ساینس دایرکت یکی از 79 محصول آنلاینی است که شرکت الزیور در اختیار پژوهشگران و محققین، دانشجویان، اساتید و کلیه علاقه مندان به علم و دانش قرار می دهد. این مجموعه حدود 4 میلیون مقاله علمی با موضوعات بسیار متنوع از سال 1995 تا کنون فراهم کرده است.

اگرچه تمرکز اصلی پایگاه علمی Sciencedirect (ساینس دایرکت) بر علوم پایه، فنی و پزشکی می باشد، اما تعداد بسیار زیادی مقاله و ژورنال با موضوعات علوم انسانی و اجتماعی نیز موجود می باشد.بنابر این نام Science Direct تا حدودی گمراه کننده می باشد. به طور کلی ژورنال ها در چهار گروه اصلی طبقه بندی شده اند : علوم فیزیکی و مهندسی، علوم زیستی، بهداشت و سلامت، و علوم اجتماعی و انسانی.

بخش اعظم ژورنال های انتشار یافته در این پایگاه داده توسط موسسه علمی (تامپسون رویترز) نمایه گذاری می شود، بنابر این اغلب مقالاتی که از این پایگاه داده دانلود شده است، جزو مقالات آی اس آی(ISI) محسوب می شوند.

از امکانات پایگاه علمی ساینس دایرکت می توان به هشدارهای جستجو اشاره کرد که به محض افزوده شدن مقاله ای مرتبط با مقاله انتخاب شده توسط شما در پایگاه داده، اعلانی به شما ارسال می گردد.

به صورت خلاصه مجلات، مقاله های علمی و کتاب های موجود در پایگاه علمی ساینس دایرکت (Sciencedirect)، حوزه های علمی زیر را تحت پوشش دارد :

علوم مهندسی: مهندسی شیمی، علوم کامپیوتر، انرژی، علم مواد، ریاضیات، فیزیک و نجوم

علوم زیستی: بیوشیمی، ژنتیک و زیست شناسی مولکولی، محیط زیست، ایمونولوژی و میکروب شناسی

بهداشت و سلامت: علوم دارویی، دامپزشکی، پزشکی و دندانپزشکی

علوم اجتماعی و علوم انسانی: هنر، کسب و کار، مدیریت، حسابداری و اقتصاد، روانشناسی ، علوم اجتماعی

چه کسانی از پایگاه علمی ساینس دایرکت (ScienceDirect) بهره می برند:

خواه هدف از اکتشاف و تحقیق پیشبرد یک پروژه خاص یا رسیدن به یک نتیجه جدید برای ارتقا علم باشد، همه اینها نیازمند و وابسته به داشتن منابع مناسب علمی هستند. ساینس دایرکت (Science Direct) به عنوان یک راه حل هوشمندانه با ترکیبی از نشریه ها ومقاله های علوم پایه، فنی و پزشکی به کاربران خود این توانایی را می دهد که در تحقیق، آموزش و مطالعات خود موفق تر و موثرتر باشند.

Recent financial turmoil (e.g., the 2008–2009 global financial crisis) has resulted in financial contagion-induced instability becoming one of the major concerns in the fields of economics and finance. In this paper, we extend the network analysis of financial contagion from three perspectives. First, given that cross-holding of claims and obligations among financial institutions can be viewed as input-output linkages, we model the financial system and the contagion mechanism by introducing the classic Leontief input–output framework. Second, based on this modeling process, we propose a simple contagion algorithm to study how financial system heterogeneity influences its stability. Third, to mitigate financial contagion, we propose several concrete intervention policies based on two widely used prudential approaches—forced mergers and capital injections. The performance of these intervention policies is then evaluated by comprehensive numerical experiments. Our study has significant implications for financial regulation and supervision.

We examine whether firms respond to settlements of their uncertain tax benefits (UTBs) by adjusting the related UTB reserve. A reported UTB settlement indicates that the tax authority challenged at least one of the firm’s uncertain tax positions, thereby providing information to managers regarding the sustainability of similar tax strategies and outstanding UTBs. Consistent with expectations, our results suggest that UTB settlements are negatively related to the accrual for new uncertain tax positions. Further, we demonstrate that managers make less downward adjustments to the UTB reserve related to existing uncertain tax positions following settlements with tax authorities. Finally, additional analysis suggests that the valuation of UTBs is lower in the year subsequent to a UTB settlement. Collectively, our results suggest that the information gathered from tax audit outcomes influences firms to be more conservative in their tax reporting, and possibly their future tax planning as well.

