A hydromagnetic vortex seen by ISEE-1 and 2

Magnetometer and plasma data from the dual ISEE spacecraft are combined in a study of the initial plasma vortex event reported by Honeset al. (1978) in the dawn plasma sheet. The event is a transient hydromagnetic wave of two cycles duration with a six minute period. Large amplitude compressional and transverse magnetic components were present. Particle and magnetic pressure oscillations were in strict antiphase, but did not balance. When combined with the plasma velocity data these properties show that substantial Earthward field-aligned flows of electromagnetic energy and heat flux occurred during the vortex. The nett energy flow perpendicular to B was in the antisolar direction. This event possesses hydromagnetic features unique to a hot plasma environment.     

High latitude stratospheric electrical measurements in fair and foul weather under various solar conditions

Stratospheric electric field and conductivity measurements during a wide variety of weather and solar conditions are presented. These data are all from high latitude sites (> 50°N GG) in the months of either April or August. The vector electric field is determined by orthogonal double probes connected through high impedance inputs to differential electrometers. The direct conductivity measurement involves determining the relaxation time constant of the medium after refloating a shorted pair of separated probes. Vertical electric field data from several balloon flights with average duration of 18 h at ceiling in fair weather are shown to be well modeled by a simple exponential altitude dependent equation. Examples of solar flare and magnetospheric effects on stratospheric electric fields are shown. Data collected over electrified clouds and thunderstorms are presented along with a discussion of the thunderstorm related electric currents. Lightning stroke signatures in the stratosphere during a large thunderstorm are identified in the electric field data. Current surges through the stratosphere due to DC currents as well as the sferic are calculated. In nearly 1000 h of balloon data no direct solar influence is identified in these data except during major flares. However, variations in all three components of the electric field during magnetically active conditions are discussed.     

The equatorial electrojet and associated currents as seen in Magsat data

Magsat data are re-examined with regard to the presence and character of fields due to the equatorial electrojet and meridional currents at dawn and dusk local times. Dip-latitude organized field variations at dawn are:

• 1.(1) extremely weak,
• 2.(2) extremely variable with longitude,
• 3.(3) inconsistent with the pattern expected from a line or narrow sheet current.

It is shown that the use of Magsat dusk data can ‘contaminate’ a main field model, introducing apparent equatorial electrojet effects into the dawn data.Fields due to the equatorial electrojet and (presumably) associated meridional currents are clearly present in the dusk data. They show a variation with longitude which is apparently associated with the longitudinal variation of the strength, or square of the strength, of the main field in the E-region. Also evident is a variation with time of the year, although data are available for only a six month period. The meridional currents are generally minimum during January and February and maximum either during November and December or March and April, depending upon longitude. The E-region horizontal currents are minimum in November and December and maximum in March and April, except for − 30° to −90° longitude when the maximum occurs in January and February.Assuming that field gradients in local time are considerably smaller than field gradients in dip-latitude, current densities are estimated to be 1–3.6μA/m² for the horizontal current at 110km and about 10–20 × 10⁻⁹ A/m² for the vertical currents at 400km altitude. These results confirm and extend earlier results of Takeda and Maeda.Most models of the electrojet system in the literature disagree severely with these measurements either because their scope is inadequate or because of the wind system they assume. Those models which best describe the data invoke an eastward wind and/or an eastward electric field at dusk local time.     

Concentrations of H2O and NO in the mesosphere and the lower thermosphere at high latitudes

Water vapour and nitric oxide concentrations in the mesosphere and lower thermosphere were derived from infrared emission and positive ion composition measurements above northern Europe during the Energy Budget Campaign 1980. The experiments were performed at different levels of geomagnetic disturbance. Both water vapour and nitric oxide are highly variable. Water vapour mixing ratios between 0.2 ppm and 10 ppm were observed. The nitric oxide peak densities varied by more than a factor of ten. Maximum values of 2 × 10⁹cm⁻³ were obtained.     

The role of stratospheric minor warmings in producing the total ozone deficiencies over Europe in 1992 and 1993

During 1992 and 1993, record low total ozone values were observed over the middle and high northern latitudes. The ozone data from the long-operating station at Belsk, Poland, have been used to examine their departures from climatological behaviour in 1992 and 1993. It seems that not only do the exceptionally low ozone amounts recorded over the northern mid-latitudes need an explanation but also their occurrence for two years in a row. One of the possible mechanisms which may be responsible for this event is suggested to be connected with the occurrence of stratospheric minor warmings. They occur without a breakdown of the polar vortex but only with the displacement of very cold air towards lower latitudes (as in January 1992 and February 1993). It is known that air masses in the polar vortex have been chemically disturbed and, when they arrive over the sunlit middle latitudes, chemical destruction of ozone is likely to occur. During the periods under study, the strongest negative total ozone deviations correspond to strong negative temperature deviations at 30 hPa and to large potential vorticity values; this points to the presence over Europe of air masses of polar vortex origin. It has been shown that the characteristics of mid-winter stratospheric warmings and the interannual variability of winter-spring total ozone averages at Belsk are associated with each other.     

