• Title/Summary/Keyword: intensive observations

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Chemical Imprints of the Upwelled Waters off the Coast of the Southern East Sea of Korea

  • Lee, Tong-Sup;Kim, Il-Nam
    • Journal of the korean society of oceanography
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    • v.38 no.3
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    • pp.101-110
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    • 2003
  • We made intensive observations on the coastal upwelling off the coast of the southern East Sea from June to August in 2001. The upwelling exhibited a weekly waxing and waning. The coastal upwelling of the year 2001 was characterized by abrupt outbreaks and the small local scale. Upwelling occurred more frequently off the coast of Ulsan and Gampo as reported by the earlier observers. The spread of freshly upwelled colder water was varied by each upwelling event. Generally cold waters were carried away northeastward off Pohang province. The upwelled cold waters were saltier than the resident surface waters. The pH and salinity-normalized alkalinity support the idea that the upwelled waters originate from the interior of the East Sea. The extraordinarily high concentration of dissolved oxygen suggests that the upwelled waters are closely connected to the southward flowing North Korea Cold Current. Although a lower primary productivity was reported for the upwelling region, underway surface fluorescence measurement revealed that the recently upwelled waters supported up to an order of magnitude higher algal biomass than the ambient waters. Because thermohaline circulation of the East Sea is so vigorous, with an estimated time scale of less than one hundred years, that the coastal upwelling should be considered not as an anomaly but as a regular component of a circulatory system. A quantitative understanding of upwelling seems to be a key to elucidate material cycling and the associated biological production in the East Sea.

OBSERVATIONS OF TERRESTRIAL NIGHTGLOW (MEINEL BANDS) AT KING SEJONG STATION, ANTARCTICA

  • Won, Young-In;Cho, Young-Min;Lee, Bang-Yong;Kim, Jhoon;Chung, Jong-Kyun;Kim, Yong-Ha
    • Journal of Astronomy and Space Sciences
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    • v.16 no.2
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    • pp.149-158
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    • 1999
  • A Fourier Transform Spectrometer was used to study upper mesospheric thermodynamic by observing the hydroxyl(OH) emission. Rocket-born and satellited-born photometers place the peak emission near 87 km. The instrument was installed in February 1999 at King Sejong station ($62.22^{circ}S,301.25^{circ}E$), Antarctica and has been in routine operation since then. An intensive operational effort has resulted in a substantial data between April and June, 1999. A harmonic analysis was carried out to examine information on the tidal characteristics. The measured amplitudes of the 12-hour oscillation are in the range of 2.4-3.7 K, which are in resonable agreement with theoretical model outputs. The harmonic analysis also revealed 8-hour oscillation which is not expected from the traditional theoretical studies. In addition, the observed 8-hour oscillations are apparent and sometimes dominate the temperature variation in the upper mesosphere.

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Variability study of AGN in NGC 4395

  • Cho, Hojin;Woo, Jong-Hak;Son, Donghoon;Le, Huynh Anh;Bae, Hyun-Jin;Shin, Jaejin;Park, Songyoun;Cho, Wanjin;Hodges-Kluck, Edmund;Gallo, Ellena;Kim, Minjin;Park, Daeseong;Sung, Hyun-il;Kim, Taewoo;Kang, Wonseok
    • The Bulletin of The Korean Astronomical Society
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    • v.42 no.2
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    • pp.77.1-77.1
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    • 2017
  • We present the preliminary results from our intensive monitoring campaign for measuring continuum and line variability of a low-mass Seyfert galaxy, NGC 4395, which host a smallest known AGN black hole in the reverberation mapping studies. We performed consecutive photometric observations during 5 nights in April 2017. Various telescopes in the world, including BOAO 1.8-m, NYSC 1-m, MDM 2.4-m, 1.3-m, etc, were dedicated for this campaign. Preliminary results show that the tentative time lag can be determined, which is approximately order of 1-2 hours.

