• Title/Summary/Keyword: Action time

Search Result 2,482, Processing Time 0.033 seconds

Review on controllers with a time delay estimation (시간지연추정제어기에 관한 리뷰)

  • Lee H.J.;Yoon J.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2005.06a
    • /
    • pp.1120-1124
    • /
    • 2005
  • We reviewed controllers with a time delay estimation in this paper. Time delay control (TDC) and sliding mode control (SMC) are well known robust control schemes. Basically, the TDC has a main characteristic called a time delay estimation from which we can estimate the total uncertainty of a system. . The TDC causes the stick-slip in the case of systems with a friction. The so-called TDCSA which are short for TDC with switching action was developed to reduce the stick-slip. The TDC has the additional switching action term in the TDC structure. In the other hand, the SMC dose not have a time delay estimation but instead it can estimate the system uncertainty through the switching action. The SMC has a difficulty to estimate the total uncertainty of a system because it does not have a time delay estimation. In order to solve the difficulty, some control schemes were developed. Among them, we need to focus our attention on two control schemes: SMCPE and SMCTE, which are short for sliding mode control with a perturbation estimation and sliding mode control with a time delay estimation, respectively. In this paper, we analyzed and compared the characteristic of above three controllers. Even though the motives for the development of three control schemes are different, three control schemes have much in common in terms of their controller structures.

  • PDF

The Balancing Act of Action and Learning: A Systematic Review of the Action Learning Literature

  • CHO, Yonjoo
    • Educational Technology International
    • /
    • v.9 no.1
    • /
    • pp.1-23
    • /
    • 2008
  • Despite considerable commitment to the application of action learning as an organization development intervention, no identified systematic investigation of action learning practices has been reported. Based on a systematic literature review, the purpose of this paper is to identify whether researchers strike a balance between action and learning in their studies of action learning. Research findings in this study included: (1) only 32 empirical studies were found from the electronic database search; (2) based on the hypothesized continuum of Revans' original proposition of balancing action and learning, the author categorized 32 studies into three groups: action-oriented, learning-oriented, and balanced action learning; (3) there were only nine studies on balanced action learning among 32 empirical studies, whose insights included an effective use of project teams, applications of action learning for organization development, and key success factors such as time, reflection, and management support; (4) case study was among the most frequently used research method and only six quality studies met key methodological traits; and (5) therefore, more rigorous empirical research employing quantitative methods as well as case studies is needed to determine whether researchers strike a balance between action and learning in studies on action learning.

Real-Time Cattle Action Recognition for Estrus Detection

  • Heo, Eui-Ju;Ahn, Sung-Jin;Choi, Kang-Sun
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.13 no.4
    • /
    • pp.2148-2161
    • /
    • 2019
  • In this paper, we present a real-time cattle action recognition algorithm to detect the estrus phase of cattle from a live video stream. In order to classify cattle movement, specifically, to detect the mounting action, the most observable sign of the estrus phase, a simple yet effective feature description exploiting motion history images (MHI) is designed. By learning the proposed features using the support vector machine framework, various representative cattle actions, such as mounting, walking, tail wagging, and foot stamping, can be recognized robustly in complex scenes. Thanks to low complexity of the proposed action recognition algorithm, multiple cattle in three enclosures can be monitored simultaneously using a single fisheye camera. Through extensive experiments with real video streams, we confirmed that the proposed algorithm outperforms a conventional human action recognition algorithm by 18% in terms of recognition accuracy even with much smaller dimensional feature description.

English Teachers' Responses to Doing Action Research

  • Yang, Tae-Sun
    • English Language & Literature Teaching
    • /
    • v.15 no.2
    • /
    • pp.245-259
    • /
    • 2009
  • The purpose of this study was to investigate English teachers' perceptions about doing their own action research to find out the benefits of involvement in action research. I believe that teachers should engage in curriculum research and development because it relates to their own classrooms and because a primary aim for teacher education program is to give teachers ways of exploring their own classrooms. I focused on 17 graduate students who had undertaken action research during the fall semester of 2007 and administered a questionnaire about their perceptions of doing action research. The results revealed that their perceptions of doing action research fell into the following two categories, positive and negative aspects. For positive aspects, they experienced a sense of personal and professional growth and they underwent identity transformation from passive, etic-oriented, and uncritical to active, emic-oriented, and critical teachers. However, many of them expressed that major obstacles to doing action research were time constraints and lack of skills or training in conducting action research. Thus, it is suggested that both pre- and in-service teachers should consider conducting a language teaching diary study, doing collaborative action research, and acquiring all the necessary skills for conducting action research.

