• Environmental and Resource Economics Review
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• v.17 no.4
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• pp.813-843
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• 2008

This paper investigates the presence of long-run and short-run price asymmetries in weekly gasoline prices from January 1997 to July 2008. In accordance with distribution channels, wholesale and retail stages are analyzed separately. An approach based on TAR and M-TAR cointegration tests, which entail matching asymmetric ECMs, is employed. For wholesale prices, asymmetries in the links with crude oil prices and exchange rates are found for both ECMs in the long-run and short-run. Exchange rates appear to play more significant role than crude oil prices in explaining the short-run price asymmetry. The rise in crude oil prices or exchange rates has statistically significant major impact on the increase of wholesale prices on the second week, not immediately as expected in the concept of 'rockets and feathers'. And asymmetrically, the fall does not have any statistically significant effect on the same period. The finding seems to be somewhat unusual. However, for retail prices, asymmetry m connection with wholesale prices is only revealed in the long-run. A symmetric price adjustment can be assumed in the short-run. Contrary to the long-run asymmetry found in the wholesale stage, in the retail stage, the speed of adjustment for negative deviations toward long-run equilibrium is faster than for positive ones, which is a phenomenon not favorable to consumers.

• Journal of Labour Economics
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• v.35 no.3
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• pp.29-50
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• 2012

This paper estimates the effect of minimum wages on new hiring of low wage workers from a time-series. The results indicate that minimum wages tend to reduce the new hiring of low wage workers, in particular, among women, less educated and older population. The strongly negative effect on new hiring suggests that the burden of reduced labor demand arising from higher minimum wages tend to fall mostly upon the unprotected low-wage job searchers due to the short-term rigidity of employment adjustment among the existing workers.

• 한국노년학
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• v.31 no.3
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• pp.553-571
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• 2011

The purpose of this research is to comparatively meta-analyze the total, short-term, and long-termeffectiveness of cases involving care of the elderly depression in the age range of 60 and over in the four countries, and to identify the relevant policy implications for developing depression care programmes for Korean older people. Ten studies conducted by RCT were found via AMED, EMBASE, Ovid Medline, PsycInfo. Use of Review Manager(5.5 version) shows that the interventions for caring depression were all effective: total effectiveness is OR=0.47(95% CI), short-termeffectiveness is OR=0.37(95% CI), and long-term effectiveness is OR=0.61(95% CI). This research provides three policy implications: Firstly, elements for increasing the long-term effectiveness of depression care interventions should be applied to all new programmes for caring elderly depression. Secondly, more focused depression interventions should be applied during the first half period of care programmes for elderly men, whilst the focus should be shifted to the last half period for elderly women. Finally, new interventions for caring depression that integrate both the medical and social support model of depression should be designed for elderly Koreans.

• Tuberculosis and Respiratory Diseases
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• v.45 no.3
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• pp.509-518
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• 1998

Background: Short-course chemotherapy for 6 months is well established for pulmonary tuberculosis. However, little is known about the efficacy of the short-course chemotherapy for tuberculous pleural effusion. Tuberculous pleural effusion itself may be self-limiting without any treatment, but about two thirds of the patients with tuberculous pleural effusion may subsequently develop pulmonary tuberculosis within 5 years. After completing treatment for tuberculous pleural effusion. prolonged follow-up is necessary for evaluating the efficacy of the treatment There is still no report on the efficacy of 6-month regimens for tuberculous pleural effusion in Korea, where the incidence of tuberculous disease and drug resistance is high. We studied the efficacy of 6 month short-course chemotherapy comparing with 9 month chemotherapy. Method : Retrospective study was done through medical record review in 238 patients with tuberculous pleural effusion who admitted to Asan Medical Center during May 1989-May 1993. The diagnosis of tuberculous pleural effusion was made by bacteriologic or histopathologic study. Results: Among 238 patients, 38 patients were dropped out during follow-up period. In 2 patients, second line drugs were prescribed according to known drug resistance results. And, in 23 patients, treatment longer than 9 months was done due to accompanying extrapulmonary tuberculosis or durg resistance. In 8 patients, treatment regimen was changed due to hepatotoxicity. Remaining 167 cases (70.2%) completed the treatment as scheduled ; 6 month chemotherapy in 88 cases and 9 month chemotherapy in 79 cases. In 60 patients (35.9%) with pleural effusion only in chest X-ray finding, sputum smear or culture for M.tuberculosis was positive in 6 cases (10.0%), and in 63 patients (37.7%) with radiologically inactive pulmonary tuberculosis, sputum smear or culture was positive in 18 cases (28.6%). In 44 patients (26.3%) with radiologically active pulmonary tuberculosis, the sputum smear or culture was positive in 24 cases (54.5%). In 6-month chemotherapy group (n=88), during mean 23 months (range; 1~61months) follow-up period, pulmonary tuberculosis developed in 1 case (1.4%). In 9-month chemotherapy group(n=79), during mean 23 months (range; 3~70months) follow-up period, pulmonary tuberculosis developed in 2 cases (2.5%). All the cases who developed pulmonary tuberculosis also showed active pulmonary tuberculosis on initial chest X-ray before treatment Conclusion: In patients with tuberculous pleural effusion, the incidence of pulmonary tuberculosis after 6 month chemotherapy showed no difference from that after 9 month chemotherapy. Thus, 6 month short-course chemotherapy seems to be an effective treatment for tuberculous pleural effusion.