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Estimation of Sculptured Surface NC Machining Time (자유곡면 NC 절삭가공시간 예측)

  • 허은영;김보현;김동원
    • Korean Journal of Computational Design and Engineering
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    • v.8 no.4
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    • pp.254-261
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    • 2003
  • In mold and die shops, NC machining process mainly affects the quality of the machined surface and the manufacturing time of molds and dies. The estimation of NC machining time is a prerequisite to measure the machining productivity and to generate a process schedule, which generally includes the process sequence and the completion time of each process. It is required to take into account dynamic characteristics in the estimation, such as the ac/deceleration of NC machine controllers. Intensive observations at start and end points of NC blocks show that a minimum feedrate, a key variable in a machining time model, has a close relation to a block distance, an angle between blocks, and a command feedrate. Thus, this study addresses regression models for the minimum feedrate estimation on short and long NC blocks considering these parameters. Furthermore, machining time estimation models by the four types of feedrate behaviors are suggested based on the estimated minimum feedrate. To show the validity of the proposed machining time model, the study compares the estimated with the actual machining time in the sculptured surface machining of several mold dies.

Sensible heat flux estimated by gradient method at Goheung bay wetland (고흥만 습지에서 경도법으로 산출한 현열플럭스)

  • Kim, Dong-Su;Kwon, Byung-Hyuk;Kim, Il Kyu;Kang, Dong Hwan;Kim, Kwang-Ho;Kim, Geun-Hoi;Park, Jun-Sang
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.2
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    • pp.156-167
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    • 2008
  • Meorological data have been collected to monitor the wetland area in Goheung bay since 2003 and four intensive observations were conducted to study effects of the atmospheric turbulence on the energy budget and the ecological changes. We improved an algorithm to estimate the sensible heat flux with routine data. The sensible heat flux estimated by gradient method was in good agreement with that measured by precision instruments such as surface layer scintillometer and ultrasonic anemometer. Diurnal variations of sensible heat flux showed analogous tendency to those of temperature gradient. When the vertical wind shear of horizontal wind components was weak, even though temperature gradient was strong, the gradient method underestimated the sensible heat flux. A compensation for the cloud will make this gradient method be a helpful tool to monitor the ecosystem without expensive instruments except for weak wind shear and temperature gradient.

Experiences of Admission for Critically Ill Patients in ICU (중환자실 환자의 입원 경험)

  • Yang, Jin-Hyang
    • Korean Journal of Adult Nursing
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    • v.20 no.1
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    • pp.149-162
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    • 2008
  • Purpose: The purpose of this study was to understand the meanings and nature of ICU admission experienced among patients with critical illness. The present study adopted a hermeneutic phenomenological method which was developed by van Manen. Methods: The participants for this study were 6 men and 3 women, who were over the age of 20 with ICU admission period more than 3 days. Data were collected by using in-depth interviews and observations from March, 2007 to September, 2007. The contents of the interviews were tape-recorded with the consent of the subject. Results: The essential themes that fit into the context of the 4 existential grounds of body, time, space and other people were as follows: a body that cannot react the way it wants, a wave of fear and insecurity everywhere, a struggle to survive, coming out from death's door, loss of time path, a long and continued waiting until escaping, more of machinery room than a patient's room, existence of life and death, an abyss of suffering seen thru another patient, taken care of by a doctor, trust and distrust, family, the ultimate safe zone. Conclusion: Critically ill patients in ICU experienced feelings of discomfort, unsafety, and insecurity. The result of this study can give nurses some insight into these experiences and help promote empathetic care.

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Causality join query processing for data stream by spatio-temporal sliding window (시공간 슬라이딩윈도우기법을 이용한 데이터스트림의 인과관계 결합질의처리방법)

  • Kwon, O-Je;Li, Ki-Joune
    • Spatial Information Research
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    • v.16 no.2
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    • pp.219-236
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    • 2008
  • Data stream collected from sensors contain a large amount of useful information including causality relationships. The causality join query for data stream is to retrieve a set of pairs (cause, effect) from streams of data. A part of causality pairs may however be lost from the query result, due to the delay from sensors to a data stream management system, and the limited size of sliding windows. In this paper, we first investigate spatial, temporal, and spatio-temporal aspects of the causality join query for data stream. Second, we propose several strategies for sliding window management based on these observations. The accuracy of the proposed strategies is studied by intensive experiments, and the result shows that we improve the accuracy of causality join query in data stream from simple FIFO strategy.

