• Title/Summary/Keyword: Threshold model

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External Validation of a Clinical Scoring System for Hematuria

  • Lee, Seung Bae;Kim, Hyung Suk;Kim, Myong;Ku, Ja Hyeon
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6819-6822
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    • 2014
  • Background: The aim of this study was to evaluate the accuracy of a new scoring system in Korean patients with hematuria at high risk of bladder cancer. Materials and Methods: A total of 319 consecutive patients presenting with painless hematuria without a history of bladder cancer were analyzed, from the period of August 2012 to February 2014. All patients underwent clinical examination, and 22 patients with incomplete data were excluded from the final validation data set. The scoring system included four clinical parameters: age (${\geq}50$ = 2 vs. <50 =1), gender (male = 2 vs. female = 1), history of smoking (smoker/ex-smoker = 4 vs. non-smoker = 2) and nature of the hematuria (gross = 6 vs. microscopic = 2). Results: The area under the receiver-operating characteristic curve (95% confidence interval) of the scoring system was 0.718 (0.655-0.777). The calibration plot demonstrated a slight underestimation of bladder cancer probability, but the model had reasonable calibration. Decision curve analysis revealed that the use of model was associated with net benefit gains over the treat-all strategy. The scoring system performed well across a wide range of threshold probabilities (15%-45%). Conclusions: The scoring system developed is a highly accurate predictive tool for patients with hematuria. Although further improvements are needed, utilization of this system may assist primary care physicians and other healthcare practitioners in determining a patient's risk of bladder cancer.

Markov CAC model in Wireless Mobile Networks Using AMC (AMC를 사용하는 무선 이동 네트워크에서 Markov CAC 모델)

  • Kwon Eun-Hyun;Park Hyo-Soon;Lee Jai-Yong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.4B
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    • pp.270-277
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    • 2006
  • In the wireless adaptive modulation and coding(AMC) systems, the modulation type of user's connection can be changed dynamically. and the ongoing connection might fail due to the change of modulation. In this paper, we approach the AMC-induced CAC problem by focusing on the guaranteed connection. Three kinds of calls, new, handoff, and modulation-changed calls, are considered. We propose a modified guard channel CAC scheme that allows the modulation-changed and handoff calls to use the guard channel. Then we analyze a Markov model for the CAC scheme with long-term AMC in mind. According to the simulation results, the proposed approach reduces the call dropping probability for modulation-changed calls, which suggests the threshold of guard channels can be determined based on the proposed approach.

Development and Evaluation of an Address Input System Employing Speech Recognition (음성인식 기능을 가진 주소입력 시스템의 개발과 평가)

  • 김득수;황철준;정현열
    • The Journal of the Acoustical Society of Korea
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    • v.18 no.2
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    • pp.3-10
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    • 1999
  • This paper describes the development and evaluation of a Korean address input system employing automatic speech recognition technique as user interface for input Korean address. Address consists of cities, provinces and counties. The system works on a window 95 environment of personal computer with built-in soundcard. In the speech recognition part, the Continuous density Hidden Markov Model(CHMM) for making phoneme like units(PLUs) and One Pass Dynamic Programming(OPDP) algorithm is used for recognition. For address recognition, Finite State Automata(FSA) suitable for Korean address structure is constructed. To achieve an acceptable performance against the variation of speakers, microphones, and environmental noises, Maximum a posteriori(MAP) estimation is implemented in adaptation. And to improve the recognition speed, fast search method using variable pruning threshold is newly proposed. In the evaluation tests conducted for the 100 connected words uttered by 3 males the system showed above average 96.0% of recognition accuracy for connected words after adaption and recognition speed within 2 seconds, showing the effectiveness of the system.

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Non-linear regression model considering all association thresholds for decision of association rule numbers (기본적인 연관평가기준 전부를 고려한 비선형 회귀모형에 의한 연관성 규칙 수의 결정)

  • Park, Hee Chang
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.2
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    • pp.267-275
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    • 2013
  • Among data mining techniques, the association rule is the most recently developed technique, and it finds the relevance between two items in a large database. And it is directly applied in the field because it clearly quantifies the relationship between two or more items. When we determine whether an association rule is meaningful, we utilize interestingness measures such as support, confidence, and lift. Interestingness measures are meaningful in that it shows the causes for pruning uninteresting rules statistically or logically. But the criteria of these measures are chosen by experiences, and the number of useful rules is hard to estimate. If too many rules are generated, we cannot effectively extract the useful rules.In this paper, we designed a variety of non-linear regression equations considering all association thresholds between the number of rules and three interestingness measures. And then we diagnosed multi-collinearity and autocorrelation problems, and used analysis of variance results and adjusted coefficients of determination for the best model through numerical experiments.

