Land subsidence over oilfields in the Yellow River Delta

Subsidence in river deltas is a complex process that has both natural and human causes. Increasing human activities like aquaculture and petroleum extraction are affecting the Yellow River delta, and one consequence is subsidence. The purpose of this study is to measure the surface displacements in the Yellow River delta region and to investigate the corresponding subsidence source. In this paper, the Stanford Method for Persistent Scatterers (StaMPS) package was employed to process Envisat ASAR images collected between 2007 and 2010. Consistent results between two descending tracks show subsidence with a mean rate up to 30 mm/yr in the radar line of sight direction in Gudao Town (oilfield), Gudong oilfield and Xianhe Town of the delta, each of which is within the delta, and also show that subsidence is not uniform across the delta. Field investigation shows a connection between areas of non-uniform subsidence and of petroleum extraction. In a 9 km2 area of the Gudao Oilfield, a poroelastic disk reservoir model is used to model the InSAR derived displacements. In general, good fits between InSAR observations and modeled displacements are seen. The subsidence observed in the vicinity of the oilfield is thus suggested to be caused by fluid extraction

ISBDD model for classification of hyperspectral remote sensing imagery

The diverse density (DD) algorithm was proposed to handle the problem of low classification accuracy when training samples contain interference such as mixed pixels. The DD algorithm can learn a feature vector from training bags, which comprise instances (pixels). However, the feature vector learned by the DD algorithm cannot always effectively represent one type of ground cover. To handle this problem, an instance space-based diverse density (ISBDD) model that employs a novel training strategy is proposed in this paper. In the ISBDD model, DD values of each pixel are computed instead of learning a feature vector, and as a result, the pixel can be classified according to its DD values. Airborne hyperspectral data collected by the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) sensor and the Push-broom Hyperspectral Imager (PHI) are applied to evaluate the performance of the proposed model. Results show that the overall classification accuracy of ISBDD model on the AVIRIS and PHI images is up to 97.65% and 89.02%, respectively, while the kappa coefficient is up to 0.97 and 0.88, respectively

Social Achievement goals and Academic Adjustment among College Students: Data from Pakistan

The study was conducted to investigate the social achievement goals and academic adjustment among college students in Pakistan. These variables were studied with gender and family system. The sample was consisting of 750 students from which 429 were boys and 321 were girls, age range was 15-20 years. Students form joint family system were 585 and 165 students were form nuclear family system. Student Adaption to College Questionnaire (SACQ) developed by Baker and Siryk (1984) and Social Achievement Goals Questionnaire (SAGQ) developed by Ryan and Shim (2006) were used to collect the data. After analyzing the questionnaire responses of the students, this research was highlighted the problems that the students may face while living in a joint family system. Results indicated that boys have more adaptation to college environment and have more social achievement goals as compared to girls. This research was also helping in knowing that the students from nuclear family system have more social achievement and adjustment to college environment as compared to students from joint family system

Respiratory Sinus Arrhythmia Acts as a Moderator of the Relationship Between Parental Marital Conflict and Adolescents’ Internalizing Problems

The present study examined the potential moderating role respiratory sinus arrhythmia (RSA) plays in the relationship between parental marital conflict and adolescents’ internalizing problems. To examine this issue, data were collected from 330 adolescents (13–14 years, 182 boys). The Chinese version of the Achenbach Youth Self-Report-2001 and the Chinese version of the Children’s Perception of Interparental Conflict were used to assess the adolescents’ internalizing problems and their perceptions of parental marital conflict. To obtain RSA data, electrocardiogram monitoring was performed on the adolescents at baseline and during a series of stress tasks (watching a film clip depicting marital conflict, a mental arithmetic task, and a speech task). The results indicated that baseline RSA and RSA reactivity to the film clip moderated the relationship between parental marital conflict and internalizing problems in early adolescents. The moderating effect of baseline RSA supported the BSCT hypothesis. Specifically, adolescents with low baseline RSA have both the highest and lowest levels of internalizing problems, depending on the level of marital conflict. In contrast, adolescents with high levels of baseline RSA have moderate levels in internalizing problems, regardless of the level of marital conflict they experience. Similarly, high marital conflict was related to internalizing problems for adolescents with less RSA suppression or RSA augmentation but not for those with greater RSA suppression. This effect was specific to stress related to marital conflict, as RSA reactivity to the mental arithmetic task and speech task did not moderate the relationship between marital conflict and internalizing problems. These findings suggest that certain profile of parasympathetic nervous activity is a risk factor for internalizing problems particularly for those who experience high-conflict environments

A New Technique for Multispectral and Panchromatic Image Fusion

AbstractIn this paper, a technique is presented for the fusion of Panchromatic (PAN) and low spatial resolution multispectral (MS) images to get high spatial resolution of the latter. In this technique, we apply PCA transformation to the MS image to obtain the principal component (PC) images. A NSCT transformation to PAN and each PC images for N level of decomposition. We use FOCC as criterion to select PC. And then, we use the relative entropy as criterion to reconstruct high-frequency detailed images. Finally, we apply inverse NSCT to selected PC's low-frequency approximate image and reconstructed high- frequency detailed images to obtain high spatial resolution MS image. The experimental results obtained by applying the proposed image fusion method indicate some improvements in the fusion performance

Robust finite-time guidance against maneuverable targets with unpredictable evasive strategies

This paper presents a robust finite-time guidance (RFTG) law to a short-range interception problem. The main challenge is that the evasive strategy of the target is unpredictable because it is determined not only by the states of both the interceptor and the target, but also by external un-modeled factors. By robustly stabilizing a line-of-sight rate, this paper proposes an integrated continuous finite-time disturbance observer/bounded continuous finite-time stabilizer strategy. The design of this integrated strategy has two points: 1) effect of a target maneuver is modeled as disturbance and then is estimated by the second-order homogeneous observer; 2) the finite-time stabilizer is actively coupled with the observer. Based on homogeneity technique, the local finite-time input-to-state stability is established for the closed-loop guidance system, thus implying the proposed RFTG law can quickly render the LOS rate within a bounded error throughout intercept. Moreover, convergence properties of the LOS rate in the presence of control saturation are discussed. Numerical comparison studies demonstrate the guidance performance