• Journal of Korea Trade
• /
• v.26 no.2
• /
• pp.21-44
• /
• 2022

Purpose - This study quantifies sources of trade balance dynamics over the business cycle in Korea. Specifically, we quantify the relative importance of domestic and foreign factors on trade balance dynamics using a small open economy real business cycle (SOE-RBC) model and provide policy implications for stabilization policies. Aggregate productivity and interest rate spreads are considered domestic factors affecting the trade balance. A world interest rate (the U.S. interest rate) is considered a foreign factor. Design/methodology - Following Neumeyer and Perri (2005), we build the SOE-RBC model with three types of shocks: aggregate productivity, interest rate spread, and world interest shocks. The model is estimated by the generalized method of moments (GMM) using relevant business cycle statistics. The estimated model is used for quantifying the relative importance of domestic and foreign factors on trade balance dynamics in Korea. Findings - Our main findings can be summarized as follows: 85.64% of the trade balance fluctuations in Korea are explained by domestic factors, the remaining 14.35% by foreign factors. Particularly, trade balance dynamics are mostly accounted for by the change in aggregate productivity shocks (85.58%). World interest rate shocks considerably explain trade balance (14.35%), whereas the role of interest rate spread shocks that represent domestic risks is limited (0.08%). Although aggregate productivity is key in explaining trade balance dynamics in Korea, interest rates still have an essential role. This is because aggregate productivity changes induce interest rate spread variations and, thus, the trade balance significantly. The results suggest that government policies mitigating fluctuations in aggregate productivity would be effective for stabilization policies in Korea by reducing the trade balance volatility. Originality/value - Existing studies on the emerging market business cycle examine mostly Latin American countries, and the main object of the studies is the volatility of consumption rather than trade balance dynamics. Conversely, our study examines Korea rather than Latin American countries. Additionally, we examine sources of trade balance dynamics, which are relatively more important in Korea, rather than those of the volatility of consumption. Hence, we estimate the model to explicitly match moments related to trade balance in the data.

• Journal of Korea Port Economic Association
• /
• v.38 no.2
• /
• pp.123-138
• /
• 2022

Korea has been huge investments in its port system, annually upgrading its infrastructure to turn the ports into Asian hub port. However, while Busan port is ranked fifth globally for container throughput, Other Korean ports are ranked much lower. This article applies Data Envelopment Analysis (DEA) and Malmquist Productivity Index (MPI) to evaluate selected major Korean seaports' operational efficiency and productivity from 2010 to 2018. It further integrates Principal Component Analysis (PCA) into DEA, with the PCA-DEA combined model strengthening the basic DEA results, as the discriminatory power weakens when the variable number exceeds the number of Decision Making Units(DMU). Meanwhile, MPI is applied to measure the seaports' productivity over the years. The analyses generate efficiency and productivity rankings for Korean seaports. The results show that except for Gwangyang and Ulsan port, none of the selected seaports is currently efficient enough in their operations. The study also indicates that technological progress has led to impactful changes in the productivity of Korean seaports.

• Economic Analysis
• /
• v.25 no.3
• /
• pp.1-29
• /
• 2019

This paper examines the impact of a dual labor market structure on labor productivity using unbalanced panel data from 29 OECD member countries between 1990 and 2015. By applying a variety of regression models on the panel data (e.g., a pooled regression, a fixed effects model and a GMM), we explore how changes in worker-type composition among temporary, permanent and self-employed workers contribute to productivity growth. While it appears that our results differ slightly, depending on the econometric models, overall an increase in the share of permanent workers leads to a relatively higher increase in productivity growth. On the other hand, it is also seen that the effects of the share of temporary workers on labor productivity are considerably lower than that of permanent and self-employed workers. To sum it up, our findings indicate that an increase in temporary workers could have an adverse effect on labor productivity.

• The Korean Journal of Ecology
• /
• v.19 no.1
• /
• pp.1-7
• /
• 1996

The net primary productivity and potential natural vegetation in the Korean peninsula in the 21st century were estimated by the Miami model and thermal climate, respectively, based on 148 meteorological data sets. In the 21st century, the distribution range of the net primary produtivity in the Korean peninsula was estimated as 1,050 g $DM{\cdot}m^{-2}{\cdot}yr^{-1}~2,050g\;DM\cdot m^-2\cdot yr^{-1}.\; These\; values\; increased\; by\; 200g\; DM\cdot m^{-2}\cdot yr^{-1}\;on\;northern\;part\;and\;400g\; DM\cdot m^{-2}\cdot yr^{-1}$ on southern part compared with that of the present century. The potential natural vegetation in the Korean peninsula in the 21st century will change into the followings:coniferous forest on Mt. Paektu area, deciduous broadleaf forest on northern part, and evergreen broadleaf forset on southern part.

