Hardware implementation of unified two dimensional Discrete Cosine Transform computation for Ultra-High Definition

Meeturani Jagdishram Sharma 건국대학교 대학원 2012 국내석사

In this research work, a fast and cost-effective algorithm for computing the two-dimensional 4×4 integer transform using the 8×8 integer transform for H.264 is presented. It is shown that both 4×4 and 8×8 integer transforms can be implemented by simple addition operations by Kronecker product and direct sum operations. The 4×4 and 8×8 integer transforms are broken into stages, and by inserting input reordering matrices, about half of the blocks of the 4×4 integer transform are implemented via stages of the 8×8 integer transform. The dual clock pipelined architecture is proposed based on integer matrix decomposition of forward transform. The synthesis result shows that the proposed design requires approximately 46K gates. The design achieves a throughput of 14G pixels/sec for 4×4 integer transform computation and 18.7G pixels/sec for 8×8 integer transform computation. The proposed architecture has 2 times the throughput of the other existing architectures with smaller resource consumption. Due to the high throughput to area ratio, the proposed design can effectively be integrated into real-time processing of H.264/AVC high definition video.

Optimal control strategy, multi-echelon efficiency decomposition and variable prioritization for closed loop serial supply chain

Sharma, Mithun Jagadish Korea Maritime Univ. 2011 국내박사

Developmental states and serendipitous outcomes : a comparative study of economic growth, income inequality, and human well being in Mexico and South Korea

Sharma, Isha UMI 2004 국내박사

(A) study of electronic and spin transport properties in metals and 2D-vdW layered materials : Spintronics

