• 제목/요약/키워드: Distinguishability

검색결과 18건 처리시간 0.026초

X선 단순촬영에 있어서 신장결석의 출현에 관한 검토 (A Study on the Phenomena of Renal Stone in Simple Radiography)

  • 유장수;송재관;허준
    • 대한방사선기술학회지:방사선기술과학
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    • 제12권1호
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    • pp.25-29
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    • 1989
  • This paper investigated on influence on the distinguishability of renal stone in the accordance with thickness of object, x-ray tube voltage and base density. In the relationship between object and renal stone shadow, object and tube voltage, the obtained results can be summarized as the following. 1. When thickness of object was thin, the distinguishability increased in base density $2.0{\sim}2.5$, but for adults was best shown in base density 1.5. 2. In the relationship between object and tube voltage, the distinguishability increased at lower tube voltages ($50{\sim}60\;kVp$), using grid. As mentioned above, it was thought that this method was very effective in describing the phenomena of renal stone in film density 1.5, tube voltages 60 kVp.

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엔트로피와 분자 특성, 상 및 성분의 관계 (Entropy and its Relation with the Property of Molecule, Phase and Component)

  • 장재언
    • Korean Chemical Engineering Research
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    • 제61권1호
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    • pp.116-122
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    • 2023
  • 열역학 계를 구성하는 분자들의 특성, 거시적 규정의 성분, 상의 종류가 엔트로피에 미치는 관련성을 고찰하였다. 같은 성분에 속하는 분자들의 불구별성에 대하여 고전역학과 양자역학의 관점의 차이를 이해하고, 분자의 특성이 거시적 분류의 기준인 '성분'과 부합하는가를 검토하였다. 계의 열역학적 미시 상태에 관한 정의를 명확히 함으로써 분자의 구별성에 기인하는 볼츠만 통계학의 결함을 제거하고, 그 결과로 엔트로피에 대한 깁스 역설이 해소된다. 유체 및 고체의 상 변화에서 분자의 불구별성, 대칭수, 그리고 실현되는 미시 상태들의 수의 변화가 분배 함수와 엔트로피에 미치는 영향을 고찰하였다. 특히, 결정성 고체는 에르고딕 가설을 따르지 않는 열역학 계로 다룰 수 있음을 보인다.

Chemometric A spects of Sugar Profiles in Fruit Juices Using HPLC and GC

  • 윤정현;김건;이동선
    • Bulletin of the Korean Chemical Society
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    • 제18권7호
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    • pp.695-702
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    • 1997
  • The objective of this work is to determine the sugar profiles in commercial fruit juices, and to obtain chemometric characteristics. Sugar compositions of fruit juices were determined by HPLC-RID and GC-FID via methoxymation and trimethylsilylation with BSTFA. The appearance of multiple peaks in GC analysis for carbohydrates was disadvantageous as described in earlier literatures. Fructose, glucose, and sucrose were major carbohydrates in most fruit juices. Glucose/fructose ratios obtained by GC were lower than those by HPLC. Orange juices are similar to pineapple juices in the sugar profiles. However, grape juices are characterized by its lower or no detectable sucrose content. In addition, it was also found that unsweeten juices contained considerable level of sucrose. Chemometric technique such as principal components analysis was applied to provide an overview of the distinguishability of fruit juices based on HPLC or GC data. Principal components plot showed that different fruit juices grouped into distinct cluster. Principal components analysis was very useful in fruit juices industry for many aspects such as pattern recognition, detection of adulterants, and quality evaluation.

Mixing matrix estimation method for dual-channel time-frequency overlapped signals based on interval probability

  • Liu, Zhipeng;Li, Lichun;Zheng, Ziru
    • ETRI Journal
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    • 제41권5호
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    • pp.658-669
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    • 2019
  • For dual-channel time-frequency (TF) overlapped signals with low sparsity in underdetermined blind source separation (UBSS), this paper proposes an effective method based on interval probability to estimate and expand the types of mixing matrices. First, the detection of TF single-source points (TF-SSP) is used to improve the TF sparsity of each source. For more distinguishability, as the ratios of the coefficients from different columns of the mixing matrix are close, a local peak-detection mechanism based on interval probability (LPIP) is proposed. LPIP utilizes uniform subintervals to optimize and classify the TF coefficient ratios of the detected TF-SSP effectively in the case of a high level of TF overlap among sources and reduces the TF interference points and redundant signal features greatly to enhance the estimation accuracy. The simulation results show that under both noiseless and noisy cases, the proposed method performs better than the selected mainstream traditional methods, has good robustness, and has low algorithm complexity.

