• Journal of The Korean Society of Integrative Medicine
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• v.10 no.4
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• pp.145-151
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• 2022

Purpose : Stroke patients exhibit abnormal walking patterns such as slow walking speed and asymmetrical walking values. The recovery of symmetrical walking in the stance phase using a treadmill means improvements in walking speed and asymmetrical walking. The purpose of this research was to investigate the effect of unilateral step treadmill training (USTT) on gait speed and the recovery of symmetrical walking in chronic stroke patients. Methods : Fifteen patients (11 men and 4 women) with chronic stroke participated in this study. The 10-meter walk test (10MWT) and GAITRite system were used to determine the intervention-related changes in gait speed and symmetrical walking values such as non-paretic step length (NSL), non-paretic step time (NST), paretic single-support time (PSST), step length asymmetry (SLA), and step time asymmetry (STA) after USTT. All participants completed USTT and underwent measurements at 3 different times: at pretest, posttest, and the follow-up test. Repeated-measures analysis of variance was used to compare walking speed and asymmetrical walking values. The statistical significance level was set at p<.05. Results : Walking speed by 10MWT (p<.05) showed significant improvements after USTT as follows: at pretest and posttest (p<.05), posttest and follow-up test (p<.05), and pretest and follow-up test (p<.05). Recovery of symmetrical walking patterns such as NSL (p<.05), NST (p<.05), and SLA (p<.05) were observed after USTT. However, no significant improvements were found in PSST (p>.05) and STA (p>.05) in symmetrical gait. Conclusion : This study suggests that USTT may have a positive effect on walking speed and symmetrical walking patterns in chronic stroke patients. Thus, this study contributes to the existing knowledge about the usefulness of USTT for the effective management of patients with chronic stroke. Further studies are needed to generalize these findings.

• The Korean Journal of Financial Management
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• v.20 no.1
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• pp.191-212
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• 2003

Recently, there is a growing body of literature that suggests that information inefficiency is one of the causes of the asymmetric volatility. If this explanation for the asymmetric volatility is appropriate, then innovations, such as the introduction of futures, may be expected to impact the asymmetric volatility of stock market. As transaction costs and margin requirements in the futures market are lower than those in the spot market, new information is transmitted to futures prices more quickly and affects spot prices through arbitrage trading with spots. Also, the merit of the futures market may attract noise traders away from the spot market to the futures market. This study examines the impact of futures on the asymmetry of stock market volatility. If the asymmetric volatility is significant lower post-futures and exist in the futures market, it has validity that the asymmetric volatility is caused by information inefficiency in the spot market. The data examined are daily logarithmic returns on KOSPI 200 stock price index from January 4, 1993 to December 26, 2000. To examine the existence of the asymmetric volatility in the futures market, logarithmic returns on KOSPI 200 futures are used from May 4, 1996 to December 26, 2000. We used a conditional mode of TGARCH(threshold GARCH) of Glosten, Jagannathan and Runkel(1993). Pre-futures the spot market exhibits significant asymmetric responses of volatility to news and post-futures asymmetries are significantly lower, irrespective of bear market and bull market. The results suggest that the introduction of stock index futures has an effect on the asymmetric volatility of the spot market and are inconsistent with leverage being the sole explanation of asymmetry. However, it is found that the volatility of futures is not so asymmetric as expected.

• Health Policy and Management
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• v.25 no.1
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• pp.53-62
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• 2015

Background: Supplier induced demand (SID) indicates the case when doctors increase the demand of the patients, following their (physicians') own best interests rather than patients'. This may occur when asymmetry of information exists between suppliers and consumers. This study aims to confirm whether SID exists in the Korean setting, particularly by dividing SID into both 'induced demand effect' and 'availability effect.' Methods: Induced demand effect and availability effect are differentiated following Carlsen & Grytten's theoretical frame which divides doctor density regions into high and low ones. Results: Positive correlation between doctors' density and utilization of their services was found, which could be interpreted as 'availability effect.' Conclusion: The result suggests that additional medical use for additional doctor, particularly in the area of low doctor density, can be interpreted to occur to meet the basic medical need of the people rather than as a result of unnecessary induced demand. It is important to make more medical doctors provided and to distribute them appropriately across the region in such a country like Korea where doctor's density is relatively low.

• 산업혁신연구
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• v.34 no.2
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• pp.1-30
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• 2018

This study analyzes empirically the effects of financial cash flows and operating cash flows on R&D investment of firms listed on Korea Exchange. The main results of this study can be summarized as follows. Financial cash flows have a larger positive effect on R&D investment than operating cash flows do, implying that firms use more financial cash flows than operating cash flows for financing R&D investment that has information asymmetry problems. This results suggest that improving financial cash flows enhance R&D investment by increasing the predictability of cash flows and decreasing the volatility of cash flows by decreasing financial leverage. Financially constrained firms use much more financial cash flows than operating cash flows for financing R&D investment that has information asymmetry problems. Financial constraints are measured by proxy variables such as firm size and Hadlock and Pierce's(2010) HP index. This results suggest that improving financial cash flows is more important than operating cash flows for financing R&D investment of financially constrained firms. Moreover, firms use more financial cash flows for financing asset-counted R&D investment than for financing cost-counted R&D investment. Asset-counted R&D investment is counted in intangible assets on the Statement of Financial Position, whereas cost-counted R&D investment is counted in cost on the Income Statement. In conclusion, even after controlling for adjustment costs associated with R&D investment and the endogeneity problems of cash flow variables as well as other characteristic variables, the results show that financially constrained firms use much more financial cash flows than operating cash flows for financing R&D investment that has information asymmetry problems. Overall, this finding suggests that information asymmetry and financial constraints problems are likely to co-exist in financing R&D investment. This finding also contributes to the extant literature that examines investment-cash flow sensitivity by showing that financial cash flows have a larger effect on R&D investment rather than operating cash flows.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.55-65
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• 2020