Revealing the city in maps: Bath seen, built, and imagined

Putting Bath on the Map is an exhibition of maps of the City of Bath displayed in the Building of Bath Collection. The maps are considered in the context of the permanent collection of the museum which examines how buildings were constructed in the eighteenth-century city. The exhibition reviews how buildings moved from conception, as shown on maps and in architectural texts, through legal, financial, and material processes to take their place in the landscape. This essay considers the display of particular maps, such as Joseph Gilmore's (1694), and John Wood's (1735), and the recent city initiative to improve its signage maps to help visitors and citizens build mental maps of the historic city.     

The photochemical time constants of minor constituents and their families in the middle atmosphere

A comprehensive formula is worked out for the photochemical time constant of minor constituents in the middle atmosphere. The formula is particularly useful for evaluating the time constants for families of some chemical species that are strongly coupled by rapid exchange reactions. Height profiles of photochemical time constants are calculated for individual species and their families based on the chemical reaction rate constants recommended in the recent WMO and JPL reports. Potential exchange reactions among various family members are discussed, and the effects of the choice of family membership on the time constant are evaluated.     

Network Autocorrelation in Transport Network and Flow Systems

The use of Moran's I to assess the existence of network autocorrelation in flows over the arcs of real (tangible) and abstract (intangible) networks is examined. Residuals of a migration model developed here reveal the presence of such autocorrelation or dependence. Two approaches for removing the observed dependence are examined.     

Transport Infrastructure and Regional Integration in the Middle East

The soft aspects of the infrastructure of regionalism in the Middle East have previously been studied, while the impact of the region’s hard infrastructure, in particular transport infrastructure, has received little attention. This paper contributes to the study of regionalism in the Middle East by investigating the relationship between hard infrastructure and economic integration. It analyzes whether the state of domestic and cross‐border transport infrastructure in the region promotes regional trade. This is done by addressing the following sub‐questions: 1) What is the condition of domestic and cross‐border transport infrastructure in the Middle East? And 2) What is the relationship between domestic and cross‐border transport infrastructure and regional trade in the Middle East? These questions are answered by examining Egypt, Iraq, Israel, Jordan, Lebanon, Palestine, Syria, and Turkey as representative samples of the broader region. It is argued that regionalism relies on the development of domestic and cross‐border transport infrastructure and where the latter is limited, regionalism cannot deepen. The study concludes that domestic and cross‐border transport infrastructure performance is weak in several of the countries studied and that this weakness hinders regional economic integration regardless of the level of the region’s soft infrastructure.     

Remote Runways: Air Transport and Distance in Tonga

Air transport brings areas 'closer together'. But it leaves some places relatively more isolated than when all depended on other modes of transport. Improved technology accentuates this tendency. Where traffic is low and distance long, the maintenance of links is costly. These issues are examined at both international and national scales in the case of Tonga, using several measures of distance and relative accessibility.     

Being seen in your pyjamas: the relationship between fashion,class, gender and space

Over the last decade class has re-emerged as a significant concept within British sociology, with prominent academics calling for a more Bourdieuian approach which focuses on class distinctions in cultural practices and tastes. Within this discussion, several note the important role fashion plays as a means of class distinction, though few have fully explored just how the fashion–class relationship operates. Based on empirical research, carried out as part of qualitative study into fashion practices and fashion discourse, this article examines the fashion–class relationship, by considering its links to both gender and space. It argues that the way in which women judge visibility and public space differs with class status and that this, in turn, has significant implications for women's fashion choices, and more specifically, dressing up. Indeed, whilst middle-class participants tend to view almost any space as public and one in which they are visible, for working-class participants neighbourhood and local spaces are seen to constitute semi-private spaces, whose audiences' opinions and judgements do not matter. As a result, being dressed in your pyjamas is not deeply problematic for these working-class women in the context of their everyday lives, whilst for their middle-class counterparts being seen in your pyjamas is something which should be avoided, at all cost. Moreover, as the article demonstrates, the wearing of pyjamas is often considered by middle-class respondents as indicative of working classness. And thus, being seen in your pyjamas is undesirable on two counts.     

