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1.
Insulin pharmacokinetics is not well understood during continuous subcutaneous insulin infusion in type 2 diabetes (T2D). We analyzed data collected in 11 subjects with T2D [6 male, 9 white European and two of Indian ethnicity; age 59.7(12.1) years, BMI 30.1(3.9) kg/m2, fasting C-peptide 1002.2(365.8) pmol/l, fasting plasma glucose 9.6(2.2) mmol/l, diabetes duration 8.0(6.2) years and HbA1c 8.3(0.8)%; mean(SD)] who underwent a 24-h study investigating closed-loop insulin delivery at the Wellcome Trust Clinical Research Facility, Cambridge, UK. Subcutaneous delivery of insulin lispro was modulated every 15 min according to a model predictive control algorithm. Two complementary insulin assays facilitated discrimination between exogenous (lispro) and endogenous plasma insulin concentrations measured every 15–60 min. Lispro pharmacokinetics was represented by a linear two-compartment model whilst parameters were estimated using a Bayesian approach applying a closed-form model solution. The time-to-peak of lispro absorption (tmax) was 109.6 (75.5–120.5) min [median (interquartile range)] and the metabolic clearance rate (MCRI) 1.26 (0.87–1.56) × 10−2 l/kg/min. MCRI was negatively correlated with fasting C-peptide (rs = −0.84; P = .001) and with fasting plasma insulin concentration (rs = −0.79; P = .004). In conclusion, compartmental modelling adequately represents lispro kinetics during continuous subcutaneous insulin infusion in T2D. Fasting plasma C-peptide or fasting insulin may be predictive of lispro metabolic clearance rate in T2D but further investigations are warranted.  相似文献   

2.
In this study, we investigated a dependence of anionic species of ionic liquids (ILs) (IL: perfluoroalkyltrifluoroborate anions ([CnF2n+1BF3] (n = 0, 1, 2) and bis(perfluoroalkylsulfonyl)imide anions ([(CmF2m+1SO2)(CnF2n+1SO2)N] (m, n = 0, 1, 2)) on electrochemical and electromechanical properties. 1-Ethyl-3-methylimidazolium (EMI+) was selected as a cation for ILs. 1-Ethyl-3-methylimidazolium trifluoromethyltrifluoroborate (EMI[CF3BF3]), 1-ethyl-3-methylimidazolium pentafluoroethyltrifluoroborate (EMI[CF3CF2BF3]), 1-ethyl-3-methylimidazolium fluorosulfonyl(trifluoromethylsulfonyl)imide (EMI[FTA]) and 1-ethyl-3-methylimidazolium pentafluoroethylsulfonyl(trifluoromethylsulfonyl)imide (EMI[C1C2]) were synthesized according to the literatures. The generated strains of the bucky-gel electrodes of the actuators containing EMI[CF3BF3] (in the high frequency range: 10-0.5 Hz) and EMI[CF3CF2BF3] (in the high frequency range of 1-0.5 Hz) are larger than that containing EMI[BF4] (that is to say the quick response). For low frequencies (0.1-0.005 Hz), the generated strain containing EMI[CF3CF2BF3] was larger than those containing other ILs (EMI[CnF2n+1BF3] (n = 0, 1) and EMI[(CmF2m+1SO2)(CnF2n+1SO2)N] (m, n = 0, 1, 2)). The Young's modulus of actuators containing EMI[CF3BF3] and EMI[CF3CF2BF3] were 145 and 110 MPa, respectively. The melting points of EMI[CF3BF3] and EMI[CF3CF2BF3] are lower than that of EMI[BF4].Therefore, trifluoromethyltrifluoroborate ([CF3BF3]) and pentafluoroethyltrifluoroborate ([CF3CF2BF3]) anions performed much better as the actuator using the polymer-supported bucky-gel electrode containing the IL. These results are considered to be the actuator enough to apply actual applications (e.g. tactile display).  相似文献   

