• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2008년도 추계학술대회 논문집
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• pp.543-544
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• 2008

• 대한토목학회논문집
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• 제9권1호
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• pp.41-52
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• 1989

ADI 방법, Hansen 방법, Heaps 방법, Richtmyer 방법, MacCormack 방법 등 5가지 유한차분방법을 사용하여 천수방정식에 대한 수치실험을 행하였다. 해석적 해가 존재하는 선형모형에 적용하여 안정성, CPU시간, 정확성 등을 검토하였고 비선형모형에 적용하여 순환현상을 모의하였다. 그 결과 ADI방법은 CPU시간이 가장 길고 유속에 대한 정확성이 다소 떨어진다는 결점이 있는 반면 순환현상을 가장 잘 모의한다는 것과 안정성에서 큰 장점이 있었다. 양해법 중에선 Richtmyer 방법이 비교적 우수한 방법으로 평가되었다. 한편 유효점성항은 천수방정식의 수치해석시 필수적이라는 결론도 얻었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.92-96
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• 1996

최근 유용한 신소재로많은 광심을 보이고 있는 오스템퍼처리 구상흑연 주철(Austempered Ductile Cast Iron 이하 ADI라 한다) 은 기지조직이 베이나이트와 잔류 오스테나이트로 구성되어있기 때문에 같은 화학 조성을 갖는 일반 구상 흑연 주철에 비하여 연성 및 연성의 감소가 없이 2배 정도의 강도를 증가 시킬수 있기 때문에 자동차, 선박 부품 및 각종 기계부품에 적용시키기 위한 많은 연구가 진행되고 있다. 본 연구에서는 서로 재질의 성분이 다른 고속도강 드릴인 소경드릴을 이용하여 ADI재료를 보통(비관통)이송 및 단계이송 절삭가공시 발생되는 공구의 마멸량과 표면조도와의 관계, 절삭력의 변화에 따른 공구마멸과 공구수명과의 관계를 실험적으로 규명하여 ADI재료 의 보통 및 단계이송절삭시 공구수명에 미치는 제반 절삭특성의 영향에 관해 고찰 하고자 한다.

• 한국환경보건학회지
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• 제38권6호
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• pp.550-560
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• 2012

Objectives: QSAR methodology was applied to explain two different sets of acceptable daily intake (ADI) data of 74 pesticides proposed by both the USEPA and WHO in terms of setting guidelines for food and drinking water. Methods: A subset of calculated descriptors was selected from Dragon$^{(R)}$ software. QSARs were then developed utilizing a statistical technique, genetic algorithm-multiple linear regression (GA-MLR). The differences in each specific model in the prediction of the ADI of the pesticides were discussed. Results: The stepwise multiple linear regression analysis resulted in a statistically significant QSAR model with five descriptors. Resultant QSAR models were robust, showing good utility across multiple classes of pesticide compounds. The applicability domain was also defined. The proposed models were robust and satisfactory. Conclusions: The QSAR model could be a feasible and effective tool for predicting ADI and for the comparison of logADIEPA to logADIWHO. The statistical results agree with the fact that USEPA focuses on more subtle endpoints than does WHO.

• 한국생산제조학회지
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• 제8권6호
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• pp.71-77
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• 1999

Monitoring of Cutting tool wear is a critical issue in automated machining system and has been extensively studied for many years. An austempered ductile iron(ADI) exhibits the excellent mechanical properties and the wear resistance. ADI has generally the poor machinability due to the characteristic. This paper presents the in-process detection of flank wear of cutting tools using the acoustic emission sensor and the digital oscilloscope. The amplitude level of AE signal(AErms) is mainly affected by cutting speed and it is proportional to cutting speed. There have been the relationship of direct proportion between the amplitude level of AE signals and the flank wear width of cutting tool. The flank wear with corresponding to the tool life is successfully detected with the monitor-ing system used in this study.

• Journal of Korea Trade
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• 제25권1호
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• pp.1-17
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• 2021

Purpose - The global trend of protectionism has expanded since the onset of US President Donald Trump's administration in 2017. This global phenomenon has led to a significant reduction in world trade volume and a negative impact on economic development in some countries where the external sector accounts for a large proportion of GDP. Although Korea is a country vulnerable to this deteriorating trade environment, few studies have examined the relationship between protectionism and its business cycles based on Korean data. Thus, this paper investigates the impact of protectionism on Korea's business cycle. Design/methodology - To identify future implications, we conduct a structural vector autoregression (VAR) analysis using monthly Korean data from 1994 to 2015. Macroeconomic variables in the model include the industrial production index, inflation rates, exports (or net exports), interest rates, and exchange rates. For the identification of the shock reflecting the expansion of protectionism, we use an antidumping investigation (ADI) data. Since ADIs are followed generally by the imposition of antidumping tariffs, they have no contemporaneous impact on tariffs and are also contemporaneously exogenous to other endogenous variables in the VAR model. We examine two kinds of ADI shocks i) shocks on Korean exports imposed by Korea's trading partners (ADI-imposed shocks) and ii) shocks on imports imposed by the Korean government (ADI-imposing shocks). Findings - We find that Korea's exports decline sharply due to ADI-imposed shocks; the lowest point at the third month after the initial shock; and do not recover until 24 months later. Simultaneously, the inflation rate decreases. Therefore, the ADI-imposed shock can be regarded as a negative shock on the demand curve where both production and price decrease. In contrast, the ADI-imposing shock generates a different response. The net exports decline, but the inflation rate increases. These can be seen as standard responses with respect to the negative shock on the supply curve. Originality/value - We shed light on the relationship between protectionism and Korea's economic fluctuations, which is rarely addressed in previous studies. We also consider the effects of both protective policy measures on imports to Korea imposed by the Korean government and on policy measures imposed by Korea's trading partner countries on its exports.

