• Title/Summary/Keyword: Self-interference

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Coherence Studies of Photons Emitted from a Single Terrylene Molecule Using Michelson and Young’s Interferometers

  • Yoon, Seung-Jin;Trinh, Cong Tai;Lee, Kwang-Geol
    • Journal of the Optical Society of Korea
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    • v.19 no.6
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    • pp.555-559
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    • 2015
  • Coherence length (time) is a key parameter in many classical and quantum optical applications. Two interferometers – Michelson and Young’s double-slit – are used to characterize the temporal coherence of single photons emitted from single terrylene molecules. For quantitative analysis, a dispersion-related distortion in the interference pattern of a Michelson interferometer is carefully corrected by a simple dispersion compensation. Additionally, it has been demonstrated that Young’s interferometer can be used in temporal coherence studies at the single photon level with high accuracy. The pros and cons of the two systems are discussed. The measured coherence lengths in the two systems are consistent with one another under the self-interference interpretations.

A Study on the Adaptive Active Noise Control Using the Self-tuning feedback controller (자기동조 피이드백 제어기를 이용한 적응 능동소음제어에 관한 연구)

  • Shin, Joon;Lee, Tae-Yeon;Kim, Heung-Seob;Jo, Seong-Oh;Bang, Seung-Hyun;Oh, Jae-Eung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1993.04a
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    • pp.140-146
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    • 1993
  • Active noise control uses the intentional superposition of acoustic waves to create a destructive interference pattern such that a reduction of the unwanted sound occurs. In active noise control system the choice of a control structure and design of the controller are the main issues of concern. In real acoustic fields there are a vast number of noise sources with time-varying nature and the characteristics of transducers and the geometric set-up of control system are subject to change. Accordingly the control system should be designed to adapt such circumstances so that required level of performance is maintained. In this paper, the adaptive control algorithm for self-tuning adaptive controller is presented for the application in active noise control system. Self-tuning is a direct integration of identification and controller design algorithm in such a manner that the two processes proceed sequentially. The least mean square algorithm was used for the identification schemes and adaptive weighted minimum variance control algorithm was applied for self-tuning controller. Computer simulation results for self-tuning feedback controller are presented. And simulation results was shown to be useful for the situation in which the periodic noise sources act on the acoustic field.

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A Study on Sense of Self-efficacy and Stress Encountering Strategy of Smart-phone Addicted University Students (스마트폰중독 대학생의 자기효능감과 스트레스 대처전략에 관한 연구)

  • Baek, Yumi
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.13 no.1
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    • pp.173-183
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    • 2017
  • The purpose of this study is to find out the difference of sense of self-efficacy and stress encountering strategy of university students under the stress situation depending on the smart-phone user group (addiction group, general user group). For this purpose, the study issues are established as follows. First, it has analyzed what is the correlation of smart-phone addiction, sense of self-efficacy, and stress encountering strategy. Second, it has studied if there is any difference of sense of self-efficacy and stress encountering strategy for the smart-phone user group. In order to verify such study issues, For 1,670 university students in the Chungcheong area, smart-phone addiction scale, sense of self-efficacy scale, and stress encountering method scale were administered. Looking into the study result, first, as a result of the relativity analysis, it displayed the correlation of preference of test difficulty, self-control efficacy and important negative from the smart-phone addiction and sense of self-efficacy. In addition, all sub-variables of smart-phone addiction and avoidance orientation from the stress encountering strategy displayed the important positive correlation, and from the smart-phone addiction, the virtual world orientation and pursuit of social-support displayed the important negative correlations, and all sub-variables (interference with ordinary living, virtual world striving direction, withdrawal, resistance) of smart-phone addiction and problem solving-orientation displayed the negative correlation. Second, as a result of verification for the difference of the smart-phone addiction group and general use group following the sense of self-efficacy, the general use group is shown to have higher self-control efficacy sense than the addiction group. And third, as a result of verifying the difference of stress encountering following the smart-phone addiction group and general use group, the addiction group is shown to be lower than the general use group in terms of social support pursuit and problem solution orientation with the avoidance orientation shown to be higher. This type of result is expected to provide the base data when developing the smart-phone addiction preventive education program by finding out in details for the characteristics of smart-phone addiction group for university students.

Differential Interference Contrast Microscopic Module Using a Polarization Grating for Quantitative Phase Imaging (편광 격자 기반 정량적 위상 이미징을 위한 미분 간섭 현미경 모듈 개발)

  • Jin Hee Cho;Ki-Nam Joo
    • Korean Journal of Optics and Photonics
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    • v.34 no.6
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    • pp.261-268
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    • 2023
  • We propose a compact differential interference contrast microscopic module, which enables snapshot measurements for quantitative phase imaging. The proposed module adopts the lateral shearing interferometric principle, which can obtain self-interference without a reference. Due to the absence of the reference, the system is more stable than the typical interferometric systems. It uses a polarization grating to generate two laterally shifted wavefronts based on its birefringence and polarizing beam-splitting characteristics. Furthermore, the use of a polarization camera does not require sequential measurements for the phase extraction. In the experiments, we observe and measure the timely varying changes of various specimens to verify the system performance with the bright field images and phase contrast images. Because the proposed microscopic module also has the merit of being adaptable to typical microscopy instead of using an imaging camera, it can conveniently replace conventional contrast microscopy.