3.
In this paper, we introduce a new type of field—continuous sets, where we can exploit randomness in the non-repeating decimal expansions of irrationals for cryptographical purposes, and present two specific sets, a real interval [0, 1) and a functional space F[0, 1). On [0, 1), we propose ideal irrational random number generator (IIRNG) which generates non-repeating random number sequence as a truly RNG by computing the decimal expansion of an randomly chosen irrational. On F[0, 1), we propose integral encryption scheme (IES) with which we can encrypt an infinite message and obtain perfect security in one-time encryption by computing the integration of the message on a randomly chosen function. Either the seeds of IIRNG or the keys of IES are sufficiently safe and immune to exhaustive key search. Both IIRNG and IES require the assumption that an element of [0, 1) or F[0, 1) can be uniformly randomly chosen. Though the assumption cannot be achieved in classical finite machine, we present the discretization of the assumption, i.e., randomly choosing an element of U or V (the set of all possible methods of generating irrationals or functions). The immunity of seeds or keys to exhaustive key search still exists, since any finite search for a random element of U or V is inefficient. This is the basic idea of implementing IIRNG and IES in finite machine. Two corresponding examples IRNG and IBC are also presented, whose securities are guaranteed by the randomly chosen elements of U or V.  相似文献   

4.
A new class of fuzzy implications called the h-implications is introduced. They are implications generated from an additive generator of a representable uninorm in a similar way of Yager’s f- and g-implications which are generated from additive generators of continuous Archimedean t-norms and t-conorms. Basic properties of these implications are studied in detail. Modifications and generalizations of the initial definition are presented and their properties studied and compared between them. One of the modifications, called (he)-implications, is another example of a fuzzy implication satisfying the exchange principle but not the law of importation for any t-norm, in fact for any function F : [0, 1]2 → [0, 1].  相似文献   

5.
In Kingston and Svalbe [1], a generalized finite Radon transform (FRT) that applied to square arrays of arbitrary size N × N was defined and the Fourier slice theorem was established for the FRT. Kingston and Svalbe asserted that “the original definition by Matúš and Flusser was restricted to apply only to square arrays of prime size,” and “Hsung, Lun and Siu developed an FRT that also applied to dyadic square arrays,” and “Kingston further extended this to define an FRT that applies to prime-adic arrays”. It should be said that the presented generalized FRT together with the above FRT definitions repeated the known concept of tensor representation, or tensor transform of images of size N × N which was published earlier by Artyom Grigoryan in 1984-1991 in the USSR. The above mentioned “Fourier slice theorem” repeated the known tensor transform-based algorithm of 2-D DFT [5-11], which was developed for any order N1 × N2 of the transformation, including the cases of N × N, when N = 2r, (r > 1), and N = Lr, (r ≥ 1), where L is an odd prime. The problem of “over-representation” of the two-dimensional discrete Fourier transform in tensor representation was also solved by means of the paired representation in Grigoryan [6-9].  相似文献   

6.
A binary image I is Ba, Wb-connected, where ab ∈ {4, 8}, if its foreground is a-connected and its background is b-connected. We consider a local modification of a Ba, wb-connected image I in which a black pixel can be interchanged with an adjacent white pixel provided that this preserves the connectivity of both the foreground and the background of I. We have shown that for any (ab) ∈ {(4, 8), (8, 4), (8, 8)}, any two Ba, wb-connected images I and J each with n black pixels differ by a sequence of Θ(n2) interchanges. We have also shown that any two B4, W4-connected images I and J each with n black pixels differ by a sequence of O(n4) interchanges.  相似文献   

7.
Double-loop [J. Bermond, F. Comellas, D. Hsu, Distributed Loop Computer Networks: A Survey, J. Parallel and Distributed Computing, Academic Press, 24 (1995) 2-10] and 2-circulant networks (2-CN) [J. Park, Cycle Embedding of Faulty Recursive Circulants, J. of Korea Info. Sci. Soc. 31 (2) (2004) 86-94] are widely used in the design and implementation of local area networks and parallel processing architectures. In this paper, we investigate the routing of a message on circulant networks, that is a key to the performance of this network. We would like to transmit 2k packets from a source node to a destination node simultaneously along paths on G(n; ±s1, ±s2, … , ±sk), where the ith packet traverses along the ith path (1 ? i ? 2k). In order for all packets to arrive at the destination node quickly and securely, the ith path must be node-disjoint from all other paths. For construction of these paths, employing the Hamiltonian circuit latin square (HCLS), a special class of (n × n) matrices, we present O(n2) parallel routing algorithm on circulant networks.  相似文献   

