• Journal of Distribution Science
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• v.11 no.10
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• pp.63-72
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• 2013

Purpose - This study analyzes the relationship and dynamic interactions between stock price index, interest rate, price index, and housing price indices using Korean monthly data from 2000 to 2013, based on a VAR model. This study also examines Granger causal relationships among these variables in order to determine whether the time series of one is useful in forecasting another, or to infer certain types of causal dependency between stochastic variables. Research design, data, and methodology - We used Korean monthly data for all variables from 2000: M1 to 2013: M3. First, we checked the correlations among different variables. Second, we conducted the Augmented Dickey-Fuller (ADF) test and the co-integration test using the VAR model. Third, we employed Granger Causality tests to quantify the causal effect from time series observations. Fourth, we used the impulse response function and variance decomposition based on the VAR model to examine the dynamic relationships among the variables. Results - First, stock price Granger affects interest rate and all housing price indices. Price index Granger, in turn, affects the stock price and six metropolitan housing price indices. However, none of the Granger variables affect the price index. Therefore, it is the stock markets (and not the housing market) that affects the housing prices. Second, the impulse response tests show that maximum influence on stock price is its own, and though it is influenced a little by interest rate, price index affects it negatively. One standard deviation (S.D.) shock to stock price increases the housing price by 0.08 units after two months, whereas an impulse shock to the interest rate negatively impacts the housing price. Third, the variance decomposition results report that the shock to the stock price accounts for 96% of the variation in the stock price, and the shock to the price index accounts for 2.8% after two periods. In contrast, the shock to the interest rate accounts for 80% of the variation in the interest rate after ten periods; the shock to the stock price accounts for 19% of the variation; however, shock to the price index does not affect the interest rate. The housing price index in 10 periods is explained up to 96.7% by itself, 2.62% by stock price, 0.68% by price index, and 0.04% by interest rate. Therefore, the housing market is explained most by its own variation, whereas the interest rate has little impact on housing price. Conclusions - The results of the study elucidate the relationship and dynamic interactions among stock price index, interest rate, price index, and housing price indices using VAR model. This study could help form the basis for more appropriate economic policies in the future. As the housing market is very important in Korean economy, any changes in house price affect the other markets, thereby resulting in a shock to the entire economy. Therefore, the analysis on the dynamic relationships between the housing market and economic variables will help with the decision making regarding the housing market policy.

• Journal of Biosystems Engineering
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• v.32 no.6
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• pp.416-421
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• 2007

Physical damage to fruits and vegetables caused by shock degrades the value of product in the fresh market. In order to design a product/packaging system to protect the product, the G-factor to the product that causes shock damage needs to be determined. The shock fragility of organisms such as fruits with a concept correspondent to the G-factor of industrial products was calculated and we defined the allowable bio-shock fragility index as the value divided peak acceleration that was generated in safe drop height by standard acceleration of gravity. We did modeling for safe drop hight that would prevent fruits from damage by drop tests and tried to estimate the allowable bio-shock fragility index of pears and apples for optimum packaging design. The bio-shock fragility index of pears was in the range of $0.74{\sim}2.29\;G$, while apples had a slightly higher value than that of pears, of $0.51{\sim}2.98\;G$. This result shows accordance with the general fact that apples have a firmer structure and get less damage from the same impact. Based on this result, it is possible to create an optimum packaging design by providing a damage standard by impact.

• Journal of Trauma and Injury
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• v.35 no.3
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• pp.181-188
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• 2022

