Efficient plantlet regeneration via somatic embryogenesis and shoot organogenesis in Dichanthium annulatum (Forssk.): a halophyte C4 apomictic forage crop

Shashi,Maity Pooja Jha,Bhat Vishnu 한국식물생명공학회 2023 Plant biotechnology reports Vol.17 No.5

Dichanthium annulatum is a popular halophyte C4 perennial forage crop of semi-arid tropics that reproduces apomictically. In vitro plant regeneration in apomictic species helps in producing new germplasm that can supplement existing breeding program. Field-collected seeds and in vitro shoot apices were tested for response to 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP) for initiation of somatic embryogenesis (SE) and direct shoot organogenesis (DSO). Explants produced callus on Murashige and Skoog (MS) medium with varying level of 2,4-D and 0.5 mgL–1 BAP. After 4th sub-culture, yellowish brown turns into white nodular callus tissue with a friable appearance, which exhibited the highest percentage of embryogenic callus induction on MS medium with 3.0 mgL–1 2,4-D and 0.5 mgL–1 BAP, was transferred to MS with BAP or kinetin and 0.125 mgL–1 2,4-D to promote somatic embryo germination into plantlet. The developmental stages of SE were identified using scanning electron microscopy and histology. Multiple shoots were observed with the combinations of BAP or kinetin with 2,4-D. The highest number of shoots (27) occurred on MS medium comprising 4.0 mgL–1 BAP and 0.125 mgL–1 2,4-D. In vitro plantlet was rooted on MS medium with 0.4% charcoal. The rooted 80% plants could be acclimatized and established in soil, as they showed healthy growth and fertility.

Novel Ensemble Tree for Fast Prediction on Data Streams

Shashi,Priyanka Paygude,Snehal Chaudhary,Debnath Bhattacharyya,Hye-jin Kim 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.8

Data Stream is a continuous set of data records. When data arrive at a very high speed and continuously, so predicting the class in timely manner is important. Class prediction of data Stream is an important task in data mining. Nowadays Ensemble Modeling technique growing rapidly in Data Stream Classification. Ensemble learning become popular because of its advantage to handle large quantity of data stream, means it can handle the data in a bulk and also it can handle concept drifting. Earlier studies, mostly focused on accuracy of ensemble model, prediction efficiency has not considered much because existing ensemble model predicts in linear time, which is enough for general or small applications and existing models works on integrating small number of classifier. But real world application have large volume of data stream so we need more base classifier to identify different patterns and build a high grade ensemble model. To overcome these challenge we propose height balanced tree indexing structure (Ensemble tree) of base classifier for fast prediction on data streams by ensemble modeling technique. Ensemble Tree handles ensembles as spatial databases and it make use of an R-tree like structure to achieve sub linear time complexity.

Numerical Study on Improvement of Detection Accuracy for Wireless Magnetic Motion Capture System

S. Hashi,S. Yabukami,H. Kanetaka,K. Ishiyama,K. I. Arai 한국자기학회 2008 한국자기학회 학술연구발표회 논문개요집 Vol.- No.-

Characterization of Waste Eggshells and CaCO3 Reinforced AA2014 Green Metal Matrix Composites: A Green Approach in the Synthesis of Composites

Shashi Prakash Dwivedi,Satpal Sharma,Raghvendra Kumar Mishra 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.10

Three AA2014 alloy metal matrix composites containing reinforcing particles of eggshell, carbonized eggshell and CaCO3 (powder) were processed. The influences of different particle percentage of eggshell were compared with commercial calcium carbonate. The electromagnetic stir casting technique followed by hot extrusion was employed to fabricate metal matrix composite. The results revealed that the tensile strength, hardness and fatigue strength increased by the addition of eggshell particles up to 12.5 wt.% in AA2014 matrix alloy for both carbonized and uncarbonized reinforced composites. Toughness, ductility and corrosion rate decreased by the addition of eggshell particles up to 12.5 wt.% in AA2014 matrix alloy for both carbonized and uncarbonized reinforced composites. Mechanical properties decreased in the addition CaCO3 in AA2014 matrix alloy. After the heat treatment process, mechanical properties further improved for both carbonized and uncarbonized eggshell particles reinforced composites. However, corrosion rate increased. These results showed that using the carbonized eggshell as reinforcement in the AA2014 alloy gave better physical and mechanical properties at lower cost as compared to uncarbonized ES particles and CaCO3. Apparent interfacial reaction layer and minimum corrosion were observed at AA2014/12.5% carbonized eggshell particulate composite. No reaction product was observed at AA2014/CaCO3 particulate metal matrix composite.

Synthesis and characterization of metal-doped reduced graphene oxide composites, and their application in removal of Escherichia coli, arsenic and 4-nitrophenol

Shashi Prabha Dubey,권영남,Thuy T.M. Nguyen,이창하 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.29 No.-

The aim of the present study is to synthesize dispersible reduced graphene oxide (RGO) viafunctionalization with metals and metal oxides and explore their potential applications in waterpurification. Graphene-based metal and metal oxide composites were synthesized hydrothermally usingsodium borohydride as a reducing agent and sodium sorbate as a stabilizer. Single (Ag, Cu2O, and Fe3O4)and bimetallic (Ag-Cu2O, Ag-Fe3O4, and Cu2O-Fe3O4) nanoparticles were incorporated on the surface ofRGO. The synthesized composites were characterized by various analytical methods. The inactivation ofE. coli, the catalytic degradation of 4-nitrophenol, and the adsorption of As(V) were examined using theRGO composites.

