20世纪涅瓦湾中的浮游生物群落

本研究论文综述了根据涅瓦湾和20世纪浮游生物群落发生的变化所作的浮游动植物研究.众所周知,浮游生物受水质变化,特别是有机质含量变化的影响.对文献资料的比较结果反映了物种作为不同状况的指标的价值.涅瓦湾中的许多浮游生物种显示出由于不同的环境状况而发生的年复一年的巨大变化.根据1911～1990年间进行的研究的结果,在涅瓦湾中,淡水浮游生物种占支配地位.浮游生物群落基本上包括从拉多加湖输送来的物种.半咸水种偶而出现在涅瓦湾的浮游生物样中.浊度大以及水的通流速度快限制了湾中藻类的生产,同时由于流出量大,集水区的富营养化影响主要被传导到芬兰湾中     

Computation of particles’ ascent from a cavity behind passing shock wave

We study numerically the dynamics of particles of dispersed phase in a turbulent gas flow in planar shock waves (SWs) sliding along a solid surface with a depression of trapezoid shape. The ascent of particles from the cavity walls has been computed in the approximation of a rarefied gas–particle mixture. A considerable influence of the passing SW strength and the initial location of particles on the characteristics of particles’ ascent, the non-monotonicity of the dependence of the particle-ascent height on the initial longitudinal coordinate, and the SW Mach number, and a possibility of the formation of particles’ accumulation and removal zones on the depression bottom are shown.     

Modeling of the long-term tropospheric trends of hydroxyl radical for the Northern Hemisphere

The MGO 2D (altitude–longitude) channel photochemical transport model has been applied to elucidate the spatial and temporal behavior of the hydroxyl radical in the troposphere of the northern temperate belt for the pre-industrial (1850) period and the last few decades (1960 and 1995). The relation between the tropospheric OH content and the carbon monoxide, methane, nitrogen oxides emissions during 1850–1995 is studied. The distribution of the carbon monoxide concentration is calculated and validated using the observational data collected in the different locations because of the geographical non-homogeneity of its emissions. The response of the hydroxyl radical concentrations to the non-homogeneity of the CO and other atmospheric species distribution is estimated. The carbon monoxide and methane contributions to the hydroxyl photochemical sink are also evaluated. Because the changes of OH in the troposphere alternate the intensity of methane and carbon monoxide oxidation, the CO, CH₄ and OH lifetime evolution due to the increase of anthropogenic pollution intensity is analyzed and discussed.     

Engineering meets institutions: an interdisciplinary approach to the management of resilience

Resilience management stretches across the decoupled domains of community, corporate, and public governance. As a result, fostering resilience needs a governance structure that supports collective actions and integrates fragmented fields with different institutional frameworks. In this study, we carry out a review of three different perspectives on resilience -engineering, social, and organizational- in order to explore resilience management in the context of governance of infrastructure systems. We discuss the common practices to address resilience of engineering systems, the need and current trend for integration of institutions into these practices through formal (e.g., policies and regulations) as well as informal mechanisms (e.g., trust, norms, and shared cognitive structures). To illustrate our theorizing, we provide three illustrative case studies. The cases highlight the barriers and enablers across the three perspectives and highlight the inter-organizational context of management of resilience. We uncovered organizational dynamics such as the necessity of establishing critical functionality through organizational capacity for stakeholder engagement, the need for diverse organizations to address institutional complexity in management of resilience, and the importance of decoupling in aligning the outcomes of resilience management practices with policies. We suggest an agenda for future research on managing practices associated with management of resilience.     

Worldviews,institutions and sustainability: An introduction to a co-evolutionary perspective

This work analyzes hierarchical and causal relationship between worldview, institutions, technology and economic behaviour under conditions of informational uncertainty.

In our pursuit of sustainable living, institutions function both as constraints and as primary instruments of change of socio-economic behaviour. The process of radical institutional change is contingent upon prior change in the dominant worldview, while its dynamics resembles that of a paradigm change in political and scientific arenas. Therefore, the timely and adaptive outcome of institutional change with respect to global environmental problems remains intrinsically uncertain.     

A performance-based tabular approach for joint systematic improvement of risk control and resilience applied to telecommunication grid,gas network,and ultrasound localization system

Environment Systems and Decisions - Organizational and technical approaches have proven successful in increasing the performance and preventing risks at socio-technical systems at all scales....