Internal structure of the equatorial ionospheric dynamo

Using the Sq current profiles measured with rocket born magnetometer, off the coast of Peru, by Daviset al. (J. geophys. Res. 72, 1845) comparison is made between measured and calculated profiles near noon on geomagnetic dip equator, and a mismatch is pointed out in the height pattern of Sq current. Theory is worked out to determine the eastward electric field (E_y) with which computed j_y (eastward current density) coincides with the observed one. It is found that the neutral wind plays very important rôle in keeping E_y height-independent. E_y is found to be about 0.6 mVm⁻¹, ranging from 0.5 to 0.7 mVm⁻¹ in some cases. Flow of meridional current is obtained and its effect on jet current construction is discussed.     

Middle atmosphere electrical structure during MAC/EPSILON

Extensive use of rocket-launched probes during the MAC/EPSILON campaign at the Andøya Rocket Range, Norway, has enabled the characterization of the region's electrical environment for all four flight series. The first rocket salvo was conducted during daylight (15 October 1987) and the subsequent three occurred at night (21 and 28 October and 12 November 1987), all of them during geomagnetically disturbed conditions. Measurements of polar electrical conductivity, ion mobility and number density are presented, and their associated structure is investigated for local auroral ionization effects. This is believed to be the first time that Gerdien condenser mobility measurements have indicated a heavy-ion presence (positively charged aerosols) in the auroral mesopause region.     

Archaeopedological analyses around a Neolithic hearth and the beginning of Sabaean irrigation in the oasis of Ma'rib (Ramlat as-Sab'atayn,Yemen)

Archaeopedological analyses in the oasis of Ma'rib (Yemen) yield new information of Neolithic land use, Bronze Age soil formation, and Sabaean irrigation. The AMS radiocarbon age of a Neolithic fireplace buried under Sabaean irrigation sediments in the Southern oasis indicates Pre-Sabaean human activities in Wadi Dhana about 5600 years ago. The associated Mid-Holocene palaeosol, developed in fluvial sediments of Wadi Dhana and also in the filling of the hearth, marks the Bronze Age-land surface before it was covered with irrigation sediments. Based on AMS radiocarbon data from charcoal in reservoir sediments of the “Great Dam” and an estimated time span of pedogenesis of the Mid-Holocene palaeosol in this region, we propose the beginning of the irrigation in Ma'rib in the period of 2500–1000 cal yr BC.     

Petrological characterisation of 'alabaster' from the Marib province in Yemen and its use as an ornamental stone in Sabaean culture

'Yemen alabaster', a calcareous sinter, is a unique building and ornamental stone of the Sabaean culture ( c. 1000 BC to 100 AD). This study characterises the quarries and describes the facies of their stones. Through thin sections, luminescence microscopy and geochemical analyses, 'Yemen alabaster' can be classified and assigned a quarry source. The stone is a calcareous sinter related to volcanism in the Marib province. It can be divided into several microfacies types different in luminescence and trace element contents. During Sabaean times it was mined in highly organised quarries including underground quarries and used extensively in the Sabaean kingdom.     

The Neronian and the historical structure of cultural shifts from Middle to Upper Palaeolithic in Mediterranean France

The end of the Middle Palaeolithic period can be considered a key moment in the history of humanity, characterized by profound changes in traditional Palaeolithic societies. Whatever the reasons for this historical change, it seems well established that it took place within a particularly dynamic phase of these societies, when Upper Palaeolithic technical processes were already emerging. The analysis of recent Mousterian industries in Mediterranean France highlights certain points of inflection, which presage new ways of life. The analysis of key sites demonstrates important transformations within the last Neanderthal societies, with a gradual rearticulation of Mousterian technical systems around the production of blades and points and with profound changes in the relationship of the craftsman with his tools. Even if they are typical of the late Mousterian more generally, these technically distinctive industries have such distinct chronological, territorial and cultural characteristics that they can be referred to by a specific name, the “Néronien” (Neronian). Stratigraphically speaking, this group of assemblages – at the crossroads of the Middle and Upper Palaeolithic – appears in some important regional sequences just before the appearance of the first “true” Upper Palaeolithic industries (the Protoaurignacian). However, this Neronian doesn't represent the end of the Middle Palaeolithic period in the Rhône valley. The final Moustérien of this region is actually marked by deep breakdowns of the traditional balances in the human groups. This second point of inflection could characterize a true destabilization of Mousterian societies. There is an interesting parallelism between the historical paths of the Castelperronian in the arch of the Massif Central and the Neronian in the Rhône valley. It also highlights the mosaic nature of the profound cultural changes that occurred at the end of the Middle Palaeolithic.     

Middle atmosphere tides

Recent progress in the study of middle atmosphere tides is reviewed. Specific areas where recent progress has occurred include: development of more realistic thermal excitation and numerical simulation models; the role of tides in accelerating and heating the mean flow at the base of the thermosphere; observational efforts which delineate average seasonal, latitudinal and vertical structures of tides, and shorterterm variations of tides about these values; theoretical and observational studies concerning the importance of non-migrating tidal components; the effects of tides on minor constituent concentrations in the upper mesosphere and lower thermosphere. The review concludes with a summary of key problems to be addressed in the future.     

内部营销和内部服务质量对外部服务质量的影响

管理人员应明确员工的工作任务、评估员工的服务质量、指导员工工作、关心员工、高度重视员工培养工作,各个职能部门之间的相互服务质量、员工之间的相互服务质量都会直接或间接地影响宾馆的外部服务质量。作根据数据分析结果,对宾馆管理人员如何加强内部服务质量管理提出了一系列建议。     

武卫中军与《谕武卫中军告示》

武卫中军是晚清武卫军中唯一一支经奏准招募的军队,是武卫军总统荣禄的亲军。该军虽然营制较新,饷章较丰,武器配备较先进,但军官缺乏统领新军的能力和水平,训练、教育方式方法落后,兵源构成复杂,训练、教育时间较短,使得其在镇压义和团运动和抗击八国联军入侵的活动中,表现出了极差的军风、军纪和作战能力。因而,它也是武卫军中成军最晚、裁撤最早、军纪最坏、练兵最不成功的一支军队。《谕武卫中军告示》有助于我们了解该军的一些背景、训练和教育的情况。     

中世纪中后期法兰西王室守护神问题探析

在古代社会乃至在某些传统情结较为浓厚的现代社会,一定的社会群体往往会将某一具有特殊地位的超自然神灵(或神化了的历史人物)奉为自己的守护神,以此求得精神上的安慰与寄托。对于这一特定的社会群体来说,守护神选定以后,其角色通常会呈现出既定性和恒常性特征,一般不会因时间的推移而轻易出现其角色由他神取而代之的现象。然而,     

Beijing Tibet Middle School

The year marks the 20th anniversary of the Central Government decision to run Tibet middle schools in the hinterland. At present, there are such schools or Tibetan classes in 26 provinces and municipalities directly under the Central Government. They work to train technical personnel and teachers for Tibet. Launched in 1987, the Beijing Tibet Middle School has since trained more than 2,800 middle and high school students for Tibet. Many of them returned to Tibet for construction.