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In this paper, an optimal energy management scheme for islanded building microgrid networks is proposed. The proposed building microgrid network comprises of several inter-connected building microgrids (BMGs) and an external energy supplier. Each BMG has a local combined heat and power (CHP) unit, energy storage, renewables and loads (electric and thermal). The external energy system comprises of an external CHP unit, chillers, electric heat pumps and heat pile line, for thermal energy storage. The BMGs can trade energy with other BMGs of the network and can also trade energy with the external energy supplier. In order to efficiently utilize the components of the BMGs and the network, the concept of adjustable power is adopted in this study. Adjustable power can reduce the operation cost of the network by increasing/decreasing the power of dispatchable units. In addition, the failure/recovery of components in the BMGs and the external system are also considered to analyze the performance of the proposed operation method. In order to optimally utilize the available resources during events, precedence among loads of BMGs and the external energy supplier is considered. Simulation results have proved the applicability of the proposed method for both normal islanded mode and with outage/recovery of equipment during the operation horizon. Finally, sensitivity analysis is carried out to analyze the impact of change in components&rsquo, parameters values on the saved cost of the network.

Let $D$ be a division ring with center $F$ and $N$ a subnormal subgroup of the multiplicative group $D^*$ of $D$. Assume that $N$ contains a non-abelian solvable subgroup. In this paper, we study the problem on the existence of non-abelian free subgroups in $N$. In particular, we show that if either $N$ is algebraic over $F$ or $F$ is uncountable, then $N$ contains a non-abelian free subgroup., 10 pages

In this paper, a multi-objective optimization method is proposed to determine trade-off between conflicting operation objectives of wind farm (WF) systems, i.e., maximizing the output power and minimizing the output power fluctuation of the WF system. A detailed analysis of the effects of different objective&rsquo, s weight values and battery size on the operation of the WF system is also carried out. This helps the WF operator to decide on an optimal operation point for the whole system to increase its profit and improve output power quality. In order to find out the optimal solution, a two-stage optimization is also developed to determine the optimal output power of the entire system as well as the optimal set-points of wind turbine generators (WTGs). In stage 1, the WF operator performs multi-objective optimization to determine the optimal output power of the WF system based on the relevant information from WTGs&rsquo, and battery&rsquo, s controllers. In stage 2, the WF operator performs optimization to determine the optimal set-points of WTGs for minimizing the power deviation and fulfilling the required output power from the previous stage. The minimization of the power deviation for the set-points of WTGs helps the output power of WTGs much smoother and therefore avoids unnecessary internal power fluctuations. Finally, different case studies are also analyzed to show the effectiveness of the proposed method.

The increased penetration of renewables is beneficial for power systems but it poses several challenges, i.e., uncertainty in power supply, power quality issues, and other technical problems. Backup generators or storage system have been proposed to solve this problem but there are limitations remaining due to high installation and maintenance cost. Furthermore, peak load is also an issue in the power distribution system. Due to the adjustable characteristics of loads, strategies on demand side such as demand response (DR) are more appropriate in order to deal with these challenges. Therefore, this paper studies how DR programs influence the operation of the multi-microgrid (MMG). The implementation is executed based on a hierarchical energy management system (HiEMS) including microgrid EMSs (MG-EMSs) responsible for local optimization in each MG and community EMS (C-EMS) responsible for community optimization in the MMG. Mixed integer linear programming (MILP)-based mathematical models are built for MMG optimal operation. Five scenarios consisting of single DR programs and DR groups are tested in an MMG test system to evaluate their impact on MMG operation. Among the five scenarios, some DR programs apply curtailing strategies, resulting in a study about the influence of base load value and curtailable load percentage on the amount of curtailed load and shifted load as well as the operation cost of the MMG. Furthermore, the impact of DR programs on the amount of external and internal trading power in the MMG is also examined. In summary, each individual DR program or group could be handy in certain situations depending on the interest of the MMG such as external trading, self-sufficiency or operation cost minimization.

