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Equivariant Cobordism of Torus Orbifolds

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Chinese Annals of Mathematics,Series B 2021年第6期42卷 861-890页

作者： Soumen sarkar DongYoup SUH Department of Mathematics Indian Institute of Technology MadrasChennai 600036India Department of Mathematical Sciences KAISTDaejeon 305701Republic of Korea

Torus orbifolds are topological generalizations of symplectic toric *** authours give a construction of smooth orbifolds with torus actions whose boundary is a disjoint union of torus orbifolds using a toric topological *** a result,they show that any orientable locally standard torus orbifold is equivariantly cobordant to some copies of orbifold complex projective *** also discuss some further equivariant cobordism results including the cases when torus orbifolds are actually torus manifolds.

关键词： Manifold with corners Torus action Torus orbifolds Equivariant cobordism

On Universality of Quantum Fourier Transform

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Chinese Physics Letters 2012年第3期29卷 17-20页

作者： Arpita Maitra Santanu sarkar Applied Statistics Unit Indian Statistical Institute203 B T RoadKolkata 700108India

A methodology is presented to obtain the basis of qudits which are admissible to quantum Fourier transform(QFT)in the sense that the set of such kets are related by the QFT in the same way as the kets of the computational *** first study this method for qubits to characterize the ensemble that works for the Hadamard transformation(QFT for two dimension).In this regard we identify certain incompleteness in the result of Maitra and Parashar(*** Inform.4(2006)653).Next we characterize the ensemble of qutrits for which QFT is ***,some theoretical results related to higher dimensions are also *** the unitary matrix Un related to QFT,the issue boils down to the problem of characterizing matrices that commute with Un.

关键词： ensemble admissible dimensions

Ancient rip current records and their implications: an example from the Cretaceous Ukra Member, Kutch, India

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Journal of Palaeogeography 2020年第2期9卷 181-197页

作者： Subir sarkar Amlan Koner Department of Geological Sciences Jadavpur UniversityKolkata 700032India

Poorly-sorted conglomerate patches rich in granules or sturdy fossils or both, and reddish mud matrix within the interstices stand out amidst fine-grained siliciclastic shelf sediments of the trangressive systems tract(TST) of the Lower Cretaceous Ukra Member, Kutch Basin, India. The siliciclastic shelf sediments contrast the conglomerates with their remarkable lateral extension. The fossils belong to a low-diversity group of sedentary bivalves that can be traced into the shoreface facies assemblage. The shelf sandstones are almost always sculpted by wave structures,especially hummocky cross-stratification while textures in the conglomerates suggest that the sediment settling was generally from suspensions. Textural variations in conglomerates reflect an immediate variation in flow viscosity prior to the downloading. The current structures obtained from the conglomerates record offshoreward palaeocurrent, in contrast to the shore-parallel palaeocurrent in the TST. The hummocky cross-stratified(HCS) beds are interpreted as seasonal storm deposits, while the conglomerate patches are taken as rip current deposits induced by waves of much longer periods. The glauconite-rich shale that alternates with conglomerates is probable fair-weather products. The conglomerates could not be recognized either in the coarse-grained shoreface deposits occupying the lower part of the overall fining-upward TST or in the coarsening-upward and glauconite-depleted highstand systems tract(HST). In contrast to the TST, the HST is dominantly tide-imprinted, having shore-normal palaeocurrent direction. It appears that intensification of waves and weakening of tides during transgression favored strong rip currents generation, which had presumably caused severe damage to the sea coast and to the shell banks growing preferably at the necks of the rip current channels. Rapid lateral facies transitions in the shoreface deposits at the basal part of the TST suggest enhanced irregularity in the coast

关键词： Rip current fan Ukra Member TST shelf Longshore current Shore-normal flux Mass flow deposits Global warming Ukra Sea

Optimization and application of UVC irradiation for prevention of fungal biodeterioration of vegetable tanned and chrome tanned leather

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Journal of Leather Science and Engineering 2022年第2期4卷 380-393页

作者： Eshita Jhahan Subarna Bhattacharyya Anirban Chaudhuri Nirmal sarkar Shaheen Akhtar Punarbasu Chaudhuri School of Environmental Studies Jadavpur UniversityKolkata 700032India Department of Environmental Science University of CalcuttaKolkataIndia.

