Swing Type Research Articles

Hydrodynamic responses of a large flexible net swinging in waves

In deep-sea aquaculture cages, large flexible nets are usually mounted on the steel frames of aquaculture cages, which are easily broken. When a cage vibrates over time, the flexible nets also oscillate, causing relative motions with respect to fluid flows. This study focuses on the hydrodynamic behaviors of a large flexible net swinging in waves, in which three different types of swings are simulated with the swing center located above, on, and below the net, respectively. The incoming waves are simulated using the Airy wave theory. The nonlinear vibrations of the flexible net in three dimensions are solved using the lumped-mass method. The influences of swing amplitudes and frequencies on the vibrations of the net are analyzed in detail. It can be known that with the increase of swing amplitude, the vibration displacements of the net in the horizontal direction decrease, while they increase in the vertical direction. Furthermore, the dynamic tensions of net twines increase as the swing angular frequency rises.

Design and Analysis of Double Stator Swing Rotating Permanent Magnet Spherical Motor

This article presents a new type of double stator swing rotating permanent magnet spherical motor (DSSRPMSM), which can realize swing, rotation, and helical motion and is used in industrial robots, gyroscopes, satellite communications, and other fields. The proposed spherical motor consists of two stators and a hollow rotor with permanent magnet (PM) poles on its inner and outer surfaces. Compared with most spherical motor with hollow coil and traditional PM synchronous motor, the structure of the motor is different and novel, and it is difficult to find a more perfect design theory and method. Thus, this article introduces the new idea of motor design in detail. First, the structure and working principle of the motor are introduced, and the original design of the motor is carried out. The 2-D rough estimation and 3-D FEM accurate simulation calculation are carried out, and the electromagnetic characteristics of the motor are obtained, including magnetic flux density distribution, torque, and loss. The simulation results meet the design specifications of the motor. A prototype was built and tested. The experimental results are in good agreement with the 3-D FEM analysis. The design method provides a theoretical basis for the design of this kind of spherical motor. The research results lay a foundation for the subsequent optimization of the motor.

Energy Efficient Utilization toward Rural Biomass Waste by Straw Biogas Engineering

In this article, we summarize and analyze the constraints and technical difficulties of biogas plants in clusters, storage and transportation yards, pretreatment yards, and anaerobic fields. Combined with Tyre’s own experience, several major techniques have been proposed. To guide and recommend the suitable technicians to decision makers, to acquire operation courses suitable for the general requirements of our biogas, and to promote the development of booth biogas seedlings in China, the use of environmental slam objects in a small and sufficient nonscale biogas program is formulated by the use of biogas funding alone. Current rating measures leverage the World Age Assessment (LCA) for the Integrated Booth Biogas Swing Type (typically 40,000 kWh) and Bio-Natural Gasoline Program (daily gasoline workload of 12,000 cubic curves). This is built upon the Environmental Impact Assessment and Analogy for Warships Both environmental stroke and sensitivity component analysis. These techniques include termination outlines, register analysis, dynamism drops for each performance stagecoach, and environmental issue calculations. According to the above summarization, when biogas dominates the family, the highest environmental emission becomes the biogas fermentation layer of the booth. Meanwhile, the most sympathetic substitute is the work cost of physical and chemical farting (mL g-1TS). The above two indicators denote the essence of biogas purification, and the choice of biogas purification technology. By evaluating the change in the impact of suppressing environmental emissions, the biogas substitute of scorpion charcoal has a remarkable improvement in the biogas equivalent of the charcoal-bright swing family. Comprehensive experimental results have demonstrated this conclusion.

