• 제목/요약/키워드: randomization

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Real-time Acquisition of Three Dimensional NMR Spectra by Non-uniform Sampling and Maximum Entropy Processing

  • Jee, Jun-Goo
    • Bulletin of the Korean Chemical Society
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    • 제29권10호
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    • pp.2017-2022
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    • 2008
  • Of the experiments to shorten NMR measuring time by sparse sampling, non-uniform sampling (NUS) is advantageous. NUS miminizes systematic errors which arise due to the lack of samplings by randomization. In this study, I report the real-time acquisition of 3D NMR data using NUS and maximum-entropy (MaxEnt) data processing. The real-time acquisition combined with NUS can reduce NMR measuring time much more. Compared with multidimensional decomposition (MDD) method, which was originally suggested by Jaravine and Orekhov (JACS 2006, 13421-13426), MaxEnt is faster at least several times and more suitable for the realtime acquisition. The designed sampling schedule of current study makes all the spectra during acquisition have the comparable resulting resolutions by MaxEnt. Therefore, one can judge the quality of spectra easily by examining the intensities of peaks. I report two cases of 3D experiments as examples with the simulated subdataset from experimental data. In both cases, the spectra having good qualitie for data analysis could be obtained only with 3% of original data. Its corresponding NMR measuring time was 8 minutes for 3D HNCO of ubiquitin.

직무스트레스관리중재에 대한 논문 분석(1991-2004) (A Review of Studies the Job Stress Management Interventions(SMIs) conducted from 1991 to 2004)

  • 김정희
    • 한국직업건강간호학회지
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    • 제16권1호
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    • pp.15-27
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    • 2007
  • Purpose: This study was conducted to identify patterns and trends of studies of SMIs from 1999 to 2004, and to suggest the directions of future research activities. Method: 38 research studies of SMIs were selected and classified according to the sample characteristics, and the types of SMIs and outcome variables. Results: The number of SMIs studies has been increased since 1991, but it was more smaller than descriptive studies. They tended to be conducted more without the conceptual framework or randomization. Nurses were the most popular subjects and GHQ was more prevalent than other instruments. SMIs studies used confusedly in "job stress" terms. The outcome variables, most frequently measured were "anxiety and depression". 46 interventions were conducted in 38 studies. Most of them were individual worker-focused intervention and CBT was most frequently conducted. There were wide variations in duration, and intervals of SMIs. Conclusions: These results of this study will be used to guide the development of SMIs. And it was needed to identify and debate on 'stress' terms among the authors and to develop the SMIs. Also, it will be needed research that evaluate the effect of Job SMIs and experimental studies must be conducted rather than descriptive studies.

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기능적 발목 불안정성 축구 선수에 대한 움직임을 동반한 가동술과 테이핑 적용이 균형과 점프 수행력에 미치는 영향 (Effect of MWM and Taping on Balance and Jump Performance in Soccer Player with Functional Ankle Instability)

  • 정용식;정연우;정영준
    • 대한정형도수물리치료학회지
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    • 제22권1호
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    • pp.43-49
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    • 2016
  • Background: The purpose of this study was to investigate the effects on balance and Jump performance in soccer player with functional ankle instability of Movement with mobilization (MWM) and taping. Methods: In 30 male college soccer player with functional ankle instability subjects of this study randomization, fibular reposition taping (FRT) group (n=10), kinesio taping (KT) group (n=10), control group (n=10) that included in the MWM and taping was classified group.Before and after intervention, measured in surface area ellipse and countermovement jump with arm swing. Results: Showed a significant balance and jump performance from the FRT group and KT group compared to the control group. Showed a significant improvement in balance from the FRT group compared to the KT group. Conclusions: MMW and taping showed the increased balance and Jump performance in soccer player with functional ankle instability.

