• Journal of the Korean Institute of Rural Architecture
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• v.24 no.4
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• pp.25-32
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• 2022

The purpose of this study is to provide design guidelines necessary for creating disability-friendly campuses. To this end, a literature survey and a survey on the current educational welfare facilities for disabled college students were conducted. The fact-finding survey was conducted in writing and visiting evaluations on 19 campuses located in Gangwon-do(province). The results of this study are summarized as follows: 1) The college enrollment rate of the disabled has doubled since 2000, but it was found to be half of the enrollment rate based on school enrollment, and the number of students who gave up in the middle is increasing. This is due to an obstacle in the learning environment, so it is necessary to improve welfare facilities. 2) As a result of evaluating the status of educational welfare support for students with disabilities, it was found that the overall evaluation result was improved, but the absolute evaluation result was less than 70%, and it was not improved. 3) As a result of evaluating the actual conditions of the intermediate facilities, indoor facilities, sanitary facilities, guidance and other facilities, and unit spaces, it is necessary to expand and improve them due to the lack of disabled parking marks, continuity of access roads, pedestrian safety passages, lifts, and rest areas for the disabled.

• Journal of Korean Association for Spatial Structures
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• v.23 no.4
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• pp.81-88
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• 2023

Numerous factors contribute to the deterioration of reinforced concrete structures. Elevated temperatures significantly alter the composition of the concrete ingredients, consequently diminishing the concrete's strength properties. With the escalation of global CO2 levels, the carbonation of concrete structures has emerged as a critical challenge, substantially affecting concrete durability research. Assessing and predicting concrete degradation due to thermal effects and carbonation are crucial yet intricate tasks. To address this, multiple prediction models for concrete carbonation and compressive strength under thermal impact have been developed. This study employs seven machine learning algorithms-specifically, multiple linear regression, decision trees, random forest, support vector machines, k-nearest neighbors, artificial neural networks, and extreme gradient boosting algorithms-to formulate predictive models for concrete carbonation and thermal impact. Two distinct datasets, derived from reported experimental studies, were utilized for training these predictive models. Performance evaluation relied on metrics like root mean square error, mean square error, mean absolute error, and coefficient of determination. The optimization of hyperparameters was achieved through k-fold cross-validation and grid search techniques. The analytical outcomes demonstrate that neural networks and extreme gradient boosting algorithms outshine the remaining five machine learning approaches, showcasing outstanding predictive performance for concrete carbonation and thermal effect modeling.

• Journal of Ocean Engineering and Technology
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• v.38 no.1
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• pp.18-29
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• 2024

Waves are a complex phenomenon in marine and coastal areas, and accurate wave prediction is essential for the safety and resource management of ships at sea. In this study, three types of machine learning techniques specialized in nonlinear data processing were used to predict the waves of Korea waters. An optimized algorithm for each area is presented for performance evaluation and comparison. The optimal parameters were determined by varying the window size, and the performance was evaluated by comparing the mean absolute error (MAE). All the models showed good results when the window size was 4 or 7 d, with the gated recurrent unit (GRU) performing well in all waters. The MAE results were within 0.161 m to 0.051 m for significant wave heights and 0.491 s to 0.272 s for periods. In addition, the GRU showed higher prediction accuracy for certain data with waves greater than 3 m or 8 s, which is likely due to the number of training parameters. When conducting marine and offshore research at new locations, the results presented in this study can help ensure safety and improve work efficiency. If additional wave-related data are obtained, more accurate wave predictions will be possible.

• Steel and Composite Structures
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• v.52 no.1
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• pp.1-14
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• 2024

This paper introduces a system allows for seismic isolation of the pallet from the rack in the down-aisle direction, occupies minimal vertical space (5 cm) and ±7.5 cm of deformation range. A conceptual model of the isolation system is presented, leading to a constitutive equation governing its behavior. A first experimental campaign studying the response of the isolation system's components was conducted to calibrate the parameters of its constitutive equation. A second experimental campaign evaluated the response of the isolation system with mass placed on it, subjected to cyclic loading. The results of this second campaign were compared with the numerical predictions using the pre-calibrated constitutive equation, allowing a double-blind validation of the constitutive equation of the isolation system. Finally, a numerical evaluation of the isolation system subjected to a synthetic earthquake of one component. This evaluation allowed verifying attributes of the proposed isolation system, such as its self-centering capacity and its effectiveness in reducing the absolute acceleration of the isolated mass and the shear load transmitted to the supporting beams of the rack.

• Korean Journal of Clinical Pharmacy
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• v.19 no.2
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• pp.81-88
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• 2009

Objectives: With more and more health economic evaluations being performed in many countries, the question of whether the results from the foreign studies can be transferred to other country is becoming important. The objective of this study was to conduct a case study using three transferability diagnosis tools for economic evaluation on rheumatoid arthritis. Methods: Three diagnosis tools were used to assess transferability: Welte's tool, Boulenger's and Urdahl's. Five researchers who have experience on economic evaluation made consensus on the evaluation through the semi-delphi method. Results: With Welte's tool, absolute and relative prices in healthcare, practice variation, health-status preference, productivity and work-loss time were evaluated as biased. The transferability information score by Boulenger's was 85.9%, which means qood quality reporting. In case of Urdahl's, research questions were well defined and reporting was transparent and explicitly stated. However, both the relevance of data inputs to Korea and robustness of model were relatively low. In conclusion the UK study on rheumatoid arthritis could be partially transferable to Korea, and will need modeling-based adjustments.

