Wave breaking on turbulent energy budget in the ocean surface mixed layer

As an important physical process at the air-sea interface, wave movement and breaking have a significant effect on the ocean surface mixed layer (OSML). When breaking waves occur at the ocean surface, turbulent kinetic energy (TKE) is input downwards, and a sublayer is formed near the surface and turbulence vertical mixing is intensively enhanced. A one-dimensional ocean model including the Mellor-Yamada level 2.5 turbulence closure equations was employed in our research on variations in turbulent energy budget within OSML. The influence of wave breaking could be introduced into the model by modifying an existing surface boundary condition of the TKE equation and specifying its input. The vertical diffusion and dissipation of TKE were effectively enhanced in the sublayer when wave breaking was considered. Turbulent energy dissipated in the sublayer was about 92.0% of the total depth-integrated dissipated TKE, which is twice higher than that of non-wave breaking. The shear production of TKE decreased by 3.5% because the mean flow fields tended to be uniform due to wave-enhanced turbulent mixing. As a result, a new local equilibrium between diffusion and dissipation of TKE was reached in the wave-enhanced layer. Below the sublayer, the local equilibrium between shear production and dissipation of TKE agreed with the conclusion drawn from the classical law-of-the-wall (Craig and Banner, 1994).

Effects of salinity on energy budget in pond-cultured sea cucumber Apostichopus japonicus (Selenka) (Echinodermata: Holothuroidea)

Pond farming for sea cucumber has developed rapidly along the northern coast of China in the recent years. Holothurians inhabiting ponds undergo seasonal fluctuations of salinity. This study deals with the bioenergetic responses of pond-cultured sea cucumbers Apostichopus japonicus (wet weight of 37.5 +/- 1.8 g) to different water salinities [22, 27, 31.5, and 36 practical salinity units (psu)] at 15 degrees C in the laboratory to determine the influence of water salinity on growth and energy allocation in this species. Results show that ingested energy and scope for growth (SFG) were highest at 31.5 psu and then decreased when water salinity was below or above this point. Although energy ingested was lowest at 36 psu, the lowest SFG occurred at 22 psu (only 102.68 +/- 14.26 J g(-1) d(-1)) because animals reared at 22 psu spent much more consumed energy on feces (72.19%), respiration (21.70%), and excretion (2.59%), leaving less energy for growth (3.52%). Results suggest that pond-cultured sea cucumbers could tolerate chronic salinity fluctuations at a range of 22 to 36 psu and grew better between 27 and 31.5 psu, but decreased at salinities above and below the mentioned salinity range. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.

Direct Numerical Simulation of Shock/Turbulent Boundary Layer Interaction in a Supersonic Compression Ramp

A direct numerical simulation of the shock/turbulent boundary layer interaction flow in a supersonic 24-degree compression ramp is conducted with the free stream Mach number 2.9. The blow-and-suction disturbance in the upstream wall boundary is used to trigger the transition. Both the mean wall pressure and the velocity profiles agree with those of the experimental data, which validates the simulation. The turbulent kinetic energy budget in the separation region is analyzed. Results show that the turbulent production term increases fast in the separation region, while the turbulent dissipation term reaches its peak in the near-wall region. The turbulent transport term contributes to the balance of the turbulent conduction and turbulent dissipation. Based on the analysis of instantaneous pressure in the downstream region of the mean shock and that in the separation bubble, the authors suggest that the low frequency oscillation of the shock is not caused by the upstream turbulent disturbance, but rather the instability of separation bubble.

Annual cycle of stratification and tidal fronts in the Bohai Sea: A model study

In general, competition between buoyancy mechanisms and mixing dynamics largely determines the water column structure in a shelf sea. A three dimensional baroclinic ocean model forced by surface heat fluxes and the 2.5 order Mellor-Yamada turbulence scheme is used to simulate the annual cycle of the temperature in the Bohai Sea. The difference between the sea surface temperature (SST) and sea bottom temperature (SBT) is used to examine the evolution of its vertical stratification. It is found that the water column is well-mixed from October to March and that the seasonal thermocline appears in April, peaks in July and then weakens afterwards, closely following the heat budget. In addition, the Loder parameter based on the topography and tidal current amplitude is also computed in order to examine tidal fronts in the BS, which are evident in summer months when the wind stirring mechanism is weak.

