Non-preemptive Scheduling in a Smart Grid Model and its Implications on Machine Minimization

We study a scheduling problem arising in demand response management in smart grid. Consumers send in power requests with a flexible feasible time interval during which their requests can be served. The grid controller, upon receiving power requests, schedules each request within the specified interval. The electricity cost is measured by a convex function of the load in each timeslot. The objective is to schedule all requests with the minimum total electricity cost. Previous work has studied cases where jobs have unit power requirement and unit duration. We extend the study to arbitrary power requirement and duration, which has been shown to be NP-hard. We give the first online algorithm for the general problem, and prove that the problem is fixed parameter tractable. We also show that the online algorithm is asymptotically optimal when the objective is to minimize the peak load. In addition, we observe that the classical non-preemptive machine minimization problem is a special case of the smart grid problem with min-peak objective, and show that we can solve the non-preemptive machine minimization problem asymptotically optimally

The factors affecting of digital mobile e-learning on development in senior high schools

Abstract. The traditional data envelopment analysis (DEA) model ignores the cooperative relationship among decision-making units (DMUs), so it is difficult to evaluate the DMUs efficiency reasonably. In this study, we use a cross-efficiency and bootstrap truncated regression (BTR) model to analyze the determining factors of digital mobile e-learning. The empirical results of this research indicate the following results: (1) Importing digital mobile e-learning can really enhance the efficiency of school management. (2) The school size, tablet PC numbers, total equipment expenses associated with tablet PC and school location are important determinants for affecting the efficiency of school management. Owing to the government is full implementation of the new learns model, that is, to be where the students able to experience the authentic joy of new learning model and attract students join. The result of the study suggested that in order to increase the school’s cross-efficiency model efficiency. The first assist the school in upgrading the Wi-Fi technology and network equipment. In general, the school adds to the Wi-Fi technology and network equipment. That would enlarge the school network and as to attract more school will adopt the new learning. It is where the students able to experience the authentic joy of new learning model and attract students join. Thus, the schools will increase school size. However, it should be noted that total equipment expenses associated with tablet PC have the negative influence on school management efficiency due to the increasing costs for furnishing the related internet and network equipment or device to facilitate for teaching and learning among teachers and students by digital mobile e-learning. The results of this research can also be the reference for educational authorities when formulating policies and regulations for promoting digital mobile e-learning in high school in Taiwan.Keywords. Operating efficiency, Digital mobile e-Learning, Data envelopment analysis (DEA), Truncated bootstrapped regression (TBR), Cross efficiency model.JEL. I21, I25, I28

Upgrading school efficiencies and learning interests through innovative teaching of digital mobile e-learning

Abstract. Assessing the digital mobile e-learning whether to affect school efficiency is an important yet complex issue. Consequently, this study goal of this research is to evaluate the innovative teaching to affect school efficiency (total efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) estimated by the data envelopment analysis (DEA) through using digital mobile e-learning of high school in Taiwan. Additionally, the Tobit regression model (TRM) is employed to discuss whether the other determinants affect using digital mobile e-learning of school efficiency. The findings can briefly be concluded as follows. The empirical results of this research indicate the following results: (1) Importing digital mobile e-learning can really enhance the efficiency of school management. (2) technical Efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) in the TRM analysis, it also indicates that school size, teacher-student ratio, school high-vocational attribute, especially the numbers of technical teachers in teaching or consulting about digital mobile e-learning knowledge and numbers of Tablet PC (the proxy for digital mobile e-learning) an important role in affecting these three efficiency of school management. Besides, the results show of total equipment expenses associated with tablet PC has a small negative influence on school management efficiency. Due to increasing costs for network equipment small effects on teaching and learning among teachers and students. The results of this research can also be the reference for educational authorities when formulating policies and regulations for promoting digital mobile e-learning.Keywords. Technical efficiency, Pure technical efficiency, Scale efficiency, Digital mobile e-Learning, Data envelopment analysis (DEA), Tobit regression model (TRM),Vocational and senior high school.JEL. I21, I25, I28

Effect of SnO2 addition on the dielectric properties of Ba2Ti9O20 ceramics in the high frequency regime

[[abstract]]The effect of SnO2 addition on the high-frequency dielectric properties of Ba2Ti9O20 ceramics has been investigated using terahertz time-domain spectroscopy, far-infrared (FIR) reflectivity, and Raman-scattering measurements. The dielectric constants determined from the terahertz and FIR spectra are smaller than that taken in the microwave frequency region. In contrast, the increase of the dielectric loss with increasing frequency is due to some resonance modes above 1 THz. Importantly, our data clearly show that the SnO2 (2.4 mole %) addition degraded the dielectric properties of Ba2Ti9O20 ceramics, which is ascribed to the deterioration on the coherency of lattice vibrational characteristics for these materials.[[booktype]]紙本[[booktype]]電子

Implications on η\eta-η′\eta'-glueball mixing from Bd/s→J/Ψη(′)B_{d/s} \to J/\Psi \eta^{(')} Decays

We point out that the recent Belle measurements of the $B_{d/s} \to J/\Psi \eta^{(')}$ decays imply large pseudoscalar glueball contents in the $\eta^{(\prime)}$ meson. These decays are studied in the perturbative QCD (PQCD) approach, considering the $\eta$-$\eta'$-$G$ mixing, where $G$ represents the pseudoscalar glueball. It is shown that the PQCD predictions for the $B_{d/s} \to J/\Psi \eta^{(')}$ branching ratios agree well with the data for the mixing angle $\phi_G\approx 30^\circ$ between the flavor-singlet state and the pure pseudoscalar glueball. Extending the formalism to the $\eta$-$\eta'$-$G$-$\eta_c$ tetramixing, the abnormally large observed $B_d\to K\eta'$ branching ratios are also explained. The proposed mixing formalism is applicable to other heavy meson decays into $\eta^{(\prime)}$ mesons, and could be tested by future LHCb and Super-$B$ factory data.Comment: Improved version, references added, 7 pages, 1 figur

Search for serendipitous TNO occultation in X-rays

To study the population properties of small, remote objects beyond Neptune's orbit in the outer solar system, of kilometer size or smaller, serendipitous occultation search is so far the only way. For hectometer-sized Trans-Neptunian Objects (TNOs), optical shadows actually disappear because of diffraction. Observations at shorter wave lengths are needed. Here we report the effort of TNO occultation search in X-rays using RXTE/PCA data of Sco X-1 taken from June 2007 to October 2011. No definite TNO occultation events were found in the 334 ks data. We investigate the detection efficiency dependence on the TNO size to better define the sensible size range of our approach and suggest upper limits to the TNO size distribution in the size range from 30 m to 300 m. A list of X-ray sources suitable for future larger facilities to observe is proposed.Comment: Accepted to publish in MNRA