A Novel Control Strategy on Stable Operation of Fuel Gas Supply System and Re-Liquefaction System for LNG Carriers

Liquefied natural gas has attracted attention through an explosive increase in demands and environmental requirements. During this period, the Energy Efficiency Design Index (EEDI), which was adopted by the International Maritime Organization, expecting to significantly reduce CO2 from ships, has become an important key. It has triggered a change in use from steam turbine systems and dual fuel diesel electrics to high-efficiency main engines such as ME-GI engines to meet the EEDI requirements. However, since the ME-GI engines use 300 bar of fuel gas pressure, it is necessary to resolve problems of the pressure controllability and to prevent the reductions of the re-liquefaction amount caused by clogging of the lubricant mixed with the fuel gas during the compression. The purpose of this study is to propose a novel control strategy with a newly developed configuration for controlling the pressure so as not to trip the BOG compressors when the ME-GI engines are tripped, and for preventing a reduction on re-liquefaction amount. Unlike the typical configuration used in the current vessels, this proposal separately provides the fuel gas at 150 bar without lubricants to the re-liquefaction. In addition, three control strategies are proposed, depending upon the application of multi-controllers and the location of the pressure transmitters. A simulation was conducted to verify the efficacy of the proposed method, focusing on the controllability of the pressure and the re-liquefaction amount, in comparison with the typical configuration. As results of the simulation, the proposal showed excellent controllability without trips of the BOG compressors even in abnormal conditions and confirmed the great re-liquefaction performance.

Intelligent Calculation Method and Algorithm Optimization of Consumption Reducing for SCR and SNCR in Denitriation System

Since the environmental laws have been more and more strict about pollutants emissions of thermal power plant, SNCR and SCR system seems to be typical configuration. However the ammonia consumption calculation differs from different designers. In this paper the popular and experienced calculation method is introduced for thermal power plant dinitriation system.

Flow field of impinging sweeping jets

Sweeping jets are oscillating jets generated by fluidic oscillators, i.e., devices designed to produce an oscillation of the flow without the use of any moving parts (Raghu, 2013). A typical configuration of such devices consists of an expansion chamber connected to a high-pressure supply via a converging nozzle and provided with feedback channels. The oscillating motion in the expansion chamber is triggered by an inherent flow instability and sustained by the flow rate across the feedback channels. Recently, sweeping jets have been studied in flow control applications for noise reduction, separation and circulation control over airfoils, control of resonant cavity oscillations and deflection of jets. The advantageous features of fluidic actuators, among which are the wide range of operating frequencies (up to kHz with meso-scale) and the distributed momentum addition, have also stimulated an increasing interest in their application to electronics cooling. Several recent studies on the convective heat transfer from impinging sweeping jets (e.g., Hossain et al., 2018; Park et al., 2018) have shown that, compared to conventional round jets, they offer higher cooling rates with better uniformity at least for small jet-to-plate spacings.

Multi-tier mechanics control stromal adaptations in swelling lymph nodes

Lymph nodes (LNs) comprise two main structural elements: Fibroblastic reticular cells (FRCs) that form dedicated niches for immune cell interaction and capsular fibroblasts that build a shell around the organ. While LNs are fairly stable in size during homeostatic conditions, immunological challenge causes more than 10-fold increase in size within only a few days. How a solid organ can accommodate such extreme volumetric changes is poorly understood. Here, we characterize the biomechanics of LN swelling on the cellular and organ scale. We identify lymphocyte trapping by influx and proliferation as drivers of an outward pressure force, causing FRCs and their associated conduits to stretch. After an initial phase of relaxation, FRCs sense the resulting strain via cell matrix adhesions, which coordinates local growth and remodeling of the stromal network. While the expanded FRC network adopts its typical configuration, a massive fibrotic reaction of the organ capsule sets in and counters further organ expansion. Thus, different fibroblast populations mechanically control LN swelling in a multi-tier fashion.