• YAKHAK HOEJI
• /
• v.44 no.1
• /
• pp.60-65
• /
• 2000

The yeast extract, coconut water, safflower seed oil, arachidonic acid, linolenic acid, jasmonic acid and methyl jasmonate were added to Gamborg's B$_{5}$ medium. The changes on productivity of baccatin III were estimated every 30 minutes and the results were compared using the selected high yielding cell culture system of Taxus cuspidata. In most cases, the peaks of baccatin III productivity occured at 90~120 min after addition of elicitors. Among the compound elicitors, safflower seed oil showed the highest productivity of baccatin III. Also arachidonic acid and linolenic acid increased the baccatin III production.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.6
• /
• pp.1036-1040
• /
• 2007

Sodium butyrate (NaBu) has been used to enhance protein expression levels in mammalian cell culture. To determine the clonal variability of recombinant Chinese hamster ovary (rCHO) cells in response to NaBu addition regarding specific antibody productivity $(q_{Ab})$, three rCHO clones were subjected to different concentrations of NaBu. For all three clones, NaBu addition inhibited cell growth and decreased cell viability in a dose-dependent manner. On the other hand, the enhancing effect of NaBu on $q_{Ab}$ varied significantly among the clones. NaBu addition enhanced the antibody production of only one clone. RT-PCR analysis revealed that the changes in $q_{Ab}$ correlated linearly with those of the mRNA transcription level. Thus, it was concluded that the different enhancing effects of NaBu on protein expression in rCHO cell clones resulted from their different mRNA transcription levels.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.5 no.6
• /
• pp.69-78
• /
• 1982

Traditional CVP (Cost-Volume-Profit) analysis employs linear cost and revenue functions within some specified time period and range of operations. Therefore CVP analysis is assumption of constant labor productivity. The use of linear cost functions implicity assumes, among other things, that firm's labor force is either a homogenous group or a collection homogenous subgroups in a constant mix, and that total production changes in a linear fashion through appropriate increase or decrease of seemingly interchangeable labor unit. But productivity rates in many firms are known to change with additional manufacturing experience in employee skill. Learning curve is intended to subsume the effects of all these resources of productivity. This learning phenomenon is quantifiable in the form of a learning curve, or manufacturing progress function. The purpose d this study is to show how alternative assumptions regarding a firm's labor force may be utilize by integrating conventional CVP analysis with learning curve theory, Explicit consideration of the effect of learning should substantially enrich CVP analysis and improve its use as a tool for planning and control of industry.

• Journal of the Korea Safety Management & Science
• /
• v.9 no.3
• /
• pp.135-142
• /
• 2007

The authors used association rules and patterns in sequential of data mining in order to raise the efficiency of engineering changes. The association rule can reduce the number of engineering changes since it can estimate the parts to be changed. The patterns in sequential can perform engineering changes effectively by estimating the parts to be changed from sequence estimation. According to this result, unnecessary engineering changes are eliminated and the number of engineering changes decrease. This method can be used for improving design quality and productivity in company managing engineering changes and related information.

• Journal of Navigation and Port Research
• /
• v.44 no.4
• /
• pp.338-346
• /
• 2020

In this study, we first measured the Malmquist productivity index by DEA among the Korean ocean carriers. Second, it was intended to present measures to improve productivity by identifying the influence and discriminating power between productivity and the major financial ratios (profitability, financial stability, liquidity, efficiency and value-added productivity). Compared to 2017, there are 11 more shipping carriers with decline in productivity (MPI) than those with an increase in 2018. The increase in productivity is attributed to an increase in the Technology Change Index (TCI) affected by the external environment. There is strong significant correlation between the productivity (MPI) and the management efficiency (CRS). Additionally, the TECI (TECHI) index of the technological efficiency changes from internal factors of the shipping carrier is significantly higher than that of the efficient shipping carrier. This is because of the differences in scale efficiency. The ratio of charter cost/sales is also lower than that of the carriers with high productivity (0.17) and with low productivity (0.21). With 7% of the shipping carrier with MPI>1, only 1% of MPI <1 is found to have a significant impact on its productivity.

• Korea Journal of Hospital Management
• /
• v.10 no.4
• /
• pp.51-74
• /
• 2005

This paper presents an analysis of the current status of domestic hospital industry which went trough the time of new hospitals operated by chaebols from 1994 to 2003 and the dramatic changes of medical service environment such as IMF relief loan in 1997 and the separation of prescription and dispensing (SPD) in 2000. For the sake of righteous policy-making in the future, this paper presents a productivity analysis of the management and administration of 38 tertiary hospitals nationwide in the past 10 years. The analysis is based on the Malmquist index approach using linear programming. d prepare a productivity index that measures not merely efficiency but the technological evolution and adjustment to changing environments.