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Indian jujube (Ziziphus mauritiana Lamk.) is a drought tolerant fruit crop and well adapted to sub-tropical to tropical climates. Seasonal pruning in jujube is essential to sustain the plants as productive with quality fruits because flowers and fruits are borne on young shoots of current season’s growth. This experiment was initiated and accomplished during 2016-18 to assess appropriate extent of pruning in various cultivars of Indian jujube with regard to productivity and fruit quality. Four cultivars of jujube i.e., Dehli Sufaid, Pak White, Umran and Alu Bukhara were subjected to four pruning levels i.e. no pruning, 25%, 50% and 75% pruning by removing unproductive, over-crowded secondary and tertiary branches leaving 3/4 (light), 1/2 (medium) and 1/4 (severe pruning) portion of branch intact with main limb, respectively. Experiment was laid out in randomized complete block design with three replications and statistically analysed in 2-factors factorial way. Pak White initiated new growth earlier (39 days), produced maximum branches per plant (77), shoots (15), panicles (63) and fruits (90) per branch, heavier (38 g) and bulky fruits (44 cm3), with minimum fruit drop (13%), higher yield (184 kg) per plant and fruits carrying the maximum pulp ratio (90%), total soluble solids (16 °Brix), vitamin C content (121 mg /100 g pulp) and total sugars (5.7%). Fifty percent pruning level proved more judicious in all jujube cultivars. Pak White performed the best when subjected to 50% pruning level for all the parameters under study as calculated by interaction between two factors.

Application of green manures substitutes use of chemical fertilizers, improves soil health, prevents soil degradation also ensures food security. Two years’ field experiment was laid out to determi...

Mango being one of the most important fruit crops in Pakistan is facing a serious issue of malformation. If it is not treated, it renders great economical losses. Samar Bahisht Chaunsa is an excellent quality exportable cultivar of mango, but it is also the most vulnerable to inflorescence malformation. Therefore, the present study was carried out to address the malformation issue in mango cv. Samar Bahisht Chaunsa during 2016-18. The treatments comprised of pruning during March, pruning during April, pruning during March along with spray of Topsin-M @ 2 g L-1, pruning during April along with spray of Topsin-M @ 2 g L-1 and leaving plants un-pruned without spray as control. The tree branches were pruned up to 20 cm beneath the malformed inflorescences. Data on number of days taken to initiate growth, number of emerged flushes, number of bloomed flushes and number of malformed inflorescences were recorded. Pruning during March in combination with 2 g L-1 Topsin-M spray significantly affected all the parameters. The minimum number of days (37) taken for growth initiation, the highest number of emerged flushes (3.5) as well as bloomed flushes (3.2) along with the least number of malformed inflorescences (1.4) were recorded for the aforementioned treatment. Un-pruned and non-sprayed branches (control) did not initiate growth.

Monsoon crop of guava is hit by fruit fly during July-August that results into huge loss to the producers. Spray of urea and Naphthalene acetic acid (NAA) is used to drop flowers and fruits of monsoon crop to get higher yield of winter crop. This study was carried out at Fruit Orchard of Horticultural Research Station, Bahawalpur during 2015-2017 to determine the optimum concentration of selected chemicals to drop flowers and immature fruits of monsoon crop. Plants with distilled water spray were treated as control (T1). Other treatments included urea @ 5% and 10% (T2 & T3), NAA @ 0.05 and 0.1% (T4 & T5) as 1st spray and repeated the same spray after fortnight, combination of urea (5%) as 1st spray followed by NAA (0.05%) as 2nd spray (T6) or urea (10%) 1st spray followed by NAA (0.1%) as 2nd spray (T7). Consolidated means of parameters over two years’ study indicated that the highest fruit yield (68.6 kg/plant), the maximum weight per fruit (168.3 g), number of fruit/plant (375), pulp content (55.5%), pulp thickness (1.05 cm), total soluble solids (14.3 °Brix), ascorbic acid content (176.7 mg / 100 g pulp) and total sugars (7.6%) were obtained as a result of highest flower drop (96.7%) and fruit drop (76.9%) with lowest fruit set (2.9%) from non-target monsoon fruiting in response to 0.1% NAA (T5) sprayed twice at fortnight interval, proceeded after the application of 0.05% NAA two spray fortnightly (T4). The plants under control remained at bottom with respect to parameters i.e. flower and fruit drop, at top with highest fruit setting in monsoon crop that led to the lowest yield of winter crop.