In this paper, we study almost subnormal subgroups of the general linear group $\GL_n(D)$ of degree $n\ge 1$ over a division ring $D$ that satisfy a generalized power central group identity., Comment: 13 pages

Let $D$ be a non-commutative division ring, $G$ a subnormal subgroup of ${\mathrm GL}_n(D)$. In this note we show that if $G$ contains a non-abelian solvable maximal subgroup, then $n=1$ and $D$ is a cyclic algebra of prime degree over $F$., Comment: 9 pages

This paper deals with the real-time scheduling of a microgrid considering uncertainties of renewable energy sources (RESs). A two-step mathematical model based on real-time scheduling and demand responses (DRs) is proposed. DR programs, time of use (TOU) and emergency demand response programs (EDRP), are used to minimize the operation cost of microgrid. The proposed real-time scheduling is based on spinning and load reserves to deal with uncertainties of RESs. In the first step, the day-ahead scheduling is run for 24 hours with forecasted RESs. The second step deals with the actual RESs and the microgrid operation is rescheduled in the real time. The effectiveness of DR programs on the electrical demand for each interval is also shown in this study. The mixed-integer linear programming (MILP) method using CPLEX optimization program is used to solve the proposed two-step mathematical model.

This editorial to the summer 2015 AI Magazine introduces the special-issue articles on architectures for activity recognition and context-aware computing.

This study presents an experimental seasonal forecast of tropical cyclone (TC) activ- ity for Vietnam's coastal region during the 2012�2013 typhoon seasons, using the Regional Cli- mate Model (RegCM, version 4.2) to downscale the global Climate Forecasting System (CFS) fore- cast. Using an improved vortex tracking algorithm that detects vortex centers efficiently, RegCM reasonably forecasts the general distribution of TC counts in time as well as the TC track pattern during the entire experimental period from February to July 2012 and 2013, despite significant underestimation of the TC counts in the global CFS forecasts that are used as initial and lateral boundary conditions for the RegCM model. Further examination of the storm activity in the Viet- nam East Sea that directly influences Vietnam's coastal region shows, however, that RegCM tends to overestimate the TC frequency in this sub-region compared to observation. This suggests that direct applications of the RegCM model for seasonal forecasts of TC activity in Vietnam's coastal region has a significant bias that will need to be corrected before the model can provide useful information.

Introduction Performance status (PS) is the only known clinical predictor of outcome in patients with advanced non-small-cell lung cancer (NSCLC), although pharmacogenomic markers may also correlate with outcome. The aim of our study was to correlate clinical and pharmacogenomic measures with overall survival. Methods This was an IRB approved, retrospective study in which the medical records of 50 patients with advanced NSCLC from 1998–2008 were reviewed, and gender, race, PS, and chemotherapy regimens were documented. Stromal expression of pharmacogenomic markers (VEGFR, ERCC1, 14-3-3σ, pAKT, and PTEN) was measured. Clinical factors and pharmacogenomics markers were compared to overall survival using a Cox proportional hazards model. Results Forty patients received platinum-based therapy. Median age was 65 years. Improved PS, female gender, and gemcitabine therapy were significantly associated with longer overall survival ( P = 0.004, P = 0.04, and P = 0.003, respectively). Age was not associated with survival. Caucasians had better overall survival in comparison to African Americans with median survival of 14.8 months versus 10.4 months ( P = 0.1). Patients treated with platinum-based therapy had better survival of 15 months versus 8 months for non-platinum based therapy ( P = 0.01). There was no significant association between any of the pharmacogenomics markers and overall survival other than in patients treated with platinum, in whom ERCC1 negativity was strongly associated with longer survival ( P = 0.007). Conclusion ERCC1 negativity with platinum therapy, gemcitabine therapy, good PS, and female gender all correlated with improved overall survival in patients with advanced NSCLC.