Purpose: Inferior vena cava (IVC) collapse is related to hypovolemia. Sonography has been used to measure the IVC diameter, but there is variation depending on the skill of the operator and it is difficult to obtain accurate measurements in patients who have a large amount of intestinal gas or are obese. As a modality to obtain accurate measurements, we measured the diameters of the IVC and aorta on trauma computed tomography scans and investigated the correlation between the IVC to aorta ratio and the shock index in blunt trauma patients. Methods: We retrospectively analyzed the medical records of 588 trauma patients who were transferred to the regional trauma center (level 1) of Wonkang University Hospital from March 2020 to February 2021. We included trauma patients 18 years or older who met the trauma activation criteria and underwent trauma computed tomography scans with intravenous contrast within 40 minutes of admission. The shock index was calculated from vital signs before trauma computed tomography scan, and measurements of the anteroposterior diameter of the IVC (AP), the transverse diameter of the IVC (T), and aorta were made 10 mm above the right renal vein in the venous phase. Results: Overall, 271 patients were included in this study, of whom 150 had a shock index ≤0.7 and 121 had a shock index >0.7. The T to AP ratio and AP to aorta ratio were significantly different between groups. Cutoffs were identified for the T to AP ratio and AP to aorta ratio (2.37 and 0.62, respectively) that produced clinically useful sensitivity and specificity for predicting a shock index >0.7, demonstrating moderate accuracy (T to AP ratio: area under the curve, 0.71; sensitivity, 59%; specificity, 87% and AP to aorta ratio: area under the curve, 0.70; sensitivity, 55%; specificity, 91%). Conclusions: The T to AP ratio and AP to aorta ratio are useful for predicting hemorrhagic shock in trauma patients.

• International journal of steel structures
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• v.18 no.5
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• pp.1710-1722
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• 2018

Investigating remained damages from terrible earthquakes, it could be concluded that some events including explosion because of defect and failure in the building mechanical facilities or caused by gas leak, firing, aftershocks, etc., which are occurred during or a few time after the earthquake, will increase the effects of damages. In this paper, by introducing a complete risk analysis which included direct and indirect risks for earthquake (the main shock) and aftershock, the corresponding robustness index was created that called as "robustness index sequential critical events risk-based". One of the main properties of the intended robustness index is using progressive collapse percentage in its evaluation. Then, in a numerical example for a 4-storey moment resisting steel frame structure, a method is presented for obtaining all effective parameters in robustness index evaluation based on the intended risk and at last its results were reported.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.1
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• pp.36.4-37
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• 2017

Although most of observed properties of giant radio relics detected in the outskirts of galaxy clusters could be explained by relativistic electrons accelerated at merger-driven shocks, a few significant puzzles remain. In some relics the shock Mach number inferred from X-ray observations is smaller than that estimated from radio spectral index. Such a discrepancy could be understood, if either the shock Mach number is nder-estimated in X-ray observation due to projection effects, or if pre-existing electrons with a flat spectrum are re-accelerated by a weak shock, retaining the flat spectral form. In this study, we explore these two scenarios by comparing the results of shock acceleration simulations with observed features of the so-called Toothbrush relic in the merging cluster 1RXS J060303.3. We find that both models could reproduce reasonably well the observed radio flux and spectral index profiles and the integrated radio spectrum. Either way, the broad transverse relic profile requires additional post shock electron acceleration by downstream turbulence.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.4
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• pp.1-9
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• 2011

Hemorrhagic shock is a clinically widespread syndrome characterized by inadequate oxygenation and supply. It is important to diagnose hemorrhagic shock in its early stage for improving treatment effects and survival rate. However, an accurate diagnosis and treatment could be delayed in the early stage of hemorrhagic shock by evaluating only vital signs such as heart rate and blood pressure. There have been many studies for the early diagnosis of hemorrhagic shock, reporting that lactate concentration and perfusion were useful variables for tissue hypoxia and metabolic acidosis. In this study, we measured both perfusion using a laser Doppler flowmeter and lactate concentration from the volume controlled hemorrhagic shock using rats. We also proposed a new shock index which was calculated by dividing lactate concentration by perfusion for early diagnosis. As a result of the survival prediction by the proposed index with the receiver operating characteristic curve method, the sensitivity, specificity, and accuracy of survival were 90.0, 96.7 and 94.0%, respectively. The proposed index showed the fastest significant difference among the other parameters such as blood pressure and heart rate. It could offer early diagnosis and effective treatment for human hemorrhagic shock if it is applicable to humans.

