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151.
Given a set of M × N real numbers, can these always be labeled as xi,j; i = 1,…, M; j = 1,…, N; such that xi+1,j+1 ? xi+1,j ? xi,j+1 + xij ≥ 0, for every (i, j) where 1 ≤ i ≤ M ? 1, 1 ≤ j ≤ N ? 1? For M = N = 3, or smaller values of M, N it is shown that there is a “uniform” rule. However, for max(M, N) > 3 and min(M, N) ≥ 3, it is proved that no uniform rule can be given. For M = 3, N = 4 a way of labeling is demonstrated. For general M, N the problem is still open although, for a special case where all the numbers are 0's and 1's, a solution is given. 相似文献
152.
A generalized set of magnetization modes for quantifying cross-correlation contributions to longitudinal relaxation in strongly coupled spin systems is described in this paper. Such a set of modes (called longitudinal multiple-quantum modes) is used to unravel cross-correlation information in strongly coupled systems, where the strength of the J coupling tends to obscure such effects. The applicability of such methods is demonstrated for a small molecule which exhibits some strong coupling effects even at high magnetic field strengths. The contribution of "remote" cross correlations to the longitudinal relaxation of strongly coupled spins is detailed. Copyright 2000 Academic Press. 相似文献
153.
Shrawan Kumar 《Mathematische Annalen》2010,346(1):67-84
We extend the original Cachazo–Douglas–Seiberg–Witten conjecture on the structure of the chiral ring of classical supersymmetric Yang-Mills theory to symmetric spaces. 相似文献
154.
Sandra J. Rosenthal Ralph Jimenez Graham R. Fleming
P. V. Kumar
M. Maroncelli 《Journal of Molecular Liquids》1994,60(1-3):25-56We have investigated the ultrafast dynamics of methanol by time dependent fluorescent shift experiments and molecular dynamic simulations. The experiments were performed with two different probe molecules, 1-aminonaphthalene and coumarin 153. The molecular dynamic simulations employed these probes as well as small atomic and diatomic solutes. We find a previously unobserved fast decay component in the solvation response of methanol. The molecular dynamics results are in good agreement with this experimental result. The origin of this fast response and the linearity of the solvent response are discussed. 相似文献
155.
Dr. T. Krishna Kumar 《Mathematical Methods of Operations Research》1966,10(4):224-236
Summary In dealing with dynamic economic policy models one encounters optimization problems whose objective function is an integral of a linear function of a finite number of continuous variables and whose constraints are linear integral inequalities. A set of intertemporal efficiency conditions (equilibrium conditions) yielding the optimal policy are given. By approximating the continuous problem by a set of discrete problems and appealing to a well known convergence theorem in functional analysis a continuous analog of the duality theorem is proved.
The author is indebted to Mr.Arnold Faden for helpful suggestions and to ProfessorKarl A. Fox andGerhard Tintner for encouragement during the preparation of the paper. This research has been partially supported by a grant from the Ford Foundation to the School of Business Administration administered by the Center for Research in Management Science, University of California, Berkeley.
Vorgel. v.:G. Tintner. 相似文献
Zusammenfassung Bei der Beschäftigung mit dynamischen Modellen der ökonomischen Politik stößt man auf Optimierungsprobleme, deren Zielfunktion ein Integral einer linearen Funktion von einer endlichen Anzahl stetiger Variablen ist und deren Beschränkungen lineare Integral-Ungleichungen sind. Eine Menge intertemporaler Effizienz-Bedingungen (Gleichgewichtsbedingungen), die zur optimalen Politik führen, sind gegeben. Durch Approximation des kontinuierlichen Problems mittels einer Menge von diskreten Problemen und Berufung auf einen wohlbekannten Konvergenzsatz aus der Funktionalanalysis wird ein stetiges Analogon des Dualitätstheorems bewiesen.
The author is indebted to Mr.Arnold Faden for helpful suggestions and to ProfessorKarl A. Fox andGerhard Tintner for encouragement during the preparation of the paper. This research has been partially supported by a grant from the Ford Foundation to the School of Business Administration administered by the Center for Research in Management Science, University of California, Berkeley.
