Radiation pattern of the isolated pulsar PSR B1828-11

Based on the free precession model of the isolated pulsar PSR B1828-11, Link & Epstein 2001) showed that the observed pulse durations require the radio beam to have a non-standard shape: the beam duration is larger for beam sweeps farthest from the dipole axis. In their analysis they assumed that the actual precession period is ~ 500 d. Recent theoretical studies suggested that the actual precession period might be ~ 1000 d as seen in observations (Rezania 2002, Wasserman 2002). In this paper, in a good agreement with the observed data (Stairs et al. 2000), we model the changes of the pulse shape in a precession cycle with period ~ 1000 d and find that the variation of the pulse duration follows from a {\it standard} beam pattern in each cycle.Comment: 9 pages, 3 figures, Accepted for publication in A&

The possible role of r-modes in post-glitch relaxation of Crab

The loss of angular momentum through gravitational radiation, driven by the excitation of r-modes, is considered in neutron stars having rotation frequencies smaller than the associated critical frequency. We find that for reasonable values of the initial amplitudes of such pulsation modes of the star, being excited at the event of a glitch in a pulsar, the total post-glitch losses correspond to a negligible fraction of the initial rise of the spin frequency in the case of Vela and the older pulsars. However, for the Crab pulsar the same effect would result, within a few months, in a decrease in its spin frequency by an amount larger than its glitch-induced frequency increase. This could provide an explanation for the peculiar behavior observed in the post-glitch relaxations of the Crab.Comment: 9 pages, 4 figures, RevTe

PENGARUH KONSERVATISME LABA, VOLUNTARY DISCLOSURE DAN KETEPATAN WAKTU (TIMELINESS) LAPORAN KEUANGAN TERHADAP EARNINGS RESPONSE COEFFICIENT (Suatu Studi pada Perusahaan Manufaktur yang Listing di Bursa Efek Indonesia Tahun 2010-2013)

ABSTRAK Penelitian ini bertujuan untuk memberikan gambaran bagaimana konservatisme laba, voluntay disclosure, ketepatan waktu (timeliness) laporan keuangan dan earnings response coefficient pada perusahaan manufaktur yang listing di Bursa Efek Indonesia (BEI) tahun 2010-2013 serta mengetahui pengaruh konservatisme laba, voluntay disclosure dan ketepatan waktu (timeliness) laporan keuangan terhadap earnings response coefficient. Metode penelitian yang digunakan adalah metode deskriptif verifikatif. Populasi dari penelitian ini yaitu sebanyak 142 perusahaan manufaktur yang listing di BEI tahun 2010-2013. Metode pemilihan sampel penelitian ini menggunakan match pair samples dengan total 40 perusahaan yang memenuhi kriteria. Analisis data dilakukan dengan menggunakan uji asumsi klasik dan pengujian hipotesis dengan regresi linear berganda. Berdasarkan hasil penelitian menunjukkan bahwa sebagian besar perusahaan manufaktur yang listing di BEI tahun 2010-2013 memiliki laba konservatif yaitu sebesar 87,5% dan mempunyai rata-rata untuk indeks voluntary disclosure sebesar 35,8% dengan ketepatan waktu (timeliness) laporan keuangan yaitu sebesar 118 perusahaan dari total 142 perusahaan menyampaikan laporan keuangan secara tepat waktu. Earnings response coefficient mempunyai rata-rata positif yaitu sebesar 0,062. Ini berarti bahwa setiap perubahan 1% return saham akan mengakibatkan perubahan laba sebesar 0,062%. Secara parsial konsevatisme laba, voluntary disclosure dan ketepatan waktu (timeliness) laporan keuangan berpengaruh terhadap earnings response coefficient. Secara simultan konservatisme laba, voluntary disclosure dan ketepatan waktu (timeliness) laporan keuangan berpengaruh signifikan terhadap earnings response coefficient yaitu sebesar 23,6%. Kata Kunci: konservatisme laba, voluntary disclosure, ketepatan waktu (timeliness) laporan keuangan, earnings response coefficien

