Recent Patents on Engineering - Volume 15, Issue 3, 2021

Background: Optimization of reinforced concrete foundation is a challenging problem due to the interaction between the design variables and design constraints. Classical design methods may overestimate the size of the foundation, thus leading to excessive cost. By using current advances in computer technologies and numerical optimization procedures, it is possible to find the optimum combinations of foundations design parameters that minimize the cost. Objectives: The paper presents a numerical strategy to optimize the design of the reinforced concrete foundation. Methods: The cost function is first derived in terms of the foundation design parameters. Mathematical programming technique is utilized to minimize the cost function. Design constraints are used against soil bearing capacity, concrete shear strength, flexural strength, and column bearing. Simplified analytical models are developed to idealize the soil stress distribution. The numerical procedure is then automated in a computer Program “OSFD” to perform sensitivity analysis and provide guidelines that can be utilized in practice. Results: Design examples are provided to illustrate the efficiency of the optimization procedure. Results are compared with existing common design procedures, commercial software and design handbooks that are available in practice. Conclusion: The described procedure is very cost-effective and can be utilized by practicing engineers in the industry to optimize the design of the reinforced concrete foundations.

Background: Capacitive Micromachined Ultrasonic Transducer (CMUT) is a new type of ultrasound transducer that has gained much research interest in ultrasound imaging because of its wider bandwidth, higher receiving sensitivity, and is more likely to be integrated with an integrated circuit (IC). The analytical solution is intuitive, fast, and convergent among simulation methods. The membrane deflection is important to the CMUT performance. The deformation of a circular CMUT under an external force can be described by von Kármán equations. Objective: To find suitable boundary conditions that are crucial for the governing equations to be properly solved to get the analytical solutions for membrane deformation. Methods: Features of two commonly used CMUT fabrication methods, Sacrificial Release method (SR) and Wafer Bonding (WB) method, are introduced. The force and moment equilibrium conditions of the supporting post are analyzed to get the boundary condition equations. Results: The analytical results match well with the Finite Element Method (FEM) results for the fixed boundary condition while there are still some differences for the elastic boundary condition. Conclusion: The boundary conditions for SR fabricated devices are elastic support while the boundary conditions for WB fabricated devices are fixed.

Contour crafting application has been widely used in different industrial, pharmaceutical, medical, and aviation applications for more than three decades. Recently, mega-sized 3-D printers were developed, with sufficient capability to print full-scale construction projects, including walls, homes, bridges, and multi-story buildings. Successful 3-D printing of projects is accomplished by the Additive Manufacturing (AM) process through the placement of successive layers of construction materials using robotic arms (3-D printers). This layered construction, known as contour crafting, is controlled by computer modeling software. This paper presents the history of contour crafting development, its current application in construction, the advantages of contour crafting applications in construction, and the main impediments to the widespread of contour crafting in the local construction market. In addition, this paper highlights the current research efforts made to integrate Building Information Modeling (BIM) in contour crafting construction. Based on the recent research findings, contour crafting application in construction improves job site productivity and project sustainability as a result of reduced material waste in construction sites. Finally, the automated construction through the application of contour crafting technique results in improved job site safety and increased overall quality of construction projects due to the increased automation in construction.

Background: Rolling mill vibration has become one of the most widespread and unsolved problems in the rolling industry, which is called "Ghost" vibration. The research on the starting mechanism, vibration characteristics and vibration suppression measures of high-speed tandem rolling mill has always been a hotspot and difficult point in the field of rolling at home and abroad. However, up to now, the research on rolling mill vibration has not formed a relatively complete and widely accepted theoretical system, experimental means and solutions. In production, vibration is often controlled by experience and test, which has a high cost and low efficiency. Methods: In this paper, the research history and achievements of vibration phenomena, vibration mechanism, the stability of the rolling process and vibration control theory of high-speed tandem rolling mill in recent years are summarized. The aim is to reveal the mechanism of rolling mill vibration in the continuous rolling process, the mechanism of rolling mill non-linear vibration instability and its changing law, and to explore the optimization of rolling process and the control method of rolling mill structure so as to improve the rolling process. Results: The evolution of non-linear random torsional / bending vibration and its transfer mechanism to the space coupling vibration of the roll system, the unsteady dynamic friction characteristics of the rolling interface and the mechanism of induced roll chatter, and the non-linear random dynamic behavior of the space coupling vibration of the roll system are revealed. Conclusion: The stability of the rolling process can realize the research and development of highend products considering the stability of the rolling process, and also provide a reference for further research by industry experts.

With the progression of technology, models of linear multistate consecutively-connected systems (LMCCSs) have been applied more widely, such as in telecommunication systems and the Internet of Things, among other applications. LMCCSs contain a series of linearly arranged nodes, and any disconnection between nodes will lead to the failure of the entire system. Thus, the reliability of a linear multistate system is affected by many factors, such as the positioning of elements. To be able to incorporate different types of complicated practical factors, researchers have proposed various extensions for the LMCCS model. Moreover, models have been proposed to study the optimal system configurations of such systems while considering reliability and some other objectives or constraints. Due to the amount of existing research on LMCCSs, this paper aims to review the related literature, classify these works, and elicit some future research directions.