Sharma, Pradeep Raj 세종대학교 대학원 2022 국내박사

Two-dimensional (2D) van der Waals (vdW) layered materials have attracted immense attention and shown their potential applications mainly in the field of electronics, opto-electronics, spintronics, and quantum devices. This thesis comprises a study of electronic and spintronic phenomena in metals and 2D vdW layered materials as well as a fabrication of an electric and opto-electric device based on the 2D materials. First, spin valve effects in current perpendicular-to-plane (CPP) and current-in-plane (CIP) configurations are presented. In the CPP configuration, a vertical spin valve (VSV) effect is studied on NiFe/CVG-Gr/Co structure, where single-layer (SL) and double-layer (DL) CVD graphene grown in copper foil is used as an intermediate layer between the top and bottom FM electrodes. Polymethyl methacrylate (PMMA) free dry transfer of CVD graphene along with e-beam and photo-resist free fabrication procedure results in a significant enhancement of the magnetoresistance (MR) effect. More importantly, the MR signals obtained here are free from probable spurious effects. In the CIP configuration, a lateral spin valve (LSV) effect is studied, where a PMA [CoSiB/Pt]N=7 multilayer electrode is used to inject a out-of-plane polarized spin current to a copper (Cu) channel and another adjacent PMA electrode is used to detect the spin current. The non-local MR values reported here are about 2 orders of magnitude higher than the results published before using other PMA materials. The observed non-local spin valve signal was further confirmed by the Hanle effect and the spin diffusion length calculated from extracted values for the Cu channel is in agreement with the previously published results. Next, the thickness and temperature-dependent anomalous Hall effect (AHE) and Anomalous Nernst effect (ANE) in a few to bulk 2D vdW ferromagnetic layered material Fe3GeTe2 (FGT) are presented. Large AHE and ANE are observed in few-layer FGT devices exhibiting strong PMA. Characteristics of AHE and ANE suggest that the few-layer FGT flake shows a single domain magnetic structure with nearly square-shaped hall signals and large coercivity, whereas thick (bulk) FGT shows a gradual switching with the magnetic field, indicating the presence of multi-domain structures. Thickness and temperature-dependent Curie temperature (TC) and coercive field (HC) further make it interesting material in vdW ferromagnetic family. Finally, the substrate modulation effect in a p-WSe2/n-WS2 heterojunction diode is presented, where the electric and opto-electric characteristics of the p-n heterojunction diodes on SiO2 and h-BN substrate are studied. The h-BN stands out as an effective substrate compared to the SiO2, showing an overall two times increment in the efficiency of the device. The enhancement in electric and opto-electric properties of the p-n junction diode is mainly attributed to the use of h-BN substrate and the selection of appropriate TMDCs materials and their thicknesses. 2차원 반데르발스(vdW) 층상 물질은 최근 많은 관심을 받고 있으며 전자, 광전자, 스핀트로닉스, 양자소자 등의 분야에서 그 응용 가능성을 보여주고 있다. 이 논문은 금속 및 2차원 반데르발스 층상 물질의 전기적 현상과 스핀트로닉스 현상에 관한 연구와 2차원 물질을 사용한 전자 소자 및 광전소자의 제작에 관한 내용을 포함한다. 첫번째로, 면수직 전류 (CPP)와 면수평 전류(CIP) 구조의 스핀밸브 효과에 대해 논의한다. 면수직 구조에서는 단층 그래핀과 겹층 그래핀을 위쪽 전극과 아래쪽 전극 사이의 층간 물질로 사용한 NiFe/CVD-Gr/Co 소자의 수직스핀밸브(VSV) 효과를 연구하였다. PMMA를 사용하지 않은 건조 전사방법과 전자빔 또는 포토 레지스트를 사용하지 않은 공정을 통하여 자기저항(MR) 에 상당한 향상을 이루었다. 면수평 구조에서는 [CoSiB/Pt]N=7 수직자기 다층박막을 전극으로 사용하여 Cu 채널에 수직스핀분극된 전류를 주입하고 검출하는 수평스핀밸브(LSV) 효과를 연구하였다. 비국소 자기저항값이 기존에 다른 수직자기 전극을 사용한 연구에 비하여 20배 가량 커지는 결과를 얻었다. 측정된 비국소 스핀밸브 신호는 Hanle 효과를 통하여 검증하였으며, 도출된 스핀 확산거리는 기존에 보고된 값들과 잘 맞는 것을 확인하였다. 다음으로, 2차원 반데르발스 강자성 층상 물질인 Fe3GeTe2 (FGT)의 비정상 홀효과와 비정상 네른스트 효과의 두께 의존성와 온도 의존성을 논의한다. 수 층의 FGT에서 큰 비정상 홀효과와 비정상 네른스트 효과가 측정되어 강한 수직자기 특성을 보여주었다. 수 층의 FGT는 단일 자구 특성인 거의 사각 형태의 홀 신호와 매우 큰 보자력을 나타내었다. 반면, 두꺼운 FGT의 경우 점진적인 스위칭 형태의 다중 자구 특성을 보여 주었다. 또한, 두께와 온도에 따른 큐리온도 (TC) 및 보자력 (HC)의 변화는 반데르발스 강자성계 중에서 FGT가 흥미로운 물질임을 보여준다. 마지막으로, p-WSe2/n-WS2 이종접합 다이오드의 전기적 및 광전 특성을 SiO2와 h-BN 기판에서 측정함으로써 기판이 특성에 미치는 영향에 대해 논의한다. h-BN 기판에서 소자의 특성이 2배 정도 향상되는 결과로부터 SiO2에 비하여 더 효과적인 기판이라는 것을 확인하였다.

Achieving genuine social development in Nepal : beyond false MDG target and remittance

SHARMA, DEBENDRA 아주대학교 Graduate School of International Studies Ajo 2016 국내석사

This thesis has two different part I try to connect in one topic. First is that genuine social development and other one is MDG target and remittance. Other hidden part is that instability. These thing try to connect in topic Nepal achieving social development, beyond false MDG target and remittance. First and second chapter I’m writing about the social development and remittance. The MDG target what they reach it is false because to meet their target remittance is the main supporting thing. But it is not durable for country social development, it will be stop one days and country stay in same stage what was before. It means that false MDG target and remittance. In last chapter I write about one case study about the airline in Nepal its represent the development situation in Nepal. Even Airline Corporation couldn’t development itself in 15 year but Nepal’s lots of remote area where the road couldn’t approach until now, airlines helping to develop that region and helping to social development. For that area without airline we couldn’t imagine of social development, airline helping these area by brought foreign and local tourist. Other main thing is that airline corporation supplying the basic need to these area.

