Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
2,8-Dimethyltricyclo[,9]dodecane-syn-2,syn-8-diol–propanoic acid (1/1)  [cached]
Yuji Mizobe,Roger Bishop,Donald C. Craig,Marcia L. Scudder
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809016547
Abstract: The racemic title compound, C14H24O2·C3H6O2, crystallizes in the monoclinic space group P21/c as a 1:1 diol/carboxylic acid cocrystal, A–B. The lattice incorporates infinite chains of the alcohol–carboxylic acid–alcohol supramolecular synthon, (...O—H...O=C(R)—O—H...O—H...), in which the hydrogen-bonded molecules (A—B—A)n surround a pseudo-threefold screw axis. The carboxylic acid group functions like an extended alcohol hydroxy group. Each diol, A, takes part in two such threefold screw arrangements, leading to a hydrogen-bonded layer structure, with adjacent layers containing diol molecules of opposite handedness. The central C atom of the propano bridge is disordered over two sites of occupancies 0.75 (1) and 0.25 (1). The methyl group of the propanoic acid molecule is disordered over two sites of occupancies 0.68 (1) and 0.32 (1).
Phenomenology of antigravity in N=2,8 supergravity  [PDF]
S. Bellucci
Physics , 1997,
Abstract: $N=2,8$ supergravity predicts antigravity (gravivector and graviscalar) fields in the graviton supermultiplet. Data on the binary pulsar PSR 1913+16, tests of the equivalence principle and searches for a fifth force yield an upper bound of order 1 meter (respectively, 100 meters) on the range of the gravivector (respectively, graviscalar) interaction. Hence these fields are not important in non-relativistic astrophysics (for the weak-field limit of $N=2,8$ supergravity) but can play a role near black holes and for primordial structures in the early universe of a size comparable to their Compton wavelengths.
Influence of Creaming and Ripening on the Aggregation Rate of Non-Ionic Dodecane-in-Water Nanoemulsions  [PDF]
Eliandreiina Cruz-Barrios,German Urbina-Villalba
Physics , 2014,
Abstract: The possible influence of creaming during the measurement of the aggregation rate of dodecane-in-water nanoemul- sions stabilized with Brij 30 is explored. For this purpose additional emulsions made with a neutral-buoyancy oil (bro- mo-dodecane) and mixtures of dodecane and Br-dodecane with squalene were synthesized. It is concluded that when the effect of ripening is suppressed, the influence of buoyancy on the evaluation of the flocculation rate is negligible. In the absence of squalene, ripening is present, and a sizeable difference in the flocculation rate of dodecane and bro- mo-dodecane is observed. However, this difference is not caused by the effect of gravity.
Grassmann Manifold G(2,8) and Complex Structure on $S^6$  [PDF]
Jianwei Zhou
Mathematics , 2006,
Abstract: In this paper, we use Clifford algebra and the spinor calculus to study the complex structures on Euclidean space $R^8$ and the spheres $S^4,S^6$. By the spin representation of $G(2,8)\subset Spin(8)$ we show that the Grassmann manifold G(2,8) can be looked as the set of orthogonal complex structures on $R^8$. In this way, we show that G(2,8) and $CP^{3}$ can be looked as twistor spaces of $S^6$ and $S^4$ respectively. Then we show that there is no almost complex structure on sphere $S^4$ and there is no orthogonal complex structure on the sphere $S^6$.
