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      • SCOPUS

        The Relationship Between Oil Price Fluctuations, Power Sector Returns, and COVID-19: Evidence from Pakistan

        Sajjad AHMED,Khalil Ullah MOHAMMAD 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.3

        Oil prices have become more volatile as a result of global economic contraction and control measures. Before and during the COVID-19 crisis, this study examines the relationship between oil price swings and daily stock returns in the power sector. The impact is investigated using a panel Vector Autoregressive (VAR) model. Granger causality tests are used to see if oil prices are effective in predicting returns. The dynamic impact of supply shocks is studied using Impulse Response Functions (IRFs). From January 2011 to May 2021, the study used daily data from all listed power sector enterprises on the Pakistan stock exchange. To investigate the differences in reactions between the Pre-COVID and COVID eras, the sample was separated into two groups. Oil shocks are inversely associated with daily firm stock returns. The conclusions are further supported by the lack of impact of stock prices on oil prices. The relationship, however, deteriorates during the COVID pandemic. We could not uncover any evidence of a significant relationship. In developing countries that rely on oil imports, the study sheds light on the utility of oil price shocks in daily stock return predictions.

      • Emotion Recognition of Low Resource (Sindhi) Language Using Machine Learning

        Ahmed, Tanveer,Memon, Sajjad Ali,Hussain, Saqib,Tanwani, Amer,Sadat, Ahmed International Journal of Computer ScienceNetwork S 2021 International journal of computer science and netw Vol.21 No.8

        One of the most active areas of research in the field of affective computing and signal processing is emotion recognition. This paper proposes emotion recognition of low-resource (Sindhi) language. This work's uniqueness is that it examines the emotions of languages for which there is currently no publicly accessible dataset. The proposed effort has provided a dataset named MAVDESS (Mehran Audio-Visual Dataset Mehran Audio-Visual Database of Emotional Speech in Sindhi) for the academic community of a significant Sindhi language that is mainly spoken in Pakistan; however, no generic data for such languages is accessible in machine learning except few. Furthermore, the analysis of various emotions of Sindhi language in MAVDESS has been carried out to annotate the emotions using line features such as pitch, volume, and base, as well as toolkits such as OpenSmile, Scikit-Learn, and some important classification schemes such as LR, SVC, DT, and KNN, which will be further classified and computed to the machine via Python language for training a machine. Meanwhile, the dataset can be accessed in future via https://doi.org/10.5281/zenodo.5213073.

      • KCI등재

        A Comparison of Productivity by Variety, Plantlet Size and Planting Period to Improve Aeroponic Seed Potato System in Pakistan

        Waqas Ahmed Dogar,Aish Muhammad,Gyoung-Rae Cho,Muhammad Hanif,Kazim Ali,Asad Farooq,Asma Akbar,Sajjad Ahmed,Hoyong Shin 한국국제농업개발학회 2023 韓國國際農業開發學會誌 Vol.35 No.2

        An aeroponic seed potato production technology project has been established in Pakistan through the Technical Cooperation Project (TCP) between RDA-KOPIA and PARC. For sustainable potato production, producing high-quality and disease-free potato seeds is critical in Pakistan. The majority of the farmers recycle their own seeds or obtain them through informal ways. Consequently, tuber-borne illnesses proliferate, seeds deteriorate, and yield diminishes. To mitigate such problems, the country moved to sustainable seed potato production by adopting rapid seed multiplication strategies like the combination of tissue culturing with aeroponic seed production technology which is being evaluated as an alternative to traditional pre-basic seed production methods. A series of experiments were carried out to evaluate the shoot development and mini tuber production attributes between two cultivars, different plantlet size and planting period between October 27, 2021, and January 27, 2022, at the NARC aeroponic facility. A CRD design with three replications was used. The study aimed to compare the productivity by variety, plantlet size and planting period to improve aeroponic seed production technology in Pakistan. The results indicated that Lady Rosetta outperformed Asterix in terms of shoot growth and small tuber output. Early planting at an optimal temperature of 27 degrees Celsius in the daytime showed a substantial difference when compared to late planting in November and tuberization was commenced 50-55 days after transplantation. Furthermore, in an aeroponic seed potato production system, normal plantlets (8-10 cm) at the time of transplantation, performed better than medium and small plantlets. In a nutshell, it was determined that normal size plantlets (8-10 cm) of Lady Rosetta cultivar, planted at optimum time to plant showed best results in the aeroponic system at NARC, Islamabad, Pakistan.