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THE PREDICTION OF SOLAR ACTIVITY FOR SOLAR MAXIMUM (태양활동극대기를 대비한 태양활동예보)

  • LEE JINNY;JANG SE JIN;KIM YEON HAN;KIM KAP-SUNG
    • Publications of The Korean Astronomical Society
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    • v.14 no.2
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    • pp.103-112
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    • 1999
  • We have investigated the solar activity variation with period shorter than 1000 days, through Fourier transformation of solar cycle 21 and 22 data. And real time predictions of the flare maximum intensity have been made by multilinear regression method to allow the use of multivariate vectors of sunspot groups or active region characteristics. In addition, we have examined the evolution of magnetic field and current density in active regions at times before and after flare occurrence, to check short term variability of solar activity. According to our results of calculation, solar activity changes with periods of 27.1, 28.0, 52.1, 156.3, 333.3 days for solar cycle 21 and of 26.5, 27.1, 28.9, 54.1, 154, 176.7, 384.6 days for solar cycle 22. Periodic components of about 27, 28, 53, 155 days are found simultaneously at all of two solar cycles. Finally, from our intensive analysis of solar activity data for three different terms of $1977\~1982,\; 1975\~1998,\;and\;1978\~1982$, we find out that our predictions coincide with observations at hit rate of $76\%,\;63\%$, 59 respectively.

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Corporate Governance, Family Ownership, and Earnings Management: A Case Study in Indonesia

  • WIDAGDO, Ari Kuncara;RAHMAWATI, Rahmawati;MURNI, Sri;RATNANINGRUM, Ratnaningrum
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.5
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    • pp.679-688
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    • 2021
  • This study aims to verify family ownership's effect on earnings management by using corporate governance as the moderation variable. This study uses data panel regression with the period of 2011-2017. Corporate governance consisted of three dimensions, namely the board of commissioners, share ownership and transparency, and disclosure and auditing. Discretionary accruals measure earnings management with a model that controls company performance. Samples are manufacturing companies listed on Indonesia Stock Exchange. Observations were conducted on 198 firms throughout the year. The results indicated that corporate governance significantly affected earnings management. However, it declined the significance of family ownership toward earnings management. Hence, corporate governance can reduce earnings management. Furthermore, of the three components of corporate governance: the board of commissioners, shareholding, and transparency, the term shareholding precisely encouraged managers to conduct earnings management. Besides, the three core bodies of corporate governance lowered the significance of shareholding toward earnings management. This study's findings suggest that in family firms in Indonesia, earnings management is becoming more intensive than in non-family firms. Additional tests show that there is an entrenchment effect on family firms in Indonesia. Furthermore, corporate governance leads to earnings management.

Temporal and Spatial Distributions of Solar Radiation with Surface Pyranometer Data in South Korea (일사 관측 자료에 의한 남한의 태양복사 시공간 분포)

  • Jee, Joon-Bum;Kim, Yeong-Do;Lee, Won-Hak;Lee, Kyu-Tae
    • Journal of the Korean earth science society
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    • v.31 no.7
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    • pp.720-737
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    • 2010
  • This study is to analyze the temporal and spatial distributions of solar radiation in South Korea. Solar radiation data is observed every minute at 22 KMA (Korea Meteorological Administration) stations using pyranometer from January 2000 to August 2007. These data were calibrated using intensive comparative observation and solar radiation model. Intensive comparative observations are accomplished at 22 KMA stations between KNU (Kangnung (Gangneung-Wonju) National University) standard and station instruments during the month of August 2007. The solar radiation of a clear sky mainly is affected by precipitable water, solar altitude and geological height. Also old (raw) data is corrected by the solar radiation model only about clear day and is revised based on the temporal trend of instrument's sensitivity decrease. At all periods and all stations, differences between raw data (13.31 MJ/day) and corrected data (13.75 MJ/day) are 0.44 MJ/ day. So, the spatial distribution of solar radiation is calculated with seasonal and annual mean, and is the relationship with cloud amount is analyzed. The corrected data show a better consistency with the cloud amount than the old data.