Stochastic Model of TCP SYN Attacks Stochastinis TCP SYN atak modelis  [cached]
Simona Ramanauskait?,Antanas ?enys
Science – Future of Lithuania , 2011, DOI: 10.3846/mla.2011.004
Abstract: A great proportion of essential services are moving into internet space making the threat of DoS attacks even more actual. To estimate the real risk of some kind of denial of service (DoS) attack in real world is difficult, but mathematical and software models make this task easier. In this paper we overview the ways of implementing DoS attack models and offer a stochastic model of SYN flooding attack. It allows evaluating the potential threat of SYN flooding attacks, taking into account both the legitimate system flow as well as the possible attack power. At the same time we can assess the effect of such parameters as buffer capacity, open connection storage in the buffer or filte-ring efficiency on the success of different SYN flooding attacks. This model can be used for other type of memory depletion denial of service attacks. Article in Lithuanian Vis didesn dalis svarbi paslaug persikelia internetin erdv , tod l did ja ir DoS atak potenciali gr sm . io tipo atak gr sm s vertinimui realiai sud tinga i bandyti galimai vyksian ias atakas, bet papras iau tai vertinti gali pad ti DoS atak matematiniai / programiniai modeliai. iame darbe ap velgiami egzistuojantys TCP SYN tipo atak modeliai bei siūlomas stochastinis modelis TCP SYN atakoms modeliuoti. Jis leid ia atsi velgi teis t sistemos sraut , galim atakos galingum , aukos naudojam apsaug savybes ir gali būti naudojamas ne tik TCP SYN, bet ir kitoms atminties i naudojimo DoS atakoms modeliuoti. Straipsnis lietuvi kalba
Cumulative Sum Algorithm for Detecting SYN Flooding Attacks  [PDF]
Tongguang Zhang
Computer Science , 2012,
Abstract: SYN flooding attacks generate enormous packets by a large number of agents and can easily exhaust the computing and communication resources of a victim within a short period of time. In this paper, we propose a lightweight method for detecting SYN flooding attack by non-parametric cumulative sum algorithm. We experiment with real SYN flooding attack data set in order to evaluate our method. The results show that our method can detect SYN flooding attack very well.
Development of a Surface Plasmon Resonance n-dodecane Vapor Sensor  [PDF]
Narcizo Mu?oz Aguirre,Lilia Martínez Pérez,Jose Alfredo Colín,Eduardo Buenrostro-Gonzalez
Sensors , 2007, DOI: 10.3390/s7091954
Abstract: Using a high density polyethylene thin film over gold layer, a Surface PlasmonResonance sensor for detecting n-dodecane vapor is developed. Preliminary results will bepresented, showing that samples in the range of a few hundred ppm(V) of n-dodecanevapor in butane gas can be sensed. Also, studying the response as a function of time, it isdemonstrated that the sensing process is quickly reversible.
Effects of the gravivector and graviscalar fields in N=2,8 supergravity  [PDF]
S. Bellucci,V. Faraoni
Physics , 1996, DOI: 10.1016/0370-2693(96)00317-6
Abstract: The available tests of the equivalence principle constrain the mass of the Higgs-like boson appearing in extended supergravity theories. We determine the constraints imposed by high precision experiments on the antigravity fields (gravivector and graviscalar) arising from $N=2,8$ supergravity.
Semiovals in PG(2,8) and PG(2,9)  [PDF]
Daniele Bartoli,Stefano Marcugini,Fernanda Pambianco
Mathematics , 2013,
Abstract: The classification of all semiovals and blocking semiovals in $\mathrm{PG}(2,8)$ and in $\mathrm{PG}(2,9)$ of size less than $17$ is determined. Also, some information on the stabilizer groups and the intersection sizes with lines is given.
An Active Defense Mechanism for TCP SYN flooding attacks  [PDF]
Saravanan Kumarasamy,A. Gowrishankar
Computer Science , 2012,
Abstract: Distributed denial-of-service attacks on public servers have recently become a serious problem. To assure that network services will not be interrupted and more effective defense mechanisms to protect against malicious traffic, especially SYN floods. One problem in detecting SYN flood traffic is that server nodes or firewalls cannot distinguish the SYN packets of normal TCP connections from those of a SYN flood attack. Another problem is single-point defenses (e.g. firewalls) lack the scalability needed to handle an increase in the attack traffic. We have designed a new defense mechanism to detect the SYN flood attacks. First, we introduce a mechanism for detecting SYN flood traffic more accurately by taking into consideration the time variation of arrival traffic. We investigate the statistics regarding the arrival rates of both normal TCP SYN packets and SYN flood attack packets. We then describe a new detection mechanism based on these statistics. Through the trace driven approach defense nodes which receive the alert messages can identify legitimate traffic and block malicious traffic by delegating SYN/ACK packets.
Page 1 /100
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.