1,528 research outputs found
Fixing number of co-noraml product of graphs
An automorphism of a graph is a bijective mapping from the vertex set of
to itself which preserves the adjacency and the non-adjacency relations of
the vertices of . A fixing set of a graph is a set of those vertices
of which when assigned distinct labels removes all the automorphisms of
, except the trivial one. The fixing number of a graph , denoted by
, is the smallest cardinality of a fixing set of . The co-normal
product of two graphs and , is a graph having the
vertex set and two distinct vertices are adjacent if is adjacent to
in or is adjacent to in . We define a general
co-normal product of graphs which is a natural generalization of the
co-normal product of two graphs. In this paper, we discuss automorphisms of the
co-normal product of graphs using the automorphisms of its factors and prove
results on the cardinality of the automorphism group of the co-normal product
of graphs. We prove that , for
any two graphs and . We also compute the fixing number of the
co-normal product of some families of graphs.Comment: 13 page
TSEP: Threshold-sensitive Stable Election Protocol for WSNs
Wireless Sensor Networks (WSNs) are expected to find wide applicability and
increasing deployment in near future. In this paper, we propose a new protocol,
Threshold Sensitive Stable Election Protocol (TSEP), which is reactive protocol
using three levels of heterogeneity. Reactive networks, as opposed to proactive
networks, respond immediately to changes in relevant parameters of interest. We
evaluate performance of our protocol for a simple temperature sensing
application and compare results of protocol with some other protocols LEACH,
DEEC, SEP, ESEP and TEEN. And from simulation results it is observed that
protocol outperforms concerning life time of sensing nodes used.Comment: 10th IEEE International Conference on Frontiers of Information
Technology (FIT 12), 201
Simulation Analysis of Medium Access Techniques
This paper presents comparison of Access Techniques used in Medium Access
Control (MAC) protocol for Wireless Body Area Networks (WBANs). Comparison is
performed between Time Division Multiple Access (TDMA), Frequency Division
Multiple Access (FDMA), Carrier Sense Multiple Access with Collision Avoidance
(CSMA/CA), Pure ALOHA and Slotted ALOHA (S-ALOHA). Performance metrics used for
comparison are throughput (T), delay (D) and offered load (G). The main goal
for comparison is to show which technique gives highest Throughput and lowest
Delay with increase in Load. Energy efficiency is major issue in WBAN that is
why there is need to know which technique performs best for energy conservation
and also gives minimum delay.Comment: NGWMN with 7th IEEE International Conference on Broadband and
Wireless Computing, Com- munication and Applications (BWCCA 2012), Victoria,
Canada, 201
Modeling Enhancements in DSR, FSR, OLSR under Mobility and Scalability Constraints in VANETs
Frequent topological changes due to high mobility is one of the main issues
in Vehicular Ad-hoc NETworks (VANETs). In this paper, we model transmission
probabilities of 802.11p for VANETs and effect of these probabilities on
average transmission time. To evaluate the effect of these probabilities of
VANETs in routing protocols, we select Dynamic Source Routing (DSR), Fish-eye
State Routing (FSR) and Optimized Link State Routing (OLSR). Framework of these
protocols with respect to their packet cost is also presented in this work. A
novel contribution of this work is enhancement of chosen protocols to obtain
efficient behavior. Extensive simulation work is done to prove and compare the
efficiency in terms of high throughput of enhanced versions with default
versions of protocols in NS-2. For this comparison, we choose three performance
metrics; throughput, End-to-End Delay (E2ED) and Normalized Routing Load (NRL)
in different mobilities and scalabilities. Finally, we deduce that enhanced DSR
(DSR-mod) outperforms other protocols by achieving 16% more packet delivery for
all scalabilities and 28% more throughput in selected mobilities than original
version of DSR (DSR-orig)
Successful Surgical and Medical Management of Cesarean Scar Pregnancy in 2 Patients
Background: Cesarean scar pregnancy (CSP), once a rare entity, is on the rise due because of an increase in the cesarean section rate worldwide. Currently, there is no standard protocol available for managing CSP. To contribute to the existing literature, this article presents the current authors' experience with 2 cases of CSP that were treated successfully with two different modalities. Cases: Case 1: A 34-year-old, gravida 2, para 1, was diagnosed with a CSP on initial transvaginal ultrasound (TVUS) scan at 6 weeks of gestation. Aspiration of the gestational sac and a local injection of methotrexate was performed. After 2 weeks, the gestational sac increased in size with thinning of the CS scar (1?mm), and plateauing of the ß?human chorionic gonadotropin (ß-hCG) occurred. Laparoscopic excision of the CSP and myometrial repair resulted in resolution. Case 2: A 31-year-old, gravida 3, para 1, achieved pregnancy after a frozen?thawed embryo transfer cycle. A TVUS scan, performed at 6 weeks of gestation showed a CSP. The patient's ß-hCG level was 310 mIU/mL. Systemic methotrexate was administered intramuscularly. The patient's ß-hCG on days 4 and 7 was 260 and 252, respectively. A repeat TVUS on day 7 showed a resolving gestational sac. A second dose of methotrexate resulted in complete resolution of the CSP. Results: The treatments (aspiration, methotrexate, and laparoscopic excision for Case 1, and methotrexate for Case 2) enabled resolution of the CSPs of these 2 patients. Conclusions: Various treatment modalities have been described for managing CSP with varied levels of success. When local injection of methotrexate into the gestational sac of CSP is unsuccessful, laparoscopic removal is safe and effective. Moreover, in the presence of low levels of ?-hCG, treatment with systemic methotrexate is usually successful. (J GYNECOL SURG 30:168)Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140096/1/gyn.2013.0131.pd
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