색좌표 변환을 통한 JPEG 부호화 성능 개선

Shahid Abbas,최승철(Seungcheol Choi),권오진(Oh-Jin Kwon) 한국방송·미디어공학회 2020 한국방송공학회 학술발표대회 논문집 Vol.2020 No.7

Torque Error Based Auto-tuning of Weighting Factor in Model Predictive Torque Control of Induction Motor Drive

Shahid Muhammad Bilal,Jin Weidong,Abbasi Muhammad Abbas,Husain Abdul Rashid,Hassan Mannan 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

Weighting factor design is considered a challenging and tedious task in finite control set model predictive torque control (FCS-MPTC) for induction motor drives. The complexity involved in designing the weighting factor occurs due to the presence of different quantities in the cost function. In the absence of an accurate design method, a constant weighting factor is used for entire operating range of the drive which does not guarantee optimal performance. To improve the performance of the MPTC, an online tuning method for the weighting factor is proposed in this work. The tuning process is achieved by comparing torque error to predefined threshold value at any given sampling instant. If the error is larger than the threshold limit, weighting factor is increased to bring the error within the acceptable limit and vice versa. In each sampling interval, the cost function is optimized with the tuned weighting factor and optimal voltage vector is chosen. The effectiveness of the proposed method is validated experimentally for a two level three-phase inverter-fed induction motor drive on dSpace DS1104 controller board. The performance of the proposed method is compared to the conventional MPTC with fixed weighting factor and an online weighting factor tuning method based on the principle of coefficient-of-variation (CV-MPTC). It is concluded that the proposed method not only improves dynamic performance of the drive as compared to both methods but also offers computational advantages over CV-MPTC.

Effect of calcination temperature over performance of NiO/NiAl₂O₄ catalysts for partial oxidation of methane

( Muzafar Abbas ),( Saqlain Shahid ),김상훈 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.1

Ce-Substituted Co0.5Ni0.5Fe2O4: Structural, Morphological, Electrical, and Dielectric Properties

Syed Samar Abbas,Iftikhar Hussain Gul,Shahid Ameer,Muhammad Anees 대한금속·재료학회 2015 ELECTRONIC MATERIALS LETTERS Vol.11 No.1

Functional nano ceramics, especially rare earth substituted ferrites, havenumerous applications in microelectronics. They have certain novelcharacteristics associated with various rare earth substitutions associatedwith electronics. A series of cerium-substituted cobalt nickel ferritenanoparticles with nominal composition CexCo0.5Ni0.5Fe2-xO4 (wherex = 0.00, 0.05, 0.10, 0.15, and 0.20) was prepared in powder form bychemical co-precipitation and sol-gel auto combustion methods. Sampleswere characterized by x-ray diffraction (XRD), scanning electronmicroscopy (SEM), Fourier transform infrared spectroscopy (FT-IR),dielectric properties, and DC electrical resistivity. XRD analysis of all thesamples confirms the formation of the spinel structure of Fd-3m spacegroup. Crystallite size “t” was found to decrease, whereas both x-raydensity “Dx” and lattice constant “a” were found to increase by increasingCe concentration from 8.35 Å to 8.36 Å and 8.37 Å for sol-gel and coprecipitation,respectively. SEM results show the presence of uniformlydistributed and almost spherical-shaped particles for both techniques. FTIR measurements were used to further confirm thecomposition, i.e., cation substitution. The DC electrical resistivity of the x = 0.00 sample is higher than Ce-substituted ferritesamples and in the range of 108 Ω-cm at 373 K. Dielectric spectroscopy is also studied from 100 Hz to 5 MHz as a function offrequency. To our knowledge, this is the first reported research of this particular composition.

정치적 불안정과 외국인 직접 투자: 신흥국 정부부패의 관점

시에드아사드압바스보카리 ( Syed Asad Abbas Bokhari ),무하마드아프탑 ( Muhammad Aftab ),만주르샤히드 ( Manzoor Shahid ) 산업진흥원 2021 산업진흥연구 Vol.6 No.4