Background: Nitrosamine is a chemical, commonly used as a preservative in red meat whose intake can cause serious carcinogenic effects on human health. The identification of such malignant chemicals in foodstuffs is an ordeal. Objective: The objective of the proposed research work presents a meta-heuristic approach for nitrosamine detection in red meat using a computer vision-based non-destructive method. Methods: This paper presents an analytical approach for assessing the quality of meat samples upon storage (24, 48, 72 and 96 hours). A novel machine learning-based method involving the strategic selection of discriminatory features of segmented images has been proposed. The significant features were determined by finding p-values using the Mann-Whitney U test at a 95% confidence interval, which were classified using partial least square-discriminant analysis (PLS-DA) algorithm. Subsequently, the predicted model was evaluated by the bootstrap technique, which projects an outline for preservative identification in meat samples. Results: The simulation results of the proposed meta-heuristic computer vision-based model demonstrate improved performance in comparison to the existing methods. Some of the prevailing machine learning-based methods were analyzed and compared from a survey of recent patents with the proposed technique in order to affirm new findings. The performance of the PLS-DA model was quantified by the receiver operating characteristics (ROC) curve at all classification thresholds. A maximum of 100% sensitivity and 71.21% specificity was obtained from the optimum threshold of 0.5964. The concept of bootstrapping was used for evaluating the predicted model. Nitrosamine content in the meat samples was predicted with a 0.8375 correlation coefficient and 0.109 bootstrap error. Conclusion: The proposed method comprehends the double-cross validation technique, which makes it more comprehensive in discriminating between the edibility of foodstuff, which can certainly reinstate conventional methods and ameliorate existing computer-vision methods.

Background: Greenhouse cooling is very essential during warm conditions to extend the cropping season and offer year-round production. Although fan-pad systems are widely utilized for greenhouse cooling in arid climates, they have many drawbacks mentioned by researchers. Thus, finding the best cooling system had attracted the attention of many researchers and inventors in such climates. Objective: This paper aims to review the recent patents of greenhouse cooling methods suitable for arid climates. Methods: The most relating patents on greenhouse cooling technologies were discussed and analyzed. Results: A total of 46 patents were reviewed, covering over 21 years, and the majority of them (73.9%) were patented in China, followed by the USA (15.2%), worldwide (4.3%), Japan (2.2%), Russia (2.2%) and Austria (2.2%). The patents were divided into three categories; preventive (8 patents), corrective (33 patents) and combined (5 patents) greenhouse cooling techniques. In the preventive techniques, i.e. avoiding heat load in greenhouses, patents involving shading mechanisms were dominant because it is well known that shading reduces solar radiation penetration as the largest heating source in greenhouses. In the corrective techniques, i.e. removing the accumulated heat, patents on evaporative cooling mechanisms were dominant but their suitability for arid climates is hindered with high humidity and water scarcity. In the combined techniques, i.e. including both preventive and corrective techniques, patents are very comprehensive and thus implementable in hightech commercial greenhouses. Some innovative patents involving refrigerative cooling, desiccation, solar power and multi-systems were also highlighted. Conclusion: Patents implementing preventive cooling techniques alone are insufficient in arid climates due to the extremely high ambient temperatures in the hot months. Similarly, patents involving evaporative cooling methods are constrained by high humidity and water scarcity in arid conditions. Therefore, patents combining preventive and corrective techniques are more energy- and water- efficient. We recommend future work to focus on desiccant-indirect evaporative cooling methods as they can overcome the high humidity limitations in many arid areas.

Embedded multi-core systems often show special limitations in sharing resources and storage capacity, which will lead to the reduction of parallel efficiency due to bandwidth, data competition and other factors. In this paper, a run-time optimization framework is proposed to dynamically and adaptively adjust parallel strategies according to the structure of different parallel programs. On the one hand, the performance analysis model of a parallel program structure is established to get the number of threads during the best performance. On the other hand, in view of the load imbalance in parallel thread execution, an adaptive dynamic scheduling algorithm is proposed to dynamically select the size of the scheduling block. Experimental results show that the proposed dynamic scheduling strategy can improve program performance and achieve improvement of the performance of the embedded multi-core system. Background: Embedded multi-core systems often have special limitations in sharing resources and storage capacity. These limitations often lead to parallel programs running with lower parallel efficiency due to bandwidth, data competition and other factors. Objective: In order to improve the performance of embedded multi-core systems, parallel strategies can be adjusted dynamically and adaptively for different parallel program structures. Methods: A control mechanism of the thread count based on runtime information feedback is proposed, which enables the system to dynamically select the number of threads when the program runs best according to the structure characteristics of parallel programs. Then, an adaptive dynamic scheduling algorithm is proposed to solve the load imbalance in parallel program execution. Results: An optimization framework based on run-time architecture is presented, which consists of two parts: performance monitoring and control interface. It can take corresponding optimization strategies according to the running state of parallel programs. Conclusion: The performance of the embedded multi-core system is improved.

