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Free-surface vortices have long been studied to develop an understanding of similar rotating flow phenomena observed in nature and technology. However, a complete description of its turbulent three-dimensional flow field still remains elusive. In contrast, the related Taylor-Couette flow system has been well explicated which classically exhibits successive instability phases manifested in so-called Taylor vortices. In this study, observations made on the turbulent free-surface vortex revealed distinguishable, time-dependent “Taylor-like” vortices in the secondary flow field similar to the Taylor-Couette flow system. The observations were enabled by an original application of 2D ultrasonic Doppler velocity profiling complemented with laser induced fluorescence dye observations. Additional confirmation was provided by three-dimensional numerical simulations. Using Rayleigh’s stability criterion, we analytically show that a wall bounded free-surface vortex can indeed become unstable due to a centrifugal driving force in a similar manner to the Taylor-Couette flow. Consequently, it is proposed that the free-surface vortex can be treated analogously to the Taylor-Couette flow permitting advanced conclusions to be drawn on its flow structure and the various states of free-surface vortex flow stability.

Laparoscopic splenectomy has been safely performed for small spleens, but technical limitations have prevented massive splenectomy. We describe a technique of early hilar devascularization to enable massive splenectomy in three patients over the age of 80 years. Massive splenectomy was performed with minimal blood loss and minor morbidity. Early laparoscopic control of the splenic artery and vein will enable the safe removal of the massive spleen, without major laparotomy. Morbidity of splenectomy may be reduced by laparoscopy.

Real‐time monitoring of water consumption activities can be an effective mechanism to achieve efficient water network management. This approach, largely enabled by the advent of smart metering technologies, is gradually being practiced in domestic and industrial contexts. In particular, identifying water consumption habits from flow‐signatures, i.e., the specific end‐usage patterns, is being investigated as a means for conservation in both the residential and nonresidential context. However, the quality of meter data is bivariate (dependent on number of meters and data temporal resolution) and as a result, planning a smart metering scheme is relatively difficult with no generic design approach available. In this study, a comprehensive medium‐resolution to high‐resolution smart metering program was implemented at two nonresidential trial sites to evaluate the effect of spatial and temporal data aggregation. It was found that medium‐resolution water meter data were capable of exposing regular, continuous, peak use, and diurnal patterns which reflect group wide end‐usage characteristics. The high‐resolution meter data permitted flow‐signature at a personal end‐use level. Through this unique opportunity to observe water usage characteristics via flow‐signature patterns, newly defined hydraulic‐based design coefficients determined from Poisson rectangular pulse were developed to intuitively aid in the process of pattern discovery with implications for automated activity recognition applications. A smart meter classification and siting index was introduced which categorizes meter resolution in terms of their suitable application.

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Hydraulic structures are critical for water management. Yet many structures continue to be neglected, in poor condition, and inadequate in adapting to evolving societal challenges associated with shifting climatic events and population growth. In this context, hydraulic structures engineering should be moving from traditional design considerations toward sustainability, that is, continuing to meet current and future social, environmental, and economic needs. This requires this community to embrace and help advance global and multidisciplinary perspectives. Therefore, this article presents the authors' point of view on current trends, concerns, and needs related to hydraulic structures engineering. Furthermore, the authors propose a new, forward‐looking framework for the consideration of the hydraulic structures community that is grounded on the evolution of interconnected research tools and methodologies in addition to emphasizing and bolstering strong links between academia and industry. The evolution of this framework has naturally originated from the pervasive challenge of validating the design and operation of hydraulic structures in the field for frequent and extreme conditions. The authors suggest that future developments of hydraulic structures engineering require (a) continuous updating of complementary tools and methodologies following technological developments, (b) addressing the lack of detailed field observations, (c) increasing interactions of hydraulic specialists with other scientific disciplines and water experts, and (d) restoring a strong collaboration between academia and industry. It is anticipated that in this way the hydraulic structures community, and all of society, will make a new step toward more sustainable and resilient interactions with nature and between communities in water management. This article is categorized under: Engineering Water > Engineering Water