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21.
Japan's future trajectory in security policy and the extent of deviation from the post-war course of a constrained military stance have been the source of constant academic and policy debate. Japanese policy-makers have maintained that national security policy has shown no fundamental deviation, and that this can be benchmarked against a range of constant anti-militaristic principles. The advent of BMD, however, poses significant questions over whether Japan is continuing to follow a similar security trajectory. This article examines how BMD has challenged four key anti-militaristic principles—the non-exercise of collective self-defence, the non-military use of space, the ban on the export of weapons technology, and strict civilian control of the military—and uses this assessment to judge how BMD is driving remilitarisation. It concludes that BMD's impact is highly significant in transgressing these anti-militaristic principles and is thus indicating a more remilitarised security path for Japan developing now and in the future.  相似文献   
22.
Meteorites are being retrieved from the surface of our planet all the time, the number of located falls being at maximum in the range 0.3 to 1.0 yr-1 (106 km2)-1. Using the known flux of meteorite parent bodies to the top of the atmosphere this paper reviews suggested ablation processes and predicts the actual flux of meteorites to the Earth. It is found that this is some 70 to 300 times what is observed.  相似文献   
23.
Substorm onsets, identified by Pi2 pulsations observed on the AFGL Magnetometer Network, have been studied using ISEE 1 electric and magnetic field data and GOES 2 and GOES 3 magnetic field data. The relative positions of the spacecraft with respect to the substorm current system were determined from the Pi2 polarizations. One onset occurred when ISEE 1 and GOES 2 were on the same field line but in opposite hemispheres. During this onset ISEE 1 and GOES 2 observed magnetic signatures which appear to be due to conjugate field-aligned-currents flowing out of the western edge of the westward electrojets. A broadband burst of wave noise was seen in the ISEE 1 electric field at the same time as field-aligned-currents were observed. These may be current driven ion cyclotron waves. A three minute perturbation in the electric field data prior to the initial substorm onset indicates that there was an azimuthal westward flow of plasma starting ~ 1 min before the substorm onset.  相似文献   
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