8.
We propose two fast methods for dominant point detection and polygonal representation of noisy and possibly disconnected curves based on a study of the decomposition of the curve into the sequence of maximal blurred segments [2]. Starting from results of discrete geometry [3] and [4], the notion of maximal blurred segment of width ν[2] has been proposed, well adapted to possibly noisy curves. The first method uses a fixed parameter that is the width of considered maximal blurred segments. The second method is deduced from the first one based on a multi-width approach to obtain a non-parametric method that uses no threshold for working with noisy curves. Comparisons with other methods in the literature prove the efficiency of our approach. Thanks to a recent result [5] concerning the construction of the sequence of maximal blurred segments, the complexity of the proposed methods is O(n log n). An application of vectorization is also given in this paper.  相似文献   

9.
Accurate estimation of phytoplankton chlorophyll a (Chla) concentration from remotely sensed data is particularly challenging in turbid, productive waters. The objectives of this study are to validate the applicability of a semi-analytical three-band algorithm in estimating Chla concentration in the highly turbid, widely variable waters of Taihu Lake, China, and to improve the algorithm using a proposed four-band algorithm. The improved algorithm is expressed as [Rrs(λ1)− 1 − Rrs(λ2)− 1][Rrs(λ4)− 1 − Rrs(λ3)− 1]− 1. The two semi-analytical algorithms are calibrated and evaluated against two independent datasets collected from 2007 and 2005 in Taihu Lake. Strong linear relationships were established between measured Chla concentration and that derived from the three-band algorithm of [Rrs− 1(660) − Rrs− 1(692)]Rrs(740) and the four-band algorithm of [Rrs− 1(662) − Rrs− 1(693)][Rrs− 1(740) − Rrs− 1(705)]− 1. The first algorithm accounts for 87% and 80% variation in Chla concentration in the 2007 and 2005 datasets, respectively. The second algorithm accounts for 97% of variability in Chla concentration for the 2007 dataset and 87% of variation in the 2005 dataset. The three-band algorithm has a mean relative error (MRE) of 43.9% and 34.7% for the 2007 and 2005 datasets. The corresponding figures for the four-band algorithm are 26.7% and 28.4%. This study demonstrates the potential of the four-band model in estimating Chla even in highly turbid case 2 waters.  相似文献   

10.
The hypercube is one of the most versatile and efficient interconnection networks (networks for short) so far discovered for parallel computation. Let f denote the number of faulty vertices in an n-cube. This study demonstrates that when f ? n − 2, the n-cube contains a fault-free path with length at least 2n − 2f − 1 (or 2n − 2f − 2) between two arbitrary vertices of odd (or even) distance. Since an n-cube is a bipartite graph with two partite sets of equal size, the path is longest in the worst-case. Furthermore, since the connectivity of an n-cube is n, the n-cube cannot tolerate n − 1 faulty vertices. Hence, our result is optimal.  相似文献   

11.
Insects are important forest disturbance agents, and mapping their effects on tree mortality and surface fuels represents a critical research challenge. Although various remote sensing approaches have been developed to monitor insect impacts, most studies have focused on single insect agents or single locations and have not related observed changes to ground-based measurements. This study presents a remote sensing framework to (1) characterize spectral trajectories associated with insect activity of varying duration and severity and (2) relate those trajectories to ground-based measurements of tree mortality and surface fuels in the Cascade Range, Oregon, USA. We leverage a Landsat time series change detection algorithm (LandTrendr), annual forest health aerial detection surveys (ADS), and field measurements to investigate two study landscapes broadly applicable to conifer forests and dominant insect agents of western North America. We distributed 38 plots across multiple forest types (ranging from mesic mixed-conifer to xeric lodgepole pine) and insect agents (defoliator [western spruce budworm] and bark beetle [mountain pine beetle]). Insect effects were evident in the Landsat time series as combinations of both short- and long-duration changes in the Normalized Burn Ratio spectral index. Western spruce budworm trajectories appeared to show a consistent temporal evolution of long-duration spectral decline (loss of vegetation) followed by recovery, whereas mountain pine beetle plots exhibited both short- and long-duration spectral declines and variable recovery rates. Although temporally variable, insect-affected stands generally conformed to four spectral trajectories: short-duration decline then recovery, short- then long-duration decline, long-duration decline, long-duration decline then recovery. When comparing remote sensing data with field measurements of insect impacts, we found that spectral changes were related to cover-based estimates (tree basal area mortality [R2adj = 0.40, F1,34 = 24.76, P < 0.0001] and down coarse woody detritus [R2adj = 0.29, F1,32 = 14.72, P = 0.0006]). In contrast, ADS changes were related to count-based estimates (e.g., ADS mortality from mountain pine beetle positively correlated with ground-based counts [R2adj = 0.37, F1,22 = 14.71, P = 0.0009]). Fine woody detritus and forest floor depth were not well correlated with Landsat- or aerial survey-based change metrics. By characterizing several distinct temporal manifestations of insect activity in conifer forests, this study demonstrates the utility of insect mapping methods that capture a wide range of spectral trajectories. This study also confirms the key role that satellite imagery can play in understanding the interactions among insects, fuels, and wildfire.  相似文献   