• Journal of Satellite, Information and Communications
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• v.5 no.1
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• pp.43-47
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• 2010

In future mobile networks, hybrid/integrated satellite and terrestrial systems will play an important role. Most of the mobile communication systems are focused on the terrestrial systems, in this case, compatibilities between the satellite and terrestrial systems are very important for efficiency of the systems. Terrestrial systems of all the 4G mobile communication adopted the adaptive modulation and coding (AMC) schemes for efficient usage of resources, and the updating interval of resource allocation in an order of msec. However, because of the long round trip delay of satellite systems, we cannot employ the same AMC scheme specified for the terrestrial system, and thus it cannot effectively counteract to short term fadings. In the paper, we propose the method to apply AMC to mobile satellite systems. In addition, in order to effectively counteract to short term fadings, we present the simulation results of the AMC combined with an interleaver.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.919-923
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• 2012

본 연구에서는 K-water에서 자체 개발한 물리적 기반의 격자단위 강우-유출모형(K-DRUM ; K-water Distributed rainfall RUnoff Model)을 일 단위 장기유출 분석에 활용하기 위해서 유역의 증발산량 산정 및 융 적설 등을 모의할 수 있는 기능을 추가로 개발하였고, 재현성 분석을 위하여 남강댐 유역을 대상으로 장기유출모의를 수행하였다. 모의결과 단기 홍수사상의 경우 유출량에서 증발산 효과가 크지 않지만 연간 전체 유출량을 비교할 경우에는 상당한 차이가 발생하는 것을 확인할 수 있었다. 결과적으로 본 연구를 통해 개선된 K-DRUM 모형은 단기 홍수유출 뿐만 아니라 융 적설을 고려한 장기유출 분석에도 활용이 가능할 것으로 판단된다.

• KDI Journal of Economic Policy
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• v.31 no.2
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• pp.15-45
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• 2009

This paper estimates the term structure of interest rates with the setup of 3-factor no arbitrage model and investigates the trend of term premia and the effectiveness of changes in policy interest rates. The term premia are found to be high in a three-year medium term objective, which can be interpreted as reflecting the recognition of investors who expect a higher uncertainty in real activities for the coming three years than for a longer term. Then, in order to look into the effect of policy interest rates after the recent change of benchmark interest rate, this paper analyzes the effects of the changes in short-term interest rates of the financial market on the yield curve of the bond market at time of change. Empirical results show that the discrepancy between call rate, short-term rate in money market, and instantaneous short rate, short-term rate in the bond market, is found to be significantly widened, comparing to the periods before the change in benchmark interest rate. It is not easy to conclude clearly for now whether such a widening gap is caused by the lack of experiences with managing new benchmark interest rate or is just an exceptional case due to the recent turmoil in the global financial market. However, monetary policy needs to be operated in a manner that could reduce the gap to enhance its effectiveness.

