Multielement systems of double slots in rectangular waveguide with partial dielectric filling
Resonance characteristics of narrow transversal slots, energetic and directional characteristics of an antenna array (AA) with single transversal slots and double ones cut in a rectangular waveguide, partially filled with dielectric are investigated. In the case of the single transversal slots and double transversal slots a dielectric layer is parallel to broad walls of the waveguide. It was shown the possibility to construct an AA with double transversal slots the pattern without diffraction lobes and high level of radiation power in the frequency band.
Successive approximation method for the linear system of double longitudinal slots in a rectangular waveguide
An efficient approximation method is used to calculate energetic parameters and amplitude-phase distribution along a linear waveguide-slot antenna with double longitudinal slots in a broad wall of a rectangular waveguide having an arbitrary end loading. The approach is used when the E-field in slots is approximated with only one sinusoidal function. The mutual coupling of the slots over a waveguide and free space is taken into account, as well as the thickness of a waveguide wall and dielectric filling of the slots.
Protection of the Marine Environment: The International and National Regulation of Deep Seabed Mining Activities
This chapter provides an overview of the international and national regulatory framework pertaining to deep seabed mining activities. It begins by discussing the UN Convention on the Law of the Sea, the backdrop for all marine activities – be they national or international – and examines the obligations of states to protect the marine environment from the harmful effects arising from deep seabed mining. Next, the chapter examines the international regime for deep seabed mining (i.e. “activities in the Area”), explaining the “common heritage of mankind” status of the Area (i.e. the international seabed); the functions of the International Seabed Authority (ISA), the international organization established to govern deep seabed mining in the Area; and the concept of state sponsorship of non-state entities (i.e. private actors) for deep seabed mining in the Area. The chapter follows with a discussion of the development of national legislation to regulate deep seabed mining, examining efforts in the Pacific region where many prospective deep-sea mining sites are located. This includes a look at the legislative regimes of several Pacific Island nations, namely, Papua New Guinea, Tonga and the Cook Islands, for whom deep seabed mining may soon become a reality – as well as New Zealand and Japan, countries with comparatively developed rule of law and legislative regimes that have undertaken or considered deep seabed mining in their national waters. Overall, the chapter critically describes and evaluates the current regulatory status in the international and national seabed areas and highlights some salient gaps that require urgent attention in order to ensure marine environmental protection and mitigate impacts on humans.