Universal Dynamical Decoupling: Two-Qubit States and Beyond

Uhrig's dynamical decoupling pulse sequence has emerged as one universal and highly promising approach to decoherence suppression. So far both the theoretical and experimental studies have examined single-qubit decoherence only. This work extends Uhrig's universal dynamical decoupling from one-qubit to two-qubit systems and even to general multi-level quantum systems. In particular, we show that by designing appropriate control Hamiltonians for a two-qubit or a multi-level system, Uhrig's pulse sequence can also preserve a generalized quantum coherence measure to the order of $1+O(T^{N+1})$, with only $N$ pulses. Our results lead to a very useful scheme for efficiently locking two-qubit entangled states. Future important applications of Uhrig's pulse sequence in preserving the quantum coherence of multi-level quantum systems can also be anticipated.Comment: 10 pages, 4 figures, minor changes made, submitted to PR

Effect of farmyard manure on senescence, nitrogen and protein levels in leaves and grains of some cowpea vareities

The effect of farmyard manure was studied on senescence, nitrogen and protein content of the leaves and grains of cowpea. The experimental site for this study was situated at the International Institute of Tropical Agriculture (IITA), Kano Station, Nigeria. The cowpea varieties used in this experiment were Kanannado a local variety and IT89 KD – 288 an improved variety, two treatments were used for the experiment single manure treatment (manurexl), and double manure treatment (manurex2) at the ratio of 5:1 soil to manure and the control (no manure added). Plastic pots of 250mm diameter and 17.5cm for both length and height were used in this study. The pots were arranged in completely randomize block design and labeled appropriately using white and green plastic tags according to the plant treatment applied. The rainy season trial was carried out between August 2006 to November, 2006 while the dry season trial was carried out between October, 2007 to January, 2008 onset of senescence, days to 50% senescence, 90% senescence and days to total death of the plants occurred earlier in IT89KD – 288 than in Kanannado, while comparison between the treatments showed that senescence started earlier in plant treated with double manure treatment than those treated with single manure treatment. Between the two seasons, senescence started earlier rainy season than in dry season. On the other hand nitrogen and protein content of the leaves and grains were higher in IT89KD – 288 than in Kanannado, also between the treatment double manure treatment induced higher nitrogen protein content of leaves and grains. More nitrogen and protein, content of leaves and grains were obtained during the dry season trial than in the rainy season trial

Simulation analysis of ultrasonic testing in steel-based butt weld joint

Within this study, a simulation analysis based on Ultrasonic Testing (UT) is made using Comsol Multiphysics. Comsol Multiphysics is a software that can simplify many aspects of building UT method and also can be used to obtain a fast understanding of the results of altering the fundamental parameters. The software program has useful features which can help in technique development especially for UT inspectors in Non- destructive Testing (NDT) field. The focus of this study is to conduct a simulation analysis of internal weld defects by developing the model of defects in a weld structure sample configured using the software. The model is developed based on actual parameters and characterization of weld structure sample and internal weld defects. The results of analysis show that each type of defects which are incomplete penetration, slag inclusion and lack of fusion have different signal pattern and signal amplitude which are depended on the characterizations of those defects themselves

Community detection of political blogs network based on structure-attribute graph clustering model

Complex networks provide means to represent different kinds of networks with multiple features. Most biological, sensor and social networks can be represented as a graph depending on the pattern of connections among their elements. The goal of the graph clustering is to divide a large graph into many clusters based on various similarity criteria’s. Political blogs as standard social dataset network, in which it can be considered as blog-blog connection, where each node has political learning beside other attributes. The main objective of work is to introduce a graph clustering method in social network analysis. The proposed Structure-Attribute Similarity (SAS-Cluster) able to detect structures of community, based on nodes similarities. The method combines topological structure with multiple characteristics of nodes, to earn the ultimate similarity. The proposed method is evaluated using well-known evaluation measures, Density, and Entropy. Finally, the presented method was compared with the state-of-art comparative method, and the results show that the proposed method is superior to the comparative method according to the evaluations measures

Uji Efektivitas Jamur Antagonis Trichoderma SP. Dan Gliocladium SP. Untuk Mengendalikan Penyakit Lanas (Phytophthora Nicotianae) Pada Tanaman Tembakau Deli (Nicotiana Tabaccum L.)

The test of the effectiviveness of Trichoderma sp. and Gliocladium sp. antagonism fungi is aimed tocontrol lanas disease (Phytophthora nicotianae) in Deli tobacco plants (Nicotiana tabaccum L.). Theaim of the research was to know the effectiveness of Trichoderma sp. andGliocladium sp.antagonism fungi in controlling lanas disease in Deli tobacco plants. The research wasconducted at Tembakau Deli Research Center of PTPN II Sampali, Medan, from May untilSeptember, 2012. The research used non-factorial RAK (cluster random design) with ten treantmentsand three repetitions: control, P.nicotianae, 5 grams of Trichoderma sp., 10 grams of Trichoderma sp.,15 grams of Trichoderma sp., 20 grams of Trichoderma sp., 5 grams of Gliocladium sp.,10 grams of Gliocladium sp., 15 grams of Gliocladium sp., and 20 grams of Gliocladium sp. The resultof the research showed that the percentage of the highest attack was found in the treatment ofP.nicotianae (25.00%), but there was no symptom (0,00%) in the treatments of control,15 grams of Trichoderma sp., 20 grams of Trichoderma sp., 10 grams of Gliocladium sp.,15 grams of Gliocladium sp., and 20 grams of Gliocladium sp. The highest plant was found in thetreatment of 20 grams of Gliocladium sp. (50,92 centimeters) and the lowest plant was found in thetreatment of P.nicotianae (31,14 centimeters). The largest number of leaves was found in treatment of20 grams of Gliocladium sp. (20,18 leaves), and the smallest number of leaves was found in thetreatment of P.nicotianae (9,25 leaves). The result of the test of Trichoderma sp. and Gliocladium sp.antagonism fungi on P.nicotianae indicated that the growth of both fungi had rapidly developed so thatP.nicotianae tended to get away from antagonism at the media in the laboratory