208 research outputs found
Production of Gas Bubbles in Reduced Gravity Environments
In a wide variety of applications such as waste water treatment, biological reactors, gas-liquid reactors, blood oxygenation, purification of liquids, etc., it is necessary to produce small bubbles in liquids. Since gravity plays an essential role in currently available techniques, the adaptation of these applications to space requires the development of new tools. Under normal gravity, bubbles are typically generated by forcing gas through an orifice in a liquid. When a growing bubble becomes large enough, the buoyancy dominates the surface tension force causing it to detach from the orifice. In space, the process is quite different and the bubble may remain attached to the orifice indefinitely. The most practical approach to simulating gravity seems to be imposing an ambient flow to force bubbles out of the orifice. In this paper, we are interested in the effect of an imposed flow in 0 and 1 g. Specifically, we investigate the process of bubble formation subject to a parallel and a cross flow. In the case of parallel flow, we have a hypodermic needle in a tube from which bubbles can be produced. On the other hand, the cross flow condition is established by forcing bubbles through an orifice on a wall in a shear flow. The first series of experiments have been performed under normal gravity conditions and the working fluid was water. A high quality microgravity facility has been used for the second type and silicone oil is used as the host liquid
What influences women’s contraceptive choice? A cross-sectional study from Turkey
Objectives: In our study, we tried to investigate the determinants of women’s choices about contraception with the aim of discovering whether or not there is a difference in their preferences before and after consultation with a gynaecologist.
Material and methods: A total of 1058 women were enrolled. They were given detailed information regarding contraception and contraceptive methods. Subsequently, a survey which was made of 21 questions was administered.
Results: Contraceptive counselling significantly changed the contraceptive choice of women. However, influences from social media and friends, their partners and religious belief affected their contraceptive choices. Significant differences in contraceptive choice were observed when women were categorized according to their marital status, education level, household income, age, and number of children.
Conclusions: Although contraceptive counselling influenced Turkish women’s choices, there were still other determinants like social media and input from outside sources such as clerics and husbands, which should be overcome
O papel do conhecimento tácito na adesão às normas sociais
This paper aims to contribute to the ongoing discussion on adherence to social norms. It considers insights from multiple research traditions in an effort to explain how individual learning and action are connected to social norms. One strand of philosophical tradition holds that non-representational learning and skillful coping carried out unconsciously are underestimated by both scientific and philosophical traditions. The present research combines this tradition with the literature on the evolution of social norms and suggests that experienced individuals in a society adhere to social norms better than novice agents do. We explain this phenomenon by unconscious and non-representational cognitive processes. This framework is then used to investigate population-level outcomes of individual learning.Keywords: adherence to norms, expertise, skillful coping.Este artigo tem como objetivo contribuir para a discussĂŁo em curso sobre a adesĂŁo Ă s normas sociais. Ele cosnidera insights de mĂşltiplas tradições de pesquisa em um esforço para explicar como a aprendizagem e a ação individuais estĂŁo conectadas Ă s normas sociais. Uma vertente da tradição filosĂłfica sustenta que a aprendizagem nĂŁo representacional e o enfrentamento hábil inconscientemente sĂŁo subestimados pelas tradições cientĂficas e filosĂłficas. A presente pesquisa combina esta tradição com a literatura sobre a evolução das normas sociais e sugere que os indivĂduos experientes em uma sociedade adiram Ă s normas sociais melhor do que os agentes novatos. Explicamos este fenĂ´meno por processos cognitivos inconscientes e nĂŁo representativos. Este quadro Ă© entĂŁo utilizado para investigar resultados de nĂvel individual da aprendizagem individual.Palavras-chave: aderĂŞncia Ă s normas, perĂcia, habilidades de enfrentamento
Identification of the income level needed for agricultural enterprises to achieve economic sustainability
This study aims to identify the income level required for agricultural
enterprises to achieve economic sustainability. The theory behind
the equation used to calculate a sustainable income is explained.
The ecological, technical, social and economic components of
sustainability in agricultural enterprises have been identified and
discussed and the importance of economic sustainability in terms
of achieving total sustainability has been emphasised. Economic
sustainability was divided into three components incorporating the
income needed to meet the cost of living and to address depreciation
and interest costs for the enterprise. Those enterprises that achieved
this income level were determined to be economically sustainable.
For this purpose, data was collected by using a face-to-face survey
method with 181 agricultural enterprises operating in Konya and
analysed in line with the purpose of the study. According to the results
of our analysis, it was observed that more than 150 enterprises were
not sustainable
Management Style at Turkish SMEs
Republic of Turkey is one of those countries where SMEs are flourishing and acting as a driving force of development. In this paper, we explore management style at Turkish SMEs. Being an intersection of eastern and western cultures and with the recent liberalization of domestic markets, we believe this exploration can lead to interesting results. In this paper authors take a glance at Turkish SMEs. We investigate the management style at Turkish SMEs. We have gathered data from 421 SMEs located in Republic of Turkey, using a previously developed questionnaire. This study is an exploratory one and no hypothesis is configured. There are significant results regarding management style of Turkish SMEs. Individuals are more likely to work within a group and formal organizational structures and management policies are implemented as SMEs grow larger.Â
Enhanced self-collimation effect by low rotational symmetry in hexagonal lattice photonic crystals
In this study, we present the design of a photonic crystal (PC) structure
with a hexagonal lattice, where adjustments to the PC unit cell symmetry reveal
an all-angle self-collimation (SC) effect. By optimizing opto-geometric
parameters, such as the rotational angle of auxiliary rods and adjacent
distances, we analyze the SC property in detail, leveraging group velocity
dispersion (GVD) and third-order dispersion (TOD) characteristics. We also
investigate the relationship between symmetry properties and their influence on
dispersion characteristics. Through symmetry manipulation, we gain a
comprehensive understanding of the underlying mechanisms governing light
collimation and confinement in the proposed configurations. The PC structure
with a symmetry group exhibits all-angle SC effect within the range of
and normalized frequencies, with a
bandwidth of . Further breaking the symmetry,
transforming from to group symmetry, enhances the SC bandwidth to
and reveals the perfect linear equi-frequency
contours (EFC) at two different frequency bands: all angle SC between
and normalized frequencies in the 4th
transverse magnetic (TM) band and between and
in the 5th TM band. Additionally, we propose a
composite/hybrid PC structure resembling group symmetry, where two
auxiliary rods are replaced by rectangular photonic wires with the same
refractive index and width equal to the diameter of auxiliary rods. This hybrid
structure exhibits an all-angle SC effect with an operating bandwidth of
, displays near-zero GVD and TOD performance
and offers enhanced robustness against potential fabrication precision issues
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