Vorgel. v.:G. Tintner. 相似文献
156.
An equivalent representation of the Spearman footrule is considered and a characterization in terms of a Markov chain is established. A martingale approach is thereby incorporated in the study of the asymptotic normality of the statistics. 相似文献
157.
A compact ultrafast terahertz (CUTE) free-electron laser (FEL) is being developed at the Raja Ramanna Centre for Advanced
Technology (RRCAT), Indore. The undulator required for the CUTE-FEL has recently been developed. We have designed, built and
characterized a variable gap, 5 cm period, 2.5 m long pure permanent magnet undulator in two identical segments. The tolerable
error in the magnetic field was 1% in rms, and we have measured it to be 0.7%. The obtained rms phase shake is around 2°.
To ensure that the trajectories do not have an exit error in position or angle, corrector coils have been designed. Shimming
coils have been applied for both the undulator segments to reduce the amplitude of the betatron oscillations in the vertical
trajectory. Details of novel corrector coils and soft iron shims are given and their performance is discussed.
相似文献
158.
In this contribution we report studies on the nature of binding of a small ligand/drug Nile blue (NB) with sodium dodecyl
sulfate (SDS) micelles, bis-(2-ethylehexyl) sulfosuccinate (AOT)/isooctane reverse micelles (RM) and a genomic DNA extracted
from Salmon sperm. With detailed steady state and picosecond resolved optical spectroscopic techniques, we examined the fluorescence
quenching of the ligand upon complexation with the SDS monomers and DNA. Polarization analyzed picosecond-resolved fluorescence
measurements reveal geometrical restriction on the probe in SDS micelles, AOT-RM and DNA. Steady state and time resolved studies
on the probe in nanocages of AOT RM with various degrees of hydration (w0) reveal the existence of NB as two distinct species namely, neutral and cationic. This study confirms that the emission of
NB in aqueous micelles and DNA solution is due to the cationic form of the drug. Our experiments clearly identified non-specific
electrostatic and intercalative modes of interaction of the probe with the DNA at lower and higher DNA concentrations respectively.
The nature of binding of NB in presence of the DNA and SDS micelles reveals that the binding affinity of the probe is higher
with the micelles than with the DNA. The complex rigidity of NB with DNA and its fluorescence quenching with DNA elucidate
a strong recognition mechanism between NB and DNA. 相似文献
159.
Neeraj Kumar Giri 《Optics Communications》2008,281(13):3547-3552
Upconversion emission and energy transfer processes in singly, doubly and triply doped tellurite glasses have been studied under 798 and 980 nm laser excitations. Emissions have been observed at 482, 544, 584, 655 nm and at 477, 655, 698, 800 nm corresponding to Tb3+: 5D4 → 7F6, 7F5, 7F4, 7FJ (J = 0, 1, 2, 3) and Tm3+: 1G4 → 3H6, 1G4 → 3F4, 3F3 → 3H6, 3H4 → 3H6 transitions, respectively. Among Tm3+, Yb3+and Tb3+ ions only Tm3+ has a ground state absorption at 798 nm excitation due to 3H4 ← 3H6 transition. For 980 nm excitation only Yb3+ can absorb the incident radiation. However, for both types of excitations, emission from all the three ions Tb, Yb and Tm has been observed. Possible mechanisms are proposed as follows: under 798 nm excitation Tm3+ ions are excited which excite Yb3+ ions through energy transfer. Finally “cooperative energy transfer” from a pair of Yb3+ ions to Tm3+ and Tb3+ ions takes place. Under 980 nm excitation Yb3+ ions absorb the incident energy and excite Tm3+ and Tb3+ ions via cooperative energy transfer. Variation of emission intensity with the ion concentrations of Yb3+, Tm3+ and Tb3+ has been studied. The lifetime of the 1G4 level has also been measured. 相似文献
160.
Wireless Personal Communications - Privacy and security concerns are significant barrier for RFID deployment in many applications in modern day world. The implementation of authentication schemes... 相似文献