Distance Protection of Transmission Lines in Presence of Inverter-Based Resources: A New Earth Fault Detection Scheme During Asymmetrical Power Swings

Although it is commonly assumed that power swing is symmetrical and will have identical effects on all three-phase voltages and currents, there is another type of power swing, which is asymmetrical and mainly occurs during single-pole tripping (SPT), the impact of which on power systems integrated with the inverter-based resources (IBRs) has not been investigated so far. Since the likelihood of the occurrence of asymmetrical power swing is increasing in today's heavily loaded transmission lines, this article investigates the impact of IBR integration on the performance of distance protection during single-pole tripping. Furthermore, a new scheme is proposed to detect earth faults that occur during asymmetrical power swings to enhance the performance of power swing blocking functions. To do so, the superimposed component of the zero-sequence current during SPT is extracted. Then, the moving average window is used to calculate the average of both zero-sequence current and its superimposed component. Furthermore, to enhance the security of the proposed scheme, a new technique based on the phase angle shift between the three-phase currents is devised to detect the asymmetrical power swing conditions. This article shows that as the penetration level of IBRs increases, the standard reclosing dead-time needs to be revisited otherwise it can create an unstable power swing condition, even during SPT. Moreover, this article shows that the proposed earth fault detection scheme can efficiently detect all single-line-to-ground faults occurring during SPT.

다기능 조파기의 조파 운동과 발생 파형

Piston type wave makers or flap type wave makers are usually adopted as a wave maker which disturbing the fluid domain with sinusoidal motion. Recently hybrid wave maker which could be operated as not only piston type and/or flap type but also swing type wave maker have been devised by utilizing the link mechanism. The wave board of hybrid wave maker has been devised to be independently controlled by the horizontal actuators on upper and lower end of the wave board. The wave board could operate as a flap type wave board when the lower hinge is in a stationary condition and the upper hinge is operated with sinusoidal motion. On the contrary, the swing type wave board could be obtained by the lower hinge is activated and the upper hinge is in a stationary condition. When both end of the wave board is activated in a synchronized condition, the wave board motion become piston motion. In addition the hybrid wave maker could enhance the piston motion with flap motion or swing motion by selecting control parameters. Various wave board motion of hybrid wave maker and relevant wave form have measured on the wave board and departed location. It is appeared that the novel hybrid wave maker could be utilized for the improvement of wave qualities in experiments.

Swing Type and Batting Grip Affect Peak Pressures on the Hook of Hamate in Collegiate Baseball Players.

Background:Bat swing and grip type may contribute to hook of hamate fractures in baseball players.Purpose:To compare the effects of swing type and batting grip on the pressure and rate of pressure development over the hook of hamate in collegiate baseball players.Study Design:Descriptive laboratory study. Level of evidence, 3.Methods:This was an experimental quasi-randomized study of bat grip and swing differences in National Collegiate Athletic Association Division I baseball players (N = 14; age, 19.6 ± 1.1 years [mean ± SD]). All participants performed swings under 6 combinations: 3 grip types (all fingers on the bat shaft [AO], one finger off the bat shaft [OF], and choked up [CU]) and 2 swing types (full swing and check swing). Peak pressure and rate of pressure generation over the area of the hamate were assessed using a pressure sensor fitted to the palm of the bare hand over the area of the hamate. Wrist angular velocities and excursions of radial ulnar deviation were obtained using 3-dimensional motion analysis.Results:The OF–check swing combination produced the highest peak pressure over the hamate (3.72 ± 2.64 kg/cm2) versus the AO–full swing (1.36 ± 0.73 kg/cm2), OF–full swing (1.68 ± 1.17 kg/cm2), and CU–full swing (1.18 ± 0.96 kg/cm2; P < .05 for all). There was a significant effect of condition on rate of pressure development across the 6 conditions (P = .023). Maximal wrist angular velocities were 44% lower in all check swing conditions than corresponding full swing conditions (P < .0001). The time to achieve the maximal wrist angular velocity was longest with the AO–full swing and shortest with the CU–check swing (100.1% vs 7.9% of swing cycle; P = .014).Conclusion:The OF–check swing condition produced the highest total pressure reading on the hook of hamate. Check swing conditions also had the steepest rate of pressure development as compared with the full swing conditions.Clinical Relevance:Batters who frequently check their swings and use an OF or AO grip may benefit from bat modifications or grip adjustment to reduce stresses over the hamate. Athletic trainers and team physicians should be aware of these factors to counsel players in the context of previous or ongoing hand injury.

