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Estimations and applications of factor models often rely on the crucial condition that the number of latent factors is consistently estimated, which in turn also requires that factors be relatively strong, data are stationary and weakly serially dependent, and the sample size be fairly large, although in practical applications, one or several of these conditions may fail. In these cases, it is difficult to analyze the eigenvectors of the data matrix. To address this issue, we propose simple estimators of the latent factors using cross-sectional projections of the panel data, by weighted averages with predetermined weights. These weights are chosen to diversify away the idiosyncratic components, resulting in "diversified factors." Because the projections are conducted cross-sectionally, they are robust to serial conditions, easy to analyze and work even for finite length of time series. We formally prove that this procedure is robust to over-estimating the number of factors, and illustrate it in several applications, including post-selection inference, big data forecasts, large covariance estimation, and factor specification tests. We also recommend several choices for the diversified weights. for this article are available online. [ABSTRACT FROM AUTHOR]

Transmission lines are built to span over long distances, to which they are frequently exposed to many different situations that can cause abnormal conditions known as electrical faults. Electrical faults, when isolated, can cripple the transmission system as power flows are directed around these faults therefore leading to other numerous potential issues such as thermal and voltage violations, customer interruptions, or cascading events. Accurate fault classification and location is essential in reducing outage times and enhancing system reliability. Diverse methods exist and have different strengths and weaknesses. This paper aims to investigate the use of an intelligent technique based on artificial neural networks. The neural networks will attempt to determine the fault classification and precise fault location. Different fault cases are analyzed on multiple transmission line configurations using various phasor measurement arrangements from the two substations connecting the transmission line. The results can provide guidance on choosing the most efficient neural network structure and input measurements for transmission line fault classification and location. [ABSTRACT FROM AUTHOR]

To date, many efforts have been made to explore how to support driver's decision-making process with advisory information. Previous studies mainly focus on a single modality, e.g. the visual, auditory or haptic modality. In contrast, this study compares data from two simulator studies with 50 participants in total, where the visual vs. the auditory modality was used to present the same type of advisory traffic information under the same driving scenarios. Hereby we compare the effect of these two modalities on drivers' responses and driving performance. Our findings indicate that modality influences the drivers' behaviour patterns significantly. Visual information helps drivers to drive more accurately and efficiently, whereas auditory information supports quicker responses. This suggests that there are potential benefits in applying both modalities in tandem, as they complement each other. Correspondingly, we present several design recommendations on Advisory Traffic Information Systems. [ABSTRACT FROM AUTHOR]

In this article, we consider a high-dimensional quantile regression model where the sparsity structure may differ between two sub-populations. We develop ℓ1-penalized estimators of both regression coefficients and the threshold parameter. Our penalized estimators not only select covariates but also discriminate between a model with homogenous sparsity and a model with a change point. As a result, it is not necessary to know or pretest whether the change point is present, or where it occurs. Our estimator of the change point achieves an oracle property in the sense that its asymptotic distribution is the same as if the unknown active sets of regression coefficients were known. Importantly, we establish this oracle property without a perfect covariate selection, thereby avoiding the need for the minimum level condition on the signals of active covariates. Dealing with high-dimensional quantile regression with an unknown change point calls for a new proof technique since the quantile loss function is nonsmooth and furthermore the corresponding objective function is nonconvex with respect to the change point. The technique developed in this article is applicable to a general M-estimation framework with a change point, which may be of independent interest. The proposed methods are then illustrated via Monte Carlo experiments and an application to tipping in the dynamics of racial segregation. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

–To enhance the accuracy and reliability of fault-location estimates, an optimal fault-location estimator for power distribution systems with distributed generations is proposed in this article. Voltage and current measurements recorded at certain location/locations, such as power generation sites, are employed to estimate the fault location. The proposed method is able to make the most of available measurements, which may be from one location or multiple locations. Based on optimal estimation theory, the method is able to estimate the fault location, fault resistances, and true value of measurements. A chi-squared test is adopted to detect and identify possible bad measurements for improved estimation results. Evaluation studies based on a sample power distribution system have been carried out. Evaluation studies have demonstrated that the proposed method is effective for obtaining accurate fault-location estimates, as well as detecting and identifying possible bad measurements. [ABSTRACT FROM PUBLISHER]

