Split control and the Principle of Minimal Distance

2010 ◽  
pp. 211-244 ◽  
Author(s):  
Tomohiro Fujii
Keyword(s):  
Minimal Distance

Pattern Recognition in Histo-Pathology: Basic Considerations

1982 ◽  
Vol 21 (01) ◽  
pp. 15-22 ◽  
Author(s):  
W. Schlegel ◽  
K. Kayser
Keyword(s):  
Pattern Recognition ◽  
Graph Theory ◽  
Normal Tissue ◽  
Diagnostic Procedures ◽  
Minimal Distance ◽  
Malignant Growth ◽  
Colon Tissue ◽  
First Results ◽  
Tissue Structures ◽  
The Given

A basic concept for the automatic diagnosis of histo-pathological specimen is presented. The algorithm is based on tissue structures of the original organ. Low power magnification was used to inspect the specimens. The form of the given tissue structures, e. g. diameter, distance, shape factor and number of neighbours, is measured. Graph theory is applied by using the center of structures as vertices and the shortest connection of neighbours as edges. The algorithm leads to two independent sets of parameters which can be used for diagnostic procedures. First results with colon tissue show significant differences between normal tissue, benign and malignant growth. Polyps form glands that are twice as wide as normal and carcinomatous tissue. Carcinomas can be separated by the minimal distance of the glands formed. First results of pattern recognition using graph theory are discussed.

Role of magnetic resonance imaging in evaluating sphenoid sinus and internal carotid artery

2009 ◽  
Vol 123 (12) ◽  
pp. 1331-1337 ◽  
Author(s):  
H G Hatipoglu ◽  
M A Cetin ◽  
A Selvi ◽  
E Yuksel
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Carotid Artery ◽  
Internal Carotid Artery ◽  
Sphenoid Sinus ◽  
Carotid Arteries ◽  
Internal Carotid ◽  
Minimal Distance ◽  
Resonance Imaging ◽  
Internal Carotid Arteries

AbstractObjective:This study aimed to determine whether magnetic resonance imaging has a role in the evaluation of the sphenoid sinus and internal carotid artery. In addition, we aimed to establish reference measurements for the minimal distance between the internal carotid arteries.Method:The sphenoid sinuses and neighbouring internal carotid arteries of 90 patients were evaluated using sagittal T1-weighted and axial and coronal T2-weighted magnetic resonance images.Results:Sphenoid sinus pneumatisation was categorised as occipitosphenoidal (0 per cent), conchal (3.3 per cent), presellar (14.4 per cent) or sellar (82.2 per cent). The internal carotid artery protruded into the sphenoid sinus in 32.8 per cent, with a septum in 9.4 per cent. The incidence of sellar-type sphenoid sinus pneumatisation was higher in patients with protrusion of the internal carotid artery into the sphenoid sinus (p < 0.001). The incidence of presellar pneumatisation was higher in patients without internal carotid artery protrusion (p < 0.001). The minimal distance between the internal carotid arteries varied between 9.04 and 24.26 mm (mean, 15.94 mm).Conclusion:Magnetic resonance imaging can provide useful information about the sphenoid sinus and internal carotid artery, prior to endoscopic sphenoidotomy and trans-sphenoidal hypophysectomy.

scholarly journals A 2-DIMENSIONAL CELLULAR AUTOMATON FOR AGENTS MOVING FROM ORIGINS TO DESTINATIONS

2005 ◽  
Vol 16 (12) ◽  
pp. 1849-1860 ◽  
Author(s):  
NAJEM MOUSSA
Keyword(s):  
Cellular Automaton ◽  
Cluster Size ◽  
Bimodal Distribution ◽  
Minimal Distance ◽  
Time Step ◽  
Neighbor Site ◽  
Model Dynamics ◽  
Long Time ◽  
Freely Moving ◽  
Small Clusters

We develop a two-dimensional cellular automaton (CA) as a simple model for agents moving from origins to destinations. Each agent moves towards an empty neighbor site corresponding to the minimal distance to its destination. The stochasticity or noise (p) is introduced in the model dynamics, through the uncertainty in estimating the distance from the destination. The friction parameter "μ" is also introduced to control the probability that movement of all involved agents to the same site (conflict) is denied at each time step. This model displays two states; namely the freely moving and the jamming state. If μ is large and p is low, the system is in the jamming state even if the density is low. However, if μ is large and p is high, a freely moving state takes place whenever the density is low. The cluster size and the travel time distributions in the two states are studied in detail. We find that only very small clusters are present in the freely moving state, while the jamming state displays a bimodal distribution. At low densities, agents can take a very long time to reach their destinations if μ is large and p is low (jamming state); but long travel times are suppressed if p becomes large (freely moving state).

scholarly journals Minimal Distance-Based Generalisation Operators for First-Order Objects

2007 ◽  
pp. 169-183 ◽  
Author(s):  
Vicent Estruch ◽  
César Ferri ◽  
Jose Hernández-Orallo ◽  
María José Ramírez-Quintana
Keyword(s):  
Minimal Distance ◽  
First Order

scholarly journals Preoperative Assessment of the Feasibility of Pedicle Screw Insertion at the Proximal Thoracic Curve in Lenke Type 2 Idiopathic Scoliosis

2019 ◽  
Vol 10 (3) ◽  
pp. 261-265
Author(s):  
Yuki Taniguchi ◽  
Yoshitaka Matsubayashi ◽  
So Kato ◽  
Takashi Ono ◽  
Yasushi Oshima ◽  
...  
Keyword(s):  
Idiopathic Scoliosis ◽  
Cobb Angle ◽  
Pedicle Screw ◽  
Pedicle Screws ◽  
Preoperative Assessment ◽  
Japanese Patients ◽  
Minimal Distance ◽  
Screw Insertion ◽  
The Right

