Component technologies for e-discovery and prototyping of suit-coping system

As ESI (Electronically Stored Information) is included in extent of evidence that become discovery\u27s target in FRCP(Federal Rules of Civil Procedure) taken effect on December 1, 2006, enterprises been always vexing in several litigations need to adapt systems coping with e-Discovery such as ESI administration or information preservation. In this paper, component technologies for all steps of e-Discovery are described in detail, and as a prototype of preparing system for e-Discovery, agent-based information management and control system being able to manage ESI stored at some computers centrally and respond rapidly on demand, extracting discoveryrelated data using digital forensic technologies, are introduced. Apart from fundamental searching and analysing functions, this system can detect user’s abnormal behaviours, generate forensic images remotely, and have a function of controlling related files

Near-Field Analysis and Design of Inductively-Coupled Wireless Power Transfer System in FEKO

Inductively-coupled wireless power transfer (WPT) system is broadly adopted for charging batteries of mobile devices and electric vehicles. The performance of the WPT system is sensitively dependent on the strength of electromagnetic coupling between the coils, compensating topologies, loads and airgap variation. This paper aims to present a comprehensive characteristic analysis for the design of the WPT system with a numerical simulation tool. The electromagnetic field solver FEKO is mainly used for studying high-frequency devices. However, the computational tool is also applicable for not only the analysis of the electromagnetic characteristic but also the identification of the electrical parameters in the WPT system operating in the nearfield. In this paper, the self and mutual inductance of the wireless transfer windings over the various airgaps were inferred from the simulated S-parameter. Then, the formation of the magnetic coupling and the distribution of the magnetic fields between the coils in the seriesparallel model were examined through the near-field analysis for recognizing the efficient performance of the WPT system. Lastly, it was clarified that the FEKO simulation results showed good agreement with the practical measurements. When the input voltage of 10 V was supplied into the transmitting unit of the prototype, the power of 5.31 W is delivered with the transferring efficiency of 97.79% in FEKO. The actual measurements indicated 95.68% transferring efficiency. The electrical parameters; in , out, in , , in , and out, had a fair agreement with the FEKO results, and they are under 8.4% of error

Study of the ecological gas for MRPCs

The Multigap Resistive Plate Chamber (MRPC) is a gaseous detector; the performance depends very much on the gas mixture as well as the design. MRPCs are used as a timing device in several collider experiments and cosmic ray experiments thanks to the excellent timing performance. The typical gas mixtures of RPC-type detectors at current experiments are based on the gases $\rm C_2F_4H_2$ and $\rm SF_6$. These gases have very high Global Warming Potential (GWP) values of 1430 and 23900 respectively. The present contribution has been performed as a part of efforts to reduce the amount of greenhouse gases used in high energy experiments. The performance of MRPC has been measured with two different gas mixtures; $\rm C_2F_4H_2$ based gas mixtures and the ecological $\rm C_3F_4H_2$ (HFO-1234ze). A small MRPC was used for the tests. It has an sensitive area of 20 $\times$ 20 $\rm cm^2$; it was been built with 6 gaps of 220 $\mu$m. In normal operation, the strong space charge created within the gas avalanche limits the avalanche's growth. $\rm SF_6$ plays an important part in the process due to its high attachment coefficient at low electric fields. It is thus necessary to find another gas that has a similar attachment coefficient. $\rm CF_{3}I$ is a possible candidate. Tests were performed with this gas added to $\rm C_3F_4H_2$

Crack-Growth Behavior in Thermal Barrier Coatings with Cyclic Thermal Exposure

Crack-growth behavior in yttria-stabilized zirconia-based thermal barrier coatings (TBCs) is investigated through a cyclic thermal fatigue (CTF) test to understand TBCs’ failure mechanisms. Initial cracks were introduced on the coatings’ top surface and cross section using the micro-indentation technique. The results show that crack length in the surface-cracked TBCs grew parabolically with the number of cycles in the CTF test. Failure in the surface-cracked TBC was dependent on the initial crack length formed with different loading levels, suggesting the existence of a threshold surface crack length. For the cross section, the horizontal crack length increased in a similar manner as observed in the surface. By contrast, in the vertical direction, the crack did not grow very much with CTF testing. An analytical model is proposed to explain the experimentally-observed crack-growth behavior

Crack-Resistance Behavior of an Encapsulated, Healing Agent Embedded Buffer Layer on Self-Healing Thermal Barrier Coatings

