• Title/Summary/Keyword: Quantum transformation

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Canonical Transformations for Time-Dependent Harmonic Oscillators

  • Park, Tae-Jun
    • Bulletin of the Korean Chemical Society
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    • 제25권2호
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    • pp.285-288
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    • 2004
  • A canonical transformation changes variables such as coordinates and momenta to new variables preserving either the Poisson bracket or the commutation relations depending on whether the problem is classical or quantal respectively. Classically canonical transformations are well established as a powerful tool for solving differential equations. Quantum canonical transformations have been defined and used relatively recently because of the non-commutativeness of the quantum variables. Three elementary canonical transformations and their composite transformations have quantum implementations. Quantum canonical transformations have been mostly used in time-independent Schrodinger equations and a harmonic oscillator with time-dependent angular frequency is probably the only time-dependent problem solved by these transformations. In this work, we apply quantum canonical transformations to a harmonic oscillator in which both angular frequency and equilibrium position are time-dependent.

The Lecomte-Ueda Transformation and Resonance Structure in the Multichannel Quantum Defect Theory for the Two Open and One Closed Channel System

  • Lee, Chun-Woo;Kim, Ji-Hyun
    • Bulletin of the Korean Chemical Society
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    • 제23권11호
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    • pp.1560-1567
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    • 2002
  • The transformation devised by Lecomte and Ueda for the study of resonance structures in the multichannel quantum defect theory (MQDT) is used to analyze partial photofragmentation cross section formulas in MQDT analogous to Fano's resonance formula obtained in the previous work for the system involving two open and one closed channels. Detailed comparison of the MQDT results with the configuration mixing (CM) ones is made. Resonance structures and their geometrical relations in the MQDT formulation are revealed and classified by combining Lecomte and Ueda's theory with the geometrical method devised to study the coupling between background and resonance scatterings.

전력전자 사상(思想) : 전자변압기 및 페이저변환 (The Most Fundamental Principles of Power Electronics : "Electronic transformer & Phasor Transformation")

  • 임춘택
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2010년도 하계학술대회 논문집
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    • pp.436-437
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    • 2010
  • 전력전자공학의 목적은 전자적인 스위치를 이용하여 전력을 원하는 대로 변환하는 것이다. 전력전자시스템을 제어하려면 스위치 동작과 교류회로의 동적특성을 이해해야 한다. 본 논문에서는 전력전자의 핵심이 되는 기술사상(技術思想)을 다음 2가지로 정리하였다. 1) 모든 전자 스위치는 등가적으로 정확히 시변 선형 또는 비선형 전자변압기다. 2) 모든 교류회로의 정적 또는 동적 특성은 페이저변환으로 해석가능하다. 이번 논문에서 일반화된 전자변압기 모델을 제시하고, 단상 및 다상을 통합하고 D-Q회로변환과 양자회로변환(quantum circuit transformation)을 모두 포용하는 일반화된 페이저변환을 제시한다.

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RIGHT RÉNYI MEAN AND TENSOR PRODUCT

  • HWANG, JINMI;JEONG, MIRAN;KIM, SEJONG
    • Journal of applied mathematics & informatics
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    • 제39권5_6호
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    • pp.751-760
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    • 2021
  • We study in this paper the right Rényi mean for a quantum divergence induced from the α - z Rényi relative entropy. Many properties including homogeneity, invariance under permutation, repetition and unitary congruence transformation, and determinantal inequality have been presented. Moreover, we give the identity of two right Rényi means with respect to tensor product.

양자 기법 기반 증강현실 객체 간 생태계 변형 (Quantum Inspired Eco-system Transformation in Augmented Reality)

  • 김주환;조동식
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2019년도 춘계학술대회
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    • pp.573-575
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    • 2019
  • 최근, 증강현실(AR) 기술은 국방, 의료, 교육, 엔터테인먼트 등 다양한 분야에서 널리 이용되고 있고, 증강현실 환경에서 사용자는 가상의 객체를 생성할 수 있을 뿐 아니라 가상 객체와 사용자 간의 상호작용도 가능하다. 이러한 증강현실 분야에서는 사용자의 특정 행동에 대한 미리 지정된 가상 객체의 반응에 대한 상호작용 모델에 대한 연구가 주로 이루어지고 있다. 인공지능과 결합된 미래의 증강현실 환경을 생성 및 상호작용을 위해서는 생성된 가상의 객체 간 자동적으로 상호작용하는 모델에 대한 기법이 필요한 상황이다. 본 논문에서는 양자 컴퓨팅에서 사용자하고 있는 양자 얽힘, 중첩 현상을 기반으로 하여 증강현실 환경에서 가상의 객체에 대한 상호작용 모델을 제시하고자 한다. 예를 들면, 증강현실 사용자의 의해 즉각적으로 생성된 객체가 기존 객체들과의 어떻게 상호작용 할 수 있고, 각각의 객체의 특성으로 인한 객체수의 증가 및 감소가 사용자의 개입 없이 자동으로 이루어지도록 양자 얽힘과 중첩을 기반으로 한 기법을 제시하고자 한다. 이를 위해 본 연구에서는 숲과 관련된 생태계 환경을 증강현실 환경으로 조성하여 가상의 동물들 간 자동으로 변형되는 콘텐츠를 구현하고자 한다.

