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Industry 4.0, with its focus on flexibility and customizability, is pushing in the direction of wireless communication in future smart factories, in particular, massive multiple-input-multiple-output (MIMO) and its future evolution of large intelligent surfaces (LIS), which provide more reliable channel quality than previous technologies. At the same time, network slicing in 5G and beyond systems provides easier management of different categories of users and traffic, and a better basis for providing quality of service, especially for demanding use cases such as industrial control. In previous works, we have presented solutions for scheduling industrial control traffic in LIS and massive MIMO systems. We now consider the case of dynamic slicing in the radio access network, where we need to not only meet the stringent latency and reliability requirements of industrial control traffic, but also minimize the radio resources occupied by the network slice serving the control traffic, ensuring resources are available for lower-priority traffic slices. In this paper, we provide mixed-integer programming optimization formulations for radio resource usage minimization for dynamic network slicing. We tested our formulations in numerical experiments with varying traffic profiles and numbers of nodes, up to a maximum of 32 nodes. For all problem instances tested, we were able to calculate an optimal schedule within 1 s, making our approach feasible for use in real deployment scenarios. [ABSTRACT FROM AUTHOR]

Massive MIMO is one of the leading technologies for connecting very large numbers of energy-constrained nodes, as it offers both extensive spatial multiplexing and large array gain. A challenge resides in partitioning the many nodes into groups that can communicate simultaneously such that the mutual interference is minimized. Here we propose node partitioning strategies that do not require full channel state information, but rather are based on nodes' respective directional channel properties. In our considered scenarios, these typically have a time constant that is far larger than the coherence time of the channel. We developed both an optimal and an approximation algorithm to partition users based on directional channel properties, and evaluated them numerically. Our results show that both algorithms, despite using only these directional channel properties, achieve similar performance in terms of the minimum signal-to-interference-plus-noise ratio for any user, compared with a reference method using full channel knowledge. In particular, we demonstrate that grouping nodes with related directional properties is to be avoided. We hence realize a simple partitioning method, requiring minimal information to be collected from the nodes, and in which this information typically remains stable over the long term, thus promoting the system's autonomy and energy efficiency. [ABSTRACT FROM AUTHOR]

Cloud RAN (C-RAN) is a promising paradigm for the next generation radio access network infrastructure, which offers centralised and coordinated base-band signal processing in a cloud-based BBU pool. This requires extremely low latency responses to achieve real-time signal processing. In this paper, we analysed the challenges to introduce cloud native model for signal processing in C-RAN. We studied the difficulties of achieving real-time processing in a cloud infrastructure by addressing its latency-constraint. To evaluate the performance of such a system, we mainly investigated a massive MIMO pilot scheduling process in a C-RAN infrastructure under a factory automation scenario. We considered the stochastic delays incurred by the cloud execution environment as the main constraint that has has impact on the scheduling performance. We use simulations to provide insights on the feasibility of C-RAN deployment for industrial communication, which has stringent criteria to meet Industry 4.0 standards under this constraint. Our experiment results show that, concerning a pilot scheduling problem, the CRAN system is capable of meeting the industrial criteria when the fronthaul and the cloud execution environment has introduced latency in the order of milliseconds. [ABSTRACT FROM AUTHOR]

With the advancement of the next generation of cellular systems, flexible mechanisms for Discontinuous Reception (DRX) are needed in order to save energy. 5G will bring heterogeneous packet sizes and traffic types, as well as an increasing need for energy efficiency. The current static DRX mechanism is inadequate to meet these needs. In this paper we exploit channel prediction to develop integer programming models. We aim to minimize the energy usage of user devices while streaming video, as well as to create extended sleep opportunities, while simultaneously preventing buffer underflows. We also develop an online algorithm to obtain an efficient solution robust to prediction errors. Our results show that using a variable DRX cycle length can reduce the energy usage by up to 60 percent and 40 percent, in the offline and online cases, respectively, compared with a static DRX configuration. Our proposed online algorithm can also reduce the number of buffer underflows by up to 97 percent compared to the offline case. Both our online and offline solutions can provide extended DRX opportunities, which is required in 5G scenarios. [ABSTRACT FROM AUTHOR]