In this work, a novel thermal barrier coating (TBC) system is proposed that embeds silicon particles in coating as a crack-healing agent. The healing agent is encapsulated to avoid unintended reactions and premature oxidation. Thermal durability of the developed TBCs is evaluated through cyclic thermal fatigue and jet engine thermal shock tests. Moreover, artificial cracks are introduced into the buffer layer’s cross section using a microhardness indentation method. Then, the indented TBC specimens are subject to heat treatment to investigate their crack-resisting behavior in detail. The TBC specimens with the embedded healing agents exhibit a relatively better thermal fatigue resistance than the conventional TBCs. The encapsulated healing agent protects rapid large crack openings under thermal shock conditions. Different crack-resisting behaviors and mechanisms are proposed depending on the embedding healing agents

A Two-Dimensional Electronically-Steerable Array Antenna for Target Detection on Ground

Target-detection with a proof-of-concept electronically-steerable array (ESA) antenna is demonstrated in this paper. First, the clutter level is investigated by using vertically-and horizontally-polarized electric fields. Two metallic cylinders with different sizes are subsequently used as targets and are characterized using standard 15-dBi horn antennas. The bigger cylinder reflects about 3 dB higher power than the smaller one. A 2x2 ESA antenna is designed, fabricated and tested for two-dimensional beam steering. Unlike standard horn antennas that exhibit no electronic steering, the 2x2 ESA is able to identify a target location by steering the beam angle from -40 to +40 degrees, when the target is placed at -25, 0, and +25 degrees. The reflected power from each target is 5 dB less when illuminated by the proof-of-concept 2x2 ESA than when illuminated by the standard horn antenna. This is due to the 5.2 dB gain difference between the two antennas. The findings of this work show the potential of ESAs in target detection technology

Third-order exceptional point in an ion-cavity system

We investigate a scheme for observing the third-order exceptional point (EP3) in an ion-cavity setting. In the lambda-type level configuration, the ion is driven by a pump field, and the resonator is probed with another weak laser field. We exploit the highly asymmetric branching ratio of an ion's excited state to satisfy the weak-excitation limit, which allows us to construct the non-Hermitian Hamiltonian $(H_{\textrm{nH}})$. Via fitting the cavity-transmission spectrum, the eigenvalues of $H_{\textrm{nH}}$ are obtained. The EP3 appears at a point where the Rabi frequency of the pump laser and the atom-cavity coupling constant balance the loss rates of the system. Feasible experimental parameters are provided.Comment: 9 pages, 6 figure

Dealing with multiple hazards and threats on cultural heritage sites: An assessment of 80 case studies

Purpose: Cultural heritage (CH) sites are not only important components of a country’s identity but can also be important drivers of tourism. However, an increasing number of extreme events associated with the impacts of climate change, natural hazards and human-induced threats are posing significant problems in conserving and managing cultural heritage worldwide. Consequently, improved climate change adaptation and enhanced hazard/threat mitigation strategies have become critical (but to-date under researched) considerations. This paper aims to identify the key hazards and threats to cultural heritage sites, the most common types of risks to CH and the strategies being adopted to mitigate or even eradicate those risks. Design/methodology: This paper reviews 80 CH case studies from around the world, which have been presented at a UNESCO International Training Course between 2006-2016. The case studies cover 45 different countries and provide practical insights into the key challenges being encountered in a variety of ‘at risk’ locations. Findings: The analysis assesses the key natural hazards and human-induced threats to the sites, an overview of the typical impacts to the tangible components of heritage and identifies the types of strategies being adopted to mitigate the risks, some of which could be transferred across cultural and geographical contexts. Originality: The paper provides a wealth of useful information related to how challenges faced by CH sites might be addressed in the futur

Trait-based evaluation of plant assemblages in traditional farm ponds in Korea: Ecological and management implications

The Korean traditional farm pond called dumbeong is an important rural landscape element that supports local biodiversity and is useful in irrigating agricultural fields during dry periods. This study assesses how plant communities in dumbeongs respond to adjacent land use, water depth, open-water surface, and nutrient levels and irrigation usage. Plant functional and species groups, based on trait and species data respectively from 20 dumbeongs in Seocheon-gun, South Korea, were classified by hierarchical analysis and non-metric multidimensional scaling. Relationships between the plant community composition and explanatory variables at both the species and functional group levels were tested through redundancy analysis. The results showed that irrigation usage prevented nutrient accumulation and water depth reduction of the ponds, and we found water depth was the only significant factor that determined plant composition at both species and functional group levels. The plant functional groups were more useful than plant species in predicting plant composition in dumbeongs, owing to their collective response to water depth and open-water surface. Our results demonstrate that management practices of dumbeong, such as periodic drainage, sediment removal and control of dominant plant species, alter its plant communities and thus need to be considered for biodiversity conservation in agricultural landscapes.