      • SCIESCOPUSKCI등재

        Power electronic converter reliability and prognosis review focusing on power switch module failures

        Abuelnaga, Ahmed,Narimani, Mehdi,Bahman, Amir Sajjad The Korean Institute of Power Electronics 2021 JOURNAL OF POWER ELECTRONICS Vol.21 No.6

        The current trend is to go for more electric systems that rely extensively on power electronics such as EVs/HEVs and electric aircrafts, along with an increased use of renewable energy resources and variable speed motor drives. However, some field failure reports have revealed that power electronic converters represent the weakest point in these systems. A significant percentage of system failures are due to power electronic converter failures, which compromises systems reliability. This raises questions regarding the validity of relying on the current power electronic converter technology to run mission-critical/must-to-be-safe systems. Although power electronic converter technology has reached an advanced level in terms of efficiency, power density, and control, extra work should be done when it comes to reliability. Reliability engineering brings performing failure data analysis, accelerated life testing, lifetime prediction, and the implementation of efficient maintenance and reliability improvement schemes into an integrated process. This process is meant to enhance the reliability of a product throughout its life cycle. This paper provides an overview of the application of the key aspects of new approaches in reliability engineering for power electronic converters. The focus of this paper is on power switch bond-wire modules since they are the most vulnerable component in power electronic converters. This paper also proposes two general schemes for condition-based remaining useful lifetime (RUL) that are discussed in detail.

      • Complete genome sequencing and analysis of endophytic <i>Sphingomonas</i> sp. LK11 and its potential in plant growth

        Asaf, Sajjad,Khan, Abdul Latif,Khan, Muhammad Aaqil,Al-Harrasi, Ahmed,Lee, In-Jung Springer International Publishing 2018 3 Biotech Vol.8 No.9

        <P>Our study aimed to elucidate the plant growth-promoting characteristics and the structure and composition of <I>Sphingomonas</I> sp. LK11 genome using the single molecule real-time (SMRT) sequencing technology of Pacific Biosciences. The results revealed that LK11 produces different types of gibberellins (GAs) in pure culture and significantly improves soybean plant growth by influencing endogenous GAs compared with non-inoculated control plants. Detailed genomic analyses revealed that the <I>Sphingomonas</I> sp. LK11 genome consists of a circular chromosome (3.78 Mbp; 66.2% G+C content) and two circular plasmids (122,975 bps and 34,160 bps; 63 and 65% G+C content, respectively). Annotation showed that the LK11 genome consists of 3656 protein-coding genes, 59 tRNAs, and 4 complete rRNA operons. Functional analyses predicted that LK11 encodes genes for phosphate solubilization and nitrate/nitrite ammonification, which are beneficial for promoting plant growth. Genes for production of catalases, superoxide dismutase, and peroxidases that confer resistance to oxidative stress in plants were also identified in LK11. Moreover, genes for trehalose and glycine betaine biosynthesis were also found in LK11 genome. Similarly, <I>Sphingomonas</I> spp. analysis revealed an open pan-genome and a total of 8507 genes were identified in the <I>Sphingomonas</I> spp. pan-genome and about 1356 orthologous genes were found to comprise the core genome. However, the number of genomes analyzed was not enough to describe complete gene sets. Our findings indicated that the genetic makeup of <I>Sphingomonas</I> sp. LK11 can be utilized as an eco-friendly bioresource for cleaning contaminated sites and promoting growth of plants confronted with environmental perturbations.</P><P><B>Electronic supplementary material</B></P><P>The online version of this article (10.1007/s13205-018-1403-z) contains supplementary material, which is available to authorized users.</P>

      • KCI등재

        Driving force for forest fragmentation explored by land use change in Song watershed, India

        Mehebub Sahana,Raihan Ahmed,Purva Jain,Haroon Sajjad 대한공간정보학회 2016 Spatial Information Research Vol.24 No.6

        This study attempts to assess forest fragmentation and degradation in response to land use/land cover changes in Song watershed, India during 1998–2014. Landsat TM and Landsat 8 OLI satellite data across two dates (1998 and 2014) were used to analyze land use/land cover change and its impact on forest cover. The extent of forest degradation was analyzed using fragmentation model. Four categories of disturbance viz. core, perforated, edge and patch were obtained using 200 meters edge width. The result shows overall decrease of 7% in area under forest over 16 years. Area under open forest, mixed land use/land cover I (agriculture, forest and built up) and mixed land use/land cover III (agriculture and built up) has significantly increased while area under dense forest has decreased during the study period. Fragmentation model revealed lots of disturbance in forest located in mixed land use/land cover areas. Perforated and patch classes of forest have experienced a significant increase in their respective areas while core area has decreased at the expense of other fragmentation classes. Degradation of forest occurred at large scale at Hrishikesh and Thano forest ranges of Dehradun district and Gadol range in Tehri Garhwal district lying in the watershed. Rishikesh city in Dehradun district located in southern part of watershed recorded increase in patches due to developmental activities. Remote sensing and fragmentation model showed their effectiveness in analyzing forest degradation and monitoring the health of the forest in the watershed.