(A) PCA-based neural network classifier approach for wireless physical activity monitoring

Sharma, Annapurna Dongseo Univ. 2009 국내석사

Mechanism of Glutamate Release from the Inner Hair Cell of Mammalian Cochlea : 포유동물 와우기관 내유모세포에서의 글루탐산 방출기전

Sharma, Kushal 목포대학교 대학원 2014 국내석사

내유모세포-구심성청신경 간 시냅스는 청각신경계에서의 첫 번째의 시냅스에 해당한다. 내유모세포로부터 신경전달물질의 방출은 음성신호를 전기적신호로 변환시키는데 핵심적인 단계이다. 청각기능에는 유모세포 시냅스의 충실한 소리신호 코딩과정이 반드시 필요하며 이 과정에서 Ca2+의존성 글루탐산 방출이 참여한다. Ca2+채널 활성 변화는 소리신호 코딩과정에 큰 변화를 가져올 수 있다. 내유모세포는 L형 Ca2+채널을 발현하고 있다. 동방결절이나 해마에 있는 L형 Ca2+채널은 cAMP 신호전달과정에 의해 조절된다고 알려져 있다. 내유모세포에 존재하는 L형 Ca2+채널도 cAMP 신호전달과정에 의해 조절될 것이라 가정하였다. Ca2+채널이 cAMP에 의해 조절되는지 확인하기 위해 막투과성 있는 cAMP 유사체인 8-Br-cAMP 존재 하에 내유모세포로부터 패치클램프를 수행하였다. Ca2+전류의 크기 증가뿐만 아니라 채널 개폐의 특성의 증가가 결과로 나타났다. 8-Br-cAMP의 효과는 단백질 키나아제A 억제제에 의해 억제된다. 이는 내유모세포의 L형 Ca2+채널이 cAMP-PKA 신호전달경로에 의해 조절됨을 보여준다. 1. 도파민은 내유모세포 LOC 원심성 신경전달물질 중 하나로써 내유모세포-구심성청신경 간 시냅스에서 신경전달을 억제한다. 내유모세포에서의 글루탐산 방출은 L형 Ca2+채널에 의존하므로 도파민이 L형 Ca2+채널 활성을 억제한다고 가정하였다. 도파민 존재 하에 Ca2+전류 측정을 수행하였다. 도파민은 채널 개폐의 특성 변화 없이 Ca2+흐름을 감소시켰다. 도파민은 cAMP에 의해 활성이 증가된 Ca2+전류 역시 저해하였으며, 아마도 도파민이 cAMP 신호전달경로를 통해 L형 Ca2+채널의 활성을 저해하기 때문으로 생각된다. D2작동제인 quinpirol 또한 내유모세포의 L형 Ca2+채널의 활성을 억제시켰다. 도파민의 작용이 D2수용체를 통해 매개됨을 보여준다. 글루탐산이 방출된 후에는 구심성청신경에서 글루탐산-유발 시냅스 전위를 유발하는데 이 시냅스 전위의 모양이 구심성청신경에 존재하는 K+채널에 의해 조절된다. 그러나 이 시냅스에서의 K+채널의 분자형은 아직 완전히 알려져 있지 않다. electrophysiology 예비실험 결과 값에 의하면 두 가지 서로 다른 K+채널이 밝혀졌다. 이는 고전압 활성 K+채널(HVA K+채널)과 저전압 활성 K+채널(LVA K+채널)이다. 많은 후보군들 중에서 Kv1.1, Kv1.2, Kv7.2, K2p2.1을 선택하여 조사하였다. 다른 청각신경들에 존재하는 LVA K+채널은 Kv1.1, Kv1.2, K2p2.1으로 구성되어있다. Kv3.1b는 HVA K+채널 중 하나로 뇌간의 청각신경에 많이 존재한다. 내유모세포 구심성시냅스의 Kv1.1, Kv1.2, Kv7.2, K2p2.1, Kv3.1b 채널들의 존재는 immunohistochemistry법을 통해 확인하였다. 구심성신경섬유 마커인 α3-Na+,K+ ATPase와 구심성신경섬유와 내유모세포의 마커인 Calretinin의 이중염색을 통하여 세포내 K+채널의 아종류와 발현위치를 확인하였다. Kv1.1, Kv1.2, Kv3.1b의 면역반응이 α3-Na+,K+-ATPase 면역반응성 부위에 나타남을 보여주는 결과는 Kv1.1, Kv1.2, Kv3.1b 채널이 구심성신경섬유의 수상돌기말단과 세포체에 발현됨을 의미한다. 청각이라는 생리학적 현상을 이해하는데 있어서 내유모세포-구심성청신경 간 시냅스의 L형 Ca2+채널과 Kv채널은 매우 중요한 요소라 할 수 있다. Inner hair cell afferent synapses are the first synapse in the auditory nervous system. Release of the neurotransmitter at IHC afferent synapse is the fundamental step of translating the sound signal in to electrical signal. Hearing relies on faithful sound coding at hair cell synapses, which uses Ca2+ triggered glutamate release. Any change on the Ca2+ channel activity can bring a drastic change on the sound coding. Among different types of Ca2+ channel, L-type Ca2+ channel is major type found in the IHC. L-type Ca2+ channel have been found to be modulated by the cAMP