Modern aspects of sustainable development in context of global safety

The authors have considered modern scientific approaches to the problem of sustainable development of complex dynamic systems. Main factors of risks are generalized: anthropogenic, technogeneous and ecological. Some aspects of Darwin’s triad and the second law of thermodynamic are used to explain the problems of global safety.Автори розглянули сучасні наукові підходи до проблем сталого розвитку складних динамічних систем. Узагальнені головні фактори ризику: антропогенні, техногенні і екологічні. Деякі аспекти дарвінівської тріади та другий закон термодинаміки використані для пояснення аспектів глобальної безпеки.Авторы рассмотрели современные научные подходы к проблеме устойчивого развития сложных динамических систем. Обобщены главные факторы риска: антропогенные, техногенные и экологические. Некоторые аспекты дарвиновской триады и второй закон термодинамики использованы для объяснения аспектов глобальной безопасности

Recording the high efficient diffraction gratings by using He-Cd laser

High efficient holographic diffraction gratings with spatial frequencies from 600 to 3600 mm⁻¹ have been recorded using As₄₀S₆₀–хSeх (х = 0, 10, 20) photoresist layers and He-Cd laser operating at the wavelength λ = 440 nm. The investigation of the grating relief made by atomic force microscopy revealed that As₄₀S₆₀–хSeх resists allows one to record grating originals with profiles of various heights depending on the resist chemical composition, its etching and exposure times. We obtained typical spectral and angular dependences of the first order diffraction efficiency for the grating with the high modulation depth and groove profile close to the sinusoidal one. Comparing the recorded gratings with different spatial frequencies, exposure and etching times, we determined optimal recording conditions (exposure and etching times) in order to obtain gratings with the high diffraction efficiency