Monitoring the status of existing devices and identification of newly added devices is required in microgrids to adjust the operation schedule followed by any event or integration of a new device. Therefore, in this paper, automatic reconfiguration of microgrids is considered after the addition of a new device or change in the operation status of an existing device by using a multiagent system. This capability of the microgrid is named as auto-configuration function, which is performed by the auto-configurator agent. In case of addition of a new device, the auto-configurator agent is responsible for authorization and registration of the newly added device. In case of change in status of any existing device, the status information is updated. After integration of a new device or change in status of an existing device, re-optimization is carried out by the energy management system (EMS) agent. Agent communication language (ACL) is used to develop a modified contract net protocol (MCNP) for communication among different agents. EMS agent and auto-configurator agent exchange information for economic rescheduling of the microgrid components. Simulation results have shown that the proposed method can be used for optimal operation of microgrids when the configuration changes due to the addition/removal of a device.

In distributed operation, each unit is operated by its local controller instead of using a centralized controller, which allows the action to be based on local information rather than global information. Most of the distributed solutions have implemented the consensus method, however, convergence time of the consensus method is quite long, while diffusion strategy includes a stochastic gradient term and can reach convergence much faster compared with consensus method. Therefore, in this paper, a diffusion strategy-based distributed operation of microgrids (MGs) is proposed using multiagent system for both normal and emergency operation modes. In normal operation, the MG system is operated by a central controller instead of the distributed controller to minimize the operation cost. If any event (fault) occurs in the system, MG system can be divided into two parts to isolate the faulty region. In this case, the MG system is changed to emergency operation mode. The normal part is rescheduled by the central controller while the isolated part schedules its resources in a distributed manner. The isolated part carries out distributed communication using diffusion between neighboring agents for optimal operation of this part. The proposed method enables peer-to-peer communication among the agents without the necessity of a centralized controller, and simultaneously performs resource optimization. Simulation results show that the system can be operated in an economic way in both normal operation and emergency operation modes.

Integration of demand response (DR) programs and battery energy storage system (BESS) in microgrids are beneficial for both microgrid owners and consumers. The intensity of DR programs and BESS size can alter the operation of microgrids. Meanwhile, the optimal size for BESS units is linked with the uncertainties associated with renewable energy sources and load variations. Similarly, the participation of enrolled customers in DR programs is also uncertain and, among various other factors, uncertainty in market prices is a major cause. Therefore, in this paper, the impact of DR program intensity and BESS size on the operation of networked microgrids is analyzed while considering the prevailing uncertainties. The uncertainties associated with forecast load values, output of renewable generators, and market price are realized via the robust optimization method. Robust optimization has the capability to provide immunity against the worst-case scenario, provided the uncertainties lie within the specified bounds. The worst-case scenario of the prevailing uncertainties is considered for evaluating the feasibility of the proposed method. The two representative categories of DR programs, i.e., price-based and incentive-based DR programs are considered. The impact of change in DR intensity and BESS size on operation cost of the microgrid network, external power trading, internal power transfer, load profile of the network, and state-of-charge (SOC) of battery energy storage system (BESS) units is analyzed. Simulation results are analyzed to determine the integration of favorable DR program and/or BESS units for different microgrid networks with diverse objectives.

In this paper, an optimal energy management strategy for a cooperative multi-microgrid system with combined cooling, heat and power (CCHP) is proposed and has been verified for a test case of building microgrids (BMGs). Three different demand types of buildings are considered and the BMGs are assumed to be equipped with their own combined heat and power (CHP) generators. In addition, the BMGs are also connected to an external energy network (EEN), which contains a large CHP, an adsorption chiller (ADC), a thermal storage tank, and an electric heat pump (EHP). By trading the excess electricity and heat energy with the utility grid and EEN, each BMG can fulfill its energy demands. Seasonal energy demand variations have been evaluated by selecting a representative day for the two extreme seasons (summer and winter) of the year, among the real profiles of year-round data on electricity, heating, and cooling usage of all the three selected buildings. Especially, the thermal energy management aspect is emphasized where, bi-lateral heat trading between the energy supplier and the consumers, so-called energy prosumer concept, has been realized. An optimization model based on mixed integer linear programming has been developed for minimizing the daily operation cost of the EEN while fulfilling the energy demands of the BMGs. Simulation results have demonstrated the effectiveness of the proposed strategy.

