Parameter estimation of the vibrational model for the SCOLE experimental facility

The objective of this study is to experimentally determine an empirical model of the vibrational dynamics of the Spacecraft COntrol Laboratory Experiment (SCOLE) facility. The first two flexible modes of this test article are identified using a linear least-square identification procedure and the data utilized for this procedure are obtained by exciting the structure from a quiescent state with torque wheels. The time history data of rate gyro sensors and accelerometers due to excitation and after excitation in terms of free-decay are used in the parameter estimation of the vibrational model. The free-decay portion of the data is analyzed using the Discrete Fourier transform to determine the optimal model order to use in modelling the response. Linear least-square analysis is then used to select the parameters that best fit the output of an Autoregressive (AR) model to the data. The control effectiveness of the torque wheels is then determined using the excitation portion of the test data, again using linear least squares

You can’t burn the house down because of one bedbug: a qualitative study of changing gender norms in the prevention of violence against women and girls in an urban informal settlement in India [version 1; peer review: 1 approved, 1 approved with reservations]

Background: The contribution of structural inequalities and societal legitimisation to violence against women, which 30% of women in India survived in the last year, is widely accepted. There is a consensus that interventions should aim to change gender norms, particularly through community mobilisation. How this should be done is less clear. Methods: We did a qualitative study in a large informal settlement in Mumbai, an environment in which 41% of the population live. After reviewing the anonymised records of consultations with 1653 survivors of violence, we conducted 5 focus group discussions and 13 individual interviews with 71 women and men representing a range of age groups and communities. We based the interviews on fictitious biographical vignettes to elicit responses and develop an understanding of social norms. We hypothesised that, in trying to change norms, we might exploit the disjunction between descriptive norms (beliefs about what others actually do) and injunctive norms (beliefs about what others think one ought to do), focusing program activities on evidence that descriptive norms are changing. Results: We found that descriptive and injunctive norms were relatively similar with regard to femininity, masculinity, the need for marriage and childbearing, resistance to separation and divorce, and disapproval of friendships between women and men. Some constraints on women’s dress and mobility were relaxing, but there were more substantial differences between descriptive and injunctive norms around women’s education, control of income and finances, and premarital sexual relationships. Conclusions: Programmatically, we hope to exploit these areas of mismatch in the context of injunctive norms generally inimical to violence against women. We propose that an under-appreciated strategy is expansion of the reference group: induction of relatively isolated women and men into broader social groups whose descriptive and injunctive norms do not tolerate violence

You can't burn the house down because of one bedbug: a qualitative study of changing gender norms in the prevention of violence against women and girls in an urban informal settlement in India

Background: The contribution of structural inequalities and societal legitimisation to violence against women, which 30% of women in India survive each year, is widely accepted. There is a consensus that interventions should aim to change gender norms, particularly through community mobilisation. How this should be done is less clear. Methods: We did a qualitative study in a large informal settlement in Mumbai, an environment that characterises 41% of households. After reviewing the anonymised records of consultations with 1653 survivors of violence, we conducted 5 focus group discussions and 13 individual interviews with 71 women and men representing a range of age groups and communities. We based the interviews on fictitious biographical vignettes to elicit responses and develop an understanding of social norms. We wondered whether, in trying to change norms, we might exploit the disjunction between descriptive norms (beliefs about what others actually do) and injunctive norms (beliefs about what others think one ought to do), focusing program activities on evidence that descriptive norms are changing. Results: We found that descriptive and injunctive norms were relatively similar with regard to femininity, masculinity, the need for marriage and childbearing, resistance to separation and divorce, and disapproval of friendships between women and men. Some constraints on women's dress and mobility were relaxing, but there were more substantial differences between descriptive and injunctive norms around women's education, control of income and finances, and premarital sexual relationships. Conclusions: Programmatically, we hope to exploit these areas of mismatch in the context of injunctive norms generally inimical to violence against women. We propose that an under-appreciated strategy is expansion of the reference group: induction of relatively isolated women and men into broader social groups whose descriptive and injunctive norms do not tolerate violence

Using Participatory Learning and Action in a Community-Based Intervention to Prevent Violence Against Women and Girls in Mumbai's Informal Settlements

For over 3 decades, participatory learning and action (PLA) techniques have been prominent in formative and evaluative studies in community-based development programs in the Global South. In this paper, we describe and discuss the use of PLA approaches at the beginning of a community-based program for prevention of violence against women and girls in Mumbai’s urban informal settlements. We adapted six PLA techniques as part of a formative community mobilization and rapid needs assessment exercise, addressing perceptions of violence prevalence, sources of household conflict, experiences of safety and mobility, access to services, preferences for service and support, and visualization of an ideal community free from violence. We describe the collaborative process of developing and implementing PLA techniques and discuss its relevance in generating contextual and grounded understandings of violence as well as in identifying factors which can potentially enable and constrain interventions

Simultaneous observations of ESF irregularities over Indian region using radar and GPS

