• 노동경제논집
• /
• 제39권2호
• /
• pp.35-51
• /
• 2016

2000~2008년 한국노동패널 자료를 이용한 미시 노동공급 탄력성 추정치는 0.23으로 나타났다. 분석대상 기간 중의 주5일 근무제 확대나 개별 가구의 소득 및 자산을 포함할 경우에도 추정치는 강건성을 보인다. 근로자들의 노동시장 참여 여부를 포함한 거시 노동공급 탄력성 추정치는 미시 노동공급 탄력성 추정치보다는 큰 값을 갖지만, 통상적인 유의수준에서 통계적으로 유의하지는 않았다.

• East Asian Economic Review
• /
• 제16권1호
• /
• pp.67-96
• /
• 2012

Previous literature has looked merely into the effect of trade facilitation on aggregate trade, or analyzed trade growth using the extensive and intensive margins. This paper blends these two lines of research for a detailed analysis of the impact of trade facilitation on trade by using highly disaggregated trade data and a more composite index for measuring trade facilitation, also taking into account the export sectors and income levels of countries. As a result, this paper finds that developing countries with higher trade facilitation levels export a wider range of products, especially primary goods. While trade facilitation levels do not have a statistically significant association with trade at the intensive margin in general, further analysis shows that the impact of advanced trade facilitation is the largest for lower middle-income countries in primary goods trade at the intensive margin, and the largest for upper middle-income countries in manufactured goods trade at the intensive margin. More importantly, our policy simulation results suggest that trade facilitation-related policy reforms enable developing countries to benefit from increased trade in manufactured goods at the extensive margin.

• KDI Journal of Economic Policy
• /
• 제31권2호
• /
• pp.195-234
• /
• 2009

본 연구에서는 Hummels and Klenow (2005)의 분석방식을 이용하여 1990년대 이후 우리나라의 대중국 수출에 있어서의 수출의 다양도 및 집약도의 상대적인 기여도를 고찰하고 있다. 본 연구에서 수출 다양도란 우리나라를 제외한 대중국 전체 수출국의 수출품목 대비 우리나라의 대중국 수출품목의 비중을 의미한다. 한편, 수출 집약도는 우리나라의 대중국 수출품목 기준으로 우리나라를 제외한 대중국 전체 수출국 대비 우리나라 수출의 비중으로 정의한다. 분석 결과에 의하면, 최근 1990년대 이후 우리나라의 대중국 수출 확대의 주요인은 수출 집약도의 증가였던 것으로 나타난다. 이러한 결과는 중장기적인 수출 호조세의 지속을 위해서는 수출 다양도보다는 수출 집약도가 더 중요한 요인이라는 $Besede{\check{s}}$ and Prusa(2007), Helpman, Melitz, and Rubinstein(2007) 등의 분석과 일치된 결과이다. 수출 다양도의 경우, 무역자유화 초기에 해당되는 1990년대 초반에는 빠르게 증가하나 이후에는 부품 및 자본재 등 일부 품목을 제외하고는 오히려 다소 하락하는 추세를 나타냈다. 한편, 부품과 자본재가 전반적으로 1차 산품, 소비재 등 여타 상품군들에 비해 수출의 지속성(survival)이 높은 것으로 나타난다. 1차 산품, 소비재 등의 경우 수출 개시 후 4년 이내에 전체의 약 75% 수준의 품목이 수출을 중단하는 것으로 분석된 반면, 부품과 자본재는 기술 수준의 구분 없이 1992~2007년 기간 중 지속적으로 수출이 이루어진 품목의 비중이 15% 수준에 이른다. 이러한 분석 결과는 국제분업구조의 진전이 수출의 지속성에 지대한 영향을 미칠 수 있음을 시사한다.

• 무역학회지
• /
• 제48권1호
• /
• pp.307-329
• /
• 2023

본 논문은 2021년 말까지 발효된 한국의 자유무역협정(FTA) 총 17건의 동태적 교역효과를 확인하기 위해 1996년부터 2021년까지 한국의 HS 10단위 상품 및 국가별 수입액 패널자료를 계량분석하였다. FTA의 협상개시, 협상타결 및 서명, 비준 및 발효 등의 무역정책 전환기(transition period)동안 동태적 교역효과를 분석한 결과, 협정의 발효 시점에 수입이 증가하는 효과는 뚜렷하며 특히, 새로운 교역상품의 등장에 따른 무역외연효과(extensive margin)가 중요한 역할을 하였다. 또한, 외연효과는 FTA의 발효에 따라 관세가 인하되기 이전부터 증가하는 추세를 보였다. 이는 최근 선행연구에서 확인된 잠재적 수출기업의 수출시장 조기진입현상을 뒷받침하는 중요한 결과이다. 특히, 이런 선행효과는 FTA 협상 개시 이후에 뚜렷하게 나타나, 정책 불확실성의 감소와 시장 조기진입현상의 관련성을 시사한다.

• Asian Journal of Innovation and Policy
• /
• 제11권1호
• /
• pp.69-86
• /
• 2022

This study examines performances and varieties of export of IP sensitive products across emerging countries, namely, India and China by utilizing 6-digit disaggregated product-level export data. Further, this study constructs trade margins - extensive and intensive margins to understand trade potential and different trade patterns, specifically, exporters' productivity, product diversification, and volume of trade during 2007-2016. This study finds India's performance is comparable with China at the extensive margin though the gap between India and China is very wide in terms of the total value of exports and the intensive margin. China majorly exports more expensive electronics and manufacturing-related products as opposed to relatively cheaper medicinal and synthetic products, the total value of exports from China to the rest of the world is much higher than that of India. This study suggests that India is exporting IP-sensitive products to lower-income countries sufficiently, but the IP-sensitive exports to higher-income countries are still lagging.