To mitigate climate change, low-carbon economy is introduced as a sustainable development strategy. Natural gas, as an alternative to pollutant fuels such as coal, which is now widely used, could facilitate global transition to the age of renewable energy. Iran is one of the major emitters of CO₂ in the world, and it is thus, crucial to move toward low-carbon economy in order to accomplish its commitment in reducing GHG emissions. This study evaluates Iran’s natural gas industry development by reviewing reserves, production and consumption, infrastructures as well as natural gas agreements. The total proven natural gas reserves of Iran is estimated 33500 bcm by the end of 2015, where more than 60% of them are offshore. There exists 23 active fields in Iran and the largest of which is South Pars gas reservoirs in the Persian Gulf. The gross production of natural gas was 257623 million cubic meters in 2015 of which 80% was marketed. The current state of Iran’s natural gas industry is assessed as an acceptable level due to massive reserves, high production capacity, wide transmission and distribution network and high penetration of natural gas in cities and villages. That is why natural gas has the highest contribution in the national energy mix, resulting in replacing petroleum fuels with natural gas to decrease CO₂ emissions. However, in recent years, delays in implementing development projects of the natural gas industry made supplying domestic demand difficult during cold seasons. Furthermore, it negatively influenced the nation’s gas export potential. Iran’s natural gas industry faces some challenges including growing domestic demand, high energy loses in residential and commercial sectors and low efficiency of energy systems in industrial and power generation sectors. If challenges are solved, natural gas could serve as a bridge for transition toward the low-carbon future of Iran.

While financial inclusion is typically addressed by improving the financial infrastructure, we show that a higher degree of financial literacy also has a clear beneficial effect. We study this effect at the cross-country level, which allows us to consider institutional variation. Regarding “access to finance”, financial infrastructure and financial are mainly substitutes. However, regarding the “use of financial services”, the effect of higher financial strengthens the effect of more financial depth. The causal interpretation of these results is supported by IV-regressions. Moreover, the positive impact of financial holds across income levels and several subgroups within countries.

As the resource tax will be extended to the occupation of natural ecological space in China, this paper takes Shanxi Province as an example to calculate the ecological footprint and ecological service value of energy consumption; it then constructs a Computable General Equilibrium model of tax on ecological occupation and analyzes the impact of resource tax reform on a resource-based economy from the structure of factor, output, and trade. The results show that the tax scheme has an obvious effect on promoting economic transition under a static situation, but it also has a greater negative impact. In a dynamic scenario, the negative effect is small, but it affects long-term economic growth. In terms of factor structure, ecological footprint steadily declines, while investment growth is rapid. In terms of output structure, the proportion of the secondary industry increases, but the growth rate is slower, and the growth rate of the tertiary industry continues to improve. In terms of trade structure, although the coal mining industry shows increased export, the growth rate is declining, and there is increase in net exports of tertiary industry. Thus, the tax scheme has the effect of promoting the transformation of a resource-based economy. We propose levying a resource tax based on ecological occupation to protect the ecological service function of natural resources, reduce the capital and labor factor tax, and promote the development of non-resource type industry.

We investigate whether accounting conservatism can be explained as a rational response to ambiguity. Decision analysis shows that decision rules that work well under ambiguity put greater weight on negative than on positive outcomes, i.e., exhibit caution. Accounting conservatism increases the timeliness of bad news that is more relevant under cautious decision rules and thereby helps corporate managers and investors implement them. We, therefore, hypothesize that firms facing greater ambiguity report more conservatively. We adopt two different measures to proxy for the firm-specific level of ambiguity. First, we identify firms pursuing the “prospector” versus “defender” business strategies. Compared with defenders, who focus on utilizing existing resources, prospectors actively create their future by seeking new business opportunities and thus face greater ambiguity. Second, we conduct an additional set of tests based on environmental scanning, which reduces ambiguity. Both sets of results suggest that firms facing greater ambiguity report more conservatively.