scholarly journals Effects of Abdominal Rotation on Jump Performance in the Ant Gigantiops destructor (Hymenoptera, Formicidae)

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Dajia Ye ◽  
Joshua C Gibson ◽  
Andrew V Suarez
Keyword(s):  
High Speed ◽  
Rotational Stability ◽  
Control Treatment ◽  
Maximum Height ◽  
Jump Performance ◽  
Future Studies ◽  
Rotational Momentum ◽  
And Control ◽  
Important Form ◽  
Leg Movements

Synopsis Jumping is an important form of locomotion, and animals employ a variety of mechanisms to increase jump performance. While jumping is common in insects generally, the ability to jump is rare among ants. An exception is the Neotropical ant Gigantiops destructor (Fabricius 1804) which is well known for jumping to capture prey or escape threats. Notably, this ant begins a jump by rotating its abdomen forward as it takes off from the ground. We tested the hypotheses that abdominal rotation is used to either provide thrust during takeoff or to stabilize rotational momentum during the initial airborne phase of the jump. We used high speed videography to characterize jumping performance of G. destructor workers jumping between two platforms. We then anesthetized the ants and used glue to prevent their abdomens from rotating during subsequent jumps, again characterizing jump performance after restraining the abdomen in this manner. Our results support the hypothesis that abdominal rotation provides additional thrust as the maximum distance, maximum height, and takeoff velocity of jumps were reduced by restricting the movement of the abdomen compared with the jumps of unmanipulated and control treatment ants. In contrast, the rotational stability of the ants while airborne did not appear to be affected. Changes in leg movements of restrained ants while airborne suggest that stability may be retained by using the legs to compensate for changes in the distribution of mass during jumps. This hypothesis warrants investigation in future studies on the jump kinematics of ants or other insects.

scholarly journals To the edge and beyond: How fast-response organizations adapt in rapidly changing crisis situations

2019 ◽  
pp. 001872671989345 ◽  
Author(s):  
Jan Kees Schakel ◽  
Jeroen Wolbers
Keyword(s):  
Information Sharing ◽  
High Speed ◽  
Process Model ◽  
Fast Response ◽  
Unexpected Events ◽  
Control Structures ◽  
Future Studies ◽  
Administrative Units ◽  
Police Cars ◽  
And Control

Fast-response organizations excel in mounting swift and coordinated responses to unexpected events. There are a multitude of conflicting explanations why these organizations excel. These range from acknowledging the strengths of centralized command and control structures, towards stressing the importance of decentralized, improvised action. Though this dichotomy is derived from studies offering either structure or action-based explanations, we were able to reconcile these insights by looking into the process of how fast-responders organize themselves during an unfolding crisis. We analyzed 15 high-speed police pursuits crossing multiple administrative units and jurisdictions, and interviewed and observed officers at work in multiple operations centers, police cars, and helicopters. Our analysis uncovered that fast-responders regularly transition between designed, frontline, and partitioned modes of organizing, each characterized by practices that shape command, allocation, and information sharing. Success and failure are rooted in the ability of the responders to adapt their mode of organizing by tacking back and forth between these practices. Based on our findings, we constructed a process model that provides a deeper understanding of fast-response organizing that informs future studies on organizing in extreme contexts.

Design and control of a high-speed direct-drive manipulator

1989 ◽  
Vol 27 (3) ◽  
pp. 375-394 ◽  
Author(s):  
K. YOUCEF-TOUMI ◽  
A. T. Y. KUO
Keyword(s):  
High Speed ◽  
Direct Drive ◽  
And Control

Effect of Slice Priority for admission control in 5G Wireless Networks: A comparison study for two Fuzzy-based systems considering Software-Defined-Networks

2020 ◽  
Vol 26 (3) ◽  
pp. 169-183
Author(s):  
Phudit Ampririt ◽  
Yi Liu ◽  
Makoto Ikeda ◽  
Keita Matsuo ◽  
Leonard Barolli ◽  
...  
Keyword(s):  
Wireless Networks ◽  
Admission Control ◽  
High Speed ◽  
Additional Parameter ◽  
Fifth Generation ◽  
Efficient Management ◽  
Grade Of Service ◽  
User Request ◽  
Control Decision ◽  
And Control

