• 산업공학
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• 제23권4호
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• pp.337-348
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• 2010

The Bass model is the most widely used model in research of new product diffusion because it presents a nice explanation on the diffusion process of new products. However, it has a limitation that its performance of fitness is lower as the available data become less and also, the diffusion curve is bell-shape and so, it can not represent the various diffusion patterns. Recently, a two-pieces Bass model is developed and applied to analyze diffusion of 10 products. The results are encouraging in terms of fitness. However, diffusion pattern is not dealt with in the paper. In this paper, analysis of diffusion pattern is in depth addressed in two-pieces Bass model. It is shown that the diffusion curves are divided into 3 types with respect to the peak adoption rate and each type is divided into 2 types further. Takeoff time of a diffusion process is analyzed by using the inflection point and regime-change time where it represents the point that imitation and innovation parameters change. Empirical studies for 68 products(28 domestic products and 40 USA products) are performed to analyze the diffusion pattern. Findings are that diffusion patterns of all products except 1 USA product show type I and regime-change time becomes shorter as the introduction time of the product is later in domestic products and regime-change time can be regarded as a takeoff time in 47% of total 68 products.

• 기술혁신학회지
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• 제7권2호
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• pp.351-372
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• 2004

This paper examines the change of innovation practices in the Korean industry which is entering into the 'post catching-up regime'. In catching-up regime, the technological loaming practices of Korean firms could be characterized as the assimilation and improvement of foreign technologies through crisis construction and time pressure. Crisis construction and time pressure were the important factors enhancing the intensity of technological teaming and shaping the way of doing imitative innovation. But the innovation patterns of firm are changing. The new ways of doing innovation are emerging in Korean mobile phone industry which is becoming a world leader： the emphasis on the importance of technological planning, the enhancement of collaborative networks among related firms, the toleration on the failure and the effort to acquire core technologies. Though Korean firms have not developed enough capabilities to create basic core technologies, they can develop their competitiveness through creative combination of technologies and are approaching the world frontier.

• 산업노동연구
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• 제24권1호
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• pp.1-28
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• 2018

이 논문은 노동자대투쟁 30주년을 맞아 민주노조운동의 현재를 거시적으로 평가하고 전망을 제시하고자 하였다. 민주노조운동은 1987년 노동체제의 공세기를 지나 1998년 이후 크게 약화되었다. 그 배경에는 종속 신자유주의 노동체제라는 노동체제의 구조변동이 자리하고 있었다. 노동운동은 과거의 전투적 노조주의를 그대로 유지함으로써 변화된 구조적 조건에 전략적으로 대응하지 못했던 것이다. 현재 민주노조운동은 전투적 경제주의, 정치경제주의, 불완전한 산별노조운동이라는 3중의 위기 상황에 봉착해있다. 그런데 2016년 갑자기 발생한 촛불혁명은 민주노조운동이 새로운 노동체제를 만들 수 있는 전망을 열어주었다. 촛불혁명은 일차적으로 정치변동이었지만 기존 노동체제의 문제점인 사회적 양극화와 비정규직 문제, 그리고 노동기본권문제를 해결하라는 요구를 담고 있었기 때문이다. 지금은 민주노조운동의 전면적 혁신이 긴요하다. 그리고 그것은 노동체제 전환이라는 전략적 목표 위에서 조직될 필요가 있다.

• 한국수산과학회지
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• 제41권6호
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• pp.493-504
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• 2008

In the seas around the Korean Peninsula, the seasonal cycle of zooplankton related to North Pacific regime shifts was investigated to understand the reaction of the ecosystem to climate change using long-term data on zooplankton biomass (1965-2000) and the abundance of four major zooplankton groups: copepods, amphipods, chaetognaths, and euphausiids (1978-2000). In general, the zooplankton biomass showed a large peak in spring and a small peak in autumnin Korean waters, but there was a slight difference in the peak time depending on the location and the period before and after the North Pacific regime shift. The zooplankton biomass showed conspicuous seasonal peaks in R-III (1990-2000) compared to R-I (1965-1976) and R-II (1977-1988), and the seasonal peak shifted from the autumn in R-II to the spring in R-III. The peak of copepods and euphausiids in abundance was from April to June, while chaetognaths peaked from August to October. We postulate that the time lag between the peaks for copepods and chaetognaths results from the predator-prey relationship. The regime shift in 1989 did not alter the seasonal cycle of the four major zooplankton groups, although it enhanced their production. The seasonal peaks of the four major zooplankton groups did not shift, while the seasonal peaks of the zooplankton biomass did shift. This was not only becausethe zooplankton biomass included other mesozooplankton groups but also because the abundance of the four major zooplankton groups increased significantly in spring.

