Large quantum effects in the collinear F+H2-->FH+H reaction

We have performed accurate quantum mechanical calculations of reaction probabilities for the collinear F+H2-->FH+H reaction as well as corresponding quasiclassical trajectory calculations. A comparison of these results shows that very significant quantum mechanical effects are present in this reaction

A new neighborhood condition for graphs to be fractional (k,m)-deleted graphs

AbstractLet G be a graph of order n, and let k≥2 and m≥0 be two integers. Let h:E(G)→[0,1] be a function. If ∑e∋xh(e)=k holds for each x∈V(G), then we call G[Fh] a fractional k-factor of G with indicator function h where Fh={e∈E(G):h(e)>0}. A graph G is called a fractional (k,m)-deleted graph if there exists a fractional k-factor G[Fh] of G with indicator function h such that h(e)=0 for any e∈E(H), where H is any subgraph of G with m edges. In this paper, it is proved that G is a fractional (k,m)-deleted graph if δ(G)≥k+2m, n≥8k2+4k−8+8m(k+1)+4m−2k+m−1 and ∣NG(x)∪NG(y)∣≥n2 for any two nonadjacent vertices x and y of G such that NG(x)∩NG(y)≠0̸. Furthermore, it is shown that the result in this paper is best possible in some sense

A COMPARSION OF METHODS TO EXAMINE DOUBLE AND SINGLE LEG DROP JUMP PERFORMANCE

The purpose of this study was to compare the use of both a force platform and Optojump photocell system (Microgate, Bolzano, Italy) to examine double leg and single leg drop jumps. Thirteen physically active individuals performed 5 double leg drop jumps and 5 single leg drop jumps from a height of 0.3 m. Ground contact time (CT), flight height (FH) and reactive strength index (RSI) were calculated concurrently for both jump types. Despite intraclass correlation coefficients for all variables being very close to 1, a significant systematic difference was consistently observed between both devices with the Optojump system overestimating CT and underestimating both FH and RSI for both jump types. Both devices demonstrated excellent test- retest reliability with all ICCs for CT, FH and RSI above 0.940

Slow Frequency-Hopping Multicarrier DS-CDMA for Transmission over Nakagami Multipath Fading Channels

A novel multiple access scheme based on slow frequency hopping multicarrier direct-sequence code division multiple access (SFH/MC DS-CDMA) is proposed and investigated, which can be rendered compatible with the existing second-generation narrowband CDMA and third-generation wideband CDMA systems. The frequency hopping patterns are controlled by a set of constant-weight codes. Consequently, multirate communications can be implemented by selecting the corresponding sets of constant-weight codes having the required weights controlling the SFH patterns invoked. Two FH schemes, namely random and uniform FH, are considered and their advantages as well as disadvantages are investigated. We assume that the system operates in a multipath fading environment and a RAKE receiver structure with maximum ratio combining (MRC) is used for demodulation. The system’s performance is evaluated over the range of multipath Nakagami fading channels, under the assumption that the receiver has an explicit knowledge of the associated frequency-hopping (FH) patterns invoked. Furthermore, the performance of the SFH/MC DS-CDMA system is compared to that of the conventional single-carrier (SC) DS-CDMA system and that of the conventional MC DS-CDMA system, under the assumptions of constant system bandwidth and of constant transmitted signal power. Index Terms—Code division multiple access, constant-weight code, frequency hopping, Nakagami fading, orthogonal frequency division multiplexing

Blind Joint Soft-Detection Assisted Slow Frequency-Hopping Multicarrier DS-CDMA

A novel multiple-access scheme based on slow frequency-hopping multicarrier direct-sequence, code-division multiple access (SFH/MC DS-CDMA) is proposed and investigated, which can be rendered compatible with the existing second-generation narrow-band CDMA and third-generation wide-band CDMA systems. Blind joint soft-detection of the SFH/MC DS-CDMA signals is investigated, assuming that the receiver has no knowledge of the associated frequency-hopping (FH) patterns invoked. The system’s performance is evaluated over the range of Nakagami multipath fading channels. The results show that blind joint soft-detection achieves the required bit-error rate performance, while blindly acquiring the FH patterns employed. This is advantageous during the commencement of communications or during soft handover. Index Terms—Blind detection, code-division multiple access, constant-weight codes, frequency-hopping, orthogonal frequency-division multiplexing

Groups with compact open subgroups and multiplier Hopf ∗^*-algebras

For a locally compact group $G$ we look at the group algebras $C_0(G)$ and $C_r^*(G)$, and we let $f\in C_0(G)$ act on $L^2(G)$ by the multiplication operator $M(f)$. We show among other things that the following properties are equivalent: 1. $G$ has a compact open subgroup. 2. One of the $C^*$-algebras has a dense multiplier Hopf $^*$-subalgebra (which turns out to be unique). 3. There are non-zero elements $a\in C_r^*(G)$ and $f\in C_0(G)$ such that $aM(f)$ has finite rank. 4. There are non-zero elements $a\in C_r^*(G)$ and $f\in C_0(G)$ such that $aM(f)=M(f)a$. If $G$ is abelian, these properties are equivalent to: 5. There is a non-zero continuous function with the property that both $f$ and $\hat f$ have compact support.Comment: 23 pages. Section 1 has been shortened and improved. To appear in Expositiones Mathematica

Characterization of volcanic thermal anomalies by means of sub-pixel temperature distribution analysis

Abstract: The simultaneous solution of the Planck equation (involving the widely used “dual-band” technique) using two shortwave infrared (SWIR) bands allows for an estimate of the fractional area of the hottest part of an active lava flow (fh), and the background temperature of the cooler crust (Tc). The use of a high spectral and spatial resolution imaging spectrometer with a wide dynamic range of 15 bits (DAIS 7915) in the wavelength range from 0.501 to 12.67 µm resulted in the identification of crustal temperature and fractional areas for an intra-crater hot spot at Mount Etna, Italy. This study indicates the existence of a relationship between these Tc and fh extracted from DAIS and Landsat TM data. When the dual band equation system is performed on a lava flow, a logarithmic distribution is obtained from a plot of the fractional area of the hottest temperature versus the temperature of the cooler crust. An entirely different distribution is obtained over active degassing vents, where increases in Tc occur without any increase in fh. This result indicates that we can use scatter plots of Tc vs. fh to discriminate between different types of volcanic activity, in this case between degassing vents and lava flows, using satellite thermal data