The Design and Optimization of Swing Automatic Paper Folding Mechanism

In order to solve the multi-directional bending problem of paper cards with different specifications, a swing type automatic paper folding mechanism was designed. Through gear rack mechanism and rocker slider mechanism, the paper card can be folded vertically and horizontally for many times. The MATLAB optimization function library is used to optimize the rocker, connecting rod, swing angle and other size parameters of the mechanism, and the swing angle of the bending block is determined to be 15 degrees. The motion equation of paper folding process is solved by vector equation and coordinate transformation, and kinematics simulation of swing paper folding mechanism is carried out by motion plug-in of SolidWorks. The simulation results show that the mechanism can meet the motion requirements of the waist seal, and the simulation parameters are consistent with the calculation parameters.

Super-Durable and Highly Efficient Electrostatic Induced Nanogenerator Circulation Network Initially Charged by a Triboelectric Nanogenerator for Harvesting Environmental Energy.

Triboelectric nanogeneration is a burgeoning and promising technology for harvesting low-frequency mechanical energy from the environment, but the energy conversion efficiency and service life of the triboelectric nanogenerator (TENG) device are limited by the inevitable frictional resistance between the tribo-surfaces. Herein, we propose an electrostatic induction nanogenerator (EING) circulation network (EICN) by integrating an arbitrary number of EING units for harvesting low-frequency mechanical energy. Because of absolute conquering of the friction resistance between the tribo-surfaces, the average power density of the EING device in the EICN by the initial charge injection (from a TENG or a power supply) is more than a 15-fold enhancement compared with the previous swing-structured TENG. The EICN can recover to the stable and optimal electrical output state in 90 s without external charge injection, even if the external triggering interrupts for 40 min and then restarts, demonstrating the excellent application feasibility of this strategy. To display the practical application scenario for harvesting large-scale mechanical energy from the environment, a high-performance and ultralow-friction TENG is designed for the initial charge injection to the EICN. Moreover, portable electronic devices are powered successfully to realize the self-powered sensing and remote marine environmental monitoring when an EICN with three EINGs is triggered by the real water wave. This EICN strategy not only can harvest low-frequency swing type mechanical energy but also has the capacity of harvesting the rotational mechanical energy after reasonable structure modification, providing an excellent candidate for large-scale blue energy harvesting in practical applications.

ОБЕСПЕЧЕНИЕ ВЗРЫВОБЕЗОПАСНОСТИ ЖИЛЫХ ДОМОВ

Purpose. The article describes constructive and technical solutions for preventing and reducing the consequences of household gas explosions in residential multi-apartment buildings equipped with a fixed gas supply system. Methods. The statistical data on household gas explosions in residential gasified multi-apartment buildings on the territory of Russia have been analyzed. The comparison of existing technical solutions and measures aimed at preventing an emergency explosion and reducing the explosion consequences (gas leak sensor, ventilation system, safety structures of the hinged and swing type) has been carried out. Findings. The data showing the timeliness of this problem due to the significant number of fatalities and large property damage have been obtained. In particular, during the period from 2017 to 2020, 37 explosions of household gas occurred in residential multi-apartment buildings, causing death of 61 people. Despite many positive aspects, the methods being currently used do not provide an adequate level of explosion safety, and therefore the authors see it appropriate to introduce measures aimed at reducing consequences in the event of gas explosion. One of such solutions is the use of a window opening as a safety structure. The main disadvantage, which does not allow us to consider blind glazing as a safety design, is the restriction on the glass thickness (4 mm). In addition, the drawback of using the given construction is low thermal insulation ability and high risk of causing damage to people near the building by glass fragments in the event of an explosion. This disadvantage of modern double-glazed windows can be eliminated by modifying the window frames with the help of special parts or weakened fasteners, which, if excessive pressure occurs, would ensure timely opening of the structure. An example includes safety structures on hinges, which have the ability to rotate these structures when exposed to excessive pressure. Another type of a safety construction is a swing safety design. At a given excess pressure on the working sash, the locking devices, which release the frame rotary sash, are triggered.Research application field. The results of the study can be used in the working out new technical solutions designed to prevent an emergency explosion and reduce the consequences of a potential explosion. Conclusions. The conducted research leads to the conclusion that further work is necessary to study the parameters of internal emergency explosions of household gas in residential buildings under various accident scenarios in order to develop optimal solutions to minimize the consequences of an explosion.