In this paper we study non-central almost subnormal subgroups of the multiplicative group of a division ring satisfying a non-zero generalized rational identity. The main result generalizes Chiba's theorem on subnormal subgroups. As an application, we get a theorem on almost subnormal subgroups satisfying a generalized algebraic rational identity. The last theorem has several corollaries which generalize completely or partially some previous results., Comment: 10 pages. arXiv admin note: text overlap with arXiv:1510.08720

Many recent studies have focused on satisfaction as one of key concepts in consumer behavior while dissatisfaction has received a much lesser attention. In services where failure is inevitable, customer satisfaction and dissatisfaction may be interwoven along the service buying/ using process. This study examines simultaneously the effect of four service attributes on customer satisfaction and dissatisfaction which lead to the word-of-mouth effect. SEM analysis based on a sample of 382 customers of package tour service reveals that staff attitude and failure recovery have positive effects on satisfaction, but not on dissatisfaction. Then, satisfaction, but not dissatisfaction has a positive impact on word-of-mouth. A negative correlation has also been found between satisfaction and dissatisfaction. Discussions and implications are presented along these statistical results.

Unit commitment of microgrids faces new challenges as the integration of demand response programs and renewable generation increases. In order to address these challenges, robust optimization is utilized for quantifying the impact of demand response uncertainty on the unit commitment of microgrids in this paper. Uncertainties in both shiftable (pricebased demand response) and curtailable (incentive-based demand response) loads are considered in this study. Initially, a cost-minimization deterministic model is formulated. Then, it is transformed to a min-max robust counterpart and finally, a tractable robust counterpart is formulated. The effects of uncertainty on trading power with the utility grid, operation cost, unit commitment of dispatchable generators, and state of charge of battery energy storage system are quantified. Simulations results have proved the robustness of proposed strategy.

The faults in a microgrid (MG) pose many challenges for operation of the system. They may lead to an increase in the operation cost. In this paper, in order to solve the problem, a novel algorithm based on the auto-configuration of MGs is proposed for minimizing the operation cost in grid-connected mode. A centralized energy management system (EMS) is also developed in accordance with the proposed algorithm, which is responsible for communication in the system and performs optimization. The EMS updates the system information and reschedules its resources upon occurrence of the faults or recovery from the faults for assuring economical operation of the MG system.

In this paper, a novel algorithm is proposed for optimal operation of microgrids considering the occurrence of faults or recovery from faults, auto-configuration. The objective of the proposed algorithm is to minimize the operation of the microgrid while ensuring stability. The auto-configuration is defined as the capability of the system to update the status of all components and reschedule healthy components, whenever a fault occurs or the system recovers from a fault. Additionally, an energy management system (EMS) is developed in accordance with the proposed algorithm to maintain the system frequency and operate the system in a cost-effective way.

We present a simple method of making multichannel photon counting measurements of weak lidar signal from large ranges, using commonly available USB-based digital storage oscilloscopes. The single photon pulses from compact photomultiplier tubes are amplified and stretched so that the pulses are large and broad enough to be sampled efficiently by the USB oscilloscopes. A software interface written in Labview is then used to count the number of photon pulses in each of the prescribed time bins to form the histogram of LIDAR signal. This method presents a flexible alternative to the modular multichannel scalers and facilitate the development of sensitive lidar systems.

In this paper, the authors present the sliding mode control problem of a structure using hedge-algebras-based fuzzy controller considering the impact of time delay (de-sHAC). Controlled model is a structure subjected to earthquake excitations. Numerical simulations are implemented in order to show advantages of the proposed controller. Obtained results include: variation of maximum displacement and maximum absolute acceleration versus time delay; time responses of displacement, absolute acceleration and control force of the structure in the uncontrolled case, the controlled case using the hedge-algebras-based fuzzy controller with input time delay (de-HAC) and the de-sHAC.