• Archives of design research
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• v.3 no.1
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• pp.17-33
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• 1990

Evaluation plays an essential role in design activity. Many theorist have agreed that designing involves problem solving or decision making. In evaluation, designers attempt to determine the value of a particular proposal arrived at by synthesis. And the results of designing, the product, is evaluated twice, objectively and subjectively.Alternatives in $$\mu$ti-objective decision problems generally possess numerous attributes by which they can be described and compared. The evaluation factors include all attributes that have levels specified by quantitative and qualitative objectives. However since qualitiative factors are difficult to quantify as $$\mu$eral estmates, these factors have tended to be ignored without regard for their importance to human content. Therefore we need some study that convert qualitative attributes into quantitative scale values. Following to Thurstone' s Psychological scaling methods (The method of successive intervals), attribute values of TV set are assigned by rating scale methods. The method of successive intervals, like the method of equal-appearing intervals, requires but a single judgement from each subject for each statement to be scaled. It is, therefore, a convinient method to use when the number of to be scaled is large. We make the assumtion that those cu$$\mu$ative proportion distributions are normal for each statement when they are projected on the unknown psychological continuum. In this study, we have determined the scale values of 42 statements of TV set by the method of successive intervals. Then we can apply a test of internal consistency similar to that used with the method of paired comparisons. We have as our absolute average deviation, -1.748/252= -0.0069. We have reason to believe that our scale values are consistent with the empirical data, because these discrepanicies are very small.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.1
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• pp.29-36
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• 2015

Exact comparisons of the thermal conductivities of the base fluid and a nanofluid are very important in the early stages of nanofluid development. A simple procedure of measuring the thermal conductivity of the two fluids by the transient hot wire method and numerically dividing these values is used for this purpose. However, because the experiments are not performed simultaneously and the physical properties of the measurement system are sometimes not properly known, large errors are incurred during the evaluation process. This article proposes a new apparatus for thermal conductivity comparison where the working principle is mainly based on relative measurement rather than absolute measurement. The measuring circuit and data processing steps are explained in detail; a validation test was performed using the well-known glycerine and engine oil.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.6
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• pp.23-35
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• 2009

This study proposes a methodology for estimating representative section travel times using individual vehicle travel information under the ubiquitous transportation environment (UTE). A novel approach is to substantialize a concept of dynamic node-links in processing trajectory data. Also, grouping vehicles was conducted to obtain more reliable travel times representing characteristics of individual vehicle travels. Since the UTE allows us to obtain higher accuracy of vehicle positions, travel times for each lane can be estimated based on the proposed methodology. Evaluation results show that less than 10% of mean absolute percentage error was achievable with 20% of probe vehicle rate. It is expected that outcome of this study is useful for providing more accurate and reliable traffic information services.

• Korean Journal of Veterinary Research
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• v.50 no.3
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• pp.179-185
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• 2010

The present study was undertaken to establish reference values for the composition blood lymphocyte populations and compare forty three Hanwoo neonatal calves (KC) with twenty one Holstein calves (HC) by blood cell count and immunophynotying. The percentages of CD2+, CD4+, CD8+, CD26+, ACT2+, MHC class, MHC class II and WC1+ T cells, B cells were determined by flow cytometry. The number of lymphocyte and monocyte in HC were higher than those of KC. However, the number of neutrophils was higher in HC than KC. The proportions of CD2+, CD4+, CD8+, MHC class, and WC1+ lymphocytes remained relatively stable during the study period, while there was a moderate increase in the relative percentage of CD26+, ACT2+, MHC class II and B cell from birth to approximately 3 weeks of age. Marked differences in the relative proportions of the lymphocyte subpopulations were noted between the individual calves. The present study shows that the T-cell subpopulations are present in peripheral blood of KC at levels comparable with HC, while the MHC class II and B cell population of KC increases significantly with age. The absolute number of WBC in KC was due to the decrease of absolute number of neutrophil rather than the increase of lymphocyte. The results indicated that KC have significantly higher number of neutrophils, and proportion of MHC class II and B cell than HC.

• Korean Journal of Remote Sensing
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• v.32 no.6
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• pp.589-601
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• 2016

Sea surface currents were estimated by applying the Maximum Cross Correlation (MCC), Zero-mean Sum of Absolute Distances (ZSAD), and Zero-mean Sum of Squared Distances (ZSSD) algorithms to Himawari-8/Advanced Himawari Imager (AHI) thermal infrared channel data, and the comparative analysis was performed between the results of these algorithms. The sea surface currents of the Kuroshio Current region that were retrieved using each algorithm showed similar results. The ratio of errors to the total number of estimated surface current vectors had little difference according to the algorithms, and the time required for sea surface current calculation was reduced by 24% and 18%, relative to the MCC algorithm, for the ZSAD and ZSSD algorithms, respectively. The estimated surface currents were validated against those from satellite-tracked surface drifter and altimeter data, and the accuracy evaluation of these algorithms showed results within similar ranges. In addition, the accuracy was affected by the magnitude of brightness temperature gradients and the time interval between satellite image data.