      • KCI등재

        Hybrid Indoor Position Estimation using K-NN and MinMax

        ( Fazli Subhan ),( Shakeel Ahmed ),( Sajjad Haider ),( Sajid Saleem ),( Asfandyar Khan ),( Salman Ahmed ),( Muhammad Numan ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.9

        Due to the rapid advancement in smart phones, numerous new specifications are developed for variety of applications ranging from health monitoring to navigations and tracking. The word indoor navigation means location identification, however, where GPS signals are not available, accurate indoor localization is a challenging task due to variation in the received signals which directly affect distance estimation process. This paper proposes a hybrid approach which integrates fingerprinting based K-Nearest Neighbors (K-NN) and lateration based MinMax position estimation technique. The novel idea behind this hybrid approach is to use Euclidian distance formulation for distance estimates instead of indoor radio channel modeling which is used to convert the received signal to distance estimates. Due to unpredictable behavior of the received signal, modeling indoor environment for distance estimates is a challenging task which ultimately results in distance estimation error and hence affects position estimation process. Our proposed idea is indoor position estimation technique using Bluetooth enabled smart phones which is independent of the radio channels. Experimental results conclude that, our proposed hybrid approach performs better in terms of mean error compared to Trilateration, MinMax, K-NN, and existing Hybrid approach.

      • CA 15-3 (Mucin-1) and Physiological Characteristics of Breast Cancer from Lahore, Pakistan

        Begum, Mumtaz,Karim, Sajjad,Malik, Arif,Khurshid, Rukhshan,Asif, Muhammad,Salim, Asmat,Nagra, Saeed Ahmed,Zaheer, Ahmad,Iqbal, Zafar,Abuzenadah, Adel Mohammed,Alqahtani, Mohammed Hussain,Rasool, Mahmo Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.10

        Background: High incidence of breast cancer and its fatal effect has reached an alarming stage across the globe, including the third world countries. Many factors have been reported to be associated with the development of breast cancer but detailed structural and functional information is missing. CA 15-3 is one of the known potential tumor marker of breast cancer; however little is known about structure and functional site of this protein. Present study aims to investigate the functional role of CA 15-3 in breast cancer, especially in development and metastasis. Material and Methods: Hundred female breast cancer patients confirmed by histopathological reports were included in the study. Their physiological characters were recorded in a performa. Enzyme linked immunosorbent assay (ELISA) technique was used to estimate serum CA 15-3 level. Immunohistochemistry was done for estrogen (ER), progesterone (PR) and Her2/neu receptors expression. Results: The study revealed the details of physiological characteristics of female breast cancer. Mean age was $37.72{\pm}5.99$ and $55.05{\pm}7.28$ years and serum CA 15-3 (MUC1) level was $60.47{\pm}8.59$ and $63.17{\pm}4.58$ U/ml in pre and post-menopause respectively, and both groups of women had sedentary life style. Their receptor status especially of progesterone, estrogen and HER-2/neu were positive in 50% of premenopausal women and 65% of postmenopausal women. Conclusion: There are multiple physiological factors promoting breast cancer. High serum CA 15-3 level and hormonal imbalance of ER, PR and Her2/neu appears to be the main cause of breast cancer. It may be possible that the functional sites of these proteins may be altered which may increase the chances of metastasis in breast cancer.

      • KCI등재

        Land suitability assessment for optimal cropping sequences in Katihar district of Bihar, India using GIS and AHP

        Vinay Prasad Mandal,Sufia Rehman,Raihan Ahmed,Md. Masroor,Pavan Kumar,Haroon Sajjad 대한공간정보학회 2020 Spatial Information Research Vol.28 No.5

        The main objective of the study is to assess land suitability for suggesting suitable crop sequences in Katihar district of Bihar, India. We first selected site-specific factors and assigned their weights using analytical hierarchy process (AHP) for land suitability assessment. The layers of factors were integrated to prepare land suitability map. The findings revealed that of the total area (3.05 million ha), the largest area (48.5%) was marginally suitable for agriculture followed by moderately suitable (30.8%) and highly suitable (2.9%). Nearly 17.8% area was found unsuitable for agriculture. Rice–maize– rice, rice–maize–jute and maize–maize–rice were found suitable crop sequences in all suitability classes. Multilinear regression analysis between land suitability and factors shows that soil texture, nitrogen, phosphorus and potassium, pH and drainage proximity influenced land suitability. The study suggested soil reclamation, application of adequate amount of fertilizers, assured irrigation and flood control for sustainable crop sequences in the study area. Land restoration and soil reclamation measures should be taken to transform unsuitable areas for crop cultivation. Use of integrated geographical information system and AHP approach for analyzing land suitability and crop sequences may add a new dimension in spatial information science.

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