DETERMINATION OF DEFORMATION PROPERTIES AND NATURAL STRESSES IN ROCK MASS BY UNDERGROUND GEODESY DATA

The authors have developed and implemented a 3D geomechanical model using the finite element method for a typical configuration of an underground space during room-and-pillar mining. The authors formulate and solve an inverse problem on determination of values and orientation of external horizontal stresses and deformation characteristics of structural elements of the geotechnology by the measurement data of sidewall convergence in rooms in the course of mining. The level curves of different objective functions are analyzed, the mixed inverse problem resolvability is demonstrated, and the equivalence domain size is correlated with the relative error of input data.

Setting the evolutionary timeline: Tillandsia landbeckii in the Chilean Atacama Desert

The Chilean Atacama Desert is among the oldest deserts of the world. Here, Tillandsia landbeckii is forming a unique vegetation type known as Tillandsia lomas. This vegetation consists in its typical configuration of one single vascular plant species only and forms regular linear structures in a sloped landscape and is largely depending on fog occurrence as dominant source of water supply. Without developing a typical root system, there are only few other terrestrial Tillandsia species growing on bare sand in Chile and Peru such as T. marconae, T. virescens, T. purpureaor T. latifolia. Although phylogenetic evidence is limited, convergent evolution of this unique growth behavior is evident. The predominantly arid and hyper-arid climate exists since the Early Miocene, which raises the question about timing of T. landbeckii evolutionary history. Phylogenomic analyses using whole plastome sequence data highlight the onset of diversification in T. landbeckii approximately 500,000 years ago. We also demonstrate subsequent secondary genetic contact with T. purpurea during the Late Pleistocene using DNA sequence data and genome size estimates, which resulted into the formation of T. marconae.

A Secure Methodology for Filtering Spam & Malware in E-mail System and Secure E-mail Testbed Setup

E-mail system is one of the critical infrastructures of any organization. It is necessary to ensure that the mail servers in use should be secured in such a way that no security properties like confidentiality, integrity, and authenticity are compromised. To achieve these security properties we have setup a secure e-mail server testbed that provides security against malware and spam, and guaranties secure e-mail delivery. This paper proposes a secure methodology for filtering spam and malware in the e-mail system, comprising standard layers of protocols and policies. An experimental testbed is established to evaluate the effectiveness of our methodology and was tested with spam and malware e-mails. Our results showed an accuracy of 95 percent, against a typical configuration of an e-mail system.

The Influence of Coding Tools on Immersive Video Coding

This paper summarizes the research on the influence of HEVC (High Efficiency Video Coding) configuration on immersive video coding. The research was focused on the newest MPEG standard for immersive video compression – MIV (MPEG Immersive Video). The MIV standard is used as a preprocessing step before the typical video compression thus is agnostic to the video codec. Uncommon characteristics of videos produced by MIV causes, that the typical configuration of the video encoder (optimized for compression of natural sequences) is not optimal for such content. The experimental results prove, that the performance of video compression for immersive video can be significantly increased when selected coding tools are being used.

Interaction from Structure using Machine Learning: in and out of Equilibrium

Prediction of pair potential given a typical configuration of an interacting classical system is a difficult inverse problem. There exists no exact result that can predict the potential given the...

Hands-Free User Interface for VR Headsets Based on In Situ Facial Gesture Sensing

The typical configuration of virtual reality (VR) devices consists of a head-mounted display (HMD) and handheld controllers. As such, these units have limited utility in tasks that require hand-free operation, such as in surgical operations or assembly works in cyberspace. We propose a user interface for a VR headset based on a wearer’s facial gestures for hands-free interaction, similar to a touch interface. By sensing and recognizing the expressions associated with the in situ intentional movements of a user’s facial muscles, we define a set of commands that combine predefined facial gestures with head movements. This is achieved by utilizing six pairs of infrared (IR) photocouplers positioned at the foam interface of an HMD. We demonstrate the usability and report on the user experience as well as the performance of the proposed command set using an experimental VR game without any additional controllers. We obtained more than 99% of recognition accuracy for each facial gesture throughout the three steps of experimental tests. The proposed input interface is a cost-effective and efficient solution that facilitates hands-free user operation of a VR headset using built-in infrared photocouplers positioned in the foam interface. The proposed system recognizes facial gestures and incorporates a hands-free user interface to HMD, which is similar to the touch-screen experience of a smartphone.