Improving Adversarial Domain Adaptation with Mixup Regularization

  • Bayarchimeg Kalina;Youngbok Cho
    • Journal of information and communication convergence engineering
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    • 제21권2호
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    • pp.139-144
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    • 2023
  • Engineers prefer deep neural networks (DNNs) for solving computer vision problems. However, DNNs pose two major problems. First, neural networks require large amounts of well-labeled data for training. Second, the covariate shift problem is common in computer vision problems. Domain adaptation has been proposed to mitigate this problem. Recent work on adversarial-learning-based unsupervised domain adaptation (UDA) has explained transferability and enabled the model to learn robust features. Despite this advantage, current methods do not guarantee the distinguishability of the latent space unless they consider class-aware information of the target domain. Furthermore, source and target examples alone cannot efficiently extract domain-invariant features from the encoded spaces. To alleviate the problems of existing UDA methods, we propose the mixup regularization in adversarial discriminative domain adaptation (ADDA) method. We validated the effectiveness and generality of the proposed method by performing experiments under three adaptation scenarios: MNIST to USPS, SVHN to MNIST, and MNIST to MNIST-M.

마이코박테리움을 신속하게 배양할 수 있는 성장 인자에 관한 연구 (Study on the Growth Factors for Rapidly Cultivating Mycobacterium spp.)

  • 하성일;박강균;석현수;신정섭;신동필;권민오;박연준
    • 대한임상검사과학회지
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    • 제51권2호
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    • pp.177-184
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    • 2019
  • Mycobacterium은 느리게 성장한다. 따라서 고체배지는 8주, 액체배지는 6주 동안 사용하여야 한다. 이 연구의 목적은 Mycobacterium을 빠르게 성장시킬 수 있는 성장 인자를 찾고, 신속한 동정을 위한 고체배지를 개발하는 데 도움을 주는 것이다. $Difco^{TM}$ Mycobacteria 7H11 agar (Becton, Dickinson and Company)에 activated charcoal, defibrinated sheep blood, L-ascorbic acid를 첨가하여 10종의 Mycobacteria 가지고 Mycobacterium 성장 인자 3가지를 평가하였다. 집락의 검출 시간 및 판독 용이성을 현재의 방법과 비교하였다. 빠르게 성장하는 Mycobacterium 있어 새로운 배지와 기존의 배지에서 검출 시간의 차이는 새로운 배지가 더 빠르다는 것을 확인시켜 주었다. M. kansasii와 M. intracelluare는 7H11 배지보다 7H11 C 배지에서 더 빠르게 자라는 것으로 확인되었다. MTB는 7H11 C 배지에서 다른 배지보다 빠르게 성장하였다. 이 연구는 2 두 가지 성장 인자가 빠르게 성장하는 Mycobacteria과 느리게 성장하는 Mycobacteria에 영향을 주는 것으로 확인되었다. 7H11 C 배지는 색상 대비로 인하여 10종의 모든 Mycobacterium에서 기존배지보다 더 뛰어난 판독 용이성을 보여 주었다. 특히, MTB가 성장했을 경우 집락의 크기가 다른 배지에서 보다 커서 시각화가 용이하였다.

Object Classification based on Weakly Supervised E2LSH and Saliency map Weighting

  • Zhao, Yongwei;Li, Bicheng;Liu, Xin;Ke, Shengcai
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권1호
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    • pp.364-380
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    • 2016
  • The most popular approach in object classification is based on the bag of visual-words model, which has several fundamental problems that restricting the performance of this method, such as low time efficiency, the synonym and polysemy of visual words, and the lack of spatial information between visual words. In view of this, an object classification based on weakly supervised E2LSH and saliency map weighting is proposed. Firstly, E2LSH (Exact Euclidean Locality Sensitive Hashing) is employed to generate a group of weakly randomized visual dictionary by clustering SIFT features of the training dataset, and the selecting process of hash functions is effectively supervised inspired by the random forest ideas to reduce the randomcity of E2LSH. Secondly, graph-based visual saliency (GBVS) algorithm is applied to detect the saliency map of different images and weight the visual words according to the saliency prior. Finally, saliency map weighted visual language model is carried out to accomplish object classification. Experimental results datasets of Pascal 2007 and Caltech-256 indicate that the distinguishability of objects is effectively improved and our method is superior to the state-of-the-art object classification methods.