12.
A closed interval is an ordered pair of real numbers [xy], with x ? y. The interval [xy] represents the set {i ∈ Rx ? i ? y}. Given a set of closed intervals I={[a1,b1],[a2,b2],…,[ak,bk]}, the Interval-Merging Problem is to find a minimum-cardinality set of intervals M(I)={[x1,y1],[x2,y2],…,[xj,yj]}, j ? k, such that the real numbers represented by equal those represented by . In this paper, we show the problem can be solved in O(d log d) sequential time, and in O(log d) parallel time using O(d) processors on an EREW PRAM, where d is the number of the endpoints of I. Moreover, if the input is given as a set of sorted endpoints, then the problem can be solved in O(d) sequential time, and in O(log d) parallel time using O(d/log d) processors on an EREW PRAM.  相似文献   

13.
Hardware implementation of multiplication in finite field GF(2m) based on sparse polynomials is found to be advantageous in terms of space-complexity as well as the time-complexity. In this paper, we present a new permutation method to construct the irreducible like-trinomials of the form (x + 1)m + (x + 1)n + 1 for the implementation of efficient bit-parallel multipliers. For implementing the multiplications based on such polynomials, we have defined a like-polynomial basis (LPB) as an alternative to the original polynomial basis of GF(2m). We have shown further that the modular arithmetic for the binary field based on like-trinomials is equivalent to the arithmetic for the field based on trinomials. In order to design multipliers for composite fields, we have found another permutation polynomial to convert irreducible polynomials into like-trinomials of the forms (x2 + x + 1)m + (x2 + x + 1)n + 1, (x2 + x)m + (x2 + x)n + 1 and (x4 + x + 1)m + (x4 + x + 1)n + 1. The proposed bit-parallel multiplier over GF(24m) is found to offer a saving of about 33% multiplications and 42.8% additions over the corresponding existing architectures.  相似文献   

14.
In this paper, the representations of fuzzy concepts based on raw data have been investigated within the framework of AFS (Axiomatic Fuzzy Set) theory. First, a brief review of AFS theory is presented and a completely distributive lattice, the E#I algebra, is proposed. Secondly, two kinds of E#I algebra representations of fuzzy concepts are derived in detail. In order to represent the membership functions of fuzzy concepts in the interval [0, 1], the norm of AFS algebra is defined and studied. Finally, the relationships of various representations with their advantages and drawbacks are analyzed.  相似文献   

15.
A new acoustic wave sensor to detect and quantify fluoride, one of the most hydrophilic anions, is proposed. Meso-octamethylcalix[4]pyrrole (OMCP) and seven of its derivatives were evaluated as piezoelectric quartz crystal coatings. Some of these sensors experienced appreciable coating leaching under a water flow, while others did show a very small sensitivity to fluoride. As the OMCP-naphthoquinone sensor was very sensitive to fluoride and did not lose a significant amount (α = 0.05) of coating during eight weeks, it was selected among all the others. A piezoelectric crystal coated with an amount of OMCP-naphthoquinone that produced a frequency decrease of 22 kHz showed a linear calibration range that extended up to 80 mg L−1, within which sensitivity to fluoride was 0.45 Hz L mg−1, and was able to detect fluoride at the concentration of 3.66 mg L−1. This sensor was used to determine fluoride in commercial fluoride tablets, and the result found was not statistically different (α = 0.05) from the value provided by the manufacturer.  相似文献   

16.
In this paper, we study the m-pancycle-connectivity of a WK-Recursive network. We show that a WK-Recursive network with amplitude W and level L is strictly (5 × 2L−1 − 2)-pancycle-connected for W ? 3. That is, each pair of vertices in a WK-recursive network with amplitude greater than or equal to 3 resides in a common cycle of every length ranging from 5 × 2L−1 − 2 to N, where N is the size of the interconnection network; and the value 5 × 2L−1 − 2 reaches the lower bound of the problem.  相似文献   