UV-C irradiation critically effects the growth of micro-fungi and also deteriorate leather materials. In the present study vegetable tanned and chrome tanned leather were infected with pure cultures of Aspergillus niger and Aspergillus flavus, which were isolated from stored leather materials. UV-C light (λ = 254 nm) was applied on infected leather for 15 and 60 min. The changes in leather qualities were examined through weight, tensile strength, scanning electron microscope, energy dispersive X-ray and Fourier transform infrared spectroscopy study after 15 and 30 days of fungal inoculation. Vegetable tanned leather was more vulnerable in case of fungal attack than chrome tanned leather while A. flavus showed more influence on leather deterioration than A. niger. The results showed that weight loss after 30 days for 15 and 60 min irradiation exposure was 1.3% compared to A. flavus infected leather (3.93%). The tensile strength of vegetable and chrome tanned UV irradiated leather was increased by 44% and 7% respectively. The scanning electron microscopic images exhibit the limited presence of conidiophores in UV-C exposed leather which confirmed the potentiality of irradiation for controlling fungal growth. The infrared spectral analysis of UV-C exposed infected leather samples showed neither shifting of wavenumber nor displacement of any functional groups. Alto-gether the efficacy of UV-C irradiation against biodeterioration of leather was concluded to be effective. This method can be used to control fungal growth without compromising the leather quality.

关键词： Aspergillus Biodeterioration Leather SEM Tensile strength UV-C

Les BRICS l'emportent sur les blocs Une approche pragmatique favorise une collaboration fructueuse

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中国与非洲（法文版） 2022年第8期14卷 46-48页

作者： SUDESHNA sarkar 不详

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In Good Spirits

China Today 2022年第4期71卷 58-59页

作者： SUDESHNA sarkar 不详

Australia’s loss of the China wine market has been South Africa’s *** can it be sustained?AROUND the time the Chinese celebrate the Spring Festival,a time of family reunions and feasting,South Africa celebrates the birth of its wine *** is a happy serendipity as the South African wine industry has found a rising market in China,and the Spring Festival is the time when it surges higher *** February 2,South African vintners raised a toast for the 363rd birthday of their wine industry,the only one in the world to have an official historical birthday for the *** record of the first wine made in South Africa is found in the diary of Johan Anthoniszoon van Riebeeck,an employee of the Dutch East India Company,who arrived in 1652 to take up his post.

关键词： union Dutch sustained

L'ivresse du succès La perte du marché chinois du vin par l'Australie a profité à l'Afrique du Sud. Mais est-ce durable?

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中国与非洲（法文版） 2022年第4期14卷 50-51页

作者： SUDESHNA sarkar 不详

Unified Smith Predictor Based H_∞ Wide-Area Damping Controller to Improve the Control Resiliency to Communication Failure

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 584-596页

作者： Mithu sarkar Bidyadhar Subudhi Sandip Ghosh G H Raisoni College of Engineering Nagpur 440016India Indian Institute of Technology Goa-403401India Indian Institute of Technology Banaras Hindu University(BHU)Varanasi 221005India

Inter-area low frequency oscillation in power system is one of the major problems for bulk power transmission through weak tie *** of wide-area signal is more effective than the local area signal in damping out the inter-area *** area measurement system(WAMS)is convenient to transmit the wide area signal through the communication channel to the remote *** failure is one of the disastrous phenomena in a communication *** this paper,a dual input single output(DISO)Hm controller is designed to build the control resiliency by employing two highest observability ranking wide area signals with respect to the critical damping inter-area *** proposed controller can provide sufficient damping to the system and also the system remains stabilized if one of the wide-area signals is *** time delay is an unwanted phenomenon that degrades the performance of the *** unified Smith predictor approach is used to design a Hm controller to handle the time ***'s two-area and IEEE-39 bus test systems are considered to verify the effectiveness of the proposed *** the simulation results,it is verified that,the proposed controller provides excellent damping performance at normal communication and improves the controller resiliency to counteract the communication failure.

关键词： Communication failure dual input single output(DISO)controller H_∞control inter-area oscillation unified Smith predictor

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A Tone-Deaf Approach

China Today 2022年第5期71卷 45-47页

作者： SUDESHNA sarkar 不详

Why the EU-China Summit failed to meet the EU’s expectation...and so would other such talks.T was both extraordinary and incredible to hear EU High Representative for Foreign Affairs and Security Policy Josep Borell,who along with European Council President Charles Michel and European Commission President Ursula von der Leyen took part in the 23rd EU-China Summit on April 1,describe the meeting as"a dialogue of the deaf."No doubt from the European Union’s point of view the dialogue with Chinese President Xi Jinpingand Premier Li Keqiang was fruitless and unsatisfactory but to equate lack of results to communication with the hearing impaired smacks of a medieval mindset not expected from its top *** this is the language of diplomacy,then no wonder the EU has been so singularly inept at negotiating a peaceful resolution to the Ukraine crisis.

关键词： Borel expectation impaired