Anonymization of Sensitive Quasi-Identifiers for l-diversity and t-closeness

A number of studies on privacy-preserving data mining have been proposed. Most of them assume that they can separate quasi-identifiers (QIDs) from sensitive attributes. For instance, they assume that address, job, and age are QIDs but are not sensitive attributes and that a disease name is a sensitive attribute but is not a QID. However, all of these attributes can have features that are both sensitive attributes and QIDs in practice. In this paper, we refer to these attributes as sensitive QIDs and we propose novel privacy models, namely, (l1, ..., lq)-diversity and (t1, ..., tq)-closeness, and a method that can treat sensitive QIDs. Our method is composed of two algorithms: an anonymization algorithm and a reconstruction algorithm. The anonymization algorithm, which is conducted by data holders, is simple but effective, whereas the reconstruction algorithm, which is conducted by data analyzers, can be conducted according to each data analyzer’s objective. Our proposed method was experimentally evaluated using real data sets

Part I. Meridian-Scanning Photometric System for Proton Auroras and Electron Auroras (Constitution of Proton Aurora and Electron Aurora Substorms) (AERONOMY)

A meridian scanning photometric system was designed for the simultaneous observation of the dynamic behavior of the proton and electron auroras with high time resolution. The hydrogen Balmer-beta (H_β) was selected as a typical emission line from proton auroras, whereas N_2+ 4278 Å, OI 5577 Å and OI 6300 Å emissions were selected for electron auroras. The H_β photometer has a so-called tilting filter to measure rapid space-time variations of faint proton auroras free from the contamination of strong electron auroras. The observations were carried out from March to October 1970 at Syowa Station (corrected geomagnetic lat. -66.7°, long. 72.5°) in Antarctica. From the records of the meridian scanning photometers, spatial distributitions of auroral luminosity along the geomagnetic meridian were displayed as a function of local time, and the iso-intensity contour lines were drawn. These space-time diagrams of auroral luminosity were shown to be very useful for the quantitative study of the dynamic behavior of auroras. Using auroral space-time diagrams, the constitution of the proton and electron aurora substorms was described in detail. During the growth phase of a magnetospheric substorm, the emission zone of the proton aurora moves equatorward with a speed of 100-200m/sec, accompanying the development of the asymmetric ring current and the positive H bay in the evening region. The equatorward movement and the growth of the asymmetric ring current were explained by an earthward movement of the ring current protons due to the intensification of the magnetospheric convection and the subsequent energization of protons through the betatron and Fermi acceleration processes. At the onset of the expansion phase, the quiet arcs suddenly brighten in the pre-midnight region, and the electron aurora bulge rapidly expands poleward and westward, whereas in the post-midnight region, the emission zone of proton auroras rapidly expands poleward and eastward with a large increase in luminosity. Proton auroras are absent in the leading edge of the expanding electron aurora bulge, while breakup-type electron auroras (arcs or bands) are not observed in the expanding proton aurora bulge. Therefore, it is suggested that there is a mechanism which accelerates electrons along the geomagnetic field lines from the magnetosphere down to the ionosphere in the pre-midnight region and protons in the postmidnight region. After the onset of the expansion phase, the luminosity of the proton aurora greatly increases, and simultaneously the emission zone expands equatorward in the evening region, accompanying the development of the asymmetric partial ring current and the positive bay. These features can be interpreted by means of the proton injection into the trapping region due to the magnetic collapse in the tail, and the subsequent westward and earthward drift. From the relationship between the movement of the proton auroras and the geomagnetic variation, it is suggested that the positive bay in the evening hours is induced by the eastward current concentrated along the emission zone of proton auroras. The enhancement of the ionospheric conductivity due to the precipitating protons required to excite the observed proton aurora luminosity is estimated to be sufficient for the concentration of the eastward current. A close relationship between the proton aurora and the IPDP event was also observed, indicating proton pitch-angle diffusion due to the ion cyclotron waves

Radiographic Prediction of the Results of Long-term Treatment with the Pavlik Harness for Developmental Dislocation of the Hip