Pomegranate is a drought tolerant fruit crop and is well adapted to sub-tropical and tropical climates. Fruit cracking is a major disorder in pomegranate which causes significant economic losses. In the present work, effect of foliar application of boric acid (0.05%), potassium nitrate (1.0%) and magnesium sulphate (1.0%) alone or in combinations was investigated to manage fruit cracking and improve fruit yield and quality of pomegranate cv. Golden. First treatment (foliar spray) was applied one month after fruit setting (April) and repeated twice during May and June each year. Application of foliar sprays affected fruit yield and quality positively. The maximum number of fruits per plant (254), average fruit weight (192 g), yield per plant (58.3 kg), number of arils per fruit (592), juice content (41.1%) as well as the minimum fruit cracking (3.9%) were recorded when 0.05% boric acid, 1% potassium nitrate and 1% magnesium sulphate were applied in combination. Fruit size and total soluble solids (TSS) of fruit juice were not affected by the applied treatments. Thus, combined application of boric acid, potassium nitrate and magnesium sulphate could be recommended for reducing fruit cracking and improving yield and quality of pomegranate fruits under semi-arid conditions of Southern Punjab, Pakistan.

Higher degrees of freedom (DOF) for direction of arrival can be attained by using coprime arrays. In this paper, we design super-resolution generalized coprime array configurations based on suppression and displacement to achieve higher DOFs. The first composition known as CASDiS stands for coprime arrays with suppressed and displaced subarrays. This structure can achieve $$ 4MN + 1 $$ number of consecutive lags considering only $$ 2M + N $$ number of sensors. However, still there are some holes. In order to achieve hole-free lags, a novel nested inspired “Nested Displaced CoPrime subarrays” (NesDCoP) structure is designed. This configuration performs remarkably in terms of generating consecutive lags and can triumph hole-free $$ 4MN + 2M + 1 $$ lags. The key contributions of this work are as follows: Firstly, both array configurations can achieve longer consecutive lags as compared to previously proposed arrays. Secondly, NesDCoP structure can accomplish consecutive lags almost equivalent to nested arrays. Lastly, both structures are less complex because there is no need to use interpolation techniques. The practicality of these configurations is demonstrated using MUSIC algorithm, and then, simulation results are equated with other methods which show the effectiveness of both the proposed array configurations.

In this paper, a novel array structure exploiting coprime arrays is proposed which can be very proficient to determine the number of consecutive lags in proportion with the number of array elements. The proposed method comprises novel array structure by configuring three subarrays positioned in alignment with some prescribed values. By increasing array elements in third subarray while keeping other subarrays fixed, explicit number of consecutive lags could be obtained proportionately. The proposed method offers maximization of consecutive lags in remarkable number by calculating the fourth order difference co-array unifying interpolation. The forth order difference co-array is achieved by exploiting the second order difference co-array twice. The consideration of third subarray in addition with two coprime subarrays leads to a novel array structure which can significantly enhance degrees of freedom. An effective interpolation technique nuclear norm minimization is considered to fill the holes subsisting in the virtual co-array in order to exploit full virtual co-array length. This interpolation method uses convex framework which is trackable and very simple to implement yielding a freedom of fixing any predefined extra tuning parameter. The proposed method in this paper is named as VEFODCI which stands for virtual extension of coprime arrays by exploiting fourth order difference co-array with interpolation. The sparse Bayesian learning is used for direction of arrival (DOA) estimation exploiting the proposed novel array structure by imposing interpolation to fill the holes. The array geometry of sensor distributions proves that the proposed method is less susceptible from mutual coupling effect. The simulation results stipulate that the proposed method is performing DOA estimation accurately even in lower angular separation of sources by achieving larger number of consecutive lags than the state of the art.

The efficiency of two dimensional (2-D) Direction of Arrival (DOA) estimation relies on the geometry of array. Among many array geometries, L-type array structure is becoming more popular among researchers because it can be decoupled into two uniform linear arrays (ULAs) and require less number of array elements as compared to other planar arrays. This paper propose a novel, fast and low complexity method for joint estimation of range and 2-D DOAs (elevation and azimuth) of near field sources. The main focus of this paper is to present the efficacy of performance and ease in implementation of L-type array structure when it is integrated with Differential Evolution (DE), a global evolutionary optimizer. To avoid the pair matching of estimated parameters, mean square error is used as fitness evaluation function as it only requires a single snapshot of array output to achieve optimal convergence. The robustness of proposed method is tested by a large number of computer simulations and statistical performance analysis is compared with other techniques.