Prediction of Pain Expression Using the Extended Gate Control Theory of Pain and Fishbein′s Model (관문통제동통이론과 FISHBEIN의 모델을 이용한 동통표현 예견에 대한 연구)

  • 이은옥
    • Journal of Korean Academy of Nursing
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    • v.13 no.2
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    • pp.1-21
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    • 1983
  • The purposes of this study were to(a) develop theoretical modifications of the extended gate control theory of pain using Fishbein's model and(b) test the efficacy of these modifications. Attitude, social subjective norm, personal subjective norm, habit and state anxiety were operationalized to represent internal stimuli for the cognitive-evaluative and motivational-affective dimensions of the theory. Pain expression was operationalized as sensory and affective responses to pain, and pain endurance. Sixty-two female nurses from 20 to 50 years of age participated. A semantic differential scale measured attitude and motivations to comply; a Likerty-type scale measured personal and social norms and habit. Spielberger's STAI measured state anxiety, Pain was produced using a modified submaximum effort tourniquet technique. Pair expression was measured using ratio scales of sensory intensity and unpleasantness developed by Gracely and his associates. Pain endurance was measured by subtracting time of pain threshold from pain tolerance. The first hypothesis examining whether pain endurance would be more significantly related to the affective response than to the sensory response was net rejected. Four remaining hypotheses, testing the ability of the five variables to predict the sensory and affective responses were not rejected. However, the habit of pain expression and the attitude toward pain expression contributed to the prediction of both sensory and affective responses to pain. The interaction between the cognitive-evaluative and the sensory-discriminative dimensions and the interaction between the cognitive-evaluative and motivational-affective dimensions were partially supported by the data from these two variables. The interaction between the motivational-affective and the sensory-discriminative dimensions was also supported by the relationship of sensory to affective responses. The variables which did not significantly predict pain expression appeared to have potential for prediction. Revision and testing of the tools for better reliability, validity, and clinical usuability are needed. The study contributed to theory building. The identification of variables which pre-dict pain behavior must occur before effective nursing interventions can be developed.

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Group Key Management with Low Cost Rekey (저비용 rekey를 갖는 그룹키 관리)

  • Chung, Jong-In
    • The Journal of Korean Association of Computer Education
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    • v.7 no.1
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    • pp.55-66
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    • 2004
  • The Internet today provides group communication model, multicast service. It is important to keep security for multicast communication. Member leaving is associated with scalability problem for group key management. If one member of the group is removed, new group key has to be changed and communicated to all remaining members of group. Modification and distribution of new group keys for rekeying is an expensive operation. Minimizing the number of messages and operation cost for generation of the composite keys are important evaluating criteria of multicast key management scheme. Periodic rekey helps reducing these important parameters rather than removing members sequentially in fashion one after another. In this paper, Hamming distance is calculated between every members to be removed. The members with Hamming distance less than threshold are selected for rekeying procedure. With running the round assignment algorithm, our model has advantages of reducing the number of message and operation cost for generation of the composite keys for rekeying.

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Bit Operation Optimization and DNN Application using GPU Acceleration (GPU 가속기를 통한 비트 연산 최적화 및 DNN 응용)

  • Kim, Sang Hyeok;Lee, Jae Heung
    • Journal of IKEEE
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    • v.23 no.4
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    • pp.1314-1320
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    • 2019
  • In this paper, we propose a new method for optimizing bit operations and applying them to DNN(Deep Neural Network) in software environment. As a method for this, we propose a packing function for bitwise optimization and a masking matrix multiplication operation for application to DNN. The packing function converts 32-bit real value to 2-bit quantization value through threshold comparison operation. When this sequence is over, four 32-bit real values are changed to one 8-bit value. The masking matrix multiplication operation consists of a special operation for multiplying the packed weight value with the normal input value. And each operation was then processed in parallel using a GPU accelerator. As a result of this experiment, memory saved about 16 times than 32-bit DNN Model. Nevertheless, the accuracy was within 1%, similar to the 32-bit model.

