Bis(2,6-dihy­droxy­benzoato-κ2 O 1,O 1′)(nitrato-κ2 O,O′)bis­(1,10-phenanthroline-κ2 N,N′)praseodymium(III)

The mononuclear title complex, [Pr(C7H5O3)2(NO3)(C12H8N2)2], is isostructural with related complexes of other lanthanides. The Pr(III) atom is in a pseudo-bicapped square-anti­prismatic geometry, formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and six O atoms, four from two 2,6-dihy­droxy­benzoate (DHB) ligands and the other two from nitrate anions. π–π stacking inter­actions between the phen and DHB ligands [centroid–centroid distances = 3.518 (2) and 3.778 (2) Å] and the phen and phen ligands [face-to-face separation = 3.427 (6) Å] of adjacent complexes stabilize the crystal structure. Intra­molecular O—H⋯O hydrogen bonds are observed in the DHB ligands

Bis(2,6-dihy­droxy­benzoato-κ2 O 1 ,O 1′)(nitrato-κ2 O,O′)bis­(1,10-phenanthroline-κ2 N,N′)europium(III)

The title mononuclear complex, [Eu(C7H5O3)2(NO3)(C12H8N2)2], is isostructural with those of other lanthanides. The Eu atom is in a pseudo-bicapped square-anti­prismatic geometry, formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and by six O atoms, four from two 2,6-dihy­droxy­benzoate (DHB) ligands and the other two from a nitrate anion. π–π stacking inter­actions between phen and DHB ligands [centroid–centroid distances = 3.5312 (19) and 3.8347 (16) Å], and between phen and phen ligands [face-to-face separation = 3.433 (4) Å] of adjacent complexes stabilize the crystal structure. Intra­molecular O—H⋯O hydrogen bonds are observed in the DHB ligands

Bis(2,6-dihy­droxy­benzoato-κ2 O 1 ,O 1′)(nitrato-κ2 O,O′)bis­(1,10-phenanthroline-κ2 N,N′)samarium(III)

The title mononuclear complex, [Sm(C7H5O3)2(NO3)(C12H8N2)2], is isostructural with that of other lanthanides. The Sm atom is in a pseudo-bicapped square-anti­prismatic geometry, formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and by six O atoms, four from two 2,6-dihy­droxy­benzoate (DHB) ligands and the other two from a nitrate anion. π–π stacking inter­actions between phen and DHB ligands [centroid–centroid distance = 3.528 (4) and 3.812 (3) Å], and phen and phen ligands [face-to-face separation = 3.420 (10) Å] of adjacent complexes stabilize the crystal structure. Intra­molecular O—H⋯O hydrogen bonds are observed in the DHB ligands

Energy-effective offloading scheme in UAV-assisted C-RAN system

In this paper, we aim to minimize the total power of all the Internet of Things devices (IoTDs) by jointly optimizing user association, computation capacity, transmit power, and the location of unmanned aerial vehicles (UAVs) in an UAV-assisted cloud radio access network (C-RAN). In order to solve this non-convex problem, we propose an effective algorithm by solving four subproblems iteratively. For the user association and the computation capacity subproblems, the non-convex constraints are relaxed and the optimal solutions are obtained. For the transmit power control and the location planning subproblems, successive convex approximation (SCA) technique is used to transform the non-convex constraints into convex ones. Moreover, to obtain the suboptimal solutions, slack variables are also introduced to deal with the feasibility-check problems. The simulation results demonstrate that the proposed algorithm can greatly reduce the total power consumption of IoTDs

An Efficient Algorithm to Identify Minimal Failure-Causing Schemas from Exhaustive Test Suite

Abstract-Combinatorial testing is widely used to detect failures caused by interactions among parameters for its efficiency and effectiveness. Fault localization plays an important role in this testing technique. And minimal failure-causing schema is the root cause of failure. In this paper, an efficient algorithm, which identifies minimal failure-causing schemas from existing failed test cases and passed test cases, is proposed to replace the basic algorithm with worse time performance. Time complexity of basic and improved algorithms is calculated and compared. The result shows that the method that utilizes the differences between failed test cases and passed test cases is better than the method that only uses the sub-schemas of those test cases

Bis(2,6-dihydroxybenzoato-κ2O1,O1′)(nitrato-κ2O,O′)bis(1,10-phenanthroline-κ2N,N′)cerium(III)

The mononuclear title complex, [Ce(C7H5O3)2(NO3)(C12H8N2)2], is isostructural to other related lanthanide structures. The Ce atom is in a pseudo-bicapped square-antiprismatic geometry formed by four N atoms from two chelating 1,10-phenanthroline (phen) ligands and by six O atoms, four from two 2,6-dihydroxybenzoate (DHB) ligands and the other two from a nitrate anion. π–π stacking interactions between phen and DHB ligands [centroid–centroid distances = 3.513 (3) and 3.762 (2) Å] and phen and phen ligands [face-to-face separation = 3.423 (7) Å] of adjacent complexes stabilize the crystal structure. Intramolecular O—H...O hydrogen bonds are observed in the DHB ligands

Data Rate Maximization in UAV-Assisted C-RAN

This letter considers the transmission design in unmanned aerial vehicle (UAV) assisted cloud radio access network (C-RAN). We aim to maximize data rate of the system by optimizing user equipment (UE) association, UAV placement, UEs' and UAVs' transmit power. We take UAVs as flying radio remote heads (RRHs) to serve UEs on the ground and maximize the sum rate of all the UEs. In order to solve this non-convex problem, we propose an iterative algorithm based on the successive convex approximation (SCA) and alternating iterative methods. The numerical results show that the proposed algorithm can effectively maximize the sum rate of UEs in the UAV assisted C-RAN system