Civil society has been in operation under one-party rule in Vietnam in the years since the Doi Moi (renewal) in 1986. Despite the continued monopoly of political power by the Communist Party of Vietnam (CPV), civil society has been gradually expanded and developed. The paper reviews recent arguments in the political science and area studies literature on the emergence of civil society in Vietnam's Doi Moi period over the past two decades, to comment on the dynamics of the relationship between civil society and the party-state, problematizing the development of civil society in the context of a one-party-dominated state. At a certain level, civil society has been ‘tolerated’, ‘endorsed’, or recognized by the party state to fill a gap in the governance network. In practice, it has never been an easy project for civil society to make its way into Vietnamese society given the party-state's Gramscian concession to maintain the existing hegemony.

The performance of Global Satellite Mapping of Precipitation data (GSMaP_MVK, version 5.222.1) over the VuGia–ThuBon River basin and surrounding areas in central Vietnam was examined on a monthly basis in comparison with rainfall gauged at eight meteorological stations and a gridded rainfall product of the Asian Precipitation – HighlyResolved Observational Data Integration Towards Evaluation of Water Resources project (APHRODITE, V1003R1). APHRODITE represented in situ observations well, whereas GSMaP had very low performance over the study area for the period 2001–2007. Particularly, GSMaP exhibited large negative rainfall biases for the winter monsoon period from October to December and the biases tended to increase as the elevation decreased. A correction method using an artificial neural network (ANN) was implemented for the GSMaP rainfall over the VuGia–ThuBon River basin. Validation showed that the ANN correction method significantly improved the GSMaP quality in terms of spatial correlation, rainfall amplitude, and Nash–Sutcliffe efficiency coefficient for both the dependent period 2001–2005 and the independent period 2006–2007.

Cutaneous metastasis of visceral tumors accounts for 2% of skin tumors. We report the case of a 71-year-old male with a smoking history who presented to dermatology department with a violaceous nodule of the right sideburn skin. The lesion was interpreted as an adenocarcinoma that was completely excised and was suspicious for a metastasis. There was a recommendation for additional work-up. At a different institution, a positron emission tomography scan showed a left hilar mass and uptake in the right thyroid. He was then referred to our hospital for tissue diagnosis. Mediastinoscopy with biopsy of the left hilar mass showed metastatic follicular thyroid carcinoma. Subsequently, a thyroid fine needle aspirate showed suspicion for malignancy with similar morphology. Thyroidectomy and central neck dissection showed right thyroid papillary carcinoma extending to one margin and involving the lymph nodes. The left hilar metastasis mass resection showed similar lymph node findings. A re-review of the sideburn excision revealed similar histopathology to the thyroid and mediastinal resection. This case illustrates the opportunity of considering metastatic thyroid carcinoma to skin even in cases which lack the classic cytologic and architectural features of papillary thyroid carcinoma follicular variant.

In this paper, an optimal energy management scheme for building microgrids with rooftop greenhouse is proposed. A building energy management system (BEMS) is utilized for the optimal fulfilment of energy demands in the building and the greenhouse. The exhaust heat generated due to the operation of air conditioners in the building is used for fulfilling the cooling demands of the greenhouse via chillers. In addition to thermal and cooling demands, the four major control parameters (temperature, humidity, light intensity, and CO2 concentration) are also considered for optimal growth of crops in the greenhouse. A multi-agent system (MAS) is adopted to realize the interaction among several households of the building, the greenhouse, and the BEMS. The MAS comprises of several inner-level, intermediate level, and upper-level agents, which are responsible for their respective tasks. The performance of the proposed optimization strategy is evaluated for two seasons of a year, i.e., summer and winter. Numerical simulations have demonstrated the effectiveness of the proposed operation scheme for optimal operation of building microgrids with rooftop greenhouses.

We conducted a study to develop a transmitter consisting of two Distributed Feedback Dye Lasers (DFDL) using Rhodamine 6G as an active medium, pumped by a frequency-doubled Nd:YAG laser (5ns, 10 Hz, 532 nm). The BBO crystals are used for frequency-doubling of DFDLs to generate UV missions. This system has been set up and it generates selected wavelenghts at 282.9 nm and 286.4 nm with the energy of 30 \(\mu\)J/pulse and 60 \(\mu\)J/pulse respectively. A DIAL system using this UV transmitter is designed to measure the vertical distribution of ozone with high temporal and spatial resolution. Our simulations of received DIAL signal indicate that the altitude of ozone distribution measurement can reach to over 5000 m along with range resolution of 100 m.