Background: At present, there are a few research studies on the stability of the supporting structure of bored piles with steel supports for deep foundation pits, and it is even less common to use this support method for deep foundation pits in sandy pebble stratum. This paper studied the stability of the deep foundation pit support of the Southwest Jiaotong University Station in Chengdu, China, using the stability analysis theory of bored piles with steel supports for deep foundation pits. Objective: The study aims to show the stability of steel supports for deep foundation pits. Methods: The overall stability, anti-overturning stability and uplift stability of the foundation pit are important components of the stability analysis of bored piles with steel supports for deep foundation pits. Aiming at the designed method and parameters of the bored piles with steel support for the deep foundation pit, in-depth theoretical analysis, and calculation of the overall stability, antioverturning stability, and uplift stability of the deep foundation pit are conducted, respectively. Results: The results show that the stability of the deep foundation pit using bored piles with steel support meets the requirements, indicating that the design of this support form is safe and reasonable, thus ensuring the smooth progress of the project. Conclusion: The stability analysis of deep foundation pits in sandy pebble stratum provides ideas for the optimization of deep foundation pits and a reference for the stability analysis of deep foundation pits in sandy pebble stratum and other types of the stratum.

Aims and Objectives: Mobile Ad hoc Networks (MANET) hold a set of numerous mobile computing devices useful for communication with one another with no centralized control. Due to the inherent features of MANET such as dynamic topology, constrained on bandwidth, energy and computing resources, there is a need to design the routing protocols efficiently. Flooding is a directive for managing traffic since it makes use of only chosen nodes for transmitting data from one node to another. This paper intends to develop a new Cluster-Based Flooding using the Fuzzy Logic Scheme (CBF²S). Methods: To construct clusters and choose proper cluster heads (CHs), the fuzzy logic approach is applied with the use of three parameters namely link quality, node mobility, and node degree. The presented model considerably minimizes the number of retransmissions in the network. Results: The presented model instructs the cluster members (CM) to flood the packets inside a cluster which is known as intra-cluster flooding and CHs to flood the packets among the clusters which is known as inter-cluster flooding. In addition, the gateway sends a packet to another gateway for minimizing unwanted data retransmissions when it comes under different CH. The presented CBF²S is simulated using the NS2 tool under the presence of varying hop count. Conclusion: The CBF²S model exhibits maximum results over the other methods in terms of overhead, communication overhead, traffic load, packet delivery ratio, and the end to end delay.

Background: Most non-developing and under developing countries strive hard to tackle the situation of power crisis and to combat the imbalance between the power generation and load demand, especially in the case of increasing of the population. In this situation, the load shedding scheme has been extremely implemented as a fast solution for unbalance conditions. Thus, load shedding is crucial to investigate supply-demand balancing in order to protect the network from collapsing and to sustain stability as possible; however its implementation is mostly undesirable. Objective: prioritize the loads according to their importance and apply reduction strategy in the demands while the supplied power to the important loads such as health care and security installation are kept intact without any interruption as possible. Methods: The conventional methods of load shedding lead to over or under shedding and this may lead to many problems with the network. Under the scheme, these methods disconnect the load or the entire feeder without considering their priorities and may not perform as anticipated. In this work, we propose a logarithmic reduction method to reduce the load according to the priority and day life criticality. The method for shedding the load base on Reduction Matrix and which in turn depend on the priority demands. Results: The higher priority demands are fed with a reliable power source by the real time monitoring of the network accompanied with power reducing for the lower priority demands. Conclusion: We test a real data sample provided by the Iraqi national grid control center in Baghdad. Our simulation results prove effectiveness and practicality of the applied method paving the way for possible applications in power systems.

Background: The perineum area that interacts with the saddle is vulnerable; compressing neurovascular tissues has been asserted as the link to pathologies. Existing saddle designs are mainly based on the hole blocks, which are composed of two materials. These composite combined structures increase manufacturing difficulty. Objective: The injection molding technology is suitable for mass production. We proposed a saddle design to meet the ergonomic requirements of cyclists. Saddle frames present a continuous curvature geometry to ensure improved injection modeling. Methods: Static numerical calculations and measurements were employed for vertical load evaluations with different stiffness regions acquired using perforated chain patterns. Two-step plastic injection molding was utilized with proper bonding and processing compatibility. In prototyping, the first and second shots are PC and TPE, respectively. Results: The frame sustains vertical loadings from bending and provides adequate stiffness and proper flexibility. The computer-aided design mold increases the contact area, and annular grooves increase the adhesion between two materials. The outer frame exhibits high rigidity; the middle area exhibits flexibility and high deformation. Conclusion: This question is widely noticed and various answers have been proposed. By investigating the patent database and searching journal papers on saddle designs, the authors confirmed the novelty of the proposed structure.