• Proceedings of the PSK Conference
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• 2002.04a
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• pp.220.2-220.2
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• 2002

• Journal of ILASS-Korea
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• v.28 no.1
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• pp.1-9
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• 2023

In the cylinder of gasoline direct injection engines, the spray targeting from injectors is of great significance for fuel consumption and pollutant emissions. The automotive industry is putting a lot of effort into improving injector targeting accuracy. To improve the targeting accuracy of injectors, it is necessary to develop models that can predict the spray targeting positions. When developing spray targeting models, the most used technique is computational fluid dynamics (CFD). Recently, due to the superiority of machine learning in prediction accuracy, the application of machine learning in this field is also receiving constant attention. The purpose of this study is to build a machine learning model that can accurately predict spray targeting based on the design parameters of injectors. To achieve this goal, this study firstly used laser sheet beam visualization equipment to obtain many spray cross-sectional images of injectors with different parameters at different injection pressures and measurement planes. The spray images were processed by MATLAB code to get the targeting coordinates of sprays. A total of four models were used for the prediction of spray targeting coordinates, namely ANN, LSTM, Conv1D and Conv1D & LSTM. Features fed into the machine learning model include injector design parameters, injection conditions, and measurement planes. Labels to be output from the model are spray targeting coordinates. In addition, the spray data of 7 injectors were used for model training, and the spray data of the remaining one injector were used for model performance verification. Finally, the prediction performance of the model was evaluated by R² and RMSE. It is found that the Conv1D&LSTM model has the highest accuracy in predicting the spray targeting coordinates, which can reach 98%. In addition, the prediction bias of the model becomes larger as the distance from the injector tip increases.

• Korean Journal of Applied Biomechanics
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• v.33 no.2
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• pp.45-51
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• 2023

Objective: The aim of this study was to examine the effect of strength training targeting medial quadriceps/hamstrings and non-targeting strength training on dynamic balance. Method: A total of 51 healthy subjects were randomly assigned to control, targeting strength training, or non-targeting training groups. To measure the dynamic balance, the star excursion balance test (SEBT) was performed before and after training. The SEBT parameters were compared using repeated measures ANOVA, and post-hoc paired t test at a significance level of 0.05. Results: Greater anterior (p= .011), anteromedial (p= .001), medial (p< .001), lateral (p< .001), and anterolateral (p= .001) reach distances were found between pre- and post-training in the strength training targeting medial thigh muscles group. Only greater lateral reach distance was found after non-targeting strength training (p= .029). In addition, no differences were found for any SEBT scores in the control group. Conclusion: Strength training targeting medial quadriceps and hamstrings can improve the dynamic balance, thereby it positively affected in lower extremity injury risk, whereas non-targeting strength training rarely changes the dynamic balance.

• Korea Trade Review
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• v.47 no.5
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• pp.75-93
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• 2022

Purchasing Power Parity (hereafter, PPP) means the purchasing power of two currencies is the same when one is converted into the other one. According to previous studies on PPP, as the volatility of the real exchange rate is smaller, PPP may be more likely to hold. Since New Zealand adopted the inflation targeting policy in December 1989, many countries started to adopt it as their monetary policy frame. Previous studies on inflation targeting found that inflation targeting policy has positive effects on not only achieving price stability but also reducing the volatility of nominal/ real exchange rates. Therefore, in this study, I explored whether inflation targeting policy has positive effects on purchasing power parity subject to 19 OECD countries, applying an Exponential Smooth Transition Autoregressive (ESTAR) model during the sample periods, from 1974:Q1 to 2019:Q4. Based on the ESTAR estimate results, I found limited favorable evidence of PPP for only two countries- England and Switzerland- among 9 inflation targeters, compared to non-inflation targeters, and also I found that favorable evidence of PPP only for these two countries among 9 inflation targeters during post-inflation targeting, but not during pre-inflation targeting. These findings imply that the positive effects of inflation targeting on PPP may be questionable unlike Ding and Kim (2012) and Kim (2014)'s study.

• BMB Reports
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• v.50 no.11
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• pp.554-559
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• 2017

MicroRNAs (miRNAs) are ~22nt-long single-stranded RNA molecules that form a RNA-induced silencing complex with Argonaute (AGO) protein to post-transcriptionally downregulate their target messenger RNAs (mRNAs). To understand the regulatory mechanisms of miRNA, discovering the underlying functional rules for how miRNAs recognize and repress their target mRNAs is of utmost importance. To determine functional miRNA targeting rules, previous studies extensively utilized various methods including high-throughput biochemical assays and bioinformatics analyses. However, targeting rules reported in one study often fail to be reproduced in other studies and therefore the general rules for functional miRNA targeting remain elusive. In this review, we evaluate previously-reported miRNA targeting rules and discuss the biological impact of the functional miRNAs on gene-regulatory networks as well as the future direction of miRNA targeting research.

• East Asian Economic Review
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• v.22 no.4
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• pp.531-555
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• 2018

This article aims to review the monetary policy rule under inflation targeting framework focusing on Mongolia. The empirical analysis estimates the policy reaction function to see if the inflation targeting has been linked with a monetary policy rule emphasizing on inflation stabilization since its adoption in 2007. The study contributes to the literature by examining the linkage between Mongolian monetary policy rule and inflation targeting directly and thoroughly for the first time and also by taking into account a recent progress in the inflation targeting framework toward forward-looking mode. The main findings were: the Mongolian current monetary policy rule under inflation targeting is characterized as inflation-responsive rule with forward-looking manner (one quarter ahead); the inflation responsiveness is, however, weak enough to be pro-cyclical to inflation pressure; and the rule is also responsive to exchange rate due to the "fear of floating", which weakens the policy reaction to inflation and output gap.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.300.1-300.1
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• 2003

Salmon calcitonin (sCT) is a therapeutic polypeptide hormone consisting of 32 amino acids (3432 Da). As with other bioactive peptide therapeutics, however, therapeutic use of sCT has been limited due to the problems of short circulating half-life and rapid proteolytic degradation. To get over this problem, the three positional isomers of mono-PEGylated sCT were prepared and among these, the best drug candiate for nasal application was chosen. (omitted)

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.268.2-269
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• 2000

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.269.2-270
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• 2000

• Proceedings of the PSK Conference
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• 2000.04a
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• pp.199.2-199.2
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• 2000