signaling pathway in other systems like sinoatrial node and hippocampus. I hypothesized that L-type Ca2+ in IHC will also be modulated by cAMP signaling pathway. To test out whether Ca2+ channel is modulated by cAMP, whole cell patch clamp record on IHCs were done in the presence of the cell permeable cAMP analogue. Result showed that 8-Br-cAMP enhanced the amplitude of Ca2+ current as well as the gating property of the channel. This effect was inhibited by protein kinase A inhibitor. This suggests that L-type Ca2+ channel in IHCs can be modulated by cAMP-PKA pathway. Dopamine is one of the LOC efferent neurotransmitter found to inhibit the synaptic transmission at the IHC afferent synapse. Since IHC glutamate release depends on L-type Ca2+ channel, I hypothesized that L-type Ca2+ current is inhibited by dopamine. Calcium recording was done in the presence of dopamine. Dopamine decreased the amplitude of the Ca2+ current without altering the channel gating properties. It also inhibited cAMP enhanced Ca2+ current suggesting that dopamine may have down regulated the L-type Ca2+ channel activity through cAMP pathway. D2 agonist, quinpirol, also inhibited IHC L-type Ca2+ activity. This suggests that the action was mediated through D2 receptor. After the glutamate release, K+ channel in the auditory afferent nerve fiber modify the shape of the glutamate evoked synaptic potentials. But molecular species of K+ channel are not fully identified in these synapses. The preliminary electrophysiology data, indicated two different K+ channels: low voltage and high voltage activating K+ channels. Among many candidates I chose to investigate Kv1.1, Kv1.2, Kv7.2, K2p2.1, and Kv3.1b. In other auditory neurons LVA K+ channels were often composed of Kv1.1, Kv1.2, Kv7.2, and K2p2.1. Kv3.1b is one of the HVA K+channels to be present in brain stem auditory neurons. To confirm the presence of Kv1.1, Kv1.2, Kv7.2, K2p2.1, and Kv3.1b channel at IHC afferent synapse, I performed immunohistochemistry. Colabelng with α3-Na+,K+-ATPase, (ANF marker) or calretinin, (IHC and ANF marker) was done so that they help cellular identification of K+ subunit expressing site. The results showed that Kv1.1, Kv1.2, and Kv3.1b immunoreactivities were well co-localized with α3-Na+,K+-ATPase immunoreactivities, confirming the expression of Kv1.1, Kv1.2, and Kv3.1b channel at the dendritic terminals and the somas of auditory afferent nerve fibers. L-type Ca2+ channels and Kv channels are very important and critical component in the IHC afferent synapse for understanding the physiology of hearing.

