Fatty acid composition of oil in snow crab (Chionoecetes opilio) by gas chromatography/mass spectrometry

The hepatopancreatic fatty acid extract of the snow crab contains a high percentage (26%) of odd-carbon-numbered fatty acids and a substantial quantity (29%) of methyl-branched fatty acids, as indicated by gas chromatography/mass spectrometry (GC/MS) and gas liquid chromatography (GLC). A wide distribution in chain length of the fatty acids (C₁₀ to C₂₆) and in positional isomers of the linear monoenes are also indicated by GC/MS.     

Synthesis and thermal properties of poly(phenoxy trifluoroethoxy phosphazenes)

Copolymers were prepared by the reaction of poly(dichloro phosphazene), phenoxide, and trifluoro ethoxide in THF. Elastic copolymers having lower T_g than that of poly(trifluoroethoxy phosphazene) were formed when the ratio of phenoxide: trifluoro ethoxide was between 0.5:1.5 and 1.5:0.5.     

The mechanism of oxidative degradation of ABS resin. Part II. The mechanism of photooxidative degradation

The mechanism of oxidative degradation of ABS resin under ultraviolet irradiation, especially with respect to the wavelength dependencies of the photooxidative rate, has been examined by a spectroweather tester and infrared spectroscopy. The irradiation wave region was 290–800 mμ, and the region was divided into six parts. The changes in each part were examined by infrared spectroscopy. The absorption bands belonging to nitrile and phenyl groups showed no changes, but bands belonging to carbonyl and hydroxyl groups changed markedly, much as in the thermooxidative degradation described in a previous paper. There was a distinct gap between the third and fourth regions, which corresponded to 350 mμ. The graph of the normalized absorbance ratio and the logarithm of the wavelength gave a straight line, and it indicated that the rate of oxidation is proportional to the light intensity and the logarithm of the wavenumber.     

Provably Fast Training Algorithms for Support Vector Machines

Support Vector Machines are a family of algorithms for the analysis of data based on convex Quadratic Programming. We derive randomized algorithms for training SVMs, based on a variation of Random Sampling Techniques; these have been successfully used for similar problems. We formally prove an upper bound on the expected running time which is quasilinear with respect to the number of data points and polynomial with respect to the other parameters, i.e., the number of attributes and the inverse of a chosen soft margin parameter. [This is the combined journal version of the conference papers (Balcázar, J.L. et al. in Proceedings of 12th International Conference on Algorithmic Learning Theory (ALT’01), pp. 119–134, [2001]; Balcázar, J.L. et al. in Proceedings of First IEEE International Conference on Data Mining (ICDM’01), pp. 43–50, [2001]; and Balcázar, J.L. et al. in Proceedings of SIAM Workshop in Discrete Mathematics and Data Mining, pp. 19–29, [2002]).] The first and the fourth authors started this research while visiting the Centre de Recerca Matemàtica of the Institute of Catalan Studies in Barcelona. The first author was supported by IST Programme of the EU under contract number IST-1999-14186 (ALCOM-FT), Spanish Government TIC2004-07925-C03-02, and CIRIT 2001SGR-00252. The second author conducted this research while she was with Department of Mathematical and Computing Sciences, Tokyo Institue of Technology, and was supported by a Grant-in-Aid (C-13650444) from Japanese Goverment. The fourth author was supported in part by a Grant-in-Aid for Scientific Research on Priority Areas “Discovery Science” 1998–2000 from Japanese Goverment.     

Identification of activity stop locations in GPS trajectories by density-based clustering method combined with support vector machines

The identification of activity locations in continuous GPS trajectories is an essential preliminary step in obtaining person trip data and for activity-based transportation demand forecasting. In this research, a two-step methodology for identifying activity stop locations is proposed. In the first step, an improved density-based spatial clustering of applications with noise (DBSCAN) algorithm identifies stop points and moving points; then in the second step, the support vector machines (SVMs) method distinguishes activity stops from non-activity stops among the identified stop points. A time sequence constraint and a direction change constraint are applied as improvements to DBSCAN (yielding an improved algorithm known as C-DBSCAN). Then three major features are extracted for use in the SVMs method: stop duration, mean distance to the centroid of a cluster of points at a stop location, and the shorter of distances from current location to home and to the workplace. The proposed methodology was tested using GPS data collected from mobile phones in the Nagoya area of Japan. The C-DBSCAN algorithm achieves an accuracy of 90 % in identifying stop points in the first step, while the SVMs method is 96 % accurate in distinguishing the locations of activity stops from non-activity stops in the second step. Compared to other variants of DBSCAN used to identify activity locations from GPS trajectories, this two-step method is generally superior.

