218 research outputs found
A Context Centric Model for building a Knowledge advantage Machine Based on Personal Ontology Patterns
Throughout the industrial era societal advancement could be attributed in large part to introduction a plethora of electromechanical machines all of which exploited a key concept known as Mechanical Advantage. In the post-industrial era exploitation of knowledge is emerging as the key enabler for societal advancement. With the advent of the Internet and the Web, while there is no dearth of knowledge, what is lacking is an efficient and practical mechanism for organizing knowledge and presenting it in a comprehensible form appropriate for every context. This is the fundamental problem addressed by my dissertation.;We begin by proposing a novel architecture for creating a Knowledge Advantage Machine (KaM), one which enables a knowledge worker to bring to bear a larger amount of knowledge to solve a problem in a shorter time. This is analogous to an electromechanical machine that enables an industrial worker to bring to bear a large amount of power to perform a task thus improving worker productivity. This work is based on the premise that while a universal KaM is beyond the realm of possibility, a KaM specific to a particular type of knowledge worker is realizable because of the limited scope of his/her personal ontology used to organize all relevant knowledge objects.;The proposed architecture is based on a society of intelligent agents which collaboratively discover, markup, and organize relevant knowledge objects into a semantic knowledge network on a continuing basis. This in-turn is exploited by another agent known as the Context Agent which determines the current context of the knowledge worker and makes available in a suitable form the relevant portion of the semantic network. In this dissertation we demonstrate the viability and extensibility of this architecture by building a prototype KaM for one type of knowledge worker such as a professor
Maximal Quantum Fisher Information in a Mach-Zehnder Interferometer without initial parity
Mach-Zehnder interferometer is a common device in quantum phase estimation
and the photon losses in it are an important issue for achieving a high phase
accuracy. Here we thoroughly discuss the precision limit of the phase in the
Mach-Zehnder interferometer with a coherent state and a superposition of
coherent states as input states. By providing a general analytical expression
of quantum Fisher information, the phase-matching condition and optimal initial
parity are given. Especially, in the photon loss scenario, the sensitivity
behaviors are analyzed and specific strategies are provided to restore the
phase accuracies for symmetric and asymmetric losses.Comment: 10 pages, 3 figure
Paleoenvironmental changes across the Late Cambrian–Early Ordovician in western Newfoundland
The Martin Point section (western Newfoundland, Canada) spans the uppermost Cambrian Broom Point and Martin Point members of the Green Point Formation (upper Furongian). The investigated interval (~ 90 m) consists of rhythmites of thinly-bedded marine carbonates (lime mudstones) alternating with green and black shale and thin conglomerate beds. Samples were extracted from the micritic carbonates and their preservation was petrographically and geochemically examined. The δ¹³Corg profile exhibits a positive shift (~ 2 ‰) associated with the globally well documented negative δ¹³Ccarb excursion at the HERB (Hellnmaria – Red Tops Boundary) and correlates with similar distinct shifts in the Al, Si, and ΣREE components, thus suggesting contributions from detrital organic matter relatively depleted in ¹²C likely induced by an eustatic sea-level drop and enhanced terrigenous inputs. Similarly, the δ¹⁵Norg variations are consistent with the proposed sea-level drop. This is also correlated with positive shifts on the Fe and Mn profiles reflecting overprinting of terrigenous inputs rather than reflecting the fluctuations in redox conditions
Synthese von mehrfach geladenen closo-Dodecaborat-Derivaten und borhaltigen Lipiden
The boron neutron capture therapy (BNCT) opens a fascinatingly perspective for cancer treatment. Non toxic or low toxic boron-containing compounds are used in BNCT. Therefore, the first part of the work is the synthesis of amphiphilic boron compounds. In particular, neutral and singly positively charged lipid-like compounds were synthesized. The second part of this work is the synthesis of a six negatively charged fluorescent boron compound
PREFENDER: A Prefetching Defender against Cache Side Channel Attacks as A Pretender
Cache side channel attacks are increasingly alarming in modern processors due
to the recent emergence of Spectre and Meltdown attacks. A typical attack
performs intentional cache access and manipulates cache states to leak secrets
by observing the victim's cache access patterns. Different countermeasures have
been proposed to defend against both general and transient execution based
attacks. Despite their effectiveness, they mostly trade some level of
performance for security, or have restricted security scope. In this paper, we
seek an approach to enforcing security while maintaining performance. We
leverage the insight that attackers need to access cache in order to manipulate
and observe cache state changes for information leakage. Specifically, we