Phasor Measurement Unit Incorporated Adaptive Out-of-step Protection of Synchronous Generator

The existing out-of-step protection schemes have proven deficient in the prevention of significant outages. Out-of-step protection schemes must not operate in stable power swing and rapidly isolate an asynchronous generator or group of generators from the rest of the power system in case of unstable power swing. The paper proposes a novel phasor measurement unit (PMU) incorporated a polygon-shaped graphical algorithm for out-of-step protection of the synchronous generator. The unique PMU based logic works further to classify the type of swing once the graphical scheme detects it. The novel graphical logic scheme design in this work such that it can identify the complex power swing produced in the modern power system. The proposed algorithm can take the correct relaying decision in the event of power swing due to renewable integration, load encroachment, and transient faults. In this work, It uses the original and modified Kundur two area system with a power system stabilizer (PSS) to test the proposed algorithm. In the end, It provides assessment results of the proposed relay on the Indian grid system during the July-2012 blackout. The results declared that the proposed algorithm is fast, accurate, and adaptive in the modern power system and gives better performance than the existing out-of-step protection schemes.

골프 롱 퍼팅에서의 스윙 유형에 따른 거리감 차이 분석

[목적] 본 연구는 골프 롱 퍼팅에서의 스윙 유형에 따른 거리감의 차이를 분석하여 퍼팅 시 골퍼들의 거리감을 최적화시 키는 방법을 제시하기 위함이다. [방법] 본 연구를 위해 서울에 소재한 K대학교 골프연습장에서 퍼팅분석 장비인 Quintic Ball Roll을 이용하여 Kpga/Klpga 이상의 프로골퍼 10명과 핸디캡 18-27의 아마추어골퍼 10명을 대상으로 평지 스트레이 트라인 12미터 거리의 인조매트에서 미는 스윙 방법과 때리는 스윙 방법으로 각 10회씩 수행하였으며, 도출된 자료는 SPSS 20.0을 사용하여 T-test 분석을 하였다. [결과] 각 스윙방법이 퍼팅한 볼의 거리감에 미치는 영향을 확인한 결과, 프 로골퍼들의 경우 퍼팅방법과 롱 퍼팅 거리감은 유의미한 상관관계가 없는 것으로 확인되었으나, 비숙련 아마추어골퍼들 의 경우에는 미는 스윙으로 퍼팅할 때가 때리는 퍼팅으로 스윙할 때보다 롱퍼팅에서의 거리감 조절 능력이 높아지는 것 으로 나타났다. [결론] 따라서 비숙련 아마추어골퍼들은 롱 퍼팅에서는 미는 스윙으로 거리를 조절하는 퍼팅방법을 선택 하는 것이 바람직할 것으로 판단된다.

Symmetrical Fault Detection During Power Swing Using Mean Value of Sampled Data from the Current Signal

One of the most challenging events for distance relays is a transient phenomenon known as power swing, which can have damaging results to the system. The occurrence of power swing can cause the impedance trajectory to enter protective zones of distance relays that may lead them to the wrong operation. Malfunction of distance relays can create instability in power systems, and a large blackout may occur in these networks. The purpose of this paper is to introduce a new method based on using the mean value of sampled data from the current signal to recognize power swing from simultaneous faults. This method has been tested using DIgSILENT and MATLAB software on a two-bus network with parallel lines. The obtained results demonstrate that the proposed scheme is capable of detecting various types of power swings, including both unstable and stable power swing. The presented method in this paper also has an accurate operation to detect simultaneous symmetric faults. Besides, this method is planned for a protection system with a central controller using the IEC-61850 standard.