17.
The intent of this work is to look at the effects of varying the La2CuO4 electrode area and the asymmetry between the sensing and counter electrode in a solid state potentiometric sensor with respect to NOx sensitivity. NO2 sensitivity was observed at 500-600 °C with a maximum sensitivity of ∼22 mV/decade [NO2] observed at 500 °C for the sensor with a La2CuO4 electrode area of ∼30 mm2. The relationship between NO2 sensitivity and area is nearly parabolic at 500 °C, decreases linearly with increasing electrode area at 600 °C, and was a mixture of parabolic and linear behavior 550 °C. NO sensitivity varied non-linearly with electrode area with a minima (maximum sensitivity) of ∼−22 mV/decade [NO] at 450 °C for the sensor with a La2CuO4 electrode area of 16 mm2. The behavior at 400 °C was similar to that of 450 °C, but with smaller sensitivities due to a saturation effect. At 500 °C, NO sensitivity decreases linearly with area.We also used electrochemical impedance spectroscopy (EIS) to investigate the electrochemical processes that are affected when the sensing electrode area is changed. Changes in impedance with exposure to NOx were attributed to either changes in La2CuO4 conductivity due to gas adsorption (high frequency impedance) or electrocatalysis occurring at the electrode/electrolyte interface (total electrode impedance). NO2 caused a decrease in high frequency impedance while NO caused an increase. In contrast, NO2 and NO both caused a decrease in the total electrode impedance. The effect of area on both the potentiometric and impedance responses show relationships that can be explained through the mechanistic contributions included in differential electrode equilibria.  相似文献   

18.
Che-Nan Kuo 《Information Sciences》2010,180(15):2904-3675
A graph is said to be pancyclic if it contains cycles of every length from its girth to its order inclusive; and a bipartite graph is said to be bipancyclic if it contains cycles of every even length from its girth to its order. The pancyclicity or the bipancyclicity of a given network is an important factor in determining whether the network’s topology can simulate rings of various lengths. An n-dimensional folded hypercube FQn is an attractive variant of an n-dimensional hypercube Qn that is obtained by establishing some extra edges between the vertices of Qn. FQn for any odd n is known to be bipartite. In this paper, we explore the pancyclicity and bipancyclicity of FQn. For any FQn (n ? 2) with at most 2n − 3 faulty edges, where each vertex is incident to at least two fault-free edges, we prove that there exists a fault-free cycle of every even length from 4 to 2n; and when n ? 2 is even, we prove there also exists a fault-free cycle of every odd length from n + 1 to 2n − 1. The result is optimal with respect to the number of faulty edges tolerated.  相似文献   

19.
The n-dimensional folded hypercube FQn, a variation of the hypercube proposed by Ahmed et al. [A. El-Amawy, S. Latifi, Properties and performance of folded hypercubes, IEEE Transactions on Parallel and Distributed Systems 2(3) (1991) 31-42], is an (n + 1)-regular (n + 1)-connected graph. Conditional diagnosability, a new measure of diagnosability introduced by Lai et al. [Pao-Lien Lai, Jimmy J.M. Tan, Chien-Ping Chuang, Lih-Hsing Hsu, Conditional diagnosability measures for large multiprocessor systems, IEEE Transactions on Computers 54(2) (2005) 165-175] can better measure the diagnosability of regular interconnection networks. This paper determines that under PMC-model the conditional diagnosability of FQn (tc(FQn)) is 4n − 3 when n = 5 or n ? 8; tc(FQ3) = 3, tc(FQ4) = 7.  相似文献   

20.
Let V be a finite dimensional representation of a p -group, G, over a field,k , of characteristic p. We show that there exists a choice of basis and monomial order for which the ring of invariants, k [ V ]G, has a finite SAGBI basis. We describe two algorithms for constructing a generating set for k [ V ] G. We use these methods to analyse k [2V3 ]U3where U3is the p -Sylow subgroup ofGL3 (Fp) and 2 V3is the sum of two copies of the canonical representation. We give a generating set for k [2 V3]U3forp =  3 and prove that the invariants fail to be Cohen–Macaulay forp >  2. We also give a minimal generating set for k [mV2 ]Z / pwere V2is the two-dimensional indecomposable representation of the cyclic group Z / p.  相似文献   

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