In this paper, we present simultaneous observations of temporal and spatial variability of total electron content (TEC) and GPS amplitude scintillations on L1 frequency (1.575 GHz) during the time of equatorial spread F (ESF) while the MST radar (53 MHz) located at Gadanki (13.5° N, 79.2° E, Dip latitude 6.3° N), a low latitude station, made simultaneous observations. In particular, the latitudinal and longitudinal extent of TEC and L-band scintillations was studied in the Indian region for different types of ESF structures observed using the MST radar during the low solar activity period of 2004 and 2005. Simultaneous radar and GPS observations during severe ESF events in the pre-midnight hour reveal that significant GPS L band scintillations, depletions in TEC, and the double derivative of the TEC index (DROTI), which is a measure of fluctuations in TEC, obtained at low latitudes coincide with the appearance of radar echoes at Gadanki. As expected, when the irregularities reach higher altitudes as seen in the radar map during pre-midnight periods, strong scintillations on an L-band signal are observed at higher latitudes. Conversely, when radar echoes are confined to only lower altitudes, weak scintillations are found and their latitudinal extent is small. During magnetically quiet periods, we have recorded plume type radar echoes during a post-midnight period that is devoid of L-band scintillations. Using spectral slopes and cross-correlation index of the VHF scintillation observations, we suggest that these irregularities could be "dead" or "fossil" bubbles which are just drifting in from west. This scenario is consistent with the observations where suppression of pre-reversal enhancement (PRE) in the eastward electric field is indicated by ionosonde observations of the height of equatorial F layer and also occurrence of low spectral width in the radar observations relative to pre-midnight period. However, absence of L-band scintillations during post-midnight event, when radar observed plume like structures and scintillations were recorded on VHF band, raises questions about the process of evolution of the irregularities. A possible explanation is that whereas small scale (∼3 m) irregularities are generated through secondary waves that grow on the walls of km scale size irregularities, in this case evolution of the Rayleigh-Taylor instability itself did not extend to irregularities of scale sizes of a few hundred meters that produce scintillation on a L-band signal

A theory of change for community interventions to prevent domestic violence against women and girls in Mumbai, India [version 1; peer review: 2 approved with reservations]

Background: We describe the development of a theory of change for community mobilisation activities to prevent violence against women and girls. These activities are part of a broader program in urban India that works toward primary, secondary, and tertiary prevention of violence and includes crisis response and counselling and medical, police, and legal assistance. / Methods: The theory of change was developed in five phases, via expert workshops, use of primary data, recurrent team meetings, adjustment at further meetings and workshops, and a review of published theories. / Results: The theory summarises inputs for primary and secondary prevention, consequent changes (positive and negative), and outcomes. It is fully adapted to the program context, was designed through an extended consultative process, emphasises secondary prevention as a pathway to primary prevention, and integrates community activism with referral and counselling interventions. / Conclusions: The theory specifies testable causal pathways to impact and will be evaluated in a controlled trial

A Bayesian Analysis of the Correlations Among Sunspot Cycles

Sunspot numbers form a comprehensive, long-duration proxy of solar activity and have been used numerous times to empirically investigate the properties of the solar cycle. A number of correlations have been discovered over the 24 cycles for which observational records are available. Here we carry out a sophisticated statistical analysis of the sunspot record that reaffirms these correlations, and sets up an empirical predictive framework for future cycles. An advantage of our approach is that it allows for rigorous assessment of both the statistical significance of various cycle features and the uncertainty associated with predictions. We summarize the data into three sequential relations that estimate the amplitude, duration, and time of rise to maximum for any cycle, given the values from the previous cycle. We find that there is no indication of a persistence in predictive power beyond one cycle, and conclude that the dynamo does not retain memory beyond one cycle. Based on sunspot records up to October 2011, we obtain, for Cycle 24, an estimated maximum smoothed monthly sunspot number of 97 +- 15, to occur in January--February 2014 +- 6 months.Comment: Accepted for publication in Solar Physic

Power spectral characteristics of ESF irregularities during magnetically quiet and disturbed days

Amplitude scintillations on 251 MHz signal recorded by spaced receivers at Tirunelveli (8.7°N, 77.8°E, dip latitude 0.6°N) for eight months during 1995–2005 are utilized in present work. Power spectral analysis of weak scintillations (0.15≤S4≤0.5) is carried out and spectral index, m of ESF irregularities, is computed for quiet and disturbed days. Maximum cross-correlation, CI(x0,t_m), of intensity variations between two receivers is used to identify the fresh generation of EPBs resulted from magnetic activity. Increase in F-region height is seen prior to the generation of these fresh EPBs and associated ESF irregularities found to possess shallower power spectrum

Study of equinoctial asymmetry in the Equatorial Spread F (ESF) irregularities over Indian region using multi-instrument observations in the descending phase of solar cycle 23

In this paper, we present the results of a morphological study of Equatorial Spread F (ESF) irregularities over Indian region based mainly on observations of (1) amplitude scintillations on GPS L-band signal and Rate of TEC Index (ROTI) obtained using a network of GPS receivers and (2) amplitude scintillations on a VHF signal using spaced receivers at Tirunelveli, an equatorial station. Occurrence of both amplitude scintillations on the GPS L1 signal and occurrence of significant ROTI recorded at several stations has been investigated. The latitudinal extent of L-band scintillations shows that their strength is weak over the dip equator but stronger over Equatorial Ionization Anomaly (EIA) region, preferentially during vernal equinox. We find an equinoctial asymmetry in both the occurrence of scintillations and ROTI wherein their occurrence is greater in the vernal equinox than in the autumn equinox. Attempts have been made to understand the asymmetry in latitudinal extent using maximum cross-correlation (C<SUB>I</SUB>) of intensity fluctuations obtained from the VHF spaced receivers observations. The observations suggest that occurrence of C<SUB>I</SUB> less than 0.5 is more in the vernal equinox than in the autumn equinox suggesting that the maximum height of the Equatorial Plasma Bubbles (EPBs) during vernal equinox may be higher than that during autumn equinox. TIMED/GUVI retrieved peak electron density during the same period also indicates that background electron density is higher and more symmetric during vernal equinox than autumn equinox. Hence, our results suggest that background electron density may be playing a vital role in creating the equinoctial asymmetry