• Journal of The Korean Society of Emergency Medicine
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• v.29 no.6
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• pp.616-623
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• 2018

Objective: The shock index (SI), as a trauma triage tool, is a capable clinical indicator of hemodynamic instability and hypovolemic shock, but the conception of SI is contradictory to shock. The reverse shock index (RSI) was introduced recently, but its utility has not been sufficiently proven. Methods: This study examined the RSI utility by evaluating the procedures performed at an emergency department (ED) and the associated outcomes when the RSI is used alone or in combination with the Korean Triage and Acuity Scale (KTAS). This was a retrospective study conducted by including data of 4,789 adult trauma patients for a year. The clinical variables, procedures performed on patients, and outcomes were investigated. The median RSI was 0.9 in the RSI<1 group. Results: Patients in the RSI<1 group had a higher odds of requiring procedures at the ED and for experiencing worse outcomes: intubation (odds ratio [OR], 5.4; 95% confidence interval [CI], 2.3-13.1; P<0.001), chest tube insertion (OR, 6.5; 95% CI, 0.4-111.84; P<0.001), use of emergency drugs (OR, 3.6; 95% CI, 1.5-8.5; P<0.001), circulatory support (OR, 5.4; 95% CI, 2.3-12.9; P<0.001), intensive care unit admission (OR, 3.5; 95% CI, 1.8-6.8; P<0.001), and mortality during the ED stay (OR, 20.4; 95% CI, 5.5-75.7; P<0.001). In the group with KTAS 1-3, trends similar to those in the RSI<1 group were observed. Patients with RSI<1 had more severe injuries and poorer outcomes than those with $RSI{\geq}1$, regardless of whether the RSI was used alone or in combination with KTAS. Conclusion: RSI can provide an appropriate triage with concurrent KTAS use.

• Asian Journal of Innovation and Policy
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• v.12 no.3
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• pp.323-344
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• 2023

This study investigates the resilient structural characteristics of a region by assessing the impact of the financial crisis. Utilizing panel data at the prefecture level for metropolitan cities across pre-shock (2006-2008), shock (2009), and post-shock (2010-2019) periods, we calculated an employment resilience index by combining the resistance and recovery indices. The panel logit regression measures the influences of the region's industrial structure and external economic factors in response to the global financial crisis. The results revealed that the diversity index of industries contributed to the post-shock recovery bounce-back. Additionally, the presence of large firms and industrial clusters within the region positively contributed to economic resilience. The specialization and the proportion of manufacturing industries showed negative effects, suggesting that regions overly reliant on manufacturing-centered specialization might be vulnerable to external shocks. Furthermore, excessive capital outflows for market expansion were found to have a detrimental impact on regional economic recovery.

• Journal of the Korean Data and Information Science Society
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• v.25 no.1
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• pp.65-76
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• 2014

Housing prices are influenced by external shock factors such as real estate policy or economy. Thus, the intervention effect is important for the development of forecasting model for housing price index. In this paper, we examined the degree of effective power of external shock factors for forecasting housing price index and analyzed time series models for efficient forecasting of housing price index. It is shown that intervention models are better than other models in forecasting results using real data based on the accuracy criteria.

• International Area Studies Review
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• v.20 no.3
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• pp.123-144
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• 2016

This paper investigates the linkages between returns both in foreign exchange and stock markets, and uncertainties in two markets using daily data for the period of 16 July 2004 to 30 June 2014 in Nepalese economy. Four hypotheses are tested about how uncertainty influences the stock index and exchange rates. From the empirical results, a bivariate EGARCH-M model is the best to explain the volatility in the two markets. There is a negative relationship from the exchange rates return to stock price return. Empirical results do provide strong empirical confirmation that negative effect of stock index uncertainty and positive effect of exchange rates uncertainty on average stock index. GARCH-in-mean variables in AR modeling are significant and shows that there is positive effect of exchange rates uncertainty and negative effect of stock index uncertainty on average exchange rates. Stock index shocks have longer lived effects on uncertainty in the stock market than exchange rates shock have on uncertainly in the foreign exchange market. The effect of the last period's shock, volatility is more sensitive to its own lagged values.