System-based Integration of Electric Vehicles in an Electricity System

Die Förderung von alternativen Antriebstechnologien wie z. B. Elektrofahrzeugen, die in das Verkehrs- und Stromsystem integriert werden, muss auf effizienten und wirtschaftlich sinnvollen Umsetzungskonzepten basieren. Eine erfolgreiche Eingliederung von Elektrofahrzeugen in ein Stromsystem wird von geeigneten „Business Cases“ beeinflusst. Die Umsetzung der Mobilitätsbedürfnisse der Fahrzeugnutzer muss als Hauptbedingung jeder Zielfunktion definiert werden. Der Ansatz in diesem Beitrag basiert auf der systematischen Auswertung verschiedener Konzepte zum Auf- (Richtung des elektrischen Stroms vom Netz zum Fahrzeug) und Entladen (Richtung des elektrischen Stroms vom Fahrzeug zum Netz) von Elektrofahrzeugen, die wie folgt unterteilt sind: unkontrollierte, kontrollierte und intelligente Auf- und Entladestrategien. Die betrachteten Konzepte gehören alle zu den kontrollierten Strategien. In allen untersuchten Anwendungen konnten für das Entladen von Batterien (im Fall von LiFePO4-Batterien) keine zufriedenstellenden Ergebnisse erzielt werden. Somit ist eine wirtschaftliche Umsetzung solcher Konzepte nicht möglich. Die Hauptgründe hierfür sind der hohe Kapazitätsverlust der Batterie durch das Entladen und die damit verbundenen Degradationskosten. Daher reichen die voraussichtlichen Einnahmen, die mit den Entladungskonzepten erzielt werden können, nicht aus, um die Kosten für Wechselrichter und die erforderlichen Investitionen für Kommunikations- und Kontrollinfrastruktur zu decken. Was die wirtschaftliche Analyse und den Einfluss der hohen Durchdringungsrate von Elektrofahrzeugen auf Niederspannungsnetze angeht, so ist eine systemrelevante Integration von Elektrofahrzeugen in zwei verschiedene Implementierungsstufen unterteilt.The support of alternative propulsion technologies like electric vehicles being integrated into transport and electricity systems must be based on efficient and economically reasonable implementation concepts. A successful integration of electric vehicles into an electricity system is affected by adequate business cases. The realisation of the mobility needs of vehicle users must be defined as a main constraint for each target function. The approach within this paper is based on systematic analysis of various charging (direction of electric current from grid to vehicle) and discharging (direction of electric current from vehicle to grid) concepts for electric vehicles, which are subdivided into: uncontrolled, controlled and intelligent charging and discharging strategies. The considered concepts are allocated to the controlled one. In all analysed applications, the discharging of batteries (in case of LiFePO4 batteries) cannot achieve sufficient revenues. This makes an economical realisation of such concepts unfeasible. The main reasons are high battery capacity losses due to discharging and the associated battery degradation costs. Therefore, the calculated revenues of discharging concepts are not able to cover inverter costs and the investments needed for the communication and control infrastructure. In terms of economic analysis and the impact of a high penetration level of electric vehicles on low voltage grids, a system-relevant integration of EVs is subdivided into two different implementation stages

Effect of Soil Moisture Evaporation Rate on Dynamic Measurement of Water Retention Curve with High-Capacity Tensiometer

This paper investigates the effect of soil moisture evaporation rate on the soil water retention curve (SWRC) of clays obtained using high-capacity tensiometer (HCT) technique and following the continuous drying (dynamic) method. SWRC measurements, with and without soil moisture evaporation rate control, were carried out on reconstituted London clay specimens using 12 performance-improved HCTs recently developed at the University of Warwick. Furthermore, the HCTs’ performance in terms of the maximum attainable suction (sₘₐₓ) and maximum measurement duration (tₘₐₓ) was evaluated. Moreover, the suitability of a curve fitting-based model, available in the literature, for attaining the entire retention curve (beyond the capacity of HCTs) was evaluated. The SWRCs for tests with controlled evaporation rate were found to be generally exhibiting higher suctions at a given water content, hence inducing air-entry values that were on average 16% higher than those obtained from tests without evaporation rate control. It was also found that for suctions beyond 2 MPa, the curve fitting-based model predictions of data obtained from tests with controlled evaporation rate exhibit significantly lower suctions at a given water content than those without evaporation rate control, suggesting that such curve fitting correlations should be used with caution

Studi Komparatif Antara Penambahan Efective Microorganism-4 (EM-4) dan Limbah Lumpur Aktif Sebagai Stimulator dalam Pembuatan Kompos di RSUP Dr. Sardjito Yogyakarta

The efforts to handling amount of litter is to process the litter become compost. EM-4 and activated sludge waste of Dr. Sardjito General Hospital are stimulators useful to accelerate composting process. Purpose of this research was to know the difference of time, pH, temperature and NPK content of compost with addition of EM-4 and activated sludge waste. Method of this research was experiment with posttest only with control group design. Population of this research were all leaf litters taken from park of Dr. Sardjito General Hospital everyday weighting of 40 kg litters, sample of the research were 27 kg litters 3 kg of the litters were assigned into every control group, 3 kg are assigned into EM-4 treatment and 3 kg are assigned into active sludge waste and every experiment was repeated 3 times. Statistical test used in this research is One-way ANOVA assisted by SPSS 17 software. Result of the research indicated that there were differences of time and temperature but there was no difference pH between compost added with EM- 4 and one added with activated sludge waste and whereas there was a significant difference NPK content between EM-4-added compost and activated sludge waste-added compost. Results of laboratory test on EM-4-added compost indicated average content of N (1.17%), P (0.127%), and K (0.79%). Whereas on activated sludge waste-added compost contained average content of N (2.28%), P (0.217%) and K (1.993%)

Geological and Geotechnical Characteristics of London Clay from the Isle of Sheppey

The paper describes a series of experimental testing on natural stiff London clay samples retrieved from the New Hook Farm in the Isle of Sheppey, UK. The experimental program includes determination of macroscopic and microscopic properties, chemical compositions, Atterberg limits, permeability, and compressibility parameters in both intact and reconstituted states. The paper integrates the earlier studies, the new findings, and the commercial investigation results with the aim to extend the current knowledge of the geological and geotechnical characteristics of this stiff clay from the east of the London basin. Some comparisons are also made with shallow depth London clay from Heathrow Terminal 5 site