The objective of this study is to investigate how investors in the Stock Exchange of Thailand practically trade in response to a magnitude of profits and losses, given a discussion of the widely well-known behavioral explanation, so called as the disposition effect. We provide empirical evidence of an existence of the V-shaped disposition effect, which has been recently found in several advanced equity markets. By adopting the methodology suggested by An's (2016) and Fama and Macbeth (1973), we document that stock return patterns in relation to aggregate unrealized gains and losses of investors are consistent with the V-shaped selling schedule, given an increase in unrealized gains and losses over the period of January 1996 to December 2015. The effect of unrealized gains is stronger than that of unrealized losses and this asymmetry underlies the existence of the V-shaped disposition effect in the Thai equity market. Interestingly, the effect of the V-shaped selling schedule is strongest over the short-term holding time horizon. Last but not the least, stocks for which investors have large unrealized gains and losses outperform in the following month and the long-short trading strategy, based on this premise, generates the average 1.7% monthly (equivalent to 20.0% per year) abnormal return.

• International Journal of Vascular Biomedical Engineering
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• v.1 no.2
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• pp.20-29
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• 2003

A new treatment for coronary artery occlusive disease is being developed in which a shunt or conduit is placed directly connecting the left ventricle with the diseased artery at a point distal to the obstruction. To aid in assessing and optimizing its benefit, a computational model of the cardiovascular system was developed and used to explore various design conditions. Simulation results indicate that in complete LAD occlusion, flow can be returned to approximately 65% of normal if the conduit resistance is equal for forward and reverse flow, increasing to 80% in the limit in which backflow resistance is infinite. Increases in flow rate produced by asymmetric flow resistance are considerably enhanced in the case of a partial LAD obstruction since the primary effect of resistance asymmetry is to prevent leakage back into the ventricle("steal") during diastole. Increased arterial compliance has little effect on net flow with a symmetric shunt, but leads to considerable augmentation when the resistance is asymmetric. These results suggest that an LV-LAD conduit will be beneficial when stenosis resistance(Rst) > 27 PRU if resistance is symmetric.

• KDI Journal of Economic Policy
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• v.38 no.3
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• pp.79-106
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• 2016

This paper investigates the effectiveness of public credit guarantee programs and interest-support programs for SMEs (small and medium enterprises). First, assuming that there is an imperfect information structure in the SME loan market, we analyze how SME support financial programs affect the corporate decisions made by SMEs with regard to default or loan sizes. In addition, this paper theoretically computes the optimal levels of credit guarantee amounts and the interest-support spread under equilibrium with imperfect information in a competitive loan market. Second, the paper empirically analyzes the continuous policy-treatment effect with the GPS (generalized propensity score) method. In particular, we consider the ratio of guaranteed debt to the total debt as a continuous policy treatment. The empirical results show that marginal effects of a credit guarantee on SMEs' productivity, profitability, and growth potential decrease with the ratio of guaranteed debt to the total debt. In addition, the average effect of a credit guarantee is maximized when this ratio is at 50% to 60%.

• Communications for Statistical Applications and Methods
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• v.21 no.4
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• pp.335-347
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• 2014

This paper employs dynamic conditional correlation (DCC) model to examine time-varying comovement in the Korean stock market with a focus on the financial industry. Analyzing the daily returns of KOSPI 200 eight sector indices from January 2008 to December 2013, we find that stock market correlations significantly increased during the GFC period. The Financial Sector had the highest correlation between the Constructions-Machinery Sector; however, the Consumer Discretionary and Consumer Staples sectors indicated a relatively lower correlation between the Financial Sector. In terms of model fitting, the DCC with t distribution model concludes as the best among the four alternatives based on BIC, and the estimated shape parameter of t distribution is less than 10, implicating a strong tail dependence between the sectors. We report little asymmetric effect in correlation dynamics between sectors; however, we find strong asymmetric effect in volatility dynamics for each sector return.

• Wind and Structures
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• v.5 no.2_3_4
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• pp.359-368
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• 2002

This paper describes a CFD investigation into the flow over the cab of a bluff-fronted lorry. Several different simulations were undertaken, using the commercial codes: CFX, Fluent and PowerFLOW. Using the $k-{\varepsilon}$ turbulence model, the flow over the cab was symmetric, however, using more accurate turbulence models such as the RNG $k-{\varepsilon}$ model or the Reynolds Stress Model, the flow was asymmetric. The paper discusses whether this phenomenon is a real effect or whether it is a solver artefact and the study is supported by experimental evidence. The findings are preliminary, but suggest that it has a physical origin and that it may be aspect ratio-dependent.

• Journal of Industrial Technology
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• v.22 no.B
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• pp.21-26
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• 2002

The non-dimensional heat loss from a thermally asymmetric triangular fin is investigated as a function of a ratio of upper and lower surface Biot numbers (Bi2/Bi1), the non-dimensional fin length and tip surface Biot number using the two-dimensional separation of variables method. The effect of fin tip surface Biot number on the variation of the non-dimensional temperature along the sloped upper and lower surfaces for the thermally asymmetric condition is presented. The relationship between the non-dimensional fin length and the fin tip surface Biot number for equal amount of heat loss is also discussed as well as the relationship between upper surface Biot number and tip surface Biot number for equal amount of heat loss.