• 동남아시아연구
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• 제28권3호
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• pp.213-261
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• 2018

2018년 5월 9일, 61년간 지속되던 말레이시아 집권연합인 국민전선(BN, Barisan Nasional)이 출범 2년차에 불과하던 야당연합인 희망연합(PH: Pakatan Harapan)에 의해 전격적으로 교체되었다. 총선에 출마했던 당사자들 조차 예측하지 못한 야당의 압승이었기에 1957년 독립 이후 최초로 이루어진 정권교체는 그야말로 순식간에 일어났다고 해도 과언이 아니다. 2018년 총선에서 BN의 패배는, 북한과 중국을 제외하고, 현존하는 현대정치체제 중에서 가장 오랫동안 지속되었던 패권적 집권세력의 몰락을 의미하였기에 세계적인 관심을 주목시켰다. 더욱이 이번 총선은 야권의 분열로 말미암아 1998년 개혁정국(reformasi) 이래 꾸준히 성사되었던 여야 간 일대일 대결이 무산되면서 모든 선거구에서 단일 여당 후보와 복수 야당 후보 간의 경선으로 치러졌기 때문에 그 결과는 더욱 놀랍고 충격적이었다. 도대체 어떻게 이런 결과가 일어날 수 있었는가? 특히 20년 가까이 지속된 야권의 공조에도 요원했던 정권교체가 야권의 분열에도 불구하고 이번 선거에서 달성될 수 있었던 동인은 무엇인가? 2018년 총선 결과는 말레이시아의 정치변동과 민주화 가능성에 어떠한 정치적 함의를 제공하는가? 앞으로 말레이시아 정국은 어떤 방향으로 전개될 것인가? 이에 대한 해답을 찾는 과정에서 1998년 개혁정국이 조성된 이후 치러진 일련의 총선들이 말레이시아 정가에서 "쓰나미(tsunami)"의 연속에 빗대어 비유되는 경향이 있음에 주목할 필요가 있다. 이런 쓰나미의 연속이라는 현상은, 비록 학계와 시민사회의 말레이시아 전문가들은 물론이고 정부여당과 야권 내부에서조차도 이번 총선에서의 정권교체 가능성을 예견한 사람은 거의 없었지만, 이번 총선에서의 정권교체가 갑자기 일어난 것이 아니라 지난 20년 간 지속된 말레이시아 유권자들의 선거를 통한 정치변동의 열망과 기대가 축적된 결과이라는 것을 의미한다. 이런 맥락에서, 이 연구는 2018년 총선 결과를 분석함에 있어서 독립 이후 최초로 정권교체가 달성될 수 있었던 특수한 상황적 요인과 함께, 1998년 개혁정국에 의해 촉발된 선거정치의 활성화가 결국 선거권위주의 체제의 붕괴로까지 귀결될 수 있었던 역학관계에 주목한다.

• 한국기후변화학회지
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• 제34권14호
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• pp.5621-5634
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• 2021

The life cycle of El Niño-Southern Oscillation (ENSO) typically follows a seasonal march, with onset in spring, developing during summer, maturing in boreal winter, and decaying over the following spring. This feature is referred to as ENSO phase locking. Recent studies have noted that seasonal modulation of the ENSO growth rate is essential for this process. This study investigates the fundamental effect of a seasonally varying growth rate on ENSO phase locking using a modified seasonally dependent recharge oscillator model. There are two phase locking regimes associated with the strength of the seasonal modulation of growth rate: 1) a weak regime in which only a single peak occurs and 2) a strong regime in which two types of events occur either with a single peak or with a double peak. Notably, there is a seasonal gap in the strong regime, during which the ENSO peak cannot occur because of large-scale ocean-atmosphere coupled processes. We also retrieve a simple analytical solution of the seasonal variance of ENSO, revealing that the variance is governed by the time integral of seasonally varying growth rate. Based on this formulation, we propose a seasonal energy index (SEI) that explains the seasonal gap and provides an intuitive explanation for ENSO phase locking, potentially applicable to global climate model ENSO diagnostics.