Power distribution systems are desired to operate at their optimal control settings. These settings typically mean operation at low energy consumption and minimized distribution losses. Renewable energy resources can be very important for efficient operation of the distribution systems. However, when the number of renewables in the distribution system increases, the complexity of the control also increases. Intermittent renewable resources, particularly wind and solar, can cause significant fluctuations in distribution feeder voltages. This article presents a dual-layer control approach for finding the optimal feeder control settings and maintaining the feeder voltages within specified limits between the optimization intervals. The load-tap changer transformers, voltage regulator, capacitor banks, and smart inverters participate in the global control, while the smart inverters deal with the fast changing transients at the local control level. Thus, this control scheme will take full advantage of power-electronics-based smart inverters to reduce or eliminate fast transients, and also reduce the wear and tear of mechanical controllers. Evaluation studies are performed based on the IEEE 37 node radial test feeder under varying load and generation conditions. The results demonstrate that the proposed approach is promising for voltage and VAR control of distribution feeders with intermittent resources. [ABSTRACT FROM AUTHOR]

Most of the fault-location methods developed in the past employed measurements obtained from a limited number of meters installed in a power system. Optimal meter placement in power systems is to make the best use of a limited number of meters available to keep the entire network observable. This article presents the fault-location observability analysis for distribution systems and proposes a novel optimal meter placement algorithm to keep the system observable in terms of fault-location determination. First, the observability of fault location in power systems is defined. Then analysis of the whole system is performed to determine the fewest number of meters needed and the best locations to place those meters to achieve fault-location observability. Case studies based on a 16-bus distribution system have been carried out to illustrate the proposed algorithms. [ABSTRACT FROM AUTHOR]

We developed and psychometrically tested four scales for measuring the perceptions of parental smokers and family members’ influences on smoking behavior in the presence of children in Taiwan. Data were collected from 309 parental smokers with school-aged children. The results of factor analysis revealed two to three factors within each scale, and the reliability was between 0.63 and 0.91, based on Cronbach’s alpha. Our findings provide preliminary support for the reliability and validity of the scales. The collective application of the scales is comprehensive that may constitute a feasible approach for preventing parental smoking. [ABSTRACT FROM PUBLISHER]

Thanks to the various benefits promised by the smart grid, many utilities are considering deployment of smart grid technologies. For such cross-organizational projects to be successful, a concerted effort is needed, requiring a careful roadmap to be developed. However, there is a lack of methodical process in the current literature for describing the development of smart grid deployment roadmaps. This article presents the results of a recently completed project aimed at developing a comprehensive smart grid roadmap for the state of Kentucky, including the methods and processes utilized and the achieved roadmap plan. The project results may benefit roadmap development and smart grid deployment efforts in other states. [ABSTRACT FROM PUBLISHER]

Let {Vn, n ≥ 1} be a sequence of random elements in a real separable Banach space and suppose that {Vn,n ≥ 1} is stochastically dominated by a random element V. Let {an, n ≥ 1} and {bn, n ≥ 1} be real sequences with 0 < bn ↑ ∞. Conditions are provided under which {anVn, n ≥ 1} obeys the general strong law of large numbersalmost surely irrespective of the joint distributions of the {Vn, n ≥ 1}. No geometric conditions are imposed on the underlying Banach space. Examples are provided which illustrate, compare, or demonstrate the sharpness of the results. [ABSTRACT FROM PUBLISHER]

This study is designed to evaluate the relationship between endometrial thickness and clinical/biochemical parameters in women with chronic anovulation. One hundred and twenty women with ovulatory dysfunction were prospective included, endometrial thickness and endocrine and metabolic parameters were measured. The interval between the examination day and the day of the most recent menstrual bleeding (the anovulatory interval) for the studied subject was an average of 145 ± 186 days. The endometrial thickness averaged 7.1 ± 3.2 mm. Correlation analyses revealed that the endometrial thickness was positively correlated with body mass index but was not correlated with age, serum androgens, or estradiol (E2) levels. We further classified the subjects into two groups based on endometrial thickness: Group A, endometrial thickness <7 mm and Group B, endometrial thickness ≥7 mm. The anovulatory interval, follicle-stimulating hormone, luteinizing hormone, E2 and androgen levels were not significantly different between Groups A and B. Group B had higher body weight and more risk for metabolic syndrome. We concluded that endometrial thickness in women with ovulatory dysfunction is positively correlated with body weight status but is not correlated with serum androgens or E2 levels. [ABSTRACT FROM AUTHOR]

