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Neuropsychology of Memory (기억의 신경심리학)

  • Rhee, Min-Kyu
    • Sleep Medicine and Psychophysiology
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    • v.4 no.1
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    • pp.1-14
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    • 1997
  • This paper reviewed models to explain memory and neuropsychological tests to assess memory. Memory was explained in cognitive and neuroanatomical perspectives, Cognitive model describes memory as structure and process. In structure model, memory is divided into three systems: sensory memory, short-term memory(working memory), and long-term memory. In process model, there are broadly three categories of memory process: encoding, storage, and retrieval. Memory process work in memory structure. There are two prominent models of the neuroanatomy of memory, derived from the work of Mishkin and Appenzeller and that of Squire and Zola-Morgan. These two models are the most useful for the clinician in part because they take into account the connections between the limbic and frontal cortical regions. The major difference between the two models concerns the role of the amygdala in memory processess. Mishkin and his colleagues believe that the amygdala plays a significant role while Squire and his colleagues do not. The most popular and widely used tests of memory ability such as WMS-R, AVLT, CVLT, HVLT. RBMT, CFT, and BVRT-R, were reviewed.

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Estimating pile setup parameter using XGBoost-based optimized models

  • Xigang Du;Ximeng Ma;Chenxi Dong;Mehrdad Sattari Nikkhoo
    • Geomechanics and Engineering
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    • v.36 no.3
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    • pp.259-276
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    • 2024
  • The undrained shear strength is widely acknowledged as a fundamental mechanical property of soil and is considered a critical engineering parameter. In recent years, researchers have employed various methodologies to evaluate the shear strength of soil under undrained conditions. These methods encompass both numerical analyses and empirical techniques, such as the cone penetration test (CPT), to gain insights into the properties and behavior of soil. However, several of these methods rely on correlation assumptions, which can lead to inconsistent accuracy and precision. The study involved the development of innovative methods using extreme gradient boosting (XGB) to predict the pile set-up component "A" based on two distinct data sets. The first data set includes average modified cone point bearing capacity (qt), average wall friction (fs), and effective vertical stress (σvo), while the second data set comprises plasticity index (PI), soil undrained shear cohesion (Su), and the over consolidation ratio (OCR). These data sets were utilized to develop XGBoost-based methods for predicting the pile set-up component "A". To optimize the internal hyperparameters of the XGBoost model, four optimization algorithms were employed: Particle Swarm Optimization (PSO), Social Spider Optimization (SSO), Arithmetic Optimization Algorithm (AOA), and Sine Cosine Optimization Algorithm (SCOA). The results from the first data set indicate that the XGBoost model optimized using the Arithmetic Optimization Algorithm (XGB - AOA) achieved the highest accuracy, with R2 values of 0.9962 for the training part and 0.9807 for the testing part. The performance of the developed models was further evaluated using the RMSE, MAE, and VAF indices. The results revealed that the XGBoost model optimized using XGBoost - AOA outperformed other models in terms of accuracy, with RMSE, MAE, and VAF values of 0.0078, 0.0015, and 99.6189 for the training part and 0.0141, 0.0112, and 98.0394 for the testing part, respectively. These findings suggest that XGBoost - AOA is the most accurate model for predicting the pile set-up component.

Reliability-based Structural Design Optimization Considering Probability Model Uncertainties - Part 1: Design Method (확률모델 불확실성을 고려한 구조물의 신뢰도 기반 최적설계 - 제1편: 설계 방법)