A Comparison of Spatial and Nonspatial Methods in Statistical Modeling of NO2: Prediction Accuracy,Uncertainty Quantification,and Model Interpretation

${\text{NO}}_2$ is a traffic-related air pollutant. Ground ${\text{NO}}_2$ monitoring stations measure ${\text{NO}}_2$ concentrations at certain locations and statistical predictive methods have been developed to predict ${\text{NO}}_2$ as a continuous surface. Among them, ensemble tree-based methods have shown to be powerful in capturing nonlinear relationships between ${\text{NO}}_2$ measurements and geospatial predictors but it is unclear if the spatial structure of ${\text{NO}}_2$ is also captured in the response-covariates relationships. We dive into the comparison between spatial and nonspatial data models accounting for prediction accuracy, model interpretation and uncertainty quantification. Moreover, we implement two new spatial and a nonspatial methods that have not been applied to air pollution mapping. We implemented our study using national ground station measurements of ${\text{NO}}_2$ in Germany and the Netherlands of 2017. Our results indicate heterogeneous levels of importance of modeling the spatial process in different areas. The prediction intervals predicted with ensemble tree-based methods are more satisfactory than the geostatistical methods. The two new methods implemented each obtained better prediction accuracy compared to the original ensemble tree-based and stacking methods. The probabilistic distribution of the spatial random field estimated by the geostatistical methods could provide useful information for analyzing emission sources and the spatial process of observations.     

论上海旅游集散中心的形成与发展

上海旅游集散中心开创了散客旅游的一种组织模式。是散客旅游需求的扩张为散客接待服务的专业化提供了必要条件,专业化程度的提高又导致企业与企业纵向一体化的发展。     

从简帛看秦汉乡里组织的经济职能问题

经济剥削是秦汉乡里基层行政组织所要承担的主要职能,但不是唯一的经济职能.此外,还有其他诸多经济职能,比如国家维护小农经济稳定与发展的经济措施,乡官里吏都是具体的执行者.乡里社会自身日益复杂的经济事务,基层吏员也有解决与处理的职责,从而构成了封建国家乡里组织设立的另一重要原因.以此为视角,对我们客观看待封建国家政治权力与社会经济的关系不无益处,对我们全面理解乡里基层权力的结构与性质或许有些启示.     

The Transport Industry in the West and East Zones of the USSR

The levels of development of production and transportation are compared for the western and eastern zones of the USSR. The low density of the transport net in the East, combined with the high cost of transport construction and a manpower shortage, tends to favor the development of large industrial complexes within limited areas making use of the zone's unique natural resource base. Such areally concentrated development would reduce the need for local transport systems and make more investment available for the more efficient mainline routes. The western zone, with its virtually continuous economic development and denser transport net, favors a more uniform location of production and the increasing location of industry in small and middle-size cities, which would ease the load on heavily used mainline transport routes and make greater use of local forms of transportation, including motor freight.     

金文所见商周逢国相关史实研究

20世纪七八十年代,在山东济阳姜集乡刘台子墓地相继发现并发掘了几座西周时期墓葬,发掘者对其年代与族属进行了考订,初步认定该墓地属文献所载姜姓逢国所有。随后,有学者对其中几座墓葬的年代与墓主身份作了进一步讨论,商周逢国的历史问题也不断受到关注。然而,     

The Strategic Choice of Location and Transport Mode in a Successive Monopoly Model

This work emphasizes the incentives for vertical integration in a spatial model. A downstream monopoly will both strategically increase its transport costs and locate inefficiently relative to its customers. This forces the upstream monopolist to lower its input price rather than permit sales to decline. The excess costs and the inefficient location lower total profit in the vertical stream generating an incentive for vertical integration.     

Performance and Risks of Salt-Accumulating Renders in Relation to Their Moisture Transport Properties

Salt-accumulating renders are usually applied in several layers with different specific properties of moisture transport. An extensive experimental programme was carried out to establish a relationship between those properties of individual layers and the performance of combined systems on a salt-laden substrate. Each of the 20 renders was characterized separately in absorption and drying tests, vacuum saturation tests, dry cup tests, mercury intrusion porosimetry, and ultrasound wave velocity measurements. Each of the 12 combined render systems was applied on a brick, which was then saturated with a concentrated NaCl solution by free capillary uptake. Subsequently the assembly was closed at the bottom and subjected to an accelerated drying test (50° C and 15% relative humidity). Moisture and salt profiles over the depth were taken regularly during 1 month. The results reveal very different degrees of effectiveness and levels of risk for the substrate, which are related to the moisture transport properties.