propose Prefender, a secure prefetcher that learns and predicts attack-related
accesses for prefetching the cachelines to simultaneously help security and
performance. Our results show that Prefender is effective against several cache
side channel attacks while maintaining or even improving performance for SPEC
CPU 2006 and 2017 benchmarks.Comment: Submitting to a journa
Expression levels of TTF-1 and CyclinD1 and their relationship with lymphangiogenesis in ovarian cancer
Objective To investigate the expression levels of thyroid transcription factor-1 (TTF-1) and CyclinD1 in ovarian cancer and analyze their relationship with lymphangiogenesis. Methods The ovarian cancer tissue samples were collected from 60 patients with ovarian cancer and corresponding ovarian tissue samples from 20 patients pathologically diagnosed with benign ovarian tumors and normal ovarian tissue were collected as the control group. Tissue sections were prepared for immunohistochemical staining of TTF-1, CyclinD1 and D2-40. The staining results of TTF-1 and CyclinD1 were evaluated based on semi-quantitative integration method. D2-40 staining results were assessed according to Weidner evaluation method. Lymphatic vessel density (LVD) was calculated. Results The positive expression rates of TTF-1 and CyclinD1 were 58% and 83% in the ovarian cancer tissues, which were higher than 5% and 10% in the normal cancer tissues(all P < 0.001), respectively. The positive expression rates of TTF-1 and CyclinD1 were significantly increased in the ovarian cancer tissues with pathological stageⅢ-Ⅳ, lymph node metastasis, peritoneal metastasis, T3-T4 stage, N1 stage and M1 stage (all P < 0.05). Age and histological type were not correlated with the positive expression rates of TTF-1 and CyclinD1 (all P > 0.05). The LVD of ovarian cancer tissues with pathological stageⅢ-Ⅳ, lymph node metastasis and peritoneal metastasis was significantly increased (all P < 0.05). The LVD of ovarian cancer tissues with positive expression of TTF-1 and CyclinD1 was significantly higher than that of ovarian cancer tissues with negative expression (both P < 0.05). Conclusions TTF-1 and CyclinD1 are highly expressed in ovarian cancer tissues. Patients with severe ovarian cancer, lymphangiogenesis and metastasis have high expression of TTF-1 and CyclinD1, which may be potential new targets for ovarian cancer interventions
Optimization of Access Threshold for Cognitive Radio Networks with Prioritized Secondary Users
We propose an access control scheme in cognitive radio networks with prioritized Secondary Users (SUs). Considering the different types of data in the networks, the SU packets in the system are divided into SU1 packets with higher priority and SU2 packets with lower priority. In order to control the access of the SU2 packets (including the new arrival SU2 packets and the interrupted SU2 packets), a dynamic access threshold is set. By building a discrete-time queueing model and constructing a three-dimensional Markov chain with the number of the three types of packets in the system, we derive some performance measures of the two types of the SU packets. Then, with numerical results, we show the change trends for the different performance measures. At last, considering the tradeoff between the throughput and the average delay of the SU2 packets, we build a net benefit function to make optimization for the access threshold
Electric-field Control of Magnetism with Emergent Topological Hall Effect in SrRuO3 through Proton Evolution
Ionic substitution forms an essential pathway to manipulate the carrier
density and crystalline symmetry of materials via ion-lattice-electron
coupling, leading to a rich spectrum of electronic states in strongly
correlated systems. Using the ferromagnetic metal SrRuO3 as a model system, we
demonstrate an efficient and reversible control of both carrier density and
crystalline symmetry through the ionic liquid gating induced protonation. The
insertion of protons electron-dopes SrRuO3, leading to an exotic ferromagnetic
to paramagnetic phase transition along with the increase of proton
concentration. Intriguingly, we observe an emergent topological Hall effect at
the boundary of the phase transition as the consequence of the
newly-established Dzyaloshinskii-Moriya interaction owing to the breaking of
inversion symmetry in protonated SrRuO3 with the proton compositional
film-depth gradient. We envision that electric-field controlled protonation
opens a novel strategy to design material functionalities
Crohn’s Disease Treated by Chinese Medicine
Crohn’s disease is an inflammatory bowel disease with variable clinical symptoms, it can affect the whole gastrointestinal tract from the oral cavity to the anus and lead to lower quality of life and greater social and economicloss. Traditional Chinese medicine (TCM) has a long history and is unique characteristic by the theory of overall concept and treatment based on syndrome differentiation, it should be an important part of world medicine. This chapter introduces the research advance of Crohn’s disease in TCM, including its name, location, etiology and pathogenesis, syndrome differentiation, therapeutic criteria, treatment methods and other contents. The mechanism of TCM treatment of Crohn’s disease remains to be further studied
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