The sensitivity of commodity markets to exchange operations such as swing

A pricing model for the simplest commodity markets is considered. The model describes the behavior of the Order Book, consisting of orders from producers, consumers and speculators. The paper explores the external impact on this model in the form of large operations by new market participants, who at high speeds begin to push forward their orders, for example, first bids and then asks. Such strategies are called swings. This paper investigates a single cycle of one simple trading strategy of the swing type. Found a particular model case of pricing potentiality price relative to swing operation. An example is given, that shows that the simplest commodity markets with producers and consumers have the internal property that they are potentially vulnerable to external influences. The swinging of prices through large purchases and sales leads to systematic profits of the entrants at the expense of the traditional market participants.

Validation of Sensor-Based Game Analysis Tools in Tennis

Abstract Three inertial measurement unit (IMU) based tennis sensor systems from BABOLAT (PURE DRIVE PLAY, POP) and HEAD (Tennis Sensor) and a camera-based system (PlaySight) were tested with respect to the question whether the information about the number of strokes by swing type and spin type in training exercises and/or matches and the average as well as the maximum speed of the service per session are reliable. Subsequently, the question whether the mechanical properties of the BABOLAT PURE DRIVE PLAY racket are the same as the mechanical properties of the BABOLAT PURE DRIVE racket without IMU was addressed. For swing types in standard exercises the results are acceptable for forehand groundstrokes, backhand groundstrokes and services but not for volleys. In a match environment we find inacceptably high errors (&gt;10%) for the number of strokes for forehand and completely inacceptable levels for volley. The wrist-based IMU of BABOLAT POP has not reached an acceptable accuracy at all. For spin types the results are acceptable. The large variances in service speed assessment between devices make it doubtful whether any of them may be used for the control of training processes aiming at increasing the average service speed The mechanical properties of the BABOLAT rackets with and without IMU are quite the same.

Double continuation regions for American and Swing options with negative discount rate in Lévy models

AbstractIn this paper, we study perpetual American call and put options in an exponential Lévy model. We consider a negative effective discount rate that arises in a number of financial applications including stock loans and real options, where the strike price can potentially grow at a higher rate than the original discount factor. We show that in this case a double continuation region arises and we identify the two critical prices. We also generalize this result to multiple stopping problems of Swing type, that is, when successive exercise opportunities are separated by i.i.d. random refraction times. We conduct an extensive numerical analysis for the Black–Scholes model and the jump‐diffusion model with exponentially distributed jumps.

Mathematical and experimental analysis of the thermal effectiveness of an oscillating jet with side-to-side swing louvers in a cassette split type air conditioner

The impact of air supply control strategies (louvers movement) on indoor thermal environment were evaluated in this study. The temperature uniformity was evaluated by: (i) the air distribution performance index (ADPI) to determine the air diffusion performance in heating mode; (ii) the air draught rate (DR%) on the face to determine the local discomfort due to cold draught; (iii) the mathematically determined vertical temperature stratification in a room with Beta distributions. A comparison of the conventional type with three different oscillating type airflows (louvers swing angle ±20°, ±40° and ±60°) were experimentally analysed to determine appropriate air supply control strategies. The results indicated that Beta distributions could capture the overall trend of the oscillating airflow, to establish the acceptable thermal uniformity and higher thermal effectiveness. The oscillating airflow as generated by the side-to-side swing type delivery louvers mounted inside a cassette split type air conditioner could shorten heating time by 20% to attain room temperature from 9°C. The data reveal that oscillating airflow can provide a better thermal sensation to feeling warm in the heating mode at both ankle and neck level. The ADPI is approximately 85% in the occupied zone. The actual draught rates on the face ranged 0–35%.