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Development of kNN QSAR Models for 3-Arylisoquinoline Antitumor Agents

  • Tropsha, Alexander;Golbraikh, Alexander;Cho, Won-Jea
    • Bulletin of the Korean Chemical Society
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    • 제32권7호
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    • pp.2397-2404
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    • 2011
  • Variable selection k nearest neighbor QSAR modeling approach was applied to a data set of 80 3-arylisoquinolines exhibiting cytotoxicity against human lung tumor cell line (A-549). All compounds were characterized with molecular topology descriptors calculated with the MolconnZ program. Seven compounds were randomly selected from the original dataset and used as an external validation set. The remaining subset of 73 compounds was divided into multiple training (56 to 61 compounds) and test (17 to 12 compounds) sets using a chemical diversity sampling method developed in this group. Highly predictive models characterized by the leave-one out cross-validated $R^2$ ($q^2$) values greater than 0.8 for the training sets and $R^2$ values greater than 0.7 for the test sets have been obtained. The robustness of models was confirmed by the Y-randomization test: all models built using training sets with randomly shuffled activities were characterized by low $q^2{\leq}0.26$ and $R^2{\leq}0.22$ for training and test sets, respectively. Twelve best models (with the highest values of both $q^2$ and $R^2$) predicted the activities of the external validation set of seven compounds with $R^2$ ranging from 0.71 to 0.93.

A Combined Pharmacophore-Based Virtual Screening, Docking Study and Molecular Dynamics (MD) Simulation Approach to Identify Inhibitors with Novel Scaffolds for Myeloid cell leukemia (Mcl-1)

  • Bao, Guang-Kai;Zhou, Lu;Wang, Tai-Jin;He, Lu-Fen;Liu, Tao
    • Bulletin of the Korean Chemical Society
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    • 제35권7호
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    • pp.2097-2108
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    • 2014
  • Chemical feature based quantitative pharmacophore models were generated using the HypoGen module implemented in DS2.5. The best hypothesis, Hypo1, which was characterized by the highest correlation coefficient (0.96), the highest cost difference (61.60) and the lowest RMSD (0.74), consisted of one hydrogen bond acceptor, one hydrogen bond donor, one hydrophobic and one ring aromatic. The reliability of Hypo1 was validated on the basis of cost analysis, test set, Fischer's randomization method and GH test method. The validated Hypo1 was used as a 3D search query to identify novel inhibitors. The screened molecules were further refined by employing ADMET, docking studies and visual inspection. Three compounds with novel scaffolds were selected as the most promising candidates for the designing of Mcl-1 antagonists. Finally, a 10 ns molecular dynamics simulation was carried out on the complex of receptor and the retrieved ligand to demonstrate that the binding mode was stable during the MD simulation.

A Query Randomizing Technique for breaking 'Filter Bubble'

  • Joo, Sangdon;Seo, Sukyung;Yoon, Youngmi
    • 한국컴퓨터정보학회논문지
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    • 제22권12호
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    • pp.117-123
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    • 2017
  • The personalized search algorithm is a search system that analyzes the user's IP, cookies, log data, and search history to recommend the desired information. As a result, users are isolated in the information frame recommended by the algorithm. This is called 'Filter bubble' phenomenon. Most of the personalized data can be deleted or changed by the user, but data stored in the service provider's server is difficult to access. This study suggests a way to neutralize personalization by keeping on sending random query words. This is to confuse the data accumulated in the server while performing search activities with words that are not related to the user. We have analyzed the rank change of the URL while conducting the search activity with 500 random query words once using the personalized account as the experimental group. To prove the effect, we set up a new account and set it as a control. We then searched the same set of queries with these two accounts, stored the URL data, and scored the rank variation. The URLs ranked on the upper page are weighted more than the lower-ranked URLs. At the beginning of the experiment, the difference between the scores of the two accounts was insignificant. As experiments continue, the number of random query words accumulated in the server increases and results show meaningful difference.

고혈압 침 임상연구에서 환자의 기대치와 치료효과 간의 상관관계 (The Relationship between Patients' Expectations of Treatment Effect and Clinical Outcome in a Trial of Acupuncture for Hypertension)

  • 김준범;류연;김정은;박지은
    • Journal of Acupuncture Research
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    • 제33권4호
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    • pp.33-38
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    • 2016
  • Objectives : To identify potential correlation between patients' expectations and clinical outcome in a randomized control study of acupuncture. Methods : In a clinical trial of acupuncture for hypertension, 60 participants with pre and mild hypertension were randomized into an acupuncture group and a control group. After randomization, all participants were asked to rate their expectation for the intervention on a scale of 0 to 10. To analyze the effect of expectation on clinical outcome, change of blood pressure was compared between high and low expectation groups. Results : There was no significant difference of baseline blood pressure between low expectation group and high expectation group. Proportion of acupuncture group and control group was also not different between low and high expectation groups (p = 0.638). The change of systolic blood pressure was -1.55 mmHg in low expectation group and -3.07 mmHg in high expectation group, and it was not significantly different (p = 0.54). There was no significant difference in the change of diastolic blood pressure between two groups (p = 0.58), with -3.24 mmHg in low expectation group and -2.34 mmHg in high expectation group. Conclusion : In this study, the expectation of intervention (including acupuncture treatment) was not associated with the effect of intervention.