The Fifth Generation (5G) networks are expected to be flexible to satisfy demands of high-quality services such as high speed, low latencies and enhanced reliability from customers. Also, the rapidly increasing amount of user devices and high user’s requests becomes a problem. Thus, the Software-Defined Network (SDN) will be the key function for efficient management and control. To deal with these problems, we propose a Fuzzy-based SDN approach. This paper presents and compares two Fuzzy-based Systems for Admission Control (FBSAC) in 5G wireless networks: FBSAC1 and FBSAC2. The FBSAC1 considers for admission control decision three parameters: Grade of Service (GS), User Request Delay Time (URDT) and Network Slice Size (NSS). In FBSAC2, we consider as an additional parameter the Slice Priority (SP). So, FBSAC2 has four input parameters. The simulation results show that the FBSAC2 is more complex than FBSAC1, but it has a better performance for admission control.

scholarly journals The effect of mineral fertilisers and farmyard manure on grain and straw yield, quality and economical parameters of winter wheat

2020 ◽  
Vol 66 (No. 6) ◽  
pp. 249-256
Author(s):  
Lukáš Hlisnikovský ◽  
Milan Vach ◽  
Zdeněk Abrhám ◽  
Ladislav Mensik ◽  
Eva Kunzová
Keyword(s):  
Winter Wheat ◽  
Farmyard Manure ◽  
Market Price ◽  
Economic Benefits ◽  
Quality Parameters ◽  
Control Treatment ◽  
Yield Quality ◽  
Technology And Economy ◽  
And Control ◽  
Technological Methods

In the years 2011–2014, winter wheat grain yield, qualitative and economic parameters were evaluated according to different fertiliser treatments: (1) control: unfertilised treatment; (2) farmyard manure (FYM) and (3) FYM + NPK (farmyard manure applied together with mineral NPK). The highest yields (8.10 t/ha) were recorded in the FYM + NPK treatment, while significantly lower yields (6.20 t/ha and 5.73 t/ha) were recorded in FYM and control treatments, respectively. Similarly, statistically significantly higher values of the quality parameters were found in the FYM + NPK treatment (13.55% of crude protein content and 43.56 mL of Zeleny’s sedimentation test), compared to control (10% and 22.44 mL, respectively). The modelling expert system (AGROTEKIS-Crop Technology and Economy) was used for the evaluation of economy. This software is based on technological methods of cultivation and norms of material input costs and costs of individual mechanised works. The economic benefits and profitability were evaluated for three different levels of grain market price. The highest gross profit per ha was recorded in the FYM + NPK treatment. According to the gross profit, the control treatment provided better results than the FYM treatment.

Design, Construction and Control of a Remotely Operated Vehicle (ROV)

2011 ◽  
Author(s):  
Alireza Marzbanrad ◽  
Jalil Sharafi ◽  
Mohammad Eghtesad ◽  
Reza Kamali
Keyword(s):  
High Speed ◽  
Degrees Of Freedom ◽  
Remotely Operated Vehicle ◽  
Six Degrees Of Freedom ◽  
Depth Sensors ◽  
Control Schemes ◽  
On Line ◽  
Operation Unit ◽  
And Control ◽  
Design Construction

This is report of design, construction and control of “Ariana-I”, an Underwater Remotely Operated Vehicle (ROV), built in Shiraz University Robotic Lab. This ROV is equipped with roll, pitch, heading, and depth sensors which provide sufficient feedback signals to give the system six degrees-of-freedom actuation. Although its center of gravity and center of buoyancy are positioned in such a way that Ariana-I ROV is self-stabilized, but the combinations of sensors and speed controlled drivers provide more stability of the system without the operator involvement. Video vision is provided for the system with Ethernet link to the operation unit. Control commands and sensor feedbacks are transferred on RS485 bus; video signal, water leakage alarm, and battery charging wires are provided on the same multi-core cable. While simple PI controllers would improve the pitch and roll stability of the system, various control schemes can be applied for heading to track different paths. The net weight of ROV out of water is about 130kg with frame dimensions of 130×100×65cm. Ariana-I ROV is designed such that it is possible to be equipped with different tools such as mechanical arms, thanks to microprocessor based control system provided with two directional high speed communication cables for on line vision and operation unit.

A data acquisition and control system for high-speed gamma-ray tomography

2008 ◽  
Vol 19 (9) ◽  
pp. 094012 ◽  
Author(s):  
B T Hjertaker ◽  
R Maad ◽  
E Schuster ◽  
O A Almås ◽  
G A Johansen
Keyword(s):  
Control System ◽  
Data Acquisition ◽  
High Speed ◽  
Gamma Ray ◽  
And Control
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