• Earthquakes and Structures
• /
• 제9권1호
• /
• pp.49-71
• /
• 2015

The present paper aims at evaluating damage and collapse behavior of low-rise buildings with unidirectional mass irregularities in plan (torsional buildings). In previous earthquake events, such buildings have been exposed to extensive damages and even total collapse in some cases. To investigate the performance and collapse behavior of such buildings from probabilistic points of view, three-dimensional three and six-story reinforced concrete models with unidirectional mass eccentricities ranging from 0% to 30% and designed with modern seismic design code provisions specific to intermediate ductility class were subjected to nonlinear static as well as extensive nonlinear incremental dynamic analysis (IDA) under a set of far-field real ground motions containing 21 two-component records. Performance of each model was then examined by means of calculating conventional seismic design parameters including the response reduction (R), structural overstrength (${\Omega}$) and structural ductility (${\mu}$) factors, calculation of probability distribution of maximum inter-story drift responses in two orthogonal directions and calculation collapse margin ratio (CMR) as an indicator of performance. Results demonstrate that substantial differences exist between the behavior of regular and irregular buildings in terms of lateral load capacity and collapse margin ratio. Also, results indicate that current seismic design parameters could be non-conservative for buildings with high levels of plan eccentricity and such structures do not meet the target "life safety" performance level based on safety margin against collapse. The adverse effects of plan irregularity on collapse safety of structures are more pronounced as the number of stories increases.

• Journal of Plant Biology
• /
• 제28권1호
• /
• pp.21-28
• /
• 1985

The bipinnate-compound leaf of Parkia clappertoniana has prominent, long petiole with a pulvinal base. The pulvinus has wood, periderm, lenticels and extensive cortical layer. Its vascular bundles are elongated with alternating rays. The vascular bundles of the petiole, rachis and veins are oval, with conspicuous bundle caps. Stomatal complex is predominantly paracytic with occasional occurrence of anomocytic stomata near the midrib. The oval stomata have conspicuous stomatal ledges. Trichomes are unicellular, acicular and restricted to the rachis, petiole and pinnule mid-ribs and margin. Ecological and taxonomic significance of features is discussed.

• Journal of Gastric Cancer
• /
• 제12권2호
• /
• pp.113-119
• /
• 2012

Purpose: The aim of this study is to compare the characteristics of tumor and prognosis, depending on the status of resection margin involvement, on the frozen section diagnosis in gastric cancer. Materials and Methods: This study was conducted retrospectively, in 83 margin-positive patients on the frozen section diagnosis, who underwent gastrectomy from July 1995 to September 2006. The control group was selected by matching the age, gender, TNM stage and status of adjuvant chemoradiotherapy, among those who had shown clear resection margins. The characteristics of tumor and patient survival are investigated, and they were analyzed between the two groups. Results: The tumor size was significantly larger in the study group than that of the control group (P=0.037). There was significant difference between the two groups in location of the tumors (P=0.003). Multivariate analysis indicated that only the location and Lauren's classification are independent factors, which affected the resection margin involvement. Median survival was $41.0{\pm}11.5$ months in the study group and $93.0{\pm}30.3$ months in the control group (P=0.049). In the survival analysis, it was investigated that TNM stage and the resection margin involvement of the frozen section diagnosis were the critical variables. Conclusions: When the tumor is located at the middle or the upper third, or the Lauren's indeterminate type, they are highly likely to show the resection margin involvement on the frozen section diagnosis, and it can, therefore, have negative effects on the prognosis. It is considered as good to perform more extensive resection as possible, during the initial resection.

• International Journal of Aeronautical and Space Sciences
• /
• 제12권1호
• /
• pp.78-83
• /
• 2011

Traditional autopilot design requires an accurate aerodynamic model and relies on a gain schedule to account for system nonlinearities. This paper presents the control architecture applied to a dynamic model inversion at a single flight condition with an on-line neural network (NN) in order to regulate errors caused by approximate inversion. This eliminates the need for an extensive design process and accurate aerodynamic data. The simulation results using a developed full nonlinear 6 degree of freedom model are presented. This paper also presents the stability evaluation for control systems to which NNs were applied. Although feedback can accommodate uncertainty to meet system performance specifications, uncertainty can also affect the stability of the control system. The importance of robustness has long been recognized and stability margins were developed to quantify it. However, the traditional stability margin techniques based on linear control theory can not be applied to control systems upon which a representative non-linear control method, such as NNs, has been applied. This paper presents an alternative stability margin technique for NNs applied to control systems based on the system responses to an inserted gain multiplier or time delay element.

• International Journal of Aeronautical and Space Sciences
• /
• 제18권1호
• /
• pp.91-98
• /
• 2017

Performance of a low speed axial compressor is enhanced through a proper configuration of blade row tip injection and casing treatment of groove type. Air injectors were mounted evenly spaced upstream of the blade row within the casing groove and were all aligned parallel to the compressor axis. The groove, which covers all the blade tip chord length, extends all-round the casing circumference. Method of investigation is based on solution of the unsteady form of the Navier-Stokes equations utilizing $k-{\omega}$ SST turbulence model. Extensive parametric studies have been carried out to explore effects of injectors' flow momentums and yaw angles on compressor performance, while being run at different throttle valve setting. Emphasis has been focused on situations near to stall condition. Unsteady numerical analyses for untreated casing and no-injection case for near stall condition provided to discover two well-known criteria for spike stall inception, i.e., blade leading edge spillage and trailing edge back-flow. Final results showed that with only 6 injectors mounted axially in the casing groove and at yaw angle of 15 degrees opposite the direction of the blade row rotation, with a total mass flow rate of only 0.5% of the compressor main flow, surprisingly, the stall margin improves by 15.5%.