In 1957, Pavlik introduced the Pavlik harness as a useful treatment for developmental dislocation of the hip (DDH), and subsequent studies have documented favorable outcomes among patients treated with this device. However, there are only a few articles reporting how early radiographic measurements can be used to determine the prognosis after treatment with the Pavlik harness. In this study, 217 hips from 192 patients whose DDH treatment with the Pavlik harness was initiated before they were 6 months old and whose follow-up lasted at least 14 years (rate, 63.8%) were analyzed using measurements from radiographs taken immediately before and after harness treatment, and at 1, 2, and 3 years of age. Severin's classification at the final follow-up was I or II in 71.9% and III or IV in 28.1% of the hips, respectively. Avascular necrosis of the femoral head (AVN) was seen in 10% of the hips. Stepwise multiple regression analysis was performed to retrospectively determine whether any radiographic factors were related to the final classification as Severin I/II or III/IV. Receiver opera-ting characteristic (ROC) curves were drawn for these factors, and a Wiberg OE angle (Point O was the middle point of the proximal metaphyseal border of the femur) of 2 degrees on the 3-year radiographs was found to be the most useful screening value for judging the acetabular development of DDH cases after treatment with a Pavlik harness, with a sensitivity of 71% a specificity of 93%, and a likelihood ratio of 10.1.</p

Legibility of Japanese characters in graphic floor signs for elderly people

For low-vision people and elderly people with decreased vision and cognitive function, the legibility of signs (character size, position, etc.) is an important issue. Graphic floor signs are considered more effective for low-vision people and elderly people than typical hanging signs because they are closer to pedestrians and can be larger in size. There is a growing number of improved graphic floor signs, but there are no guidelines for character sizes, colour scheme, and layout. Therefore, this study considers the character size ofgraphic floor signs that are legible for elderly people. In this study, we aimed to verify the legibility of characters installed on the floor. The test was conducted on 30 non-elderly and 30 elderly people, about Japanese Industrial Standards (JIS) S 0032 “Guidelines for the elderly and people with disabilities - Visual signs and displays -Estimation of minimum legible size for a Japanese single character”. Experiments on minimum legible sizes of characters and experiments on readability were conducted in that order. In the experiment on the minimum legible sizes of characters, we found that the minimum legible sizes of characters written on the vertical surface can be converted to the minimum size of legible characters written on the floor surface by multiplying with the coefficient of minimum legible characters on the floor surface by 2 to 3 times. In the experiment on readability, we found that the optimum character sizes are about 90 mm and 80 mm in height at a minimum for vertical and horizontal characters, respectively. These results showed that the optimum size of characters on graphic floor signs is about 90 mm.Peer Reviewe

Infrared Spectroscopy of CO Ro-vibrational Absorption Lines toward the Obscured AGN IRAS 08572+3915

We present high-resolution spectroscopy of gaseous CO absorption in the fundamental ro-vibrational band toward the heavily obscured active galactic nucleus (AGN) IRAS 08572+3915. We have detected absorption lines up to highly excited rotational levels (J<=17). The velocity profiles reveal three distinct components, the strongest and broadest (delta_v > 200 km s-1) of which is due to blueshifted (-160 km s-1) gas at a temperature of ~ 270 K absorbing at velocities as high as -400 km s-1. A much weaker but even warmer (~ 700 K) component, which is highly redshifted (+100 km s-1), is also detected, in addition to a cold (~ 20 K) component centered at the systemic velocity of the galaxy. On the assumption of local thermodynamic equilibrium, the column density of CO in the 270 K component is NCO ~ 4.5 x 10^18 cm-2, which in fully molecular gas corresponds to a H2 column density of NH2 ~ 2.5 x 10^22 cm-2. The thermal excitation of CO up to the observed high rotational levels requires a density greater than nc(H2) > 2 x 10^7 cm-3, implying that the thickness of the warm absorbing layer is extremely small (delta_d < 4 x 10-2 pc) even if it is highly clumped. The large column densities and high radial velocities associated with these warm components, as well as their temperatures, indicate that they originate in molecular clouds near the central engine of the AGN.Comment: 13 pages, 7 figures, accepted for publication in PASJ (Vol.65 No.1 2013/02/25

Photosynthetic physiology and primary productivity of phytoplankton in the Australian sector of the Southern Ocean

第2回極域科学シンポジウム　共通セッション「海氷圏の生物地球化学」 11月16日（水） 統計数理研究所 3階セミナー