Studies on the regulatory factors affecting bone forming activity of osteoblasts

Sharma, Ashish Ranjan Hallym Univ. 2013 국내박사

Application of ZnO nanowires for intracellular delivery of biomacromolecules and cancer immunotherapy

Sharma, Prahsant 서울대학교 대학원 2019 국내박사

Zinc oxide (ZnO) nanocomposites have been widely applied in biomedical fields due to their multifunctionality and biocompatibility. However, the physicochemical properties of ZnO nanocomposite involved in nano–bio interactions are poorly defined. To assess the potential applicability of ZnO nanowires for intracellular delivery of biomolecules, I examined the dynamics of cellular activity of cells growing on densely packed ZnO nanowire arrays with two different physical conformations, vertical (VNW) or fan-shaped (FNW) nanowires. Although a fraction of human embryonic kidney cells cultured on VNW or FNW underwent rapid apoptosis, peaking at 6 h after incubation, cells could survive and replicate without significant apoptosis on the foreign substrate after 12 h of lag phase. In addition, the cells formed lamellipodia to wrap FNW, and efficiently took up peptides non-covalently coated on VNW and FNW within 30 min of incubation. Moreover, FNW could mediate intracellular delivery of associated DNAs and their gene expression, suggesting that ZnO nanowires transiently penetrate membranes to mediate intra-nuclear delivery of exogenous DNA. These results indicate that ZnO nanowire arrays can serve as nanocomposites for manipulating nano–biointerfaces if appropriately modified in a 3-dimensional conformation. Radially grown ZnO nanowires on poly-L-lactic acid (PLLA) microfibers with the unique 3-dimensional structure were also synthesized and applied as therapeutic cancer vaccines. This inorganic-organic hybrid nanocomposite has mild cellular toxicity but efficiently delivers a tumor antigen into dendritic cells, cellular bridges between innate and adaptive immunity, to stimulate them to express inflammatory cytokines and activation surface markers. I also demonstrated that the hybrid nanocomposites successfully induce tumor antigen-specific cellular immunity and significantly inhibit tumor growth in vivo. ZnO nanowires on PLLA fibers systemically reduced immune suppressive Treg cells and enhanced the infiltration of T cells into tumor tissues, compared to mice immunized with PLLA fibers coated with the antigen. These findings open a new avenue in extending the biomedical application of inorganic metal oxide-inert organic hybrid nanocomposites as a novel vaccine platform. 산화아연(zinc oxide, ZnO) 나노복합체는 다양한 기능과 생체적합성 때문에 의공학 분야에서 광범위하게 사용되고 있다. 그러나 산화아연 나노복합체와 생물학적 시스템 또는 면역체계와의 상호작용 및 그 물리, 화학적 특성은 아직 잘 밝혀지지 않았다. 산화아연 나노선의 의학적 활용가능성을 알아보기 위하여, 본 연구에서는 산화아연 나노선을 커버슬립 위에 수직 형태(vertical nanowire, VNW) 혹은 부채꼴 형태(fan-shaped nanowire, FNW)로 코팅한 후, 그 위에 세포를 배양하여 각각의 세포 활성도의 변화를 측정하였다. VNW 와 FNW 산화아연 나노선에서 배양한 HEK293 세포는 배양 후 6시간까지 세포사멸이 증가하였지만, 그 후 12시간까지는 유의할 만한 세포사멸을 보이지 않으며 생존하였다. FNW에서 자란 세포는 표면을 감싸는 층상위족(lamellipodia)을 형성하였고, 나노선에 결합된 ZBP-FITC를 30분내에 효과적으로 세포내로 섭취하였다. 또한, FNW에 결합한 DNA를 세포 내로 전달하고 세포에서 단백질로 발현되는 것을 확인함으로써, FNW에 의해 외부의 DNA를 핵 내부로 전달할 수 있음을 증명하였다. 이 결과로, 산화아연 나노선 배열이 적절한 3차원 구조를 가진다면 효과적인 나노-바이오 결합체로써 작용할 수 있음을 알 수 있었다. 그에 따라, 폴리젖산 미세섬유에 산화아연 나노선을 방사형으로 자라나게 한 독특한 3차원 구조물을 합성하였고, 치료용 암 백신으로써 산화아연 나노복합체의 항-종양 면역능을 검증하였다. 이 무기물-유기물 하이브리드 나노복합체는 낮은 세포독성을 띠며, 결합된 종양 항원을 효과적으로 수지상세포 안으로 전달하고 세포가 염증성 사이토카인을 발현하게 하여, 선천면역과 적응면역을 연결하는 역할을 하는 것으로 관찰되었다. 이 복합체는 항원-특이적 세포 면역을 효과적으로 유도하며, 종양의 성장을 유의하게 억제하였다. 생체 전반적인 조절 T 세포가 감소하고 종양 조직으로 T 세포의 유입이 증가하였다. 무기물-유기물 하이브리드 나노복합체를 활용하여 항암면역치료에 적용함으로써 새로운 백신 플랫폼으로의 가능성을 보였다.