• Journal of Ecology and Environment
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• 제35권1호
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• pp.15-25
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• 2012

Time series of ocean climate indices and catch records were used to identify the alternation patterns of pelagic fish populations in relation to climate regime shifts. During 1910-2008, an orderly alternation of dominant pelagic fish groups was observed in the Tsushima Warm Current (TWC; Yellow Sea-East China Sea-East Sea/Japan Sea) and Kuroshio-Oyashio Current (KOC; Northwestern Pacific) regions. After the collapse of herring fishery in the late 1920s, the sardine (A group) dominated in the 1930s, 3 other species (C group; Pacific saury, jack mackerel, and anchovy) dominated in the 1950s-1960s, chub mackerel (B group) dominated in the 1970s, and then sardine (A group) dominated again during cool regime in the 1980s. As sardine biomass decreased in association with the climate regime shift that occurred in the late 1980s, catches of C group immediately increased after the regime shift and remained at high levels during warm regime in the 1990s. Alternations of dominant fish groups occurred 6 times between 1910 and 2008. The dominant period of the 7 species lasted for 10-20 years. The catch of Pacific sardine in the TWC and KOC regions showed a negative correlation with the catch of the other 5 species (Pacific herring, anchovy, jack mackerel, Pacific saury, and common squid), suggesting that the abundance of the 5 species is strongly affected by the abundance of Pacific sardine in relation to the climate regime shifts. The total catch level of the 7 species in the KOC region was generally higher than that in the TWC region before 1991 but was lower after 1992, suggesting that the fish populations in the Pacific side are shifted to the TWC region by zonal oscillation of the oceanic conditions in relation to the climate regime shift in the late 1980s.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.261-261
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• 2000

This paper analyzes the characteristics of pre-sliding friction of an X-Y table of CNC machining center at velocity reversal, and presents a simple and effective method of friction compensation based on this characteristics. At velocity reversal, a large position tracking error occurs because of the discontinuous change of friction. The relationship between the occurrence time of maximum position tracking error and the acceleration at zero velocity is analyzed by using the spring-like friction model. Furthermore, the experimental observation verifies this relation. From this, the state transition tine from pre-sliding regime into sliding regime can be predicted. Using the predicted transition time, the friction can be effectively compensated and table experimental results show its effectiveness.

• 환경정책연구
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• 제1권1호
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• pp.1-24
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• 2002

Due to the recent increase in greenhouse gases in atmosphere, world climate is rapidly changing and in turn, the earth ecosystem responds upon the climate changes. Comparing the ecosystem in the past, the present shapes of ecosystem is the result of the serious modification. Fishery resources in marine ecosystem, which usually occupy the upper trophic level, are also inevitable from such changes, because they always react to the natural environmental conditions. The northwestern Pacific is the most productive ocean in the world producing about 30% of world catch. From time to time, however, it has been notified that abundance, distribution and species composition of major fish species were altered by climate events. Furthermore, primary productivity of the ocean is not stable under the changing environments, so that carrying capacity of the ocean varies from one climate regime to another. Major climate events such as global warming, atmospheric circulation pattern, climate regime shift in the North Pacific, and El Nino event in the Pacific tropical waters were introduced in relation to fisheries aspects. The current status and future projection of fishery production was investigated, especially in the North Pacific including Korean waters. This new paradigm, ecosystem response to environmental variability, has become the main theme in marine ecology and fishery science, and the GLOBEC-type researches might provide a solution far cause-effect mechanism as well as prediction capability. Ecosystem management principles for multi-species should be adopted for better understanding and management of ecosystem.

• 한국기후변화학회지
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• 제7권1호
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• pp.49-57
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• 2016

In the present study, the time series of the number of days on which temperatures were not higher than $-5^{\circ}C$ in winter in Seoul was analyzed. The results showed a decreasing tendency until recently. Statistical change-point analysis was conducted to examine whether climate regime shifts existed in this time series. According to the results, the number of days on which temperatures were not higher than $-5^{\circ}C$ in winter in Seoul drastically decreased since 1988. Therefore, to find out the reason for the recent decrease in the number of days, differences between the means of large-scale environments in winder during 1988~2010 and those during 1974~1987 were analyzed. In all layers of the troposphere, anomalous anticyclones developed in regions around the Korean Peninsula and thus the Korean Peninsula was affected by westerlies or south-westerlies. This was associated with the recent a little further northward development of western North Pacific subtropical high. Therefore, environments good for warm and humid air to flow into the Korean Peninsula were formed. To examine whether relatively warm and humid air actually flowed into the Korean Peninsula recently, temperatures and specific humidity in all layers in the troposphere were analyzed and according to the results the Korean Peninsula showed warm and humid anomalies. In the analyses of sensible heat net flux and maximum temperatures at a height of 2 m that can be felt by humans, the East Asia Continent including the Korean Peninsula showed positive anomalies.