A High Performance Permanent Magnet Synchronous Motor Servo System Using Predictive Functional Control and Kalman Filter

  • Wang, Shuang;Zhu, Wenju;Shi, Jian;Ji, Hua;Huang, Surong
    • Journal of Power Electronics
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    • 제15권6호
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    • pp.1547-1558
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    • 2015
  • A predictive functional control (PFC) scheme for permanent magnet synchronous motor (PMSM) servo systems is proposed in this paper. The PFC-based method is first introduced in the control design of speed loop. Since the accuracy of the PFC model is influenced by external disturbances and speed detection quantization errors of the low distinguishability optical encoder in servo systems, it is noted that the standard PFC method does not achieve satisfactory results in the presence of strong disturbances. This paper adopted the Kalman filter to observe the load torque, the rotor position and the rotor angular velocity under the condition of a limited precision encoder. The observations are then fed back into PFC model to rebuild it when considering the influence of perturbation. Therefore, an improved PFC method, called the PFC+Kalman filter method, is presented, and a high performance PMSM servo system was achieved. The validity of the proposed controller was tested via experiments. Excellent results were obtained with respect to the speed trajectory tracking, stability, and disturbance rejection.

미꾸리 Misgrunus anguillicaudatus (Cypriniformes: Cobitidae)의 난발생 및 자치어 형태발달 (Morphological Development of Eggs, Larvae and Juveniles of the Misgrunus anguillicaudatus (Cypriniformes: Cobitidae))

  • 박재민;유동재;손준혁;한경호
    • 한국수산과학회지
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    • 제55권1호
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    • pp.23-29
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    • 2022
  • This study was carried out to clarify the egg, larvae and juveniles development of Misgurnus anguillicaudatus, and relationships of M. anguillicaudatus and M. mizolepis, Cobitididae Fishes. The adult fishes were collected in Samsan-cheon, Haenam-gun, Jeollanam-do, Korea and their spawning inducement was carried by ovaprim injections. The egg shape was circular and the size was average 1.12 mm. The eggs were hatched at 61 to 72 h after fertilization. The newly hatched larvae had an average 3.23 mm in total length (TL). At 5 days after hatching, the larvae reached to post larval stage and they were 10.3 mm in TL. At 19 days after hatching, it reached to juvenile stage and was 25.3 mm in TL. The egg size of M. anguillicaudatus was almost same as M. mizolepis but the hatching period of M. anguillicaudatus has taken longer. It was possible for interspecific distinguishability of M. anguillicaudatus and M. mizolepis when their larvae reached to juvenile stage by the development of keel-like ridges.

Application of Wavelet-Based RF Fingerprinting to Enhance Wireless Network Security

  • Klein, Randall W.;Temple, Michael A.;Mendenhall, Michael J.
    • Journal of Communications and Networks
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    • 제11권6호
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    • pp.544-555
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    • 2009
  • This work continues a trend of developments aimed at exploiting the physical layer of the open systems interconnection (OSI) model to enhance wireless network security. The goal is to augment activity occurring across other OSI layers and provide improved safeguards against unauthorized access. Relative to intrusion detection and anti-spoofing, this paper provides details for a proof-of-concept investigation involving "air monitor" applications where physical equipment constraints are not overly restrictive. In this case, RF fingerprinting is emerging as a viable security measure for providing device-specific identification (manufacturer, model, and/or serial number). RF fingerprint features can be extracted from various regions of collected bursts, the detection of which has been extensively researched. Given reliable burst detection, the near-term challenge is to find robust fingerprint features to improve device distinguishability. This is addressed here using wavelet domain (WD) RF fingerprinting based on dual-tree complex wavelet transform (DT-$\mathbb{C}WT$) features extracted from the non-transient preamble response of OFDM-based 802.11a signals. Intra-manufacturer classification performance is evaluated using four like-model Cisco devices with dissimilar serial numbers. WD fingerprinting effectiveness is demonstrated using Fisher-based multiple discriminant analysis (MDA) with maximum likelihood (ML) classification. The effects of varying channel SNR, burst detection error and dissimilar SNRs for MDA/ML training and classification are considered. Relative to time domain (TD) RF fingerprinting, WD fingerprinting with DT-$\mathbb{C}WT$ features emerged as the superior alternative for all scenarios at SNRs below 20 dB while achieving performance gains of up to 8 dB at 80% classification accuracy.