Study Design: Retrospective cohort study. Objectives: To investigate the feasibility of inserting pedicle screws in the proximal thoracic (PT) curve in Lenke type 2 idiopathic scoliosis, using post-myelography computed tomography (CT). Methods: Post-myelography CT images of 46 Japanese patients, 10 to 30 years old, who underwent surgery for Lenke type 2 idiopathic scoliosis were analyzed. A new parameter “SAPS” (space available for pedicle screw) was introduced, which defines the minimal distance between the lateral cortex of the pedicle and the spinal cord, with a SAPS <4.5 mm being “unacceptable.” All 460 pedicles (T2 through T6) were analyzed. Pedicle diameter was classified according to the Akazawa grading system. Results: Most pedicles on the right side at T3 (84.8%) and T4 (97.8%) were unacceptable. The unacceptable rate was 58.7% and 15.2% on the right side at T5 and T6, respectively. A larger Cobb angle of the PT curve was associated with a greater incidence of unacceptable SAPS at these levels. For a Cobb angle of the PT curve >40°, most right T5 pedicles were unacceptable. On the left side, most pedicles from T2 to T5 were acceptable. When T5 was the caudal end vertebra of the PT curve, the left T6 pedicles had an unacceptable SAPS in some cases. When the width of the pedicle channel was ≥2 mm (Akazawa grade 1 or 2), all pedicles from T2 to T6, on both sides, were acceptable. Conclusions: Post-myelography CT enabled us to clearly demonstrate the feasibility of inserting pedicle screws in the PT region.

An Energy Balanced Routing Hole and Network Partitioning Mitigation Model for Homogeneous Hierarchical Wireless Sensor Networks

2020 ◽  
Vol 12 (1) ◽  
pp. 28-42
Author(s):  
Nnaemeka Chiemezie Onuekwusi ◽  
Michael Chukwudi Ndinechi ◽  
Gordon Chiagozie Ononiwu ◽  
Onyebuchi Chikezie Nosiri
Keyword(s):  
Wireless Sensor Networks ◽  
Sensor Networks ◽  
Energy Dissipation ◽  
Cluster Head ◽  
Wireless Sensor ◽  
Switching Network ◽  
Minimal Distance ◽  
Network Partitioning ◽  
Energy Balancing ◽  
Hierarchical Wireless Sensor Networks

This article addresses the challenges of routing hole and network partitioning often experienced in hierarchical wireless sensor networks (WSNs). This developed model classifies network nodes into sets for effective energy management and formulates two cluster networks namely: switching and non-switching networks. Both networks are considered homogeneous and static WSNs and adopted approaches of residual energy, multi-hop and minimal distance as routing decision parameters. The switching network in addition introduces an energy switching factor as a major decision parameter for the switching of cluster head roles amongst cluster nodes. Network simulation was done using Truetime 2.0 and energy dissipation of the respective nodes and cluster heads was observed against a threshold. Results showed the introduction of the energy switching factor gave a significant energy balancing effect as nodes exhibited uniform energy dissipation. Furthermore, the residual energies for most nodes were above the threshold eliminating the possibility of the presence of routing hole and network partitioning.

scholarly journals Importance of Magnetic Effects in a Two-Flow Model for Extragalactic Radio Jets

1990 ◽  
Vol 140 ◽  
pp. 445-445
Author(s):  
H. Sol ◽  
G. Pelletier ◽  
E. Asseo
Keyword(s):  
Magnetic Field ◽  
Coming Out ◽  
Large Scale ◽  
Flow Model ◽  
Minimal Distance ◽  
Relativistic Electrons ◽  
Ambient Plasma ◽  
Relaxation Zone ◽  
Radio Jets ◽  
The Magnetic Field

We propose a model for extragalactic radio jets in which two different flows of particles are taken into account, (i) a beam of relativistic electrons and positrons extracted from the funnel of accretion disc and responsible for the observed superluminal motion, (ii) a classical or mildly relativistic wind of electrons and protons coming out from all parts of the disc (Sol et al., 1989). Studying the mutual interaction of the two flows, we show that the configuration is not destroyed by the plasma-beam instability as long as the magnetic field, assumed longitudinal, is strong enough, with an electron gyrofrequency ωc = eB/mec greater than the ambient plasma frequency ωp = (4πnpe2)1/2 (Pelletier et al., 1988). When ωc < ωp, the relativistic beam loses its energy and its momentum mainly through the development of strong Langmuir turbulence in the wind, and disappears quietly after some relaxation zone where heating and entrainment of the wind occur. This emphasizes one aspect of the important role likely played by the magnetic field in the dynamics of extragalactic jets and provides one example in which the magnetic field, acting on the microscopic scale of an interaction, induces strong effects on large–scale structures. Detailed data on the closest known superluminal radio source 3C120 (Walker et al., 1987, 1988; Benson et al., 1988) allow a check on the likelihood of our model. Observational estimates of the variation along the jet of the magnetic field and of the ambient plasma density np suggest that the magnetic field reaches its critical value (corresponding to ωc = ωp) at a minimal distance of about 1.4 kpc from the central engine. This is amazingly close to the location of the 4′–radio knot, a “rather curious structure” described by Walker et al. (1987), which we interpret as the beam relaxation zone in the context of our two–flow model (Sol et al., 1989).

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