  • Ok, Seung-Yong;Park, Wonsuk
    • Journal of the Korean Society of Safety
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    • v.27 no.5
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    • pp.148-157
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    • 2012
  • Reliability-based design optimization (RBDO) problem is usually formulated as an optimization problem to minimize an objective function subjected to probabilistic constraint functions which may include deterministic design variables as well as random variables. The challenging task is that, because the probability models of the random variables are often assumed based on limited data, there exists a possibility of selecting inappropriate distribution models and/or model parameters for the random variables, which can often lead to disastrous consequences. In order to select the most appropriate distribution model from the limited observation data as well as model parameters, this study takes into account a set of possible candidate models for the random variables. The suitability of each model is then investigated by employing performance and risk functions. In this regard, this study enables structural design optimization and fitness assessment of the distribution models of the random variables at the same time. As the first paper of a two-part series, this paper describes a new design method considering probability model uncertainties. The robust performance of the proposed method is presented in Part 2. To demonstrate the effectiveness of the proposed method, an example of ten-bar truss structure is considered. The numerical results show that the proposed method can provide the optimal design variables while guaranteeing the most desirable distribution models for the random variables even in case the limited data are only available.

Development of an Storytelling Instructional Model for promoting problem-solving ability in a Blended Learning Environment (Blended Learning 환경에서 문제해결력 강화를 위한 스토리텔링 교수학습 모형 개발)

  • Kang, Mun-Suk;Kim, Suk-Woo
    • Journal of Fisheries and Marine Sciences Education
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    • v.25 no.1
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    • pp.12-28
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    • 2013
  • The purpose of this study was to develop storytelling Instructional model for promote problem-solving in a Blended learning Environment. To achieve the purpose, the study was performed by dividing into two stages. First, the draft of storytelling Instructional model was proposed by performing a literature survey and a case study. Second, the draft model was applied to the actual work. And the draft was modified and developed to the final model on the basis of the draft model's strength and implemented to 28 students who were the sophomore of child care education department and enrolled the profession class of at S University for 6 weeks. From the implementation result of the model, it was obtained that there was the positive reaction on applying storytelling technique to the beginning stage of learning. Instructional model storytelling consists phases Preparing to perform Storytelling, Building the team and role sharing team, Problem providing, Planning for problem solving, Brend Story structuralization, Cooperative Learning and Problem solving, announcement of the results and evaluating and reflection of general. And then learning supporting components for a facilitator and a learner were prepared for each process. Established in a Blended learning Environment was created based on all-line, how to teach and learning supporting organization. Final Model was suggested as a blueprint for stages actual learning which was consisted of a introductory storytelling part, an main storytelling part and a post storytelling part.

Study on the Accelerated Test Condition of Pneumatic Cylinder (공기압 실린더 가속시험 조건에 대한 연구)

  • Kang, Bo-Sik;Kim, Hyoung-Eui;Gobin, Remi
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.1648-1651
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    • 2007
  • The goal of this paper is to introduce two methods to determine a model for the accelerated factor equation for pneumatic cylinder according to the Black equation shape. The loads consist of working pressure and temperature and we adjust these two parameters to reduce the test time but keeping the true behavior of deterioration. The first part will introduce a method using accelerated factor coming from experimental results to determine the coefficient of the Black equation by the method of the least square theory. The second part will introduce another method based on various conditions of test with the assumption that the effect of temperature and the effect of pressure on the life of pneumatic cylinder are independent. In these two cases, the results are the unknown coefficients of the Black equation.

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Development of Impedance Locus Model for Protective Relay Dynamic Test (보호 계전기 동특성 테스트를 위한 임피던스 궤적 모델 개발)

  • Kim, Su-Nam;Lee, Jae-Gyu;Lee, Myeong-Su;Yu, Seok-Gu
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.51 no.9
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    • pp.451-459
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    • 2002
  • This paper presents a method for modelling of the impedance locus in order to test the protective relay with dynamic. This paper has the two parts, the first part is the configuration of impedance locus with voltage magnitude, total impedance magnitude and angle. And the second part is the control of the locus speed with deviation of two frequencies. The proposed method is applied to two machine equivalent system with PSCAD/EMTDC to show its effectiveness.