Boundary estimation with gravitational search algorithm based optimization in electrical impedance tomography

Sharma, Sunam Kumar 제주대학교 대학원 2022 국내박사

Electrical impedance tomography (EIT) is a noninvasive image reconstruction method. It reconstructs the cross-sectional conductivity distribution of the domain. EIT is applied in various areas of applications such as medical, industrial, and geophysical. However, it suffers from poor spatial resolution due to the ill-posed and non-linear nature of the problem. Boundary or shape estimation is the alternative approach to solve this poor resolution problem. In this approach, the number of unknowns to be estimated is reduced which improves the spatial resolution. The conductivity of the closed disjoint region of the domain is assumed to be known as prior for the boundary estimation. In this thesis, for the closed boundary, the complex shape is defined by the Fourier series coefficients and the shape estimation is done with a heuristic algorithm. In this work, we have presented three scenarios for the boundary estimation in EIT. The first study is the estimation of the bladder boundary in the pelvic domain. In this, the boundary is estimated by a heuristic algorithm gravitational search algorithm (GSA). The estimation of the bladder using the noninvasive method is necessary for paraplegia patients. These patients are unable to discharge urine at the right time due to a weaker sensation for bladder volume. If the urine is not discharged in time, then the bladder size will increase and affect the neighboring organs and tissues. Size estimation of the bladder with EIT can clarify the bladder status. The bladder is a nonuniform structure with a complex shape; therefore, higher-order Fourier series is needed to represent the true shape. Estimating higher-order Fourier coefficients by a conventional modified Newton-Raphson (mNR) algorithm does not give the desired performance. GSA is proposed in this work to estimate the Fourier series coefficients as it is known for solving optimization problems in high-dimensional search space. Also, GSA has fast convergence and does not require the computation of Jacobian. Numerical experiments and phantom studies are performed to estimate the bladder size and it is compared with the estimated result by mNR. The second case is the estimation of the defect on the single-layer graphene sheet by PSOGSA. A PSOGSA is a hybrid algorithm that is the combination of particle swarm optimization (PSO) and GSA. Recently, graphene has gained a lot of attention in the electronic industry due to its unique properties and can overcome the limits of miniaturization making way for novel devices in the field of electronics. For the development of new device applications, it is necessary to grow large wafer-sized monolayer graphene. Among the methods to synthesize large graphene films, chemical vapour deposition (CVD) is one of the promising and common techniques but defects such as cracks, holes, or wrinkles are hard to avoid. Electrical impedance tomography (EIT) can be used to detect those defects on a graphene sheet. The conductivity is assumed to be known as prior and the geometry of the defect is estimated. These defect geometries are defined by truncated Fourier series coefficient which can represent the complex shapes. Numerical and experimental studies are done for graphene characterization and the results showed that the proposed PSOGSA has good performance in locating the defects present on a graphene surface. The third is the open boundary case where the interlayer boundary of the subsurface is estimated. Subsurface topology estimation is important for the geophysical survey. The subsurface region can be approximated as piece-wise separate regions with constant conductivity in each region; therefore, the conductivity estimation problem is transformed to estimate the shape and location of the layer boundary interface. Each layer interface boundary is treated as an open boundary that is described using front points. A DNN model is used to estimate the front points describing the multi-layer interface boundaries. This DNN model is tuned for hidden layer nodes using PSOGSA. The PSOGSA tuned DNN model is trained for interlayer boundary reconstruction using training data that consists of pairs of voltage measurements of the subsurface domain. The tuned DNN model estimation result is compared with the 7-layer DNN model. The study on all three cases shows the proposed method has a better estimation result than the compared method.