Analisis Efisiensi Hasil Pencacahan Terhadap Tipe Pencacah Dan Material Sampah

Waste is one of the many social problems faced by the community. To solve the problem of waste required a technology to process waste itself. Several studies have been done, one of which is design and construction thrasher machine. There are several studies on the design and construction thrasher machine. However, the analysis was conducted on one type of thrasher machine with a particular waste material. This study aims to obtain the results of the efficiency analysis of the thrasher machine results on the type of thrasher machine and waste material. The method used is experimental method. The type of thrasher machine and waste material used as a free variable. The percentage of the chopping result is chosen as a variable depending on the speed of rotation and thrasher time as the companion variable. The results of this study based on the results of experiments, both qualitatively and quantitatively shows that plastic bottle trash has a suit with shear type, grass litter has a match with the type of swing and trash has a match with the type of crusher.

Hamstring Myoelectrical Activity During Three Different Kettlebell Swing Exercises.

Del Monte, MJ, Opar, DA, Timmins, RG, Ross, JA, Keogh, JWL, and Lorenzen, C. Hamstring myoelectrical activity during three different kettlebell swing exercises. J Strength Cond Res 34(7): 1953-1958, 2020-Kettlebell exercises have become an increasingly popular form of resistance training and component of lower-body rehabilitative training programs, despite a lack of scientific literature illustrating internal mechanisms and effectiveness of these approaches. Participants (n = 14) performed 3 different styles of kettlebell swings (hip hinge, squat, and double knee extension) and were assessed for medial hamstrings (MHs) and biceps femoris (BF) myoelectrical activity through surface electromyography (sEMG). Bipolar pregelled Ag/AgCl sEMG electrodes (10 mm diameter, 20 mm interelectrode distance) were placed on the participant's dominant limb after correct skin preparation. There was a main effect for swing type (p = 0.004), where the hip hinge swing elicited a greater overall MH and BF sEMG in comparison with the squat swing (mean difference = 3.92; 95% confidence interval [CI] = 1.53-6.32; p = 0.002) and the double knee extension swing (mean difference = 5.32; 95% CI = 0.80-9.83; p = 0.020). Across all swing types, normalized percentage of MH sEMG was significantly higher compared with the BF (mean difference = 9.93; 95% CI = 1.67-18.19; p = 0.022). The hip hinge kettlebell swing produced the greatest amount of hamstring sEMG for the 3 styles of kettlebell swings assessed. These findings have implications for the application of kettlebell swing exercises in strength and conditioning, injury prevention, and rehabilitation programs.

Purity of Plasma as a Sample for Neuropsychiatric Omics Studies Based on Virchow's Cellular Principle

As an idea to ensure the success of OMICS research, there is Virchow's pathological ideas of physical disease. This idea is that one cell, a group of cells, a substance, and a group of substances are specific for each disease. Based on this idea, it can be inferred that the unity and purity of the sample and the disease used are extremely important factors. In this study, the aim is to show how the difference in trivial centrifugal conditions of whole blood affected the plasma concentration of Phosphoethanolamine (PEA), a biomarker of depression shown in our previous study, It turned out that the value of PEA increases when the rotor is a swing type, or when the temperature at the time of centrifugation is set at 4°C. This increase might be due to platelet contamination in isolated plasma. Therefore, especially when the researchers are looking to discover an unknown marker, special attention should be paid to sample.

Strain Gage Sensor Based Golfer Identification Using Machine Learning Algorithms

To analyze golf player’s individual golf swing and improve their skills using computerized methods, recognizing the golf player’s personal swing is essential. In this study, the golf swing signal is acquired using high-precision strain gage sensor integrated into the golf club. We use four different types of classifiers to classify the golf players’ swing signals i.e. decision tree algorithms, discriminant analysis algorithms, support vector machine algorithms, and k-nearest neighbor classifiers. The best result is achieved by linear support vector machine with 100% testing accuracy and minimum time-cost. The classification results demonstrate that using machine learning algorithms is effective in recognizing golf player’s swing signature, and that the chosen strain gage sensor works well. This work presents the foundation for our future research in classifying different types of golf swings of the same golf player.