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Consciousness, Cognition and Neural Networks in the Brain: Advances and Perspectives in Neuroscience

  • Muhammad Saleem;Muhammad Hamid
    • International Journal of Computer Science & Network Security
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    • 제23권2호
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    • pp.47-54
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    • 2023
  • This article reviews recent advances and perspectives in neuroscience related to consciousness, cognition, and neural networks in the brain. The neural mechanisms underlying cognitive processes, such as perception, attention, memory, and decision-making, are explored. The article also examines how these processes give rise to our experience of consciousness. The implications of these findings for our understanding of the brain and its functions are presented, as well as potential applications of this knowledge in fields such as medicine, psychology, and artificial intelligence. Additionally, the article explores the concept of a quantum viewpoint concerning consciousness, cognition, and creativity and how incorporating DNA as a key element could reconcile classical and quantum perspectives on human behaviour, consciousness, and cognition, as explained by genomic psychological theory. Furthermore, the article explains how the human brain processes external stimuli through the sensory nervous system and how it can be simulated using an artificial neural network (ANN) consisting of one input layer, multiple hidden layers, and an output layer. The law of learning is also discussed, explaining how ANNs work and how the modification of weight values affects the output and input values. The article concludes with a discussion of future research directions in this field, highlighting the potential for further discoveries and advancements in our understanding of the brain and its functions.

QNFT: A Post-Quantum Non-fungible Tokens for Secure Metaverse Environment

  • Abir El Azzaoui;JaeSoo Kim
    • Journal of Information Processing Systems
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    • 제20권2호
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    • pp.273-283
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    • 2024
  • The digital domain has witnessed unprecedented growth, reshaping the way we interact, work, and even perceive reality. The internet has evolved into a vast ecosystem of interconnected virtual worlds, giving birth to the concept of the Metaverse. The Metaverse, often envisioned as a collective virtual shared space, is created by the convergence of virtually enhanced physical reality and interactive digital spaces. Within this Metaverse space, the concept of ownership, identity, and authenticity takes on new dimensions, necessitating innovative solutions to safeguard individual rights. The digital transformation through Metaverse has also brought forth challenges, especially in copyright protection. As the lines between the virtual and physical blur, the traditional notions of ownership and rights are being tested. The Metaverse, with its multitude of user-generated content, poses unique challenges. The primary objective of this research is multifaceted. Firstly, there's a pressing need to understand the strategies employed by non-fungible token (NFT) marketplaces within the Metaverse to strengthen security and prevent copyright violations. As these platforms become centers for digital transactions, ensuring the authenticity and security of each trade becomes paramount. Secondly, the study aims to delve deep into the foundational technologies underpinning NFTs, from the workings of blockchain to the mechanics of smart contracts, to understand how they collectively ensure copyright protection. Thus, in this paper, we propose a quantum based NFT solution that can secure Metaverse and copyright contents in an advanced manner.

Characterization of Metakaolinite with Multiple Quantum MAS NMR

  • Han, Oc-Hee;Stefan Steuernagel
    • 한국자기공명학회논문지
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    • 제4권1호
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    • pp.12-18
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    • 2000
  • Metakaolinite produced by thermal transformation from kaolinite was studied by 27Al multiple quantum magic angel spinning (MQMAS) NMR technique in addition to 1-dimensional 27Al and 29Si MAS NMR. Our results confirm that 4-, 5-, 6- coordinated aluminum sites co-exit with some distribution of isotropic chemical shifts. This is consistent with amorphous character of metakaolinite observed with X-ray diffraction. In addition, characterization with MQMAS is briefly discussed in comparison with other NMR techniques to identify different aluminum sites especially when peaks are severely overlapped in 1-dimensional 27Al MAS NMR spectra.

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Multichannel Quantum Defect Study of the Perturber's Effect on the Overlapping Resonances in Rydberg Series for the Systems Involving 2 Closed and Many Open Channels

  • Lee, Chun-Woo
    • Bulletin of the Korean Chemical Society
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    • 제31권6호
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    • pp.1669-1680
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    • 2010
  • The phase-shifted version of the multichannel quantum-defect theory (MQDT) was reformulated by disentangling the interloper spectrum from the perturbed dense Rydberg series for a systems involving 2 closed and more than 1 open channel. The theory was applied successfully to Martins and Zimmermann's photoionization spectra of the Rydberg series Cu I $3d^9\;4s(^1D_2)\;nd^2G_{9/2}$ perturbed by the interloper, $3d^9\;4p^2\;^4F_{9/2}$, for which Cohen's 4 channel QDT had failed. The zero surface graphic of the perturbed Fano's asymmetry parameter q of the autoionization spectrum of dense Rydberg series by the interloper was determined by only two parameters for this system. It was used as a map to trace the transformation route of the 3 channel autoionization spectra to the 4 channel spectra when the channel coupling of the closed channels with a newly added open channel was turned on progressively.

PHOTOCHEMICAL TRANSFORMATION OF CARBON MONOXIDE IN AQUEOUS AMMONIA

  • Kim, Hee-Jeong;Park, Hyoung-Ryun
    • Journal of Photoscience
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    • 제6권4호
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    • pp.177-181
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    • 1999
  • The photochemical transformation of carbon monoxide in aqueous ammonia solution has been investigated at 25${\pm}$0.1$^{\circ}C$ using 184.9 nm UV light. Amination and carbonylation processes were carried out by irradiating the aqueous ammonia solution saturated with carbon monoxide, and the formation of formamide, urea, hexamethylenetetramine, formaldehyde, glyoxal and hydrazine was observed. The formation of hydrazine was affected by the presence of ammonia, and the formation of carbonyl compounds such as formaldehyde and glyoxal was influenced by the presence of carbon monoxide. The formation of formamide, urea and hexamethylenetetramine was affected by both ammonia and carbon monoxide. The initial quantum yields of the products were determined and probable mechanisms for the photochemical reaction were presented on the basis of product analysis.

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