Design and Prototype Test of key components of Segmented Ligusticum wallichii Harvester

According to the harvest demand of Ligusticum wallichii, a segmented Ligusticum wallichii harvester was designed. The crushing device was set in the front end of tractor and the vibrating harvester was mounted in the rear end of tractor. Firstly, the strength test of Ligusticum wallichii stalks was carried out, and the basic parameters of the crushing device were determined. The results showed that the minimum required speed of the crushing device was 3880r/min. Secondly, the vibration structure was modeled and analyzed by vector equation, and the vibration structure was simulated and analyzed by ADAMS, and the parameters of the vibration structure were determined. The results showed that when the crank angle was 22~100°, the Ligusticum wallichii-soil mixture was thrown backward away from the vibration steel bar, and throw away distance was 88.42mm. Finally, the field prototype test was carried out. During the test, the crushing device could crush the stems of Ligusticum wallichii normally. The rotational speed was measured at 4020r/min. The obvious rate, loss rate and damage rate of Ligusticum wallichii stem were calculated. The stems obvious rate was 95%, loss rate was 4.5% and damage rate was 0.4%, which met the harvest requirements of Ligusticum wallichii.

Design Thinking as a Method for Developing Caregiver (and Other) Interventions

“Design Thinking,” an innovative, human-centric approach to problem-solving, seeks to ensure that design efforts “solve the right problem.” This presentation describes the Design Thinking process and illustrates its use in the context of three design studio sessions with of family caregivers of patients at the Integrated Memory Care Clinic (IMCC), a comprehensive medical home for persons living with dementia. The Design Thinking process entails five steps – Empathize, Define, Ideate, Prototype, Test – that engage consumers/end-users to identify, as precisely as possible, the issues or concerns that are most important to them and to further identify the possible solutions that seem to most fully address these concerns. The process can be described as one of divergent and convergent thinking. In the first session, the Empathize phase, IMCC caregivers were asked to think as broadly as possible about needs not being met by IMCC. These topics were reviewed more convergently in the second session, the Define phase; here the participants agreed on a shorter, prioritized list of needs to be addressed. In the third session (that combined the Ideate and pre-Prototype stages), participants identified 14 topics (interventions) they felt should be included in this program. Finally, in the Test phase, they assessed the topics and agreed that the most important need IMCC could address would be to provide a comprehensive orientation program for new caregivers. IMCC clinicians concurred with the salience of the problem to be solved and saw addressing it as contributing substantially to the improvement of IMCC clinical care.

Experimental investigation of bubble formation and motion mechanism near the moonpool

When a research ship sails at a high speed, there is relative motion between the ship and fluid. The ship is slammed by the fluid. To reduce the direct impact of the fluid, sonar is installed in the moonpool, and acoustic detection equipment is installed along the research ship bottom behind the moonpool. However, during high-speed sailing, a large number of bubbles form in the moonpool. Some bubbles escape from the moonpool and flow backward along the bottom of the ship. When a large number of bubbles are around the sonar and acoustic detection equipment, the equipment malfunctions. However, there have been few studies on bubble formation in the moonpool with sonar and distribution along the ship bottom behind the moonpool. Therefore, a related model was developed and prototype tests were carried out in this study. The appropriate similarity criteria were selected and verified to ensure the reliability of the experiment. Considering the influences of speed, sonar, moonpool shape, and draft, the reason and mechanism of bubble formation in a sonar moonpool were studied. An artificial ventilation method was used to simulate a real navigation environment. Because the bubbles are in a bright state under laser irradiation, the bubbles can be used as tracer particles. A high-speed camera captured illuminated bubbles. The distribution mechanism of bubbles along the ship bottom behind the moonpool was investigated using particle image velocimetry under the influence of the moonpool shape and sailing speed. The model experimental results agreed well with those of the prototype test. The air sucked into the water was the dominant factor in bubble formation in the moonpool. The bubbles were distributed in a W shape under the ship bottom.

Prototype Test and Numerical Analysis of a Shallow Cable with Novel Viscous Inertial Damper

As an essential component of offshore bridges, stay cables are prone to vibrations due to their low inherent damping characteristics. Various dampers have been used for cable vibration control; however, the experimental research and theoretical study of inertial dampers on real cables have not been conducted sufficiently. This study aims to investigate the damping performance of a novel viscous inertial damper (VID) and focuses on the frequency-dependent and displacement amplification phenomena of a cable-damper system. Tests were first conducted to verify the energy consumption capacity of a prototype damper. A shallow cable-VID system was established. Theoretically, complex-valued modes were analyzed to determine the influence of the inertial and viscous coefficients on the cable’s frequency and mode damping ratio. The test results and numerical analysis show that the VID has a good damping effect on the shallow cable. Considering multiple adjacent cable modes, the inertial and viscous coefficients can be optimized. After optimizing, the VID can simultaneously maximize both adjacent symmetric and antisymmetric modes’ damping ratios. The two frequencies are almost the same. The displacement amplification of the VID shows that a VID can overcome the shortcomings of displacement loss caused by traditional oil dampers. The implications of these findings of the VID on shallow cable are discussed, which will guide future research and applications of the VID or other inerter dampers.