Massive multiple-input multiple-output (MIMO) is expected to be a vital component in future 5G systems. As such, there is a need for new modeling in order to investigate the performance of massive MIMO not only at the physical layer but also higher up the networking stack. In this paper, we present general optimization models for massive MIMO, based on mixed-integer programming and compatible sets, with both maximum ratio combining and zero-forcing precoding schemes. We then apply our models to the case of joint device scheduling and power control for heterogeneous devices and traffic demands, in contrast to the existing power control schemes that consider only homogeneous users and saturated scenarios. Our results show that substantial benefits, in terms of energy usage, can be achieved without sacrificing throughput and that both the signaling overhead and the complexity of end devices can be reduced by abrogating the need for uplink power control through efficient scheduling. [ABSTRACT FROM AUTHOR]

The technologies and culture of social media present issues for organisations implementing dialogic communication. The ubiquity of social media and the dialogic nature of communications in the digital age are raising awareness of the necessity of a total stakeholder approach to integrated communications. Yet, while the Marketing discipline argues that dialogic communication represent communication par excellence, this research finds that implementing a total stakeholder approach to dialogic communication is proving to be extremely elusive for many organisations exploring social media applications. The empirical findings of this research explore how marketing and communications professionals from a diverse range of industry and agency role contexts view social media, and presents issues that organisations face in implementing dialogic communication. It is suggested that these implementation issues inhibit the ability of organisations to move beyond ‘control’ and implement a total stakeholder approach to social media for dialogic communication that can engage with an organisation's stakeholders to gain their support. [ABSTRACT FROM PUBLISHER]

Non-melanomatous skin cancers represent 80% of all newly diagnosed cancers in Australia with basal cell carcinoma ( BCC) and squamous cell carcinoma ( SCC) being the most common. A previously healthy 71-year-old woman presented with widespread and tender superficial skin cancers on the lower bilateral limbs. External beam radiation therapy through the use of intensity-modulated radiation therapy ( IMRT) was employed as the treatment modality of choice as this technique provides conformal dose distribution to a three-dimensional treatment volume while reducing toxicity to surrounding tissues. The patient was prescribed a dose of 60 Gy to the planning target volume ( PTV) with 1.0 cm bolus over the ventral surface of each limb. The beam arrangement consisted of six treatment fields that avoided entry and exit through the contralateral limb. The treatment plans met the International Commission on Radiation Units and Measurements ( ICRU) guidelines and produced highly conformal dosimetric results. Skin toxicity was measured against the National Cancer Institute: Common Terminology Criteria for Adverse Events ( NCI: CTCAE) version 3. A well-tolerated treatment was delivered with excellent results given the initial extent of the disease. This case study has demonstrated the feasibility and effectiveness of IMRT for skin cancers as an alternative to surgery and traditional superficial radiation therapy, utilising a complex PTV of the extremities for patients with similar presentations. [ABSTRACT FROM AUTHOR]

Issues addressed: This paper presents a qualitative study of physical activity, eating and drinking experiences of children at Wellington Public School, NSW. The study was designed and implemented to inform school programs and policies with a goal of fostering a supportive and healthy environment at the school. Methods: The study involved use of focus groups, drawings and photovoice with 37 students from Kindergarten to Year 6 to determine problems, underlying causes and possible student-led interventions to enhance the school physical activity and nutritional environment. Results: Students considered play as related to fun games with friends. Sport was associated with structured, competitive types of physical activity. Infants class students preferred play, while primary students reported a preference for semi-structured and structured activities. Suggestions to improve school playing areas mirrored these preferences. The children suggested strategies for increasing fruit, vegetable and water consumption during the school day. Conclusion: The students were keen to explore ways to increase physical activity opportunities and develop a supportive nutritional environment at school. Simple, easy to implement suggestions were among the outcomes of the study, reinforcing the importance of including students' views in healthy school program and policy development. [ABSTRACT FROM AUTHOR]