Robust Speech Recognition Using Missing Data Theory (손실 데이터 이론을 이용한 강인한 음성 인식)

  • 김락용;조훈영;오영환
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.3
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    • pp.56-62
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    • 2001
  • In this paper, we adopt a missing data theory to speech recognition. It can be used in order to maintain high performance of speech recognizer when the missing data occurs. In general, hidden Markov model (HMM) is used as a stochastic classifier for speech recognition task. Acoustic events are represented by continuous probability density function in continuous density HMM(CDHMM). The missing data theory has an advantage that can be easily applicable to this CDHMM. A marginalization method is used for processing missing data because it has small complexity and is easy to apply to automatic speech recognition (ASR). Also, a spectral subtraction is used for detecting missing data. If the difference between the energy of speech and that of background noise is below given threshold value, we determine that missing has occurred. We propose a new method that examines the reliability of detected missing data using voicing probability. The voicing probability is used to find voiced frames. It is used to process the missing data in voiced region that has more redundant information than consonants. The experimental results showed that our method improves performance than baseline system that uses spectral subtraction method only. In 452 words isolated word recognition experiment, the proposed method using the voicing probability reduced the average word error rate by 12% in a typical noise situation.

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Effect of Temperature on Development of Oriental Tobacco Budworm, Helicoverpa assuta Guenee (담배나방 발육에 미치는 온도의 영향)

  • 한만위;이준호;이문홍
    • Korean journal of applied entomology
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    • v.32 no.2
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    • pp.236-244
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    • 1993
  • The development of OrientaL tobacco budworm (OTE), Heticoverpa assulta, was studied at seven constant temperatures from 18 to $33^{\circ}C$ with a 14L : 10D photoperiod on the artificial diet. The egg, larval, and pupal duration comprised ca. 10, 48, and 42% of the total developmental time (from egg to adult emergence). The lower developmental threshold temperatures for egg, larval, pupal, and overall development were 8.62, 12.65, 11.64, and $11.89^{\circ}C$, respectively. The biophysical model of Sharpe & DeMichele (1977) provided a good description of OTB's development as a function of temperature ($r^2$=0.993~O.996). The Wmbull distribution was fitted to cumulative frequency distributions of normalized developmental times for each developmental stage of OTE ($r^2$== 0.987 ~0.999).

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FINITE TEMPERATURE EFFECTS ON SPIN POLARIZATION OF NEUTRON MATTER IN A STRONG MAGNETIC FIELD

  • Isayev, Alexander A.;Yang, Jong-Mann
    • Journal of The Korean Astronomical Society
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    • v.43 no.5
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    • pp.161-168
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    • 2010
  • Magnetars are neutron stars possessing a magnetic field of about $10^{14}-10^{15}$ G at the surface. Thermodynamic properties of neutron star matter, approximated by pure neutron matter, are considered at finite temperature in strong magnetic fields up to $10^{18}$ G which could be relevant for the inner regions of magnetars. In the model with the Skyrme effective interaction, it is shown that a thermodynamically stable branch of solutions for the spin polarization parameter corresponds to the case when the majority of neutron spins are oriented opposite to the direction of the magnetic field (i.e. negative spin polarization). Moreover, starting from some threshold density, the self-consistent equations have also two other branches of solutions, corresponding to positive spin polarization. The influence of finite temperatures on spin polarization remains moderate in the Skyrme model up to temperatures relevant for protoneutron stars. In particular, the scenario with the metastable state characterized by positive spin polarization, considered at zero temperature in Phys. Rev. C 80, 065801 (2009), is preserved at finite temperatures as well. It is shown that, above certain density, the entropy for various branches of spin polarization in neutron matter with the Skyrme interaction in a strong magnetic field shows the unusual behavior, being larger than that of the nonpolarized state. By providing the corresponding low-temperature analysis, we prove that this unexpected behavior should be related to the dependence of the entropy of a spin polarized state on the effective masses of neutrons with spin up and spin down, and to a certain constraint on them which is violated in the respective density range.