파키스탄은 남아시아의 상서로운 개발도상국이다. 국제투명성기구(Transparency International)의 2020년 부패인식지수 보고서에 따르면 파키스탄은 0(최저)에서 100(최고)까지의 정치적 안정성 측면에서 전 세계적으로 총 31점으로 124위, -2.25점으로 188위를 기록했다. 더 결정적으로, 파키스탄에 대한 외국인 직접 투자의 유입은 2008년과 2019년 사이에 감소했다. 정치적 불안정과 정부 부패는 외국인 직접 투자와 양의 선형 관계와 음의 선형 관계를 모두 가지고 있지만, 본 연구에서는 시간이 지남에 따라 정치적 불안정과 외국인 직접 투자 사이의 정부 부패의 완화된 영향을 테스트했다. 또한 같은 국가의 여러 정치 체제에서 정치적 불안정과 외국인 직접 투자 사이의 관계를 테스트했다. 따라서, 본 연구의 결과는 권위주의 정권이 민주적 정부 기간보다 더 많은 외국인 직접 투자를 유치했음을 시사하였다. 더욱이, 우리는 그 나라에서 정부의 부패가 심할 때 외국인 직접 투자가 적다는 것을 발견했다. 그러나 정부의 부패는 정치적 불안정과 외국인 직접 투자(FDI) 사이의 긍정적인 관계를 약화시켰다. Pakistan is a South Asian auspicious developing country. Based on the corruption perception index report 2020 by transparency international, Pakistan has ranked 124 with total scores of 31 globally and 188 ranks with a score of -2.25 in terms of political stability ranging from 0 (lowest) to 100 (highest). More crucially, the inflow of foreign direct investment toward Pakistan has declined between 2008 and 2019. Though political instability and government corruption have both positive and negative linear relationships with foreign direct investment, we tested the moderating impact of government corruption between political instability and inward foreign direct investment over time. We also tested the relationship between political instability and inward foreign direct investment in different phases of political regimes in the same country. Our results suggested that authoritarian regimes attracted more inward foreign direct investment than that during democratic periods of government. Furthermore, we found that there was low inward foreign direct investment when government corruption was high in the country. However, government corruption weakened the positive relationship between political instability and inward foreign direct investment (FDI).

신생기업 임직원들의 조직문화와 조직몰입의 상관관계에 관한 연구

시에드아사드압바스보카리 ( Syed Asad Abbas Bokhari ),무하마드아프탑 ( Muhammad Aftab ),만주르샤히드 ( Manzoor Shahid ) 산업진흥원 2021 산업진흥연구 Vol.6 No.4

신생 기업은 선진국과 개발도상국에서 동시에 놀라운 속도로 확장하고 있다. 조직 및 인적 자원 관리 측면에서 청년 창업가들이 겪는 어려움이 많다. 결과적으로 과학계에서 거의 주목을 받지 못한 신생 기업을 조사하는 것이 중요하다. 본 연구에서는 개발도상국(파키스탄)의 중소기업(SME) 수준에서 운영되는 신생 기업만을 고려했다. 정보는 대도시 라호르에 위치한 10개 업체를 대상으로 설문조사를 통해 수집했다. 연구변수 간의 가설관계가 사실인지 여부를 확인하기 위해 상관분석을 수행하였다. 본 연구에서는 제안된 모든 가설 사이에 긍정적이고 통계적으로 유의한 연관성을 발견했다. 본 연구의 결과는 산업계, 학계 및 정책 입안자에게 중요한 의미를 갖는다. Startup enterprises are expanding at an alarming rate in both industrialized and developing countries simultaneously. Many difficulties confront young entrepreneurs in terms of organizational and human resource management. As a result, it is critical to research startup enterprises because they have received little attention from the scientific community. In this study, we solely considered new startup enterprises operating at the small and medium-sized enterprise (SME) level in a developing country (Pakistan). The information was gathered through a survey method from ten businesses located in the metropolitan metropolis of Lahore. The correlation analysis was conducted to determine whether or not the hypothesized relationship between research variables was true. We discovered a positive and statistically significant association between all of the proposed hypotheses. The findings of this study have significant implications for industry, academics, and policymakers.

Locking Compression Plate in Musculoskeletal Oncology ‘a Friend in Need’

Masood Umer,Kashif Abbas,Shahid Khan,Haroon ur Rashid 대한정형외과학회 2013 Clinics in Orthopedic Surgery Vol.5 No.4

Background: We are presenting our experience in the use of locking compression plate (LCP) after juxta-articular oncological resections in addition to its use in pathologic fracture. Methods: A retrospective audit of skeletal reconstruction using LCP in 25 cases of long bone tumors was performed from 2008 to 2010. Reconstruction following limb salvage surgery was done in 17 patients and internal fixation of pathological fracture was done in 8 patients. All patients were available for > 12 months of follow-up, and thus assessed for union at the resected ends. Results: There were 8 males and 17 females in the study. The average age at the time of surgery was 30 years (range, 9 to 66 years). The minimum follow-up was 12 months (range, 12 to 32 months). All patients except three went on to heal successfully. Complications occurred in those three patients: wound infection in one, nonunion in another, and periprosthetic fracture in the other patient. In the remaining patients, union was achieved at an average of 6.5 months after reconstruction in curative resection and 4.75 months after fixation of pathological fractures. Conclusions: Joint sparing limb salvage surgery was made successfully possible after sekeletal reconstruction with LCP. Its use was also quite effective in pathological fractures with poor bone quality. Use of locking plates for musculoskeletal oncological reconstruction resulted in a good and predictable rate of union.

