• 한국항만경제학회지
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• 제27권1호
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• pp.235-245
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• 2011

본 논문은 조선산업의 경기가 환율 및 환율 변동성에 유의미한 영향을 미치는 것을 보이고 있다. 조선업 경기중에서 수주량과 건조량이 환율 및 환율 변동성에 선제적이 장기적인 영향을 미치는 것으로 나타났다. 이것은 조선업의 경기가 환율 및 환율 변동성을 파악하는 데 중요한 요인임을 시사한다. 이것은 선물환 매도와 같은 조선산업의 환헤지가 영향을 미치는 것으로 짐작된다. 본 논문 결과는 정책당국이 외환시장 안정을 위해 조선업 경기에 대한 모니터링이 필요함을 정책적 시사점을 제시하고 있다.

• International Journal of Internet, Broadcasting and Communication
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• 제12권3호
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• pp.125-130
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• 2020

At the end of 1997, the volatility of the exchange rate intensified as the nation's exchange rate system was converted into a free-floating exchange rate system. As a result, managing the exchange rate is becoming a very important task, and the need for forecasting the exchange rate is growing. The exchange rate prediction model using the existing exchange rate prediction method, statistical technique, cannot find a nonlinear pattern of the time series variable, and it is difficult to analyze the time series with the variability cluster phenomenon. And as the number of variables to be analyzed increases, the number of parameters to be estimated increases, and it is not easy to interpret the meaning of the estimated coefficients. Accordingly, the exchange rate prediction model using artificial neural network, rather than statistical technique, is presented. Using DNN, which is the basis of deep learning among artificial neural networks, and LSTM, a recurrent neural network model, the number of hidden layers, neurons, and activation function changes of each model found the optimal exchange rate prediction model. The study found that although there were model differences, LSTM models performed better than DNN models and performed best when the activation function was Tanh.

• 한국물환경학회지
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• 제25권5호
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• pp.750-757
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• 2009

The ammonium ion exchange characteristics of natural zeolite were investigated to remove ${NH_4}^+-N$. The effect of water temperature, particle size and competitive cation on the exchange capacity was examined. Ammonium ion exchange capacity tended to decrease when the temperature increased from $25^{\circ}C$ to $40^{\circ}C$. Exchange capacity was increased according to the particle size of natural zeolite comes to be small. Batch isotherm experiments were conducted for measuring ammonium ion exchange capacity. The ion exchange capacity was well described either by the Langmuir isotherm model or by the Freundlich isotherm model. The ammonium ion exchange capacity ($q_m$) of zeolite carrier can be calculated $11.744mg-{NH_4}^+/g$-carrier. The ion exchange capacity of manufactured zeolite carrier was showed a similar tendency as ion exchange capacity of powder-sized natural zeolite. Therefore, zeolite carrier can be used for increasing of nitrogen removal efficiency in the wastewater treatment plants.

• Journal of Advanced Marine Engineering and Technology
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• 제24권3호
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• pp.79-87
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• 2000

This paper describes experimental investigations of helium-air exchange flow through openings with vertical partitions. Such exchange flows may occur following rupture accident of stand pipe in high temperature gas cooled reactor. Exchange flow rates are investigated experimentally by using partitioned opening and opening with extended partition to assess fluids interference of the exchange flow at the stand pipe rupture accident. A tests vessel with the two types of opening on top of test cylinder is used in the experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. Amplitude and progress of interference fringes of the flows are observed and used as a support in comparison with the exchange flow rates. Flow passages of upward flow of the helium and downward flow of the air for both two types of the opening are separated by inserted partition within the opening, but in the case of partitioned opening, unseparated flow is formed at the opening entrance and the two flows interface. The exchange flow rate for the partitioned opening is not greater than that of the opening with extended partition because of the fluids interference at the entrance of opening. Finally, the fluids interference at the opening entrance is found to be one of important factors on the helium-air exchange flow rate.

• Journal of Advanced Marine Engineering and Technology
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• 제21권4호
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• pp.372-380
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• 1997

This paper describes experimental investigations of helium-air exchange flows through parti¬tioned opening and two-opening. Such exchange flows may occur following rupture accident of stand pipe in high temperature gas cooled reactor. A test vessel with the two types of small open¬ing on top of test cylinder is used for experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. In the case of exchange flow through the partitioned opening, flow passages of upward flow of the helium and downward flow of the air within the opening are separated by vertical partition, and the two flows interact out of entrance and exit of the opening. Therefore, an experiment of the exchange flow through two-opening is made to investigate effect of the fluids interaction of the partitioned opening sys¬tem. As a result of comparison of the exchange flow rates between the two types of the opening system, it is found that the exchange flow rate of the two-opening system is larger than that of the partitioned opening system due to absence of the effect of fluids interaction. Finally, the fluids interaction between the upward and downward flows through the partitioned opening is found to be an important factor on the helium-air exchange flow.

• Nuclear Engineering and Technology
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• 제40권6호
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• pp.489-496
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• 2008

Ferrocyanide-anion exchange resin was prepared and the prepared ion exchange resins were tested on the ability to uptake $Cs^+$ ion. The prepared ion exchange resins were resin-KCoFC, resin-KNiFC, and resin-KCuFC. The three tested ion exchange resins showed ion exchange selectivity on the $Cs^+$ ion of the surrogate soil decontamination solution, and resin-KCoFC showed the best $Cs^+$ ion uptake capability among the tested ion exchange resins. The ion exchange behaviors were explained well by the modified Dubinin-Polanyi equation. A regeneration feasibility study of the spent ion exchange resins was also performed by the successive application of hydrogen peroxide and hydrazine. The desorption of the $Cs^+$ ion from the ion exchange resin satisfied the electroneutrality condition in the oxidation step; the desorption of the $Fe^{2+}$ ion in the reduction step could also be reduced by adding the $K^+$ ion.