This article presents novel fault-location algorithms for distribution systems by utilizing voltage and current measurements at the local substation. The methods extend from previously published algorithms by explicitly modeling feeder shunt capacitances so that the methods will be applicable to distribution feeders with significant capacitances, such as underground cables. The bus impedance matrix technique is harnessed to develop the relationship between the substation voltage and current and the fault location and fault resistances, based on which the fault location can be derived. To accommodate inherent unbalances in distribution systems, the methods are developed in the phase domain instead of the symmetrical component domain. The distribution network parameters and topology are assumed to be known for constructing the bus impedance matrix. Simulation studies have demonstrated that the methods can achieve very accurate results. [ABSTRACT FROM AUTHOR]

In this article, we consider the quasi-likelihood equation for generalized linear models (GLMs). Under some mild conditions, including the convergent system which is defined by Lai et al. (1979), we obtain the asymptotic existence of the solution to the above equation and show that , where β0 is the true value of parameter β and denotes the smallest (largest) eigenvalue of satisfying for given δ > 1. We also present the asymptotic normality of for univariate GLMs, based on which “studentized” large sample confidence intervals for β0 are constructed. Simulation results and related remarks are given. [ABSTRACT FROM AUTHOR]

This article describes a novel and accurate algorithm to determine the fault location on power transmission lines without requiring line parameters. Voltage and current measurements at the two ends of the transmission line during the fault are utilized for fault location, and no pre-fault data are needed. In the past, a two-terminal method has been proposed based on a simplified transmission line model with no shunt capacitances. This article presents a new and accurate method considering line shunt capacitances for unbalanced faults. In deriving the unknown fault location, the line parameters, including series impedance and shunt capacitance, are treated as unknown variables as well. Approaches based on both synchronized and unsynchronized measurements are described. Since there is not enough information in three-phase balanced fault cases, shunt capacitances are not considered for balanced faults; however, the method for balanced faults still proves to be quite accurate. The chief merit of the algorithm is that only voltage and current measurements during the fault are required, and there is no need to worry about line parameters in order to pinpoint the fault location. Evaluation studies based on simulated data have indicated that the new approaches yield quite accurate results. [ABSTRACT FROM AUTHOR]

Fishery products are one essential component of Taiwanese dietary consumption; however, a variety of sales channels of fishery products has rendered effective marketing a task of challenge. With considerations of the marketing characteristics for two types of market in Taiwan, i.e,. supermarkets and farmers' markets, this research drew up marketing strategies based on the 40 Principles of Invention according to the theory of inventive problem solving. Consumer behaviors in the different markets were analyzed in order to form alternatives of marketing for fishery products. Recommendations for supermarkets are (1) to understand consumers' needs through surveys; (2) selling supplementary products at the same location; (3) collecting and responding consumers' feedback. Three marketing strategies for farmers' market are suggested as: (1) implementing a reform of the products; (2) chatting with consumers; (3) providing information about the products. [ABSTRACT FROM AUTHOR]

This article presents a transmission line fault location algorithm based on distributed parameter line model by utilizing unsynchronized voltage and current measurements from two terminals of the line. The new solution fully considers the impacts of the shunt capacitance of the line and is virtually independent of fault resistance and source impedance. Evaluation studies based on simulation studies for verifying the accuracy of the algorithm are reported, and quite promising results have been achieved. [ABSTRACT FROM AUTHOR]

Diverse transmission line fault location methods have been proposed utilizing voltages and currents as inputs. This article develops several algorithms utilizing only the voltages, dispensing with current transformers and thus eliminating the errors caused by saturation of current transformers. The algorithms are applicable to line to ground faults, line to line faults, and line to line to ground faults. The algorithms utilize unsynchronized fault voltage measurements from two ends of a line and do not require pre-fault data. Shunt capacitances of the line are fully considered. Encouraging results have been obtained by simulation studies. [ABSTRACT FROM AUTHOR]