Expectations of Middle aged Women for a life of Happiness to the Spouse (중년여성이 행복한 삶을 위해 배우자에게 기대하는 행동유형에 관한 연구)

  • Sim, In Ok
    • Women's Health Nursing
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    • v.21 no.2
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    • pp.139-149
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    • 2015
  • Purpose: This study was to define and analyze the expectations of middle-aged woman to their spouse. Methods: A sample of 39 middle-aged women was recruited from the workplace, religious organization and acquaintances. The survey was conducted with participants using self-reported questionnaire. The data were analyzed using Q methodology. Results: There were four different types of expectations of middle-aged women. First type was "Collaborative and self-development type," meaning that women developed self and were collaborated with their family or spouses. The second type was "Maintain their own life" meaning that women recognized and maintained their expertise without interference from their spouses. The third one was "Respect for the inner value" meaning that women gave continued respect and understanding their inner value. The last one was "Realistic acceptance" meaning that women kept the current situation without implementing new self-development type. Conclusion: There is a subjective structure within the types of expectations of middle-aged women for a life of happiness to the spouse.

Management of Neighbor Cell Lists and Physical Cell Identifiers in Self-Organizing Heterogeneous Networks

  • Lim, Jae-Chan;Hong, Dae-Hyoung
    • Journal of Communications and Networks
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    • v.13 no.4
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    • pp.367-376
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    • 2011
  • In this paper, we propose self-organizing schemes for the initial configuration of the neighbor cell list (NCL), maintenance of the NCL, and physical cell identifier (PCI) allocation in heterogeneous networks such as long term evolution systems where lower transmission power nodes are additionally deployed in macrocell networks. Accurate NCL maintenance is required for efficient PCI allocation and for avoiding handover delay and redundantly increased system overhead. Proposed self-organizing schemes for the initial NCL configuration and PCI allocation are based on evolved universal terrestrial radio access network NodeB (eNB) scanning that measures reference signal to interference and noise ratio and reference symbol received power, respectively, transmitted from adjacent eNBs. On the other hand, the maintenance of the NCL is managed by adding or removing cells based on periodic user equipment measurements. We provide performance analysis of the proposed schemes under various scenarios in the respects of NCL detection probability, NCL false alarm rate, handover delay area ratio, PCI conflict ratio, etc.

Effect of Self-Regulatory Focus on Purchase Intentions of Foreign-owned Perceived Local Brands

  • Xi LIU
    • The Journal of Industrial Distribution & Business
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    • v.14 no.4
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    • pp.1-10
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    • 2023
  • Purpose: This paper aims to investigate how self-regulatory focus (SRF) influences the relationship between perceived brand localness (PBL) and purchase intentions (PI). This research adopted both domestic and foreign-owned brands to examine the moderating effect of self-regulatory orientations and product types respectively to exclude the interference of brand origin. Research design, data, and methodology: This study surveyed Chinese consumers and collected data using social media applications. ANOVA analysis and PROCESS modeling were adopted to complete the empirical analysis. Results: This research demonstrates that brand origin does not inhibit the positive impact of PBL on purchase intentions regardless of whether it originates from mainland China or not. Study 1 proved that the effect of PBL on PI is more convincing among consumers with promotion focus orientations. In study 2, higher purchase intentions were found for hedonic perceived local brands among promotion-focused consumers while significant preferences were found for utilitarian perceived local brands among prevention-focused consumers. Conclusions: This research complements the literature about the potential psychological factors influencing PBL and contributes to marketers in developing effective marketing strategies and appropriate positioning decisions. Overall, this study has important theoretical and managerial contributions to international marketing, particularly in the context of the current recession.

Adaptive array processing (적응 어레이 프로세싱)

  • 이상철
    • 전기의세계
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    • v.29 no.9
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    • pp.584-593
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    • 1980
  • Conventional radar antenna systems are susceptible to performance degradation caused by unwanted signals received via the antenna sidelobes and/or mainlobes. Adaptive array systems offer possible solution to this interference problem by automatically steering nulls to unwanted signals providing significant system performance improvement. Another important andvantage of the adaptive array is its self-optimization capability which uses the collective incoming noise data for the nulling purposes. This paper provides a tutorial introduction to adaptive arrays as well as some new development of recent research in this area. Optimum link between the antenna theory and signal processing has been sought by illustrating the gain patterns and output signal-to-noise ratio. Signal acqusition methods are shown including a new attempt of the use of spread-spectrum techniques in conjuction with array systems.

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Sinusoidal Interference Rejection by Self-Tuning Method (자기 동조법에 의한 정현파 간섭음 제거)

  • 유흥균;염동홍;안수길
    • The Journal of the Acoustical Society of Korea
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    • v.5 no.3
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    • pp.44-49
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    • 1986
  • 회로의 간편성에 최대 역점을 두어 PLL을 이용한 정현파 간섭음을 실시간으로 제거하는 방식을 제안하였다. SC 여파기를 이용한 적응 노치 여파기ㅘ 적응 대역 여파기를 자기 동조법으로 구동시킴으 로써 간섭음을 제거하였다. SC 여파기의 구동 스위칭 주파수는 제거하려는 신호 주파수으 L49배가 되 도록 하엿으며 소자의 동작 특성상 4KHz의 간섭음 제거 대역을 갖게 된다. 노치 여파기는 6차 여파기 이고 감쇄도는 중심 주파수에서 약 -56dB이다.

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