Cirrus cloud is one of the most commonly occurring cloud types globally. The clouds are found mainly to consist of floating ice crystals, which can reflect strongly incoming radiation. Lidar measurements provide an opportunity to study the microphysics and ice compositions of cirrus clouds. We have developed a polarization lidar system to measure the depolarization characteristics of the lower atmosphere over Hanoi. From our measurements of cirrus clouds over the period from 2010 to 2012, the depolarization ratio of cirrus clouds is found to be very high ranging from 20% up to 80{\%}, indicating large fraction of backscattering from ice crystals. We find a trend of increasing depolarization ratio with height and decreasing temperature. We also compare our lidar measurements with other results obtained by lidar technique in other regions of the world.

Quantitative structure-retention relationship (QSRR) models were studied for two databases: one with 151 compounds and the other with 1719 compounds. In both cases, the three modeling methods employed (multiple linear regression, partial least squares, and random forests) provided similar prediction results with regard to root-mean-square error of prediction. The reversed-phase retention related seven molecular descriptors provided better models for the smaller dataset, while the use of over 2000 molecular descriptors generated better models for the larger dataset. The QSRR models were then validated with a mixture of an active pharmaceutical ingredient and its four process/degradation impurities. Finally, classification of compounds based on similar logD profiles before QSRR modeling improved chromatographic predictability for the models used. The results showed that database composition had a desirable effect on prediction accuracy for certain input molecules.

In this study, the retention behaviors of pharmaceutical and drug-like compounds in supercritical fluid chromatography (SFC) with polar stationary phases were evaluated using linear solvation energy relationships (LSERs). We used more than 200 compounds, including mono-, di-substituted benzenes, and other marketed drugs with a wide range of solvation descriptors. The dominant contribution to positive retention was the hydrogen bond donor acidity of the solutes, particularly for pyridine and amino columns. That factor is determined by the difference in basicity between the mobile and stationary phases. Another significant contributor to retention behavior was the hydrogen bond acceptor basicity of the solutes made particularly for diol and amino columns. The hydrogen bond donating ability is small for cyano and pyridine stationary phases (or should be zero) since those two phases lack hydrogen bond donor groups. The LSER results showed that the SFC retention behavior of compounds using carbon dioxide-methanol with polar stationary phases was close to that reported for normal phase LC using hexane-methanol. As expected, mobile phases containing high percentages of modifier resulted in decreased retention times for most compounds. A greater knowledge of the nature of solute/stationary phase and solute/mobile phase allows a more rapid and efficient choice in high-throughput screening of compound libraries.

We present an extensive, dynamic, and quantitative study of the root system architecture of Solanaceae based on 29 genotypes from three important groups (aubergines, capsicums, and tomatoes). Quantitative traits were essentially obtained from measurements made on high resolution images of different plant parts at several stages. The developmental schema was common to all genotypes. Several traits showed significant genetic variations: root apical diameter (reflecting meristem size), interbranch distances, slopes of the regression lines of elongation rate versus apical diameter, and ratios of diameters of laterals to mother roots. On all genotypes, the initial root system was complemented by a strong adventitious system emerging near the plant collar, made up of a set of fast growing roots with large apical diameters. Correlations between traits were evidenced within the root systems on one hand (e.g., interbranch distance and diameter ratio of laterals to their mother) and between shoot and root on the other hand (e.g., leaf area growth rate and root elongation rate). They revealed both trade-offs in developmental processes and coordination between plant parts. Beyond these results, we demonstrated the importance of characterizing phenotypes through multiple criteria, considering the whole plant and including late stages.

In this note, we introduce a new concept of a {\it generalized algebraic rational identity} to investigate the structure of division rings. The main theorem asserts that if a non-central subnormal subgroup $N$ of the multiplicative group $D^*$ of a division ring $D$ with center $F$ satisfies a non-trivial generalized algebraic rational identity of bounded degree, then $D$ is a finite dimensional vector space over $F$. This generalizes some previous results., Comment: 7 pages