Fault-generated high-frequency noise has been proven to be effective for faulted phase selection. A combined method using HF noise, fast Fourier transform (FFT), and neural networks (NN) for phase selection has been proposed previously; however, FFT and NN have some implicit disadvantages. This paper describes a HF noise based method for phase selection using wavelets based feature extraction. It is shown that the features extracted by wavelets transform (WT) have a more distinctive property than those extracted by FFT due to the good time and frequency localization characteristics of WT. As a result, the proposed method dispenses with the neural networks and hence is more reliable and simpler than the previous FFT-based method. Extensive simulation studies have been made to verify that the proposed approach is very powerful and apropos to phase selection. [ABSTRACT FROM AUTHOR]

Transition-metal-substituted polyoxometalates have attracted attention due to their remarkable physicochemical properties and applications in many research areas. Two new multi-manganese-substituted silicotungstates, tetramer [{Mn3Cl(OH)3(SiO4)}4(SiW9O34)4]36- (1) and banana-shaped [((MnOH2)0.5Mn2SiW9O34)2(SiW6O26)]22- (2), were prepared under hydrothermal conditions and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, etc. Compound 1 comprises four {SiW9O34} fragments, one {Mn3Cl(OH)3}4 cluster and four {SiO4} groups; it can form a 1 D-chain by connecting [{Mn3Cl(OH)3(SiO4)}4(SiW9O34)4]36− cluster units with Na+ cations. Banana-shaped 2 consists of two {(MnIIOH2)0.5MnIII2SiW9O34} fragments connected by a hexavacant {SiW6O26} motif, and it displays an interesting 3-D architecture by bridging banana-shaped [((MnIIOH2)0.5MnIII2SiW9O34)2(SiW6O26)]18- polyanion with four-member Na-cluster. 3-D packing of 2 along the c-axis creates two types of elliptical channels with sizes of 7.86 Å × 13.35 Å and 16.03 Å × 25.28 Å, respectively. Also, while coupling with [Ir(ppy)2(dtbbpy)]+ as photosensitizer and triethanolamine (TEOA) as sacrificial electron donor, both compounds show decent catalytic activity towards hydrogen production under visible LED light irradiation. [ABSTRACT FROM AUTHOR]

The traditional service restoration methods are experiencing a significant challenge because the performance of such methods is often dominated by very large processing time. Therefore, it is important to develop a fast and an accurate method to solve a complex non-linear optimization problem representing the service restoration problem in a distribution system. In this paper, due to a binary nature of the service restoration problem, the Binary Water Cycle Algorithm (BWCA) is proposed to reduce out-of-service loads and system losses considering operational constraints, the radial topology of the distribution systems, and the influence of the presence of distributed generations (DGs) on the service restoration problem. The proposed method is a modified form of the Water Cycle Algorithm (WCA) that is mainly used for discrete and continuous optimization problems. The effectiveness of the proposed method is validated by comparing with other well-known meta-heuristic algorithms using a modified IEEE 33-node radial distribution system. The simulation results demonstrate the robustness of this method to provide a precise decision with short convergence time for solving service restoration problems. [ABSTRACT FROM AUTHOR]

Distributed generation sources (DGs) are widely considered as important sources of power generation in distribution systems during the last few decades. Despite the substantial benefits of DGs, increasing the penetration level of the DGs can cause dramatic voltage magnitude fluctuations. Coordination of the use of dynamic reactive power sources such as photovoltaic (PV) inverters and voltage control equipment can mitigate rapid voltage magnitude fluctuations. A coordinated volt-var control method is proposed herein to achieve the optimal expected performance (e.g., system losses) while considering the spatial correlation among PV source powers and constraining the variability of voltage magnitudes throughout the distribution network within permissible ranges. The proposed strategy formulates chance constraints on the voltage magnitude and considers the uncertainty of PV power injections over the interval of interest to maintain voltage magnitudes within acceptable limits. The proposed method has been tested on the IEEE 123-node radial distribution system for validation. Moreover, the simulation results demonstrate that the proposed method can effectively mitigate the fast voltage magnitude deviations with an acceptable reduction in system losses in the presence of intermittent renewable resources. [ABSTRACT FROM AUTHOR]