Abstract: The first examples of complexes of the sterically crowded, bis(triphenylphosphine) auxiliary M(PPh3)2(η-C7H7) (M=Mo or W) have been synthesised. [Mo(CO)(PPh3)2(η-C7H7)][PF6] (1) was obtained by low-temperature reaction of [MoMe(CO)(PPh3)(η-C7H7)] with [Ph3C][PF6] in the presence of PPh3. The tungsten analogue [W(CO)(PPh3)2(η-C7H7)][BF4] (3) was formed by reaction of [WI(CO)(PPh3)(η-C7H7)] with Ag[BF4] in acetone followed by addition of PPh3. An X-ray crystallographic structural comparison of complex 3 with its mono-phosphine counterpart, [W(CO)2(PPh3)(η-C7H7)][BF4]·CH2Cl2 (4) reveals that the principal structural differences between 3 and 4 resulting from replacement of a carbonyl ligand by PPh3 are: (i) an increase in the sum of the angles between the tripodal ligands and (ii) an elongation of the W–PPh3 bond length (from 2.4950(12)Å in 4 to 2.5360(6) and 2.5496(6)Å in the bis(phosphine) complex 3). [Copyright &y& Elsevier]

We investigate the trade-off between energy usage and (packet) throughput in wireless mesh networks performing machine-to-machine communication. For this we provide a novel mixed-integer programming formulation to maximise the throughput while maintaining minimal energy usage, together with an effective price-and-branch solution algorithm based on column generation. The resulting optimisation model is the main original contribution of the presented paper. We conducted a numerical study using network examples from 10 to 40 nodes, in which periodic sensor measurements are aggregated and disseminated to actuators. In almost all cases, we were able to achieve maximum throughput and minimum energy usage simultaneously, and in those cases where this was not possible, the costs incurred in one objective in order to achieve the other were typically low. The solution times for all network sizes were of the order of seconds, showing that our optimisation model is feasible to use in practice. [ABSTRACT FROM AUTHOR]

The article focuses on the endeavours clauses and standard of care provision in the lighting industry in Great Britain.

The crystal structure of the title compound, C16H16N22+·2CF3O3S−, is the first structure to be reported for a diquaternized derivative of 2,9-dimethyl-1,10-phenanthroline. [ABSTRACT FROM AUTHOR]

The title structure, C18H20N22+·2CF3O3S−, is the first to be reported for a diquaternized derivative of 3,4,7,8-tetra­methyl-1,10-phenanthroline. [ABSTRACT FROM AUTHOR]

A series of molybdenum alkynyl complexes [Mo(CCR)(dppe)(η-C7H7)] featuring a range of alkynyl substituents R with varying electron-donating and -withdrawing properties have been prepared. Oxidation of representative members of the series to the corresponding 17-electron radical cations has been achieved through both chemical oxidation and in situ spectroelectrochemical methods. The largely metal-centered character of the HOMO in this class of compounds has been established through a combination of experimental measurements (IR, UV−vis−NIR, EPR spectroscopies) and DFT-based calculations and rationalized in terms of the stabilization of the metal dxy, dyz, dxz, and dx2-y2 through π- and δ-interactions with the C7H7 ring and concomitant destablization of the dz2 orbital. A series of molybdenum alkynyl complexes [Mo(CCR)(dppe)(η-C7H7)] featuring a range of alkynyl substituents R with varying electron-donating and -withdrawing properties have been prepared. Oxidation of representative members of the series to the corresponding 17-electron radical cations has been achieved through both chemical oxidation and in situ spectroelectrochemical methods. The largely metal-centered character of the HOMO in this class of compounds has been established through a combination of experimental measurements (IR, UV−vis−NIR, EPR spectroscopies) and DFT-based calculations and rationalized in terms of the stabilization of the metal dxy, dyz, dxz, and dx2-y2 through π- and δ-interactions with the C7H7 ring and concomitant destablization of the dz2 orbital. [ABSTRACT FROM AUTHOR]