• Journal of the Korean Geotechnical Society
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• v.23 no.8
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• pp.5-16
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• 2007

The stone column method is widely used in Europe as an alternative to conventional pile foundations. Several benefits of using the stone column method include sound performance, low cost, expediency of construction, and liquefaction resistance among others. Recently, geosynthetic-encased stone column approach has been developed to improve its load carrying capacity through increasing confinement effect. Although such a concept has been successfully applied in practice, fundamentals of the method have not been fully explored. This paper presents the results of an investigation on the load carrying capacity of geogrid-encased stone column using a series of 2D finite element analyses. A parametric study was then conducted for influencing factors such as effect of geogrid encasement, encasement length, geogrid strength, among others. The results of the analyses indicated improved short- and long-term load carrying capacity of the geogrid-encased stone column method has advantages over the conventional stone column method without encasing.

• Vending industry
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• v.11 no.2
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• pp.70-71
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• 2012

자판기를 단기적인 홍보 마케팅에 활용하는 사례들이 늘고 있다. 과거에는 사람이 자판기 안에 들어가 상품을 내주는 '인간자판기' 식의 활용이 붐을 이루었었다. 주로 미인이 자판기 안에 들어가 브랜드가 감성적으로 어필하는 효과를 안겨 주었다. 그러나 이런 홍보 마케팅은 여러 곳에서 되풀이함으로 인해 참신성이 떨어져 최근에는 시큰둥해졌다. '보다 기발하고 자극적인 방법이 무엇일까?' 다음으로 등장하게 된 게 자판기의 의외성을 부각시키는 컨셉이다. 고객이 예상했던 뻔한 내용상품이 아니라 놀랄만한 상품과 서비스, 재미를 제공한다. 일례로 코카콜라의 홍보 마케팅에서는 꽃다발을 내주기도 하고, 막걸리 업체 배다리의 전시회 홍보 마케팅에서는 투출구에서 사람 손이 나와 막걸리를 따라주기도 하고 선물도 건넨다. 최근 매일유업에서 '우유속에'라는 유제품 출시를 기념하여 펼쳐진 '해피 프레젠트 (Happy Present) 캠페인'도 이 범주에 속한다. 말 그대로 자판기가 다양한 선물을 하는 컨셉이다. 기존 유사 홍보마케팅과 차별성이 있다면 고객이 미션을 수행해야 선물이 주어지는 참여형 프로그램이라는 점이다. 의외성에 대한 기대와 재미를 결합한 절묘한 홍보 마케팅이다. 저렴한 비용에 효과는 만점인 자판기 홍보 마케팅의 장점을 여실히 느끼게 한다. '우유속에' 자판기 홍보 마케팅에는 어떠한 기발함이 숨어있을까?

• Proceedings of the Korean Society of Disaster Information Conference
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• 2022.10a
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• pp.75-76
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• 2022

본 연구는 기업과 그 기업이 속한 사회에서 사업을 영위하면서 자연재해의 발생이나 COVID-19와 같은 감염병의 유행으로 조직의 업무 중단이 발생하고 난 뒤 다시 사업을 재개하는 데에는 회복탄력성이 중요하다. 기업의 회복탄력성은 기업을 경영하는데 필요한 수많은 요소와 관련이 있다. 또한 기업과 연결된 많은 네트워크와 인프라에 의존하고 있다. 회복탄력성은 재난을 당한 뒤에 다시 사업을 영위하는 능력이라 할 수 있다. 재난에 대응하는 저항의 능력 보다는 기업의 핵심 기능이 단기간에 연속성을 확보하는데 그 의의가 있다고 하겠다. 이를 위하여 기업의 재난에 대한 '예방 활동', '대비 활동', '대응 활동'을 필수 요소로 삼고 있다. 그 외에 회복탄력성에 영향을 미치는 요인을 연구하기 위하여, 여유 자원, 협력관계, 전략적 유연성, 혁신성, 기술 변화 대응력이 조직역량에 미치는 영향력을 파악하고, 조직역량이 기업의 회복탄력성에 기여하는 정도를 파악하고자 하였다. (권재득, 2018). 회복탄력성의 미치는 추가요인인 외적 효과 분석에 대한 연구를 제안한다.