실험설계법 기반 풍동시험 시스템 오차 검출 실험연구 (Experimental Investigations of Systematic Errors in Wind Tunnel Testing Using Design of Experiments)

  • 오세윤;박승오;안승기
    • 한국항공우주학회지
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    • 제41권5호
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    • pp.335-341
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    • 2013
  • 풍동시험 중에 발생하는 시스템오차의 변동에 관한 연구를 수행하였다. 회전익 항공기의 기체 공력특성 측정실험에 실험설계 방법론이 적용되었다. 풍동시험 중에 발생하는 시스템오차의 변동에 관한 연구를 수행하였다. 허용 실험오차 내에서 항상 동일한 결과를 얻어야 하는 전제조건에도 불구하고 한 개의 실험시간 블록에서 측정된 힘과 모멘트가 다른 시간블록에서 측정된 것과 상당량 다르게 측정되었다. 실험관련 시스템오차는 존재하지 않는다고 임의로 간주해서는 안되며 이러한 오차의 감소는 랜덤화, 블록화 및 반복화 등의 실험설계원리의 적용을 통해 가능하다.

새로운 3상 랜덤 펄스 위치 PWM기법에 의한 EPLD기반의 모터 속도제어 시스템 (EPLD based Induction Motor Drives with a New Three-Phase Randomized Pulse Position PWM Scheme)

  • 김회근;위석오;임영철;정영국;나석환
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2002년도 전력전자학술대회 논문집
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    • pp.308-312
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    • 2002
  • In this paper, EPLD(Erasable Programmable Logic Device) based induction motor drives with a SRP-PWM(Separatley Randomized Pulse Position PWM) is proposed. In the proposed RPWM (Random PWM), each of three phase pulses is located randomly in each switching interval. Based on the space vector modulation technique, the duty ratio of the pulses is calculated. To verify the validity of the proposed RPWM, the experimental study was tried. Along with the randomization of PWM pulses, the space vector modulation is also executed in the TMS320C31 DSP(Digital Signal Processor). The experimental results show that the voltage and switching noise harmonics are spread to a wide band area. Also, the performance of the proposed SRP-PWM and the conventional SVM-PWM are nearly the same from the viewpoing of the v/f constant control.

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한약을 이용한 chemotherapy-induced peripheral neuropathy (CIPN) 치료 관련 무작위 배정 임상 시험에 대한 고찰 (A review of herbal medicines for chemotherapy induced peripheral neuropathy)

  • 박봉기
    • 대한암한의학회지
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    • 제21권2호
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    • pp.51-61
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    • 2016
  • Background : Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse effect in cancer patients who were exposed to chemotherapy. CIPN impacts on the quality of life and could delay chemotherapy. The aim of this review was to assess the therapeutic effectiveness of herbal medicine in CIPN patients. Methods : Randomized controlled trials (RCTs) were included in this review. We searched MEDLINE, Cochrane database, EMBASE, CNKI, Wanfang and four Korean databases without restrictions on time or language. The risk of bias was assessed using the Cochrane risk of bias tool. Results : Eleven RCTs involving 706 patients met the inclusion criteria. Eleven different herbal medicines were examined in the included trials. Almost RCTs showed insufficiency in the reporting randomization method and allocation concealment. One trial used allocation concealment and a double-blinding method. Five studies reported that participants dropped out of RCTs and conducted an 'as-treated analysis'. One trials reported adverse effects of herbal medicine. In ten of the eleven trials, the use of herbal medicine had shown significant differences in clinical symptoms or nerve conduction velocity. Conclusions : The use of herbal medicines for CIPN showed significant improvements in the management of CIPN. However, conclusions cannot be drawn because of the generally low quality of methodology and low quantity of data for each single herbal medicine. Further rigorous trials are needed.