• The Journal of Asian Finance, Economics and Business
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• 제7권10호
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• pp.543-553
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• 2020

This paper examines the effect of COVID-19 pandemic on the Philippine stock exchange, peso-dollar rate and retail price of diesel using robust least squares regression and vector autoregression (VAR). The robust least squares regression using MM-estimation method concluded that COVID-19 daily infection has negative and statistically significant effect on the Philippine stock exchange index, peso-dollar exchange rate and retail pump price of diesel. This is consistent with the results of correlation diagnostics. As for the VAR model, the lag values of the independent variable disclose significance in explaining the Philippine stock exchange index, peso-dollar exchange rate and retail pump price of diesel. Moreover, in the short run, the impulse response function confirmed relative effect of COVID-19 daily infections and the variance decomposition divulge that COVID-19 daily infections have accounted for only minor portion in explaining fluctuations of the Philippine stock exchange index, peso-dollar exchange and retail pump price of diesel. In the long term, the influence levels off. The Granger causality test suggests that COVID-19 daily infections cause changes in the Philippine stock exchange index and peso-dollar exchange rate in the short run. However, COVID-19 infection has no causal link with retail pump price of diesel.

• The Journal of Asian Finance, Economics and Business
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• 제9권7호
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• pp.27-39
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• 2022

The exchange rate is an important macroeconomic variable that influences internal and external balances. Nepal follows a dual exchange rate such that the Nepali rupee (NPR) is pegged with the Indian rupee (INR) but floats with the United States dollar (USD) and all other currencies. There have been very few studies on the exchange rate of Nepal, of which the majority focus on the bivariate relationship between exchange rate and another variable. However, this paper analyses the multivariate relationship between the USD-NPR exchange rate and major macroeconomic variables. Determinants of Nepal's exchange rate have been derived with multiple regression using the ordinary least square (OLS) approach. Since the explanatory variables could not significantly capture the movement of the dependent variable, a long-run relationship between Nepal and India's exchange rate has been analyzed using Engle-Granger cointegration to establish a relationship as suggested by a graphical representation. This explains that Nepal's exchange rate long run is determined by India's exchange rate than its own fundamentals. In addition, the macro-linkages of Nepal's macroeconomic variables have been analyzed using Standard Vector Autoregressive models followed by impulse response analysis which is useful for policy decisions. Some policy implications indicating the sustainability of Nepal's pegged regime have been drawn based on the empirical analysis.

• 대한영양사협회학술지
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• 제10권2호
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• pp.129-142
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• 2004

The food exchanges are frequently used to nutrition education and counseling for diabetes, weight control, hyperlipidema and etc. But it is difficult to find out food exchange lists with food exchange groups in the food composition table. This study was conducted to select e-food exchange of commonly used foods(456 foods) and improve search system based on internet. Also, the e-food exchange database was developed as having the proximate composition, mineral and vitamin content such as energy, moisture, protein, fat, carbohydrate, ash, calcium, phosphorus, iron, sodium, potassium, retinol equivalent, retinol, a-carotene, thiamin, riboflavin, niacin, ascorbic acid, refuse per 100g of each food. The e-food exchange database developed is basically based on the 6th food composition table(2001) of the National Rural Living Science Institution in Rural Development Administration, Korea. The 456 commonly used foods or 2,262, all foods can be searched easily in a new system. A specific food of e-food exchange can be searched by a given set of food groups or food name and can give information about food one exchange lists, weight and nutrient value per 100g of each food user-friendly on internet. It can be used to make a nutritionally balanced meal plan, nutrition education and counseling.

• 한국콘텐츠학회논문지
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• 제21권12호
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• pp.448-462
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• 2021

온라인 커뮤니티에서 교환구조가 커뮤니티 결속력에 미치는 영향에 관한 연구는 매우 드물다. 더욱이 이 연구들은 서로 상충된 연구결과를 보고하고 있다. 본 연구는 이러한 연구결과를 재조명하기 위해 사회적 교환이론에 근거하여 커뮤니티 내 교환구조를 직접적 및 일반적 교환구조로 분류하고, 일반적 교환구조의 결정요인으로 지식의 분산도를 포함하였다. 그리고 상충된 연구결과를 설명하기 위해 교환혜택을 조절변수로 도입하였다. 본 연구는 네이버에서 활동하는 380개의 온라인 커뮤니티에서 데이터를 수집하여 분석하였다. 그 결과 지식의 분산도는 일반적 교환구조를 촉진하는 것으로 나타났다. 그리고 직접적, 일반적 교환구조 모두 커뮤니티 결속력에 긍정적 영향을 미치나, 이 관계는 교환혜택의 수준에 따라 조절되는 것으로 나타났다. 즉, 교환혜택이 높은 그룹에서는 일반적 교환구조가 직접적 교환구조보다 커뮤니티 결속력에 미치는 영향이 더 큰 반면, 교환혜택이 낮은 그룹에서는 두 교환구조의 영향력 사이에 통계적으로 유의미한 차이가 없는 것으로 나타났다.