• 대한통합의학회지
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• 제7권1호
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• pp.19-26
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• 2019

Purpose : The aim of this study was to investigate the effects of the abdominal draw-in (ADI) exercise on the onset times of the gluteus maximus (GM) and erector spinae (ES) as well as the pelvic anterior tilt angle during prone hip extension (PHE). Methods : A total of 24 female adults were divided into two groups: those with normal abdominal muscles (n=12) and those with weak abdominal muscles (WAM; n=12). Before the intervention, the onset times of the GM and ES along with the pelvic angle during PHE were measured. Subsequently, the participants conducted the ADI exercise for 10 minutes. After conducting the ADI exercise, the onset times and the pelvic angle were re-measured. Results : In the pre-intervention comparison between the two groups, the WAM group showed faster ES onset times and higher pelvic angle than the normal group (p<0.05). In the WAM group, the ES onset times were significantly delayed after the ADI exercise (p<0.05). In both groups, the pelvic angle was significantly decreased after the ADI exercise (p<0.05). The decrease in the pelvic angle was significantly greater in the WAM group than in the normal group (p<0.05). The GM onset time was found to be not significant in all comparisons (p>0.05). Conclusion : Therefore, it can be concluded that after performing the ADI exercise, the pelvic anterior tilt during PHE is decreased in normal women and those with WAM, especially in the WAM group, suggesting that the ADI exercise can reduce the compensatory pelvic anterior tilt more effectively by delaying the ES onset times.

• 한국주조공학회지
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• 제15권6호
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• pp.527-532
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• 1995

• 한국전문물리치료학회지
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• 제26권2호
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• pp.8-15
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• 2019

Background: Improvement of the lumbo-pelvic stability can reduce the compensatory action of the erector spinae (ES) during prone hip extension (PHE). Furthermore, the application of abdominal drawing-in (ADI) maneuver increases the action of gluteus maximus (GM) and decreases the action of ES during PHE by improving the lumbo-pelvic stability. However, the post-ADI exercise effects on PHE, not the real-time application of ADI maneuver, has not been studied. Objects: This study is aimed at investigating the post-ADI exercise effects on the muscle activities of GM and ES during PHE. Methods: A total of 24 female adults participated in the study, and they were divided into two groups: Those with normal abdominal muscles ($n_1=12$) and those with weak abdominal muscles (WA) ($n_2=12$). Before the intervention, the subjects' GM and ES muscle activities during PHE were measured. Subsequently, the two groups were asked to perform the ADI exercise for 10 minutes. After the ADI exercise, the GM and ES activities were equally measured during PHE. Results: The comparison result of the ES muscle activities before intervention shows a significant difference between the two groups (p<.05); the WA group showed higher muscle activities than the normal group. For the within-group comparison, the muscle activities of the ES in the WA group significantly decreased after the ADI exercise (p<.05). For the GM muscle activity, no significant difference was observed in all comparisons (p>.05). For the changes in muscle activities before and after the ADI exercise, a significant difference exists between the two groups only for the changes in ES activities (p<.05); WA group exhibits higher changes than the normal group. By contrast, no significant difference exists between the two groups for the changes in GM activities (p>.05). Conclusion: After the ADI exercise, the compensatory action of ES in the female adults with WC is implied to decrease during PHE.

• 대한전자공학회논문지TC
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• 제39권10호
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• pp.38-45
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• 2002

본 논문에서는 기존의 Compact 2D FDTD(Finite-Difference Time-Domain)에 대한 고속 알고리즘으로써 시간간격 △t가 안정조건(Stability Condition)에 의해 제한받지 않는 Compact 2D ADI(Alternating Direction Implicit)-FDTD 차분식을 제안하였다. 또한 구현된 알고리즘의 정확성 및 효율성을 검증하기 위하여 내부가 공기로 채워져 있는 구형(Rectangular) 도파관과 차폐된 전송선로를 해석하였다. 본 논문의 결과는 기존의 Compact 2D FDTD의 결과 및 해석적인 해와 매우 잘 일치하며, 계산 소요시간도 기존의 Compact 2D FDTD에 비해 상당히 절약되었음을 확인하였다. 제안된 알고리즘은 도파관 구조의 분산 특성 연구에 있어 효율적인 고속화 기술로서 의미가 있다고 할 수 있다.