Similarity Law between Centrifuge Scale Test and Prototype Underwater Explosion

Shock wave and bubble pulsation caused by underwater explosion destroy the hydraulic structure. However, the realization of the underwater explosion prototype test is restricted by many factors, such as the site environment. Furthermore, the repeatability of the test scheme is not strong. The centrifuge scale test provides a new way of studying the damage degree of the structure under the action of underwater explosion. The similarity relationship refers to the bridge between the scaled model and the prototype, which cannot achieve complete similarity in practice. The centrifuge-scaled model test is performed by increasing the acceleration of a certain multiple. Meanwhile, the model reduces the corresponding ratio in the geometric layout to achieve the geometric similarity with the prototype test. Therefore, the applicability of the centrifuge scaling method in the study of the dynamic response of the structure in underwater explosion needs to be explored further. In this work, the underwater explosion scaling test numerical model for 1 g RDX (equivalent to 1.62 g TNT) charge under different centrifugal acceleration conditions is established, and the calculation results of underwater pressure and dynamic response of the steel plate are compared with the centrifuge test results. A prototype model is established to study the similarity relationship between the centrifuge scale test and the prototype model when the steel plate structure is in the stage of small deformation and linear elasticity. The application of the similarity ratio in the scale test of underwater explosion the centrifuge is discussed. The application of the centrifuge in the study of the failure response of the hydraulic structure in underwater explosion is expanded by establishing the model and comparing with the experimental results.

Fluctuations and phases in baryonic matter

The phase structure of baryonic matter is investigated with focus on the role of fluctuations beyond the mean-field approximation. The prototype test case studied is the chiral nucleon-meson model, with added comments on the chiral quark-meson model. Applications to nuclear matter include the liquid-gas phase transition. Extensions to high baryon densities are performed for both nuclear and neutron matter. The role of vacuum fluctuations is systematically explored. It is pointed out that such fluctuations tend to stabilize the hadronic phase characterized by spontaneously broken chiral symmetry, shifting the chiral restoration transition to very high densities. This stabilization effect is shown to be further enhanced by additional dynamical fluctuations treated with functional renormalisation group methods.

Experimental Analysis of Bending Stiffness Characteristics of Grouted Double Mortise-Tenon Joint for Prefabricated Metro Station Structure

The grouted mortise-tenon joint, invented as the connection between the large prefabricated components, is the key to the prefabricated underground structures, and the double-tenon joint is most widely used in the prefabricated metro station structure. This paper conducts characteristic analysis of bending stiffness with a 1 : 1 prototype test in key working direction of different joint types for grouted double mortise-tenon joint. The results show that the double-tenon joint is characteristic of variable stiffness under different loads. Change laws of double-tenon joint bending stiffness without and with auxiliary pretightening device in tension side and compression side are also discussed. The correlations for calculating double-tenon joint bending stiffness with various axial loads and bending moments are derived at last, which offers the theory foreshadowing of similar joints.

Conversational Code Analysis: The Future of Secure Coding

The area of software development and secure coding can benefit significantly from advancements in virtual assistants. Research has shown that many coders neglect security in favor of meeting deadlines. This shortcoming leaves systems vulnerable to attackers. While a plethora of tools are available for programmers to scan their code for vulnerabilities, finding the right tool can be challenging. It is therefore imperative to adopt measures to get programmers to utilize code analysis tools that will help them produce more secure code. This chapter looks at the limitations of existing approaches to secure coding and proposes a methodology that allows programmers to scan and fix vulnerabilities in program code by communicating with virtual assistants on their smart devices. With the ubiquitous move towards virtual assistants, it is important to design systems that are more reliant on voice than on standard point-and-click and keyboard-driven approaches. Consequently, we propose MyCodeAnalyzer, a Google Assistant app and code analysis framework, which was designed to interactively scan program code for vulnerabilities and flaws using voice commands during development. We describe the proposed methodology, implement a prototype, test it on a vulnerable project and present our results.