Genetic Variability among Different Populations of Root Knot Nematodes Based on Their Encumbrance Response to Pasteuria Isolates Using PCR-RFLP

Kamran, Muhammad,Javed, Nazir,Ullah, Ihsan,Nazir, Shahid,Jamil, Shakra,Iqbal, Muhammad Zafar,Abbas, Huma,Khan, Sajid Aleem,Haq, Muhammad Ehetisham ul The Korean Society of Plant Pathology 2019 Plant Pathology Journal Vol.35 No.1

A great variable response was observed when PP-3 and PP-J encumbered with 116 populations of root knot nematode (RKN) at two different temperatures ($25{\pm}2^{\circ}C$ and $30{\pm}2^{\circ}C$) and concentrations ($10^4$ and $10^5$ spores/ml). The PCR reaction amplified intergenic region between cytochrome oxidase subunit II gene (COII) and large subunit of rRNA gene (lrRNA) of the mitochondrial genome of different RKN species. The primer C2F3 and 1108 identified M. incognita with the highest frequency (52.6%) followed by M. javanica (36.8%) and M. arenaria (10.5%). The sizes of PCR products were 1.7 kb for M. incognita and M. javanica populations while populations of M. arenaria produced 1.1 kb fragment. The digestion with Hinf I yielded three different fragment length patterns on 1.5 % agarose gel. From current research it is concluded that intra-Meloidogyne genetic variability exist in RKN populations which have better encumbrance with P. penetrans.

Genetic Variability among Different Populations of Root Knot Nematodes Based on Their Encumbrance Response to Pasteuria Isolates Using PCR-RFLP

Muhammad Kamran,Nazir Javed,Ihsan Ullah,Shahid Nazir,Shakra Jamil,Muhammad Zafar Iqbal,Huma Abbas,Sajid Aleem Khan,Muhammad Ehetisham ul Haq 한국식물병리학회 2019 Plant Pathology Journal Vol.35 No.1

A great variable response was observed when PP-3 and PP-J encumbered with 116 populations of root knot nematode (RKN) at two different temperatures (25 ± 2°C and 30 ± 2°C) and concentrations (104 and 105 spores/ml). The PCR reaction amplified intergenic region between cytochrome oxidase subunit II gene (COII) and large subunit of rRNA gene (lrRNA) of the mitochondrial genome of different RKN species. The primer C2F3 and 1108 identified M. incognita with the highest frequency (52.6%) followed by M. javanica (36.8%) and M. arenaria (10.5%). The sizes of PCR products were 1.7 kb for M. incognita and M. javanica populations while populations of M. arenaria produced 1.1 kb fragment. The digestion with Hinf I yielded three different fragment length patterns on 1.5 % agarose gel. From current research it is concluded that intra-Meloidogyne genetic variability exist in RKN populations which have better encumbrance with P. penetrans.

Characterizing Barium Titanate Piezoelectric Material Using the Finite Element Method

Butt, Zubair,Rahman, Shafiq Ur,Pasha, Riffat Asim,Mehmood, Shahid,Abbas, Saqlain,Elahi, Hassan The Korean Institute of Electrical and Electronic 2017 Transactions on Electrical and Electronic Material Vol.18 No.3

The aim of the current research was to develop and present an effective methodology for simulating and analyzing the electrical and structural properties of piezoelectric material. The finite element method has been used to make precise numerical models when dielectric, piezoelectric and mechanical properties are known. The static and dynamic responses of circular ring-shaped barium titanate piezoelectric material have been investigated using the commercially available finite element software ABAQUS/CAE. To gain insight into the crystal morphology and to evaluate the purity of the material, a microscopic study was conducted using a scanning electron microscope and energy dispersive x-ray analysis. It is found that the maximum electrical potential of 6.43 V is obtained at a resonance frequency of 35 Hz by increasing the vibrating load. The results were then compared with the experimentally predicted data and the results agreed with each other.