     

Impact of two types of partner,perceived or actual,in human–human and human–agent interaction

Participants engaged in the Prisoner’s dilemma game with a partner through a computer terminal. We define two types of partner: a perceived partner and an actual partner, and manipulated the two factors independently. A perceived partner means a partner with whom participants imagined themselves to be interacting; instruction given by an experimenter controls the image of the perceived partner. An actual partner can change its behavior. In one scenario participants actually interacted with a human partner, in another scenario their partner was either a mostly cooperating computer agent or a mostly defecting computer agent. Three experiments were performed. The result suggested that the participants’ selection behavior was largely influenced by the instruction given about the partner by the experimenter and not influenced by the partner’s actual behavior. The analysis of the participants’ impressions of the partner showed that the effect of instruction about the partner disappeared. Individual likeability for a partner was very influenced by the partner’s behavior; as the participants incurred more defect actions from the partner, individual likeability for the partner decreased. On the other hand, social likeability for a partner was not so influenced by the partner’s behavior, but rather related to the participants’ own behavior. The participants who made more defect actions rated their partner’s social likeability lower.     

Inhibition of deterioration of plastics by hydroaromatics

Based on our previous works concluding that the addition of hydrogen-donating hydroaromatics is effective in inhibiting the deterioration of hydrocarbons, heavy hydroaromatics from petroleum (HHAP) that were produced by hydrogenating highly aromatic heavy oil containing partly hydrogenated condensed aromatic rings were examined by the addition to high-density polyethylene (PE), isotactic polypropylene (PP), and poly(vinyl chloride) (PVC, MW: 1300) after confirming its prominent hydrogen-donating ability. The following results were obtained by the deterioration tests and melt-flow tests: (1) Clear inhibiting effects could be found on preservation of elongation and tensile strength by the addition of 0.1% and 0.5% of HHAP to PE. (2) Cross-linking of PE was restricted by the addition of HHAP. (3) Obvious effects could be found on preservation of elongation and tensile strength by the addition of 0.5% of HHAP to PP, but 0.1% of HHAP was not so effective. (4) Melt-flow rate of PP at 270°C supported the results of the deterioration tests at 120°C. (5) Color changes were remarkably improved by the addition of HHAP to PVC (at 160°C, 140 min). From these results, hydrogen donation from hydroaromatics can be considered effective in inhibiting the deterioration of PE, PP, and PVC.     

Preparation of Grain-Oriented Sr0.5Ba0.5Nb2O6 Ferroelectric Ceramics by Magnetic Alignment

The properties of polycrystalline ceramics are strongly influenced by their crystallographic texture. In this study, highly grain-oriented tungsten bronze structure ferroelectric ceramics, Sr_0.5Ba_0.5Nb₂O₆, were successfully fabricated by magnetic alignment and gelcasting techniques using only the conventional solid-state-synthesized starting powder. Spherical Sr_0.5Ba_0.5Nb₂O₆ particles were aligned according to their anisotropic magnetic property in 40 vol% slurry in a 10 T magnetic field, and then in situ locked by polymerization via a gelcasting technique for 30 min. A 〈00 l 〉-axis orientation perpendicular to the magnetic field direction ( B ) was obviously observed in the green compact and sintered sample. The sintered Sr_0.5Ba_0.5Nb₂O₆ sample contained equiaxial grains and reached 98% theoretical density. Compared with the sample with randomly oriented grains, the magnetically aligned sample showed an enhanced with dielectric constant in the ⊥ B direction (1100 versus 750 at room temperature and 4300 versus 2800 at Curie temperature). This new method is readily applicable to other ceramics with tungsten bronze structure, and is expected to facilitate mass preparation of large and dense grain-oriented ceramic materials.     

Occurrence of Dielectric 1:1:4 Compound in the Ternary System BaO—Ln2O3—TiO2 (Ln = La, Nd, and Sm): II, Reexamination of Formation of Isostructural Ternary Compounds in Identical Systems

To establish the correct composition of a ternary compound having higher TiO₂ content in the BaO—Nd₂O₃—TiO₂ system, the phase change of samples with variable controlled compositions, which were prepared by a modified coprecipitation method, was examined by X-ray diffractometry and Raman spectroscopy. Identification of the phases present in the calcined samples and microstructural evidence for the fired product from electron microprobe analysis clearly indicated that the ternary compound having the composition 1:1:4 occurs in the present system. X-ray powder diffraction data of the isostructural 1:1:4 and 1:1:3 compounds in each identical ternary system (Ln = La, Nd, and Sm) were refined and indexed. Partial subsolidus phase relations consisting of different composition triangles were also proposed for the present ternary systems.