| Judul | Abstract | Halaman |
|---|
| A Cyclical Nurse Schedule Using Goal Programming | Scheduling is a very tedious task in organizations where duty is around the clock. Constructing timetable for nurses in hospital is one of the challenging jobs for the head nurse or nurse manager. It requires a lot of time to spend for generating a good and fair timetable. Thus, in this study, we propose a cyclical nurse scheduling model using a 0-1 goal programming that would help the head nurse or nurse manager to have less effort on building new schedules periodically. The proposed model satisfies the stated hospital’s policies and the nurses’ preferences. The result obtained from this model gives an optimal solution where all goals are achieved. The model also provides an unbiased way of scheduling the nurses and thus leads to an overall higher satisfaction and fairness to the nurses and the hospital management. | 151-164 |
| Magnetic and Electrical Properties of Leachate | Heavy metals content as well as magnetic and electrical properties of leachate from Sarimukti, West Java were studied in an attempt to seek correlation between heavy metals content and magnetic/electrical properties. Such correlation is expected to open the way for the use of magnetic/electrical properties as proxy indicators for the concentration of heavy metals in the leachate. The number of leachate samples studied is 21; 15 were taken spatially at depth of 1 m while the remaining 6 samples were taken vertically at a particular point. Measurement results showed that the heavy metals content in the leachate has a smaller concentration, except for Fe. The correlation between magnetic susceptibility and heavy metals content was found to be not so significant. The best correlation coefficient between magnetic susceptibility with heavy metals in leachate was found in Zn. Correlation between electrical conductivity and heavy metal is also not so significant, except for Zn and Cd. The use of magnetic properties as proxy indicator for heavy metals content in leachate is plausible provided that the magnetic susceptibility exceeds certain threshold value. Correlation between magnetic susceptibility, electrical conductivity and heavy metal content would be good if each quantity has a large value. | 165-178 |
| Effects of Glucose on the Reactive Black 5 (RB5) Decolorization by Two White Rot Basidiomycetes | The capacities of glucose in the decolorization process of an azo dye, Reactive Black 5 (RB5), by two white rot basidiomycetes, Pleurotus sp. F019 and Trametes sp. F054 were investigated. The results indicated that the dye degradation by the two fungi was extremely correlated with the presence of glucose in the culture and the process of fungi growth. Decolorization of 200 mg dye/l was increased from 62% and 69% to 100% within 20–25 h with the increase of glucose from 5 to 15 g/l, and the activity of manganese dependent peroxidase (MnP) increased by 2–9 fold in this case. Hydrogen peroxide of 0.55 mg/l and 0.43 mg/l were detected in 10 h in Pleurotus sp. F019 and Trametes sp. F054 cultures. | 179-186 |
| Will 3552 Don Quixote Escape from the Solar System? | Asteroid 1983 SA, well known as 3552 Don Quixote, is one of Near Earth Asteroids (NEAs) which is the most probable candidate for the cometary origin, or otherwise as Jupiter-Family-Comets (JFCs). The aim of this study is to investigate the possibility of 3552 Don Quixote to be ejected from the Solar System. This paper presents an orbital evolution of 100 hypothetical asteroids generated by cloning 3552 Don Quixote. Investigation of its orbital evolution is conducted by using the SWIFT subroutine package, where the gravitational perturbations of eight major planets in the Solar System are considered. Over very short time scales (~220 kyr) relative to the Solar System life time (~10 Gyr), the asteroid 3552 Don Quixote gave an example of chaotic motion that can cause asteroid to move outward and may be followed by escaping from the Solar System. Probability of ejection within the 220 kyr time scale is 50%. | 187-198 |
| Band Alignment and Optical Properties of (ZrO2)0.66(HfO2)0.34 Gate Dielectrics Thin Films on p-Si (100) | (ZrO2)0.66(HfO2)0.34 dielectric films on p-Si (100) were grown by atomic layer deposition method, for which the conduction band offsets, valence band offsets and band gaps were obtained by using X-ray photoelectron spectroscopy and reflection electron energy loss spectroscopy. The band gap, valence and conduction band offset values for (ZrO2)0.66(HfO2)0.34 dielectric thin film, grown on Si substrate were about 5.34, 2.35 and 1.87 eV respectively. This band alignment was similar to that of ZrO2. In addition, the dielectric function ɛ(k, ω), index of refraction n and the extinction coefficient k for the (ZrO2)0.66(HfO2)0.34 thin films were obtained from a quantitative analysis of REELS data by comparison to detailed dielectric response model calculations using the QUEELS-ɛ (k,ω)-REELS software package. These optical properties are similar with ZrO2 dielectric thin films. | 199-208 |
| Surfaces with Prescribed Nodes and Minimum Energy Integral of Fractional Order | This paper presents a method of finding a continuous, real-valued, function of two variables z = u(x, y) defined on the square S := [0,1]2 , which minimizes an energy integral of fractional order, subject to the condition u(0, y) = u(1, y) = u(x,0) = u(x,1) = 0 and u(xi ,yj)=c | 209-222 |
