Unique Determination of the Shape of a Scattering Screen from a Passive Measurement

We consider the problem of fixed frequency acoustic scattering from a sound-soft flat screen. More precisely, the obstacle is restricted to a two-dimensional plane and interacting with an arbitrary incident wave, it scatters acoustic waves to three-dimensional space. The model is particularly relevant in the study and design of reflecting sonars and antennas, cases where one cannot assume that the incident wave is a plane wave. Our main result is that given the plane where the screen is located, the far-field pattern produced by any single arbitrary incident wave determines the exact shape of the screen, as long as it is not antisymmetric with respect to the plane. This holds even for screens whose shape is an arbitrary simply connected smooth domain. This is in contrast to earlier work where the incident wave had to be a plane wave, or more recent work where only polygonal scatterers are determined.Peer reviewe

Impact of Liquidity Risk on Banks (A Case Study of Punjab, Pakistan)

The main reason or purpose of this research is to find out the impact of liquidity risk on banking sector. Bank and risk are two things that cannot be separated from each other. One of the critical risk is liquidity risk that caused by bank disabilities on meeting their maturity dates of depositors. Therefore it needs further observations to control their liquidity risk. In this study simple linear regression is used through SPSS to investigate the influence between dependent and independent variable such as Return on Equity, Return on Asset, Current Ratio, Capital Adequacy Ratio, belongs to liquidity risk on banking industry. The selection of samples uses purposive sampling method. The study is based on secondary data in a period of 20 years, i.e. 1991-2011. The statistical  analysis  of  secondary  data  has  been  divided  into  three,  which  are  descriptive, regression and hypothesis testing. The study finds negatively and significant influence of Capital Adequacy Ratio and Return on Equity to liquidity risk, while Return on Asset and Current Ratio have positively and significant effect. Return on Asset and Current Ratio influences to liquidity risk is positive and in same direction (upward) while Return on Equity and, Capital Adequacy Ratio influences to the liquidity risk is negatively and in opposite direction (downward).Return on Equity and Capital Adequacy Ratio Increases the Liquidity Risk will decreases, while Return on Asset and Current Ratio increases then Liquidity Risk will also increases. Keyword: Liquidity Risk. Return on asset (ROA). Return on equity (ROE). Current Ratio (CR), Capital Adequacy Ratio (CAR

Unique Determination of a Planar Screen in Electromagnetic Inverse Scattering

The target of our research is the object being a highly conducting thin plate or a flat screen. We especially focus on the question of when a single measurement uniquely determines an object. By this, we mean that we have one fixed transmitted wave and the resulting scattered field is measured for all directions in the far field. Such measurements are called passive, since there is no need to move the transmitter after its position has been fixed. We show that the far field of a scattered electromagnetic field corresponding to a single incoming plane wave always uniquely determines a bounded super-conductive planar screen. This generalises a previous acoustic result

Effect of Foliar Supplied PGRs on Flower Growth and Antioxidant Activity of African Marigold (Tagetes erecta L.)

Marigold is one of the commercially exploited flowering crops that belongs to the family Asteraceae. The production of economical yield and better quality of marigold flowers requires proper crop management techniques. Crop regulation is an important technique to make the marigold production profitable. This can be done by adopting application of plant growth regulators (PGRs). The present study was designed to investigate the effect of PGRs on flowering and antioxidant activity of two cultivars of African marigold (Tagetes erecta L.) viz. “Pusa Narangi Gainda” (hereinafter referred to as Narangi) and “Pusa Basanthi Gainda” (hereafter referred to as Basanthi). Plants were sprayed with abscisic acid (ABA), N-acetyl thiazolidine (NAD), gibberellic acid (GA3), salicylic acid (SA), indole-3-butyric acid (IBA) and oxalic acid (OA) at the concentrations of 100, 150, 250, 300 and 800 mg·L−1, each. Results revealed that the plants treated with 500–600 mg·L−1 IBA exhibited maximum increase in floral diameter (34–51%). The use of 500–550 mg·L−1 IBA exhibited maximal enhancement in flower fresh weight (21–92%). The exogenously applied OA significantly (p ≤ 0.05) improved flower dry weight, total phenolic contents, total flavonoid contents and reducing power ability of marigold plants. Overall, “Narangi” performed better than “Basanthi”, in terms of flowering and antioxidant activity. Conclusively, the results suggest that foliar application of PGRs favors flowering and antioxidant activity of African marigold