Rhinopithecus bieti at Tacheng, Yunnan: Diet and daytime activities

We collected data on diet and activity budget in a group of Rhinopithecus bieti at Tacheng (99degrees 18'E, 27degrees 36' N, between 2,700 - 3,700 m asl), Yunnan, from March 1999 to December 2000. We mainly recorded species-parts eaten with feeding scores from scanning state behaviors of one-male units in tree-crowns. We also conducted microscopic analysis of feces collected monthly. The subjects consumed 59 plant species, belonging to 42 genera in 28 families, of which 90 species-parts were distributed as follows: 21 in Winter, 38 in spring, 39 in Summer, 47 in autumn. Conversely, the group annually spent, on average, 35% of daytime feeding, 33% resting, 15% moving, and 13% in social activities. Seasonal changes are apparent in daytime budget and food item-related feeding time in tree-crowns, food remains in feces, and the number of species-parts eaten. Correlations within and between food items and time budget clearly indicate maximization of foraging effectiveness and minimization of energy expenditure. In consideration of reports from northern and southern groups, that which underlay the specific adaptation to the habitat appeared to be similar to those of other colobines. Thus, the ultimate factors for survival of the species are more hopeful than expected.

商务智能中数据分析代理(DAA)模式的研究与实践

在介绍了数据分析代理的概念后,提出了数据分析代理模式的体系结构,讨论了在不同类型企业中数据分析代理的具体应用模式企业内代理模式和企业外代理模式,对比分析了数据分析传统模式和代理模式二者之间特点,最后举例说明了数据分析代理模式在企业中的具体实践。

道德强度对企业道德决策的影响及作用机制

Moral decision-making in business means the decisions involved in moral issues in business context. Moral intensity is a construct that captures the extent of issue-related moral imperative in a situation, which is one of the most important factors in the study of moral decision-making in business. Based on Issue-Contingent Model, the present study investigated the influence of moral intensity on moral decision-making in business (including moral recognition, moral judgment, and moral intent in the present study), and further focused on exploring the mechanism of moral intensity in moral decision-making in business. Recently, the studies in decision-making gave more emphasis to the role of emotions. The present study tried to include empathy into moral decision-making in business to explore the role of empathy in the relationship between moral intensity and moral decision-making in business, which would enrich and extend Issue-Contingent Model. The present study would also make up for a deficiency in the study of moral decision-making in business that overemphasized the rational reasoning and neglected the role of emotions. There were three parts in the present study. Firstly, study 1 replicated the former study and explored the relationship between perceived moral intensity and moral decision-making in business in China by questionnaire method. Secondly, study 2 focused on exploring the influence of the components of moral intensity on moral decision-making in business and empathic response by experimental method. Finally, study 3 explored the role of empathy in the relationship between moral intensity and moral decision-making in business. The results indicated that, 1.Perceived moral intensity was the significant predictor for moral decision- making in business. 2.Magnitude of consequence, social consensus, and probability of effect had significant effects on moral decision-making in business. Magnitude of consequence and probability of effect could influence empathic response significantly. 3.Empathic response played the role of mediator between moral intensity and moral decision-making in business. Empathic response completely mediated the relationship between moral intensity and moral recognition. Empathic response partly mediated the relationship between moral intensity and moral judgment, moral intent. Further analysis indicated that probability of effect and magnitude of consequence relied more on empathic response than social consensus to influence moral judgment and moral intent. Dispositional empathy could influence moral decision-making in business through perceived moral intensity and empathic response. 4.Controlled empathic levels could influence moral decision-making in business significantly. Empathic levels influenced the effect of probability of effect on moral decision-making in business, and did not influence the effect of magnitude of consequence and social consensus on moral decision-making in business. These findings not only contribute to enrich the models of moral decision- making in business, but also have significant practical applications in the training of moral decision-making in business.