A new rank reduction (RARE)-based two-dimensional (2-D) direction of arrival (DOA) estimation algorithm is proposed considering a mixture of circular and strictly noncircular sources. To enhance array aperture, a geometry of three uniform linear arrays is considered and then treated as displaced arrays from a virtual array using a simple linear transformation. The received data and the conjugated counterpart are combined together, exploiting the noncircular property. Both sources can be estimated separately by designing and exploiting the distinctive nature of circular and noncircular steering vectors. However, a 2-D spectrum search would lead to a high computational complexity burden. To reduce this high computational complexity burden, a novel RARE-based method is proposed, which plays a vital role by decomposing 2-D observation space into two successive 1-D peak search functions. The proposed method has some distinctive advantages: it can enhance the array aperture utilization, it can provide better estimation accuracy when mixed sources are greater than the number of sensors, it can estimate a larger number of mixed sources than the number of sensors, and finally it can automatically pair 2-D DOAs without any complicated pairing formulation. Extensive simulation results are provided to demonstrate the effectiveness of the proposed method.

For the next generation wireless communication system, Multi carrier Code Division Multiple Access (MC-CDMA) has become very appealing scheme due to due to high data rates and interference limiting factors. In this research work we analyzes the capacity of MC-CDMA system using adaptive power and sub-channel allocation under perfect, imperfect and predicted channel state information (CSI). The transmitter and receiver both have been targeted in this paper. The proposed scheme is a novel idea that divides the sub-channels into small groups. Each group is assigned power according to the Eigen values and gain of the each sub-channel in that specific group. The receiver calculates optimal feedback vector for the transmitter by calculating the bit error rates using the above strategy and selects the optimal feedback vector. The simulations show that the usage of joint power and sub-channel allocation outperforms the capacity of the system. The capacity of the system is highly improved using adaptive power and sub-carriers allocation along with CSI prediction. The simulation results have been carried out for other power allocation schemes available in literature and results have been compared with perfect, imperfect and predicted CSI.

Multi input multi output (MIMO) is a multifarious and captivating technology due to its high data rate and capacity. In this research work, the authors have proposed a novel successive interference scheme for un-coded MIMO spatial multiplexing system with multiple interference cancellation structure. The multi branch multiple feedback successive interference cancellation (MB-MF-SIC) employees multiple SIC in parallel according to ordering of the received signal. The branch which yields best performance is selected which in turn gives higher detection diversity. The arrangement of the layers demolish the propagation of error in the feedback loop and hence enhances the bit error rate performance. Simulation results show that the combination of MB-MF-SIC and the ordering of the layers named Multi Branch Layers Ordered Multiple Feedback SIC (MB-LOMF-SIC) significantly improves the results compared to the existing MF-SIC and conventional SIC schemes.

Wireless and mobile communications play vital role in the field of information and communications technologies (ICT) to have an excellent internet mobility (4G and beyond). In this domain, design of efficient and robust MU-MIMO systems is a challenge for researchers. In this paper, we have proposed a new algorithm named as Layers Ordered Multiple Feedback Successive Interference Cancellation (LOMF-SIC). It is based on Spatial Multiplexed (SM), for uncoded MU-MIMO systems. Proposed algorithm has intrinsic novel idea that exploits the arranging layers according to the decreasing order of channel norm, SNR and SINR values of the received symbols. Arrangements of layers mitigate error propagation in the feedback loop and enhance BER performance. Furthermore, we have also proposed Division of Constellation Diagram (DCD) algorithm used to decide the reliability or unreliability of the detected symbols with low complexity. Simulation results are very encouraging and have shown that combination of our proposed algorithms has outperformed the existing techniques of SNR and channel norm. Simulation results have also shown that LOMF-SIC based on SINR has outperformed MF-SIC and conventional SIC methods.

Femtocells are used to enhance the service coverage inside the office or home, particularly where access is narrow or engaged. Femtocells enhance the service quality that is attractive for the client and the mobile operator. Currently, security of core network from the unauthorized user in public environment is a big issue and there is no integrated solution to verify a rouge femtocell or unauthorized user equipment (UE). Forged equipment can launch any attack or hack the core network to act actively or passively. Hence, there is a need for a mutual authentication protocol, so communication equipments can verify each other during connection establishment and make a secure tunnel for communication. In this paper we have critically analyzed the Rapid Development Authentication Protocol (RDAP) and its structural design. Then a novel protocol has been proposed which provide mutual authentication between User Equipment (UE) and femtocell that will make the system more secure than conventional RDAP. Moreover, novel scheme is also compatible with the current network architecture and resist various network attacks e.g., Sybil attack, MITM, DOS, Eavesdropping & Injecting attack and Packet Sniffing.