  • PDF

Analysis for the causes of sea collisions, with particular emphasis on the lookout (선박충돌사고의 원인분석(경계를 중심으로))

  • Hugh, I.;Joo, J.H.
    • Journal of the Korean Institute of Navigation
    • /
    • v.12 no.1
    • /
    • pp.71-84
    • /
    • 1988
  • For traffic proceeding in random directions on a plane surface the frequency of collision, if no avoiding action in taken ,is approximately proportional to the square of the traffic density and directly proportional to the size and speed of the ship, Avoiding is normally taken and the rte of collisions is therefore also governed by additional factors such as the visibility, the effectiveness of the collisionavoidance rules, the competence of personnel or watchkeeping attitude, the maneuverability of the ship and the efficiency of radar and other equipments. From the viewpoint of watchkeeper who is responsible for maneuvering, watchkeeping attitude such as lookout and action to avoid collision is the most controllable factor among those mentioned above. In practice, according to the investigation of the institution of marine courts, about 50% co collisions occurred is caused by disorbedience to steering and sailing rules of international regulations for preventing collision at sea including lookout. So we classify the process of collisions with first sight of another ship , assessment of risk of collisions and action to avoid collisions and make a factural survey about lookout and action to avoid collisions from the point on "time" and " distance", namely relationship among ship's size, speed, first sight time of another ship, action to avoid collisions ,and distance from sight of another ship to collision occurred. According to the results of the actual survey , we come to conclude that most of collisions occurred are due to improper lookout and ineffective action to avoid collision which means time lag from first sight of another ship to time of action taken to avoid collision is relatively long. is relatively long.

  • PDF

Studies on the Hemostatic Action and the Effects on the Isolated Uterus Muscle of Combined Preparation of Crude Drugs ( I ) -On Kwibitang- (복합생약제제(複合生藥製劑)의 지혈작용(止血作用) 및 적출자궁근(摘出子宮筋)에 미치는 영향(影響)(제1보)(第1報) -귀비탕(歸脾湯)에 대(對)하여-)

  • Yoo, Dong-Youl;Park, Byeong-Ryeol;Eun, Jae-Soon
    • Korean Journal of Pharmacognosy
    • /
    • v.19 no.1
    • /
    • pp.39-46
    • /
    • 1988
  • Experimental studies were conducted to investigate the hemostatic effect of the water extracts of Kwibitang. For this purpose, the effects of the extracts on the bleeding time in mouse tail and prothrombin time in vitro were estimated. Furthermore, its activity on the isolated uterine muscle in rats were investigated. The results obtained were as following; The bleeding time was not shortened, but the plasma prothrombin time in vitro test was significantly shortened. The uterotonic action produced by the extract was not inhibited by pretreatment of diltiazem at the doses of $10^{-5}g/ml$.

  • PDF

Effect of Action Observational Training on Gait in People with Stroke

  • Lee, JongSu;Kim, YoungMi;Lee, DongKyu
    • The Journal of Korean Physical Therapy
    • /
    • v.32 no.1
    • /
    • pp.1-6
    • /
    • 2020
  • Purpose: This study examined the effects of action observational training to improve the gait function for patients with stroke. Methods: The participants were divided into two groups: right hemiplegia group (n=12) and left hemiplegia group (n=12). All groups received conventional therapy for five sessions for 30 minutes, each for three weeks. Left and right hemiplegia group practiced additional action observational training for five sessions for 20 minutes each for three weeks. They participated in three weeks of action observational training coupled with immediate physical practice (intervention), followed by a final assessment. The duration of each action observation video sequence was 10 minutes, followed immediately by practice of the observed motor skill (10 minutes). The gait velocity, cadence, swing time, step length, and BOS (base of support) were examined using the GAITRite system. Results: The results of this study showed significant improvement in the gait function. The outcomes of the gait abilities from gait velocity, cadence, swing time, step length of the affected side, and BOS (base of support) were improved significantly in the right hemiplegia group (p<0.05). In the left hemiplegia group, there was no significant improvement in the gait velocity, cadence, and BOS except for the swing time and step length of the affected side. The left and right group comparisons between the groups were not significant (p<0.05). Conclusion: Action observation training improves the gait function. These results suggest that action observational training is feasible and suitable for stroke patients.

