Forensic on Construction Induced Failure of Pipe Pile Foundations

This paper introduces a case where pipe piles failed during construction. The accident happened when constructing the Jiaoxi Pumping Station project in the southern China. The site consists of very soft sludge and silt deposits. Pipe piles were used as foundation under the station structure. The installed pipe piles were observed to show significant inclination during the construction. A forensic investigation was performed. The driving forces for pipe pile failure were attributed to the lateral load induced by the excavation activities. Small strain integrity test and inclination measurement were taken to determine the location of breakage and the extent of inclination. The test results combined with theoretical analysis were able to determine the cause of pipe pile failure. Remediation measures were designed and implemented based on the results of forensic analyses. Recommendations were proposed to guide construction activities on soft soil deposit. The results of implementing these guidelines during remediation construction were satisfactory

Sludge Digestion By Anaerobic Fluidized Beds. I: Lab Performance Data

This study was undertaken to evaluate the laboratory performance of the anaerobic fluidized bed digesting secondary biological sludge at 35° C with four hydraulic-retention times (HRTs): 1, 2.5, 5, and 10 days. In addition, the effects of both operating temperature (15° C, 25° C and 35° C) and the initial sludge solubilization on the digester performance were also examined. It was found that at 35° C, an adequate degree of sludge digestion was obtainable with an HRT of only 1-2 days if the influent biological sludge was presolubilized by treatment with 17.5 meq/L of sodium hydroxide. If no presolubilization was used, the necessary HRT was increased to 10 days. When the temperature was decreased to 25° C and the sludge was presolubilized, the required HRT was 2.5-3 days. However, as the temperature was further decreased to 15° C, the system was unable to achieve adequate digestion in as long as 10 days, even with presolubilization. It was also observed that the fluidized-bed system was able to accept abrupt increases of loading without a corresponding buildup of excessive organic acids. © ASCE

A Unified Framework for Mutual Improvement of SLAM and Semantic Segmentation

This paper presents a novel framework for simultaneously implementing localization and segmentation, which are two of the most important vision-based tasks for robotics. While the goals and techniques used for them were considered to be different previously, we show that by making use of the intermediate results of the two modules, their performance can be enhanced at the same time. Our framework is able to handle both the instantaneous motion and long-term changes of instances in localization with the help of the segmentation result, which also benefits from the refined 3D pose information. We conduct experiments on various datasets, and prove that our framework works effectively on improving the precision and robustness of the two tasks and outperforms existing localization and segmentation algorithms.Comment: 7 pages, 5 figures.This work has been accepted by ICRA 2019. The demo video can be found at https://youtu.be/Bkt53dAehj

Improving Timeliness in the Neglected Tropical Diseases Preventive Chemotherapy Donation Supply Chain through Information Sharing: A Retrospective Empirical Analysis

BACKGROUND: Billions of doses of medicines are donated for mass drug administrations in support of the World Health Organization’s “Roadmap to Implementation,” which aims to control, eliminate, and eradicate Neglected Tropical Diseases (NTDs). The supply chain to deliver these medicines is complex, with fragmented data systems and limited visibility on performance. This study empirically evaluates the impact of an online supply chain performance measurement system, “NTDeliver,” providing understanding of the value of information sharing towards the success of global health programs. METHODS: Retrospective secondary data were extracted from NTDeliver, which included 1,484 shipments for four critical medicines ordered by over 100 countries between February 28, 2006 and December 31, 2018. We applied statistical regression models to analyze the impact on key performance metrics, comparing data before and after the system was implemented. FINDINGS: The results suggest information sharing has a positive association with improvement for two key performance indicators: purchase order timeliness (β = 0.941, p = 0.003) and—most importantly—delivery timeliness (β = 0.828, p = 0.027). There is a positive association with improvement for three variables when the data are publicly shared: shipment timeliness (β = 2.57, p = 0.001), arrival timeliness (β = 2.88, p = 0.003), and delivery timeliness (β = 2.82, p = 0.011). CONCLUSIONS: Our findings suggest that information sharing between the NTD program partners via the NTDeliver system has a positive association with supply chain performance improvements, especially when data are shared publicly. Given the large volume of medicine and the significant number of people requiring these medicines, information sharing has the potential to provide improvements to global health programs affecting the health of tens to hundreds of millions of people

Sludge Digestion By Anaerobic Fluidized Beds. II: Kinetic Model

A model has been developed to describe the gas production and soluble-COD variations from the digestion of waste-activated sludge in the anaerobic fluidized-bed reactor. It indicates that a substantial rate increase can be attained by prehydrolysis of the biological sludge, external to the reactor. The model indicates that the rate-limiting step is in the sludge hydrolysis. The model is developed from an assumption of first-order kinetics in a set of series and parallel, irreversible reactions. That is, the formation of soluble substrate is first order with respect to the particulate biomass present, and that the production of methane is first order with respect to the soluble substrate present. The amount of particulate biomass can be approximated by the sludge-suspended solids and that the amount of soluble substrate can be approximated by the soluble COD present in the reactor. The model correlates well with the laboratory data observed in the study. © ASCE

The design and implementation of PowerMill

In this paper we discuss the design and implemen-tation of the simulator PowerMill, a novel transistor level simulator for the simulation of current and power behavior in vlsi circuits. With a new transistor mod-eling technology and a versatile event driven simu-lation algorithm, PowerMill is capable of simulating detailed current behavior in modern deep-submicron cmos circuits, including sophisticated circuitries such as exclusive-or gates and sense-ampliers, with speed and capacity approaching conventional gate level sim-ulators. The high accuracy and speed have made it possible for designers to study and verify detailed cur-rent behavior of large functional blocks or even an en-tire chip with a reasonable amount of CPU resources, making it a de facto industry standard for power sim-ulation.