A Study on the Possibility of Initial Cost Saving in the New Housing Model Considering Long-life and Constructability - Focused on the Case Analysis with Converting Skeleton and Cladding to New Systems - (장수명화와 시공성을 고려한 새로운 공동주택 모델의 초기 비용절감 가능성 연구 - 구조체와 외장전환 사례분석을 중심으로 -)

  • Kim, Soo-Am;Shin, Sung-Eun;Chung, Joon-Soo;Shon, Young-Jin
    • Journal of the Korean housing association
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    • v.23 no.6
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    • pp.49-59
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    • 2012
  • This study suggested a new model in consideration of long life and constructability of apartment house suggested in the former part. New model suggested the possibility of cost saving based on the idea that people trend to reject because of the recognition that the new model would cost a lot of expense which work as the barrier for the expansion and distribution at the local market so as to prepare the ground for its activation. The Study was aimed at verifying the possibility of cost saving through comparing it with the existing standard apartment house system centered on the skeleton and cladding system among the new structural design models suggested in the former part. Assuming that these existing standard both models should be changed structural design into new model system, the quantity volume, cost and construction period along with the alteration of finished materials between two models were compared altogether. Simultaneously BIM library was built for easy taking-off bill of quantity and consideration of working methodology for construction working cycle, which was translated into construction cost so as to derive the cost of the two subject systems to be counted. Through the analysis, it was concluded that new model would secure variability in the future and constructability along with shortening the construction period (29%) and achieve cost saving (13%) of construction against the those of existing model.

The difference in the slope supported system when excavating twin tunnels: Model test and numerical simulation

  • Liu, Xinrong;Suliman, Lojain;Zhou, Xiaohan;Zhang, Jilu;Xu, Bin;Xiong, Fei;Elmageed, Ahmed Abd
    • Geomechanics and Engineering
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    • v.31 no.1
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    • pp.15-30
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    • 2022
  • Slope stability during the excavation of twin road tunnels is considered crucial in terms of safety. In this research, physical model testing and numerical analysis were used to investigate the characteristics of the settlement (uz) and vertical stresses (σz) along the two tunnel sections. First, two model tests for a (fill-rock) slope were conducted to study the settlement and stresses in presence and absence of slope support (plate support system). The law and value of the result were then validated by using a numerical model (FEM) based on the physical model. In addition, a finite element model with a slope supported by piles (equivalent to the plate) was used for comparison purposes. In the physical model, several rows of plates have been added to demonstrate the capacity of these plates to sustain the slope by comparing excavating twin tunnels in supported and unsupported slope, the results show that this support was effective in the upper part of the slope, while in the middle and lower part the support was limited. Additionally, the plates appear to induce less settlement in several areas of the slope with differing settlement and stress distribution as compared to piles. Furthermore, as a results of the previous mentioned investigation, there are many factors influence the stress and settlement distribution, such as the slope's cover depth, movement during excavation, buried structures such as the tunnel lining, plates or piles, and the interaction between all of these components.

A Study on Speed Improvement of Gate Delay Test Generator for Combinational Circuits (조합회로에 대한 게이트 지연 검사 패턴 생성기의 속도 향상에 관한 연구)

  • 박승용;김규철
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.723-726
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    • 1998
  • Fault dropping is a very important part of test generation process. It is used to reduce test generation time. Test generation systems use fault simulation for the purpose of fault dropping by identifying detectable faults with generated test patterns. Two kinds of delay fault model is used in practice, path delay fault model and gate delay fault model. In this paper we propose an efficient method for gate delay test generation which shares second test vector.

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한중일영 다국어 어휘 데이터베이스의 모형

  • 차재은;강범모
    • Proceedings of the Korean Society for Language and Information Conference
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    • 2002.06a
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    • pp.48-67
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    • 2002
  • This paper is a report on part of the results of a research project entitled "Research and Model Development for a Multi-Lingual Lexical Database". It Is a six-year project in which we aim to construct a model of a multilingual lexical database of Korean, Chinese, Japanese, and English. Now we have finished the first two-year stage of the project In this paper, we present the goal of the project, the construction model of items in the lexical database, and the possible (semi-)automatic methods of acquisition of lexical information. As an appendix, we present some sample items of the database as an i1lustration.

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