Update Thresholds of More Accurate Time Stamp for Event Reconstruction (이벤트 재구성을 위한 타임스탬프 갱신 임계치)

  • James, Joshua I.;Jang, Yunsik
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.17 no.2
    • /
    • pp.7-13
    • /
    • 2017
  • Many systems rely on reliable timestamps to determine the time of a particular action or event. This is especially true in digital investigations where investigators are attempting to determine when a suspect actually committed an action. The challenge, however, is that objects are not updated at the exact moment that an event occurs, but within some time-span after the actual event. In this work we define a simple model of digital systems with objects that have associated timestamps. The model is used to predict object update patterns for objects with associated timestamps, and make predictions about these update time-spans. Through empirical studies of digital systems, we show that timestamp update patterns are not instantaneous. We then provide a method for calculating the distribution of timestamp updates on a particular system to determine more accurate action instance times.

Comparison of EEG Changes Induced by Action Execution and Action Observation

  • Kim, Ji Young;Ko, Yu-Min;Park, Ji Won
    • The Journal of Korean Physical Therapy
    • /
    • v.29 no.1
    • /
    • pp.27-32
    • /
    • 2017
  • Purpose: Recent electrophysiological studies have shown that the sensorymotor cortex is activated during both actual action excuted by themselves and observation of action performed by other persons. Observation of action based on mirror neuron system can be used as a cognitive intervention to promote motor learning. The purpose of this study was to investigate the brain activity changes during action observation and action execution using EEG. Methods: Thirty healthy volunteers participated and were requested to perform hand action and to observe the video of hand action performed by another person. The EEG activity was evaluated by a method which segregated the time-locked for each condition. To compare the differences between action observation and execution, the Mu suppression and the relative band power were analysed. Results: The results showed significant mu suppression during the action observation and execution, but the differences between the two conditions were not observed. The relative band power showed a significant difference during the action observation and execution, but there were no differences between the two conditions. Conclusion: These results indicate that action execution and observation involve overlapping neural networks in the sensorymotor cortical areas, proposing positive changes on neurophysiology. We are expected to provide information related to the intervention of cognitive rehabilitation.

Action Spectra of Apoptosis Induction and Reproductive Cell Death in L5178Y cells in UV-B Region

  • Mizuho Aoki;Yoshiya Furusawa;Higashi, Sho-ichi;Masakatsu Watanabe
    • Journal of Photoscience
    • /
    • v.9 no.2
    • /
    • pp.454-456
    • /
    • 2002
  • It is important to determine the action spectrum of UV-B radiation contained in the sunlight to estimate the risk of skin cancer. We have investigated action spectra for induction of apoptosis and reproductive cell death in L5178Y cells using the Okazaki Large Spectrograph at NIBB. L5178Y cells were exposed to light at different wavelengths in UV-B or UV-A region. Frequencies of apoptosis induction and reproductive cell death were determined by counting cells with chromatin condensation, and by the colony formation assay, respectively. The measured sensitivity spectra for the two end-points were in very good agreement. Sensitivity decreased steeply with increase of wavelength in UV-B region and remains nearly constant in UV-A region. The action spectra were also slightly steeper than that for the minimum erythematic dose (MED), but very similar to the light absorption spectrum of DNA in UV-B region. On the other hand, the spectra for both endpoints were similar to MED spectrum but not DNA spectrum in the UV-A region. Also different time-course and morphological difference of apoptosis were found between UV-B (long time, fragmentation) and UV-A (short time, shrinkage) region. These results suggest that DNA damage induced by UV-B light triggers apoptosis and reproductive cell death, but other damaged targets (membrane, protein and so on) trigger these effects in UV-A region.

  • PDF