The first examples of vinylidene complexes of the cycloheptatrienyl tungsten system [W(C=CHR)(dppe)(η-C₇H₇)](+) (dppe = Ph₂PCH₂CH₂PPh₂; R = H, 3; Ph, 4; C₆H₄-4-Me, 5) have been synthesised by reaction of [WBr(dppe)(η-C₇H₇)], 1, with terminal alkynes HC≡CR; a one-pot synthesis of 1 from [WBr(CO)₂(η-C₇H₇)] facilitates its use as a precursor. The X-ray structure of 4[PF₆] reveals that the vinylidene ligand substituents lie in the pseudo mirror plane of the W(dppe)(η-C₇H₇) auxiliary (vertical orientation) with the phenyl group located syn to the cycloheptatrienyl ring. Variable temperature ¹H NMR investigations on [W(C=CH₂)(dppe)(η-C₇H₇)][PF₆], 3, estimate the energy barrier to rotation about the W=C(α) bond as 62.5 ± 2 kJ mol⁻¹; approximately 10 kJ mol⁻¹ greater than for the molybdenum analogue. Deprotonation of 4 and 5 with KOBu(t) yields the alkynyls [W(C≡CR)(dppe)(η-C₇H₇)] (R = Ph, 6; C₆H₄-4-Me, 7) which undergo a reversible one-electron oxidation at a glassy carbon electrode in CH₂Cl₂ with E(½) values approximately 0.12 V negative of Mo analogues. The 17-electron radicals [6](+) and [7](+) have been investigated by spectroelectrochemical IR, UV-visible and EPR methods. The electronic structures of representative vinylidene (3) and alkynyl (6) complexes have been investigated at the B3LYP/Def2-SVP level. In both cases, electronic structure is characterised by a frontier orbital with significant metal d(z²)character and this dominates the structural and spectroscopic properties of the system.

The paramagnetic aryl-alkynyl complexes [Mo(C≡CAr)(dppe)(η-C(7)H(7))](+) (dppe = Ph(2)PCH(2)CH(2)PPh(2); Ar = C(6)H(5), [1](+); C(6)D(5), [2](+); C(6)H(4)-4-F, [3](+); C(6)H(4)-4-Me, [5](+)) and [Mo(C≡CBu(t))(dppe)(η-C(7)H(7))](+) [4](+), have been investigated in a combined EPR and ENDOR study. Direct experimental evidence for the delocalisation of unpaired spin density over the framework of an aryl-alkynyl ligand has been obtained. The X-band solution EPR spectrum of the 4-fluoro derivative, [3](+), exhibits resolved hyperfine coupling to the remote para position of the aryl group [a(iso)((19)F) = 4.5 MHz, (1.6 G)] in addition to couplings attributable to (95/97)Mo, (31)P and (1)H of the C(7)H(7) ring. A full analysis of the (1)H ENDOR spectra is restricted by the low g anisotropy of the system which prevents the use of orientation selection. However, inter-comparison of the (1)H cw-ENDOR frozen solution spectra of [1](+), [2](+), [4](+) and [5](+), combined with spectral simulation informed by calculated values derived from DFT investigations, has facilitated estimation of the experimental a(iso)((1)H) hyperfine couplings of [1](+) including the ortho, ±3.7 MHz (±1.3 G) and para, ±3.9 MHz (±1.4 G) positions of the C(6)H(5) substituent of the aryl-alkynyl ligand.

The synthesis, structural and magnetic characterisation of [V(III)(3)O(tmme)(2)(diimine)(2)Cl] [diimine=2,2'-bipyridine (1) or 1,10-phenanthroline (2)] and (HNEt(3))(2)[V(III)(4)O(tmme)(4)] (3) is reported, in which H(3)tmme is tris(mercaptomethyl)ethane, MeC(CH(2)SH)(3), the thiol analogue of the famous tripodal alcohol ligands typified by H(3)thme [tris(hydroxymethyl)ethane, MeC(CH(2)OH)(3)]. Complexes 1 and 3 have "T-shaped" and square topologies, respectively, and the latter is centred on a rare example of a square-planar oxide. The tri-thiolate ligands bind the periphery of the clusters and provide such strong antiferromagnetic exchange pathways that in both cases only a single total spin state is occupied up to room temperature, in the absence of metal-metal bonding. Magnetic data, electronic structure calculations and electrochemical data are reported.

The unprecedented spectroscopic and structural characterisation of a series of 17-electron, monometallic diynyl radicals, [Mo(C[triple bond]C-C[triple bond]CR)L(2)(eta-C(7)H(7))]*(+) (L(2) = bipy, R = SiMe(3); L(2) = dppe, R = SiMe(3) or H), are reported; the (L(2) = dppe, R = SiMe(3)) derivative is reactive to chain-centred C(beta)-C(beta') dimerisation.