• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.17 no.2
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• pp.115-128
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• 2013

The optimal portfolio selection problem under inflation risk and subsistence constraints is considered. There are index bonds to invest in financial market and it helps to hedge the inflation risk. By applying the martingale method, the optimal consumption rate and the optimal portfolios are obtained explicitly. Furthermore, the quantitative effect of inflation risk and subsistence constraints on the optimal polices are also described.

• Journal of the Chungcheong Mathematical Society
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• v.34 no.2
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• pp.169-180
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• 2021

This paper investigates the time-inconsistent agent's optimal consumption and investment problem under inflation risk. The agents' discount factor is governed by hyperbolic discounting, which has a random time to change. We impose the inflation risk which plays a crucial role in long-term financial planning. We derive the semi-analytic solution to the problem of sophisticated agents when the time horizon is finite.

• Korean Management Science Review
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• v.30 no.1
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• pp.167-181
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• 2013

We investigate the dynamic asset allocation problem under inflation risk when the wealth of an investor is constrained with minimum requirements. To capture the investor's risk preference, the CRRA utility function is considered and he maximizes his expected utility at predetermined date of the refund by participation in the financial market. The financial market is supposed to consist of three kinds of financial instruments which are a risk free asset, a risky asset, and an index bond. The role of an index bond is managing inflation risk represented by price process. The optimal wealth and the optimal asset allocation are derived explicitly by using the method to get the European call option pricing formula. From the numerical results, it is confirmed that the investments on index bond is high when the investor's wealth level is low. However, as his wealth increases, the investments on index bond decreases and he invests on risky asset more. Furthermore, the minimum wealth constraint induces lower investment on risky asset but the effect of the constraints is reduced as the wealth level increases.

• Journal of the Chungcheong Mathematical Society
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• v.26 no.2
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• pp.343-349
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• 2013

The optimal portfolio selection problem under inflation risk is considered in this paper. There are three assets the economic agent can invest, which are a risk free bond, an index bond and a risky asset. By applying the martingale method, the optimal consumption rate and the optimal portfolios for each asset are obtained explicitly.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.595-605
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• 2021

The objectives of this research are to see if the phenomena of "demand following" and "supply leading" exist in the business cycle, as well as to look at how liquidity and output react to changes in credit risk, investment-saving gap, inflation, exchange rate, and growth rate of real national output. Employing quarterly data of Maluku and North Maluku (2008-2019), this study utilizes VAR/VECM for inferential analysis. This research found three important findings. First, liquidity and output growth influenced each other in the long run. Second, the determinants of output growth for Maluku are liquidity, investment-saving gap, and inflation, while the determinants of liquidity are output-growth, the gap of investment-saving, and inflation. Third, the determinants of output growth for North Maluku are liquidity, credit risk, investment-saving gap, inflation, exchange rate, and the national output-growth, while the determinants of liquidity are output-growth, credit risk, investment-saving gap, inflation, exchange rate, and national output-growth. The findings of this study supported the hypothesis of demand following and supply leading theory in the Maluku and North Maluku business cycles. This study concludes that economic development would improve if supported by liquidity adequacy through increased deposit growth.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.8-13
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• 2010

Many vehicles have significantly under-inflated tires, primarily because drivers infrequently check their vehicles' tire pressure. When a tire is used while significantly under-inflated, its sidewalls flex more and the tire temperature increases, increasing stress and the risk of failure. In this study we evaluated tire safety and economical efficiency at various inflation pressure. For tire safety we performed FMVSS indoor durability test, measurement of rolling tire temperature, braking performance at dry/wet road condition, and rolling resistance test for economical efficiency. Results show that low pressure decreases tire durability of both speed-increase condition and load-increase condition. Heat temperature of rolling tire increases as pressure decreases and significantly under-inflated tires cause increase of vehicle's stopping distance at wet road condition. Also Under-inflation increases the rolling resistance of a tire and, correspondingly, decreases vehicle's fuel economy.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.6
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• pp.108-117
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• 2003