There has not been a satisfactory solution to identifying and locating evolving faults on transmission lines until now. This paper presents an integrated detection and location approach for evolving faults based on transient traveling waves. Evolving faults include two sequential faults, resulting in the change of fault phase. The feature aerial mode of captured current traveling wave only reflects the feature of the second fault occurrence, and is used for analyzing the second fault. By combining traveling wave and transient energy features, fault phase selection can be implemented at two stages: the initial fault occurrence, and the short period before fault clearance. The evolving faults can be determined according to the consistency of the two-stage phase-selection results. Subsequently, the positions of the two successive faults can be precisely acquired by individually implementing the double-ended traveling wave fault location on the initial fault phase as well as the feature aerial mode currents, respectively. Digital simulation studies based on the simulation software PSCAD/EMTDC demonstrate that the proposed method is feasible and effective. [ABSTRACT FROM PUBLISHER]

The use of new psychoactive substances (NPSs) has markedly increased worldwide; thus, it is important to monitor NPS-related effects. The Taiwan Emergency Department Drug Abuse Surveillance (TEDAS) project aims to assess the patterns of recreational drug use in patients presenting to emergency departments (EDs) across the country. Here, we report the preliminary results of this project. This observational study included the collection and analysis of urine samples and assessment of the clinical presentation of patients from 79 EDs across Taiwan. Clinical features were recorded through a questionnaire filled by attending doctors or nurses who collected urine samples for clinical diagnosis. Urine samples were analyzed for 110 drugs and metabolites using electrospray ionization liquid chromatography-tandem mass spectrometry (LC-MS/MS). Between February and November 2019, a total of 2649 patients were enrolled for urine drug analysis. A total of 675 cases older than 12 years (males, n = 480) had NPS or other illicit drugs detected in their urine samples. Overall, 1271 counts of drugs, among which 717 (56.4%) were NPS. At least one NPS was detected in 340 patients (50.4%), and 292 cases were positive for multiple drugs. The most frequently detected drug was methamphetamine/amphetamine, followed by synthetic cathinones, ketamine and its two analogs, and opioids. The most common drug combination was cathinones plus ketamine and/or its analogs (n = 56). Younger patients (OR = 3.3, p≤.0001) and women (OR = 1.5, p =.01) were more likely to have NPS detected in their urine samples. NPS-positive cases frequently experienced chest pain (OR = 2.6, p =.03), tachycardia (OR = 2.6, p =.0002), and suicide attempt/non-suicidal self-harm (OR = 1.8, p =.004), whereas depressed consciousness (OR = 0.5, p =.001) was less frequent among NPS-positive cases than among other illicit drug-positive cases. The TEDAS project provides a nationwide epidemiological profile of recreational drug use in Taiwan. More than half of the recreational drugs were NPSs, which were comprehensively detected using LC-MS/MS. [ABSTRACT FROM AUTHOR]

5/6 Nephrectomy (PNx) on rat and mouse mimics renal failure after loss of kidney function in human, and it has been widely used in CKD researches. However, existing methods for PNx model construction present high mortality of animals after modeling due to hemorrhage and infection in or after surgery. Here, we report a novel and highly efficient PNx modeling method to simulate conventional 5/6 nephrectomy, which significantly reduced the mortality of animals and simplified the modeling procedures. In this novel modeling method, we directly ligated the upper and lower poles of left kidney after removal the right kidney 1 week later (l-PNx), which leads to necrosis of ligated upper and lower poles of the kidney and mimics the conventional 5/6 nephrectomy (c-PNx). After modeling 4 and 12 weeks, the serum creatinine, BUN and proteinuria levels were strongly increased in both c-PNx and l-PNx model. Importantly, compared with the c-PNx, l-PNx model present more severe renal fibrosis estimated by Masson staining, IHC and western blotting. The results showed that the protein levels of α-SMA were significantly increased in the kidney of c-PNx and l-PNx models, but more increase was found in l-PNx model. It is noteworthy that, compared with c-PNx model, the survival rate of l-PNx model was markedly increased. In summary, we established a novel and efficient 5/6 nephrectomy model, which can mimic conventional 5/6 nephrectomy to construct a renal fibrosis and renal failure mouse model, that is conducive to mechanism and treatment researches of CKD. [ABSTRACT FROM AUTHOR]