Resource Allocation Strategy for Latency Sensitive IoT Traffic

Shashi Raj Pandey,Sabah Suhail,Yan Kyaw Tun,Choong Seon Hong 한국정보과학회 2018 한국정보과학회 학술발표논문집 Vol.2018 No.6

The Land of the Better Story

Shashi Tharoor 동아시아재단 2007 Global Asia Vol.2 No.1

교양 문학 수업 사례 연구- 피드백 기반 조별 발표가 탐구공동체(CoI)에 미치는 영향

Shashi Kumar Mishra,박정이,김도훈 한국교양교육학회 2017 교양교육연구 Vol.11 No.4

This study compares instructor-led literature teaching method with student presentation-based learning method to explore effective design and implementation of the latter, which replaces the instructor’s lecture with student presentation to engage students in the learning process. The theoretical and analytical framework for this study is the community of inquiry, whose basic concept was first introduced by early pragmatists Charles Sanders Peirce and John Dewey. It posits that ideal learning takes place when three essential presences―teaching, social, and cognitive―are firmly in place. First, teaching presence is the instructor’s orchestration of content, activities, and assessments. Second, social presence is the atmosphere where students are empowered to participate in the community of inquiry. Third, cognitive presence is the extent to which students construct and confirm knowledge through critical thinking and reflection. With regard to the analysis, this study employs the community of inquiry instrument to measure the perceptions of 26 students who attended the “Arche Seminar: World Literature” class in the fall 2016 semester. The perception differences for the three presences are investigated, followed by a detailed analysis of individual survey items. 학습자 중심 교육이 필요하다는 인식에도 불구하고 대학의 교양 문학 수업에서는 교수자가 주도하는 강의 중심 교수법이 일반적으로 사용되고 있다. 주로 전공이 서로 다른 저학년 학생들이고 수강생도 많다 보니 다양한 협동 활동을 진행하기 힘든 면도 있다. 협동학습을 도입해 교수자 강의를 학생들의 조별 발표로 대체하려고 해도 이를 교수 태만으로 연결시키는 분위기도 있어 교수자는 그저 ‘열심히’ 강의를 한다. 이에 본 연구에서는 교수자 강의중심 교수법과 조별 발표중심 교수법에 대한 학생들의 탐구공동체 인식을 비교하고 개선점을 정리했다. 조별 발표중심 교수법의 경우 교수자의 강의를 상당 부분 학생들의 발표로 대체했지만 사전 피드백을 통해 수업 내용의 왜곡이나 손실을 최소화하려 노력했으며 궁극적으로는 탐구공동체를 활성화시키고자 했다. 탐구공동체란 공동의 탐구 문제를 공유하며 해결책을 모색하기 위해 모인 집단을 일컫는 개념으로 교수적 실재감, 사회적 실재감, 인지적 실재감을 통해 활성화된다. 교수적 실재감은 수업 내용과 관련한 설명, 학습 활동 지도, 평가 등 제반 설계 및 운영에 있어서의 교수자의 조율 능력이다. 사회적 실재감은 구성원들이 자발적으로 탐구공동체의 일원으로서 느끼고 생각하며 행동하는 정도를 가리킨다. 인지적 실재감은 다변량 척도로서 비판적 사고와 건설적 상호작용, 성찰을 통해 달성되는 지식 축적 및 활용 능력이다. 수업 사례 분석에 있어서는 탐구공동체 설문을 통해 부산외국어대학교 교양대학에서 2016년 진행된 <아르케 세미나 - 세계문학> 수강생 26명의 교수법 전환에 따른 인식 변화를 비교하고 분석했다. 교수자 강의중심 교수법에서 조별 발표중심 교수법으로 전환한 후 탐구공동체의 3가지 영역에 대해 모두 긍정적인 인식 변화가 학생들에서 일어났다. 교수적 실재감에 있어서는 조별 발표중심 교수법에서도 교수자의 역할이 줄어들지 않았고 사회적 실재감에 있어서는 조별 발표중심 교수법을 통해 학생들이 탐구공동체 일원이 되었다고 인식했으며 인지적 실재감에 있어서는 자료 검색 및 활용 출처가 확대되고 지식이 확산되었다.

Q-learning Supplemented Crowdsensing Framework for Resource Constrained Devices

Shashi Raj Pandey,Sabah Suhail,Choong Seon Hong 한국정보과학회 2017 한국정보과학회 학술발표논문집 Vol.2017 No.12

Effect of MgO addition on physico-chemical, mechanical and thermal behaviour of Al/Si3N4 composite material developed via hybrid casting technique

Shashi Prakash Dwivedi,Ashok Kumar Mishra,V. R. Mishra 한양대학교 세라믹연구소 2019 Journal of Ceramic Processing Research Vol.20 No.6

In the present investigation, aluminium based composite material developed by using Si3N4 as primary reinforcement material and MgO as secondary reinforcement material by hybrid casting techniques. The microstructure of composite developed by hybrid casting technique showed a uniform distribution of Si3N4 and MgO particles in the AA2024 aluminium alloy. Maximum tensile strength and hardness were found to be 214.5 MPa and 78 BHN for heat-treated AA2024/7.5% Si3N4/5% MgO composite material. Minimum thermal expansion was also found for AA2024/7.5% Si3N4/5% MgO composite material. However, minimum corrosion loss was found for AA2024/10% Si3N4/2.5% MgO composite material. Though, toughness and ductility were reduced by adding the Si3N4 and MgO particles in AA2024 aluminium alloy. XRD analysis of AA2024/7.5% Si3N4/5% MgO composite material was also observed to see the effect of Si3N4 and MgO particles addition in AA2024 aluminium alloy.