β/μ plays a central role and when β/μ = 1/2 the effects of settling and K gradient exactly cancel. A general computational method and several specific closed form
solutions are given, including a new dispersion relation for the case when all three non-Gaussian effects are strong. A more
general result is that surface concentration scales as C(x) ~ γ
−2 whenever deposition is strong. Categorization of dispersion problems using β/μ, L
γ
and L
μ
is proposed. 相似文献
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S. A. Hsu 《Boundary-Layer Meteorology》1994,71(1-2):205-209
Under growing wind-wave conditions the shear velocity,u
*, over the water surface equalsg
2
H
s
2
B
a
2
C
p
3
, whereg is the gravitational acceleration,H
s
is the significant wave height,B
a
is a constant, andC
p
is the wave celerity. From an independent field experiment in a lake environment which provided all three parameters (u
*,H
s
, andC
p
), the value ofB
a
is found to be 0.89, which is slightly lower than but consistent (within 20%) with the literature value between 0.90 and 1.06 obtained from an oceanic environment. Since thisu
* equation does not include the wind speed,U
10, anotheru
* formulation withU
10 in addition to the wave information is also evaluated. It is shown that the latter equation which includesU
10 is superior to the former withoutU
10. 相似文献
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Derek D. Stretch James W. Rottman S.Karan Venayagamoorthy Keiko K. Nomura Chris R. Rehmann 《Dynamics of Atmospheres and Oceans》2010
Mixing efficiency in stratified flows is a measure of the proportion of turbulent kinetic energy that goes into increasing the potential energy of the fluid by irreversible mixing. In this research direct numerical simulations (DNS) and rapid distortion theory (RDT) calculations of transient turbulent mixing events are carried out in order to study this aspect of mixing. In particular, DNS and RDT of decaying, homogeneous, stably-stratified turbulence are used to determine the mixing efficiency as a function of the initial turbulence Richardson number Rit0=(NL0/u0)2, where N is the buoyancy frequency and L0 and u0 are initial length and velocity scales of the turbulence. The results show that the mixing efficiency increases with increasing Rit0 for small Rit0, but for larger Rit0 the mixing efficiency becomes approximately constant. These results are compared with data from towed grid experiments. There is qualitative agreement between the DNS results and the available experimental data, but significant quantitative discrepancies. The grid turbulence experiments suggest a maximum mixing efficiency (at large Rit0) of about 6%, while the DNS and RDT results give about 30%. We consider two possible reasons for this discrepancy: Prandtl number effects and non-matching initial conditions. We conclude that the main source of the disagreement probably is due to inaccuracy in determining the initial turbulence energy input in the case of the grid turbulence experiments. 相似文献
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A time series of microwave radiometric profiles over Arctic Canada’s Cape Bathurst (70°N, 124.5°W) flaw lead polynya region
from 1 January to 30 June, 2008 was examined to determine the general characteristics of the atmospheric boundary layer in
winter and spring. A surface based or elevated inversion was present on 97% of winter (January–March) days, and on 77% of
spring (April–June) days. The inversion was the deepest in the first week of March (≈1100 m), and the shallowest in June (≈250 m).
The mean temperature and absolute humidity from the surface to the top of the inversion averaged 250.1 K (−23.1°C), and 0.56 × 10−3 kg m−3 in winter, and in spring averaged 267.5 K (−5.6°C), and 2.77 × 10−3 kg m−3. The median winter atmospheric boundary-layer (ABL) potential temperature profile provided evidence of a shallow, weakly
stable internal boundary layer (surface to 350 m) topped by an inversion (350–1,000 m). The median spring profile showed a
shallow, near-neutral internal boundary layer (surface to 350 m) under an elevated inversion (600–800 m). The median ABL absolute
humidity profiles were weakly positive in winter and negative in spring. Estimates of the convergence of sensible heat and
water vapour from the surface that could have produced the turbulent internal boundary layers of the median profiles were
0.67 MJ m−2 and 13.1 × 10−3 kg m−2 for the winter season, and 0.66 MJ m−2 and 33.4 × 10−3 kg m−2 for the spring season. With fetches of 10–100 km, these accumulations may have resulted from a surface sensible heat flux
of 15–185 W m−2, plus a surface moisture flux of 0.001–0.013 mm h−1 (or a latent heat flux of 0.7–8.8 W m−2) in winter, and 0.003–0.033 mm h−1 (or a latent heat flux of 2–22 W m−2) in spring. 相似文献
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A spectral approach is applied to shear-induced turbulence in stratified layers. A system of spectral equations for stationary balance of turbulent energy and temperature variances was deduced in the vicinity of the local shear scale LU = (ε/UZ3)1/2. At wavenumbers between the inertial-convective (k−5/3) and wak turbulence (k−3) subranges, additional narrow spectral intervals—‘production’ subranges—may appear (E k−1, ET k−2). The upper boundary of these subranges is determined as LU, and the lower boundaries as LR (ε/UZN2)1/2(χ/TZ2). It is shown that the scale LU is a unique spectral scale that is uniform up to a constant value for every hydrophysical field. It appears that the spectral scale LU is equivalent to the Thorpe scale LTh for the active turbulence model. Therefore, if turbulent patches are generated in a background of permanent mean shear, a linear relation between temperature and mass diffusivities exists. In spectral terms, the fossil turbulence model corresponds to the regime of the Boldgiano-Obukhov buoyancy subrange (E k−11/5, ET k−7/5). During decay the buoyancy subrange is expanded to lower and higher wavenumbers. At lower wavenumbers the buoyancy subrange is bounded by L** = 3(χ1/2/N1/2TZ), which is equivalent to the Thorpe scale LTh. In such a transition regime only, when the viscous dissipation rate is removed from the set of main turbulence parameters, the Thorpe scale does not correlate with the buoyancy scale LN ε1/2/N3/2 and fossil turbulence is realized. Oceanic turbulence measurements in the equatorial Pacific near Baker Island confirm the main ideas of the active and fossil turbulence models. 相似文献