Vol. 45 No. 3 (2013)

The effect of chlorine plasma treatment on electronic properties of GIZO grown on SiO2/Si by RF magnetron sputtering was investigated using X-ray photoelectron spectroscopy (XPS), reflection electron energy loss spectroscopy (REELS), and secondary ion mass spectroscopy (SIMS). SIMS depth profiles indicated that the concentration of InO and ZnO on the surface was decreased after Cl2 plasma treatment. REELS data showed that the band gap increased from 3.4 to 3.7 eV. XPS showed that Ind5/2 and Zn2p3/2 shifted to the higher binding energies by 0.5 eV and 0.3 eV, respectively. These phenomena were…

This paper discusses the cockpit crew rostering problem at Garuda Indonesia, taking into account a number of internal cockpit crew labor regulations. These internal labor regulations are in general more restrictive at Garuda Indonesia than at other airlines, so that modeling the cockpit crew rostering problem for Garuda Indonesia is challenging. We have derived mathematical expressions for the cockpit crew labor regulations and some technical matters. We model a non-linear integer programming for the rostering problem, using the average relative deviation of total flight time to the ideal…

It has been reported that Goniopora sp. coral originating from sea water can induce osteogenesis and regeneration of bone. However, biocompatibility and safety aspects of this material have not been reported yet. We have evaluated the mutagenicity of the raw material and the sterility of processed material of Indonesian coral Goniopora sp. as a potential candidate for osteogenic bone graft. In addition, heavy metals were also identified and determined. A mutagenicity test was conducted using the Ames test, while a sterility test was carried out based on the direct inoculation method. The…

For a simple, connected, undirected graph G(V, E) an open neighborhood coloring of the graph G is a mapping f: V (G) --> Z+ such that for each w in V(G), and for all u, v in N(w), f(u) is different from f(v). The maximum value of f(w), for all w in V (G) is called the span of the open neighborhood coloring f. The minimum value of span of f over all open neighborhood colorings f is called open neighborhood chromatic number of G, denoted by Xonc(G). In this paper we determine the open neighborhood chromatic number of prisms.

Tofu is a traditional food that can be found in several countries, such as Indonesia and Japan. Tofu is often made using the backslopping method, which brings the risk of pathogenic microorganism contamination and can lead to failure in production. Standardization of the production process is necessary in order to yield highly nutritious tofu that is safe to be consumed. In this research, standardization was investigated by variation of the inoculum percentages and ratios of Lactobacillus plantarum (a), Lactobacillus acidophilus (b), and Leuconostoc mesenteroides (c). The inoculum percentages…