Development of advanced restraint system challenges both restraint and automobile manufacturers to come up with proper airbag design to reduce occupant out-of-position related injury. The important component of the advanced restraint system is the multi stage inflator. The multi stage inflator can independently control two or more airbag inflation stages to maximize occupant protection. The objective of this research is to develop relationship between airbag inflation characteristics, the occupant positions and the airbag design variables. The tests are conducted using five kinds of inflators, two kinds of airbag cushion folding methods and two kinds of tear lines. In the case of inflator, the out-of-position tests are performed with a traditional inflator, a depowered inflator and a dual stage inflator. And the efficiency and injury mechanism are evaluated by analyzing the injury pulses and values. Using this relationship, airbag design guideline is established for airbag aggressivity thresholds and the risk of injury is identified according to occupant positions.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.1
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• pp.647-654
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• 2021

This study examines the non-performing loans of rural banks and macroeconomic factors in Indonesia, including inflation, exchange rates, and interest rates. Theoretically, the existence of erratic macroeconomic conditions can affect the level of non-performing credit risk in rural credit banks in Indonesia. The effect of macroeconomic conditions on non-performing loans has a different response for each economic sector. The main objective of this study is to determine the effect of macroeconomic factors (inflation, exchange rates, and interest rates) and bank-specific factors (credit) on the Non-Performing Loans (NPL) of Rural Banks in Indonesia for the period from January 2015 to December 2018. This study uses a Vector Error Correction Model (VECM) estimation to determine the effect of independent variables consisting of macroeconomic factors and bank-specific factors. Based on the estimation results of the Vector Error Correction Model, three variables that have a positive and significant effect on long-term non-performing loans are credit, inflation, and interest rates. Meanwhile, in the short term, there are only two variables that have a positive and significant effect on non-performing loans, namely, credit and interest rates. Inflation and exchange rate variables have a negative and insignificant effect on bad credit in the short term.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.195-201
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• 2021

This study aims to assess the impact of ownership structure of commercial banks on bank credit risk in Vietnam. The authors used the unbalanced table data of 28 commercial banks in the period from 2004 to 2020 with 439 observations. The ratio of loan loss provisioning to loans (CR) is selected as a dependent variable representing credit risk at commercial banks. The regression methods used include: least squares method (OLS), fixed-effect model (FEM), random-effect model (REM) and general least squares method (GLS). The results reveal that, with interaction variable between the ratio of equity to total assets and foreign ownership, the national GDP annual growth rate is negatively associated with credit risk. With the ratio of equity to total assets, the interaction variable between equity and state ownership, and bank size have a significant positive impact on credit risk. In addition, inflation has negligible impact on the credit risk of commercial banks in Vietnam over the research period. The findings of this study suggest that, if foreign-owned banks increase equity capital, there will be a stronger impact on reducing credit risk than other banks. On the other hand, when state-owned commercial banks in Vietnam increase equity, they will have higher credit risk.

• Archives of Plastic Surgery
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• v.47 no.6
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• pp.551-558
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• 2020

Background Giant congenital melanocytic nevus (GCMN) is a rare disease, for which complete surgical resection is recommended. However, the size of the lesions presents problems for the management of the condition. The most popular approach is to use a tissue expander; however, single-stage expansion in reconstructive surgery for GCMN cannot always address the entire defect. Few reports have compared tissue expansion techniques. The present study compared single and serial expansion to analyze the risk factors for complications and the surgical outcomes of the two techniques. Methods We retrospectively reviewed the medical charts of patients who underwent tissue expander reconstruction between March 2011 and July 2019. Serial expansion was indicated in cases of anatomically obvious defects after the first expansion, limited skin expansion with two more expander insertions, or capsular contracture after removal of the first expander. Results Fifty-five patients (88 cases) were analyzed, of whom 31 underwent serial expansion. The number of expanders inserted was higher in the serial-expansion group (P<0.001). The back and lower extremities were the most common locations for single and serial expansion, respectively (P =0.043). Multivariate analysis showed that sex (odds ratio [OR], 0.257; P=0.015), expander size (OR, 1.016; P=0.015), and inflation volume (OR, 0.987; P=0.015) were risk factors for complications. Conclusions Serial expansion is a good option for GCMN management. We demonstrated that large-sized expanders and large inflation volumes can lead to complications, and therefore require risk-reducing strategies. Nonetheless, serial expansion with proper management is appropriate for certain patients and can provide aesthetically satisfactory outcomes.