• Title/Summary/Keyword: Abnormal change

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Agro-Climatic Zonal Characteristics of the Frequency of Abnormal Air Temperature Occurrence in South Korea (한국의 농업기후지대별 이상기온 출현 특성 평가)

  • Shim, Kyo Moon;Kim, Yong Seok;Jung, Myung Pyo;Kim, Seok Cheol;Min, Seong Hyun;So, Kyu Ho
    • Journal of Climate Change Research
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    • v.4 no.2
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    • pp.189-199
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    • 2013
  • Using meteorological data collected from 60 observation stations during the last 38 years from 1973 through 2010, we have analysed the occurrence frequencies of abnormally low or high temperature leading to agrometeorological disasters. The analysis was made for 20 agro-climatic zones that had already been divided by the Rural Development Administration before. Since 1973, there have been an average of 1.8 frequency of abnormal air temperature occurrence per year. The frequency of abnormally high temperature occurrence has increased from an average of 0.2 per year in 1970s to 1.0 in 2000s. However, the frequency of abnormally low temperature occurrence has decreased from an average of 2.06 per year in 1970s to 0.63 in 2000s, which might be able to explain a recent global warming. The highest frequency of abnormally high temperature occurrence appeared in Taebaek Alpine zone with an average of 0.76 frequency per year. Meanwhile, abnormally low temperature was the highest in Western Sobaek Inland zone with an average of 1.43 frequency per year.

Negative Effect of Abnormal Climate on the Fruits Productivity - Focusing on the Special Weather Report - (이상기후가 과수 생산성에 미치는 악영향 - 기상특보 발효횟수를 중심으로 -)

  • Jeong, Jae Won;Kim, Seongsup;Lee, In Kyu;So, Namho;Ko, Hyeon Seok
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.4
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    • pp.305-312
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    • 2018
  • The crops cultivated and consumed in Korea require specific climate conditions corresponding to their own growth characteristics. This study aims to analyze the relationship between climate change and agricultural productivity. According to growing concern about climate change internationally, many agricultural studies are developing technology to prevent damage from climate change. Before developing technology, we should figure out what kind of crop gets huge damage and how much caused by climate change. In the context of agricultural economics, we can define the reduction of agricultural product yield as a decline in productivity. As a result, this study analyzes the effects of climate change on agricultural productivity using Stochastic Frontier Analysis model. There are several kinds of climate change phenomena that increase the inefficiency of production. In other words, there are several kinds of crops that get negative influence by climate change. The result of this study can be used as basic guideline for producers to prepare for changing weather prior to developing disaster tolerance technology coping actively with special weather report.

Seepage-Advection-Dispersion Numerical Analysis of Offshore Rubble Mound Revetment Landfill Under Transient Flow (비정상류 조건에서 경사식호안매립장에 대한 침투이류 분산해석)

  • Hwang, Woong-Ki;Kim, Hyang-Eun;Kim, Tae-Hyung
    • Journal of the Korean Geosynthetics Society
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    • v.19 no.4
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    • pp.1-9
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    • 2020
  • This study analyzes contaminant movement under transient flow in a rubble mound revetment offshore waste landfill barrier system that prevents contaminant runoff. The barrier system consists of bottom layer and side barrier. For the bottom layer system, impermeable clay layer is used. For the side barrier system, the HDPE barrier sheet (primary element) plays the main role, and the intermediate protection layer (supplementary element) is responsible for the barrier. Seepage, advection, dispersion numerical analysis was carried out using SEEP / W and CTRAN / W programs. As a result, under abnormal conditions considering the fluctuation in tidal range, the volume and direction of the flow velocity vector of the pore water change with time and the dispersion concentration of the contaminant changes. When comparing the case of 2 m tidal range and 8 m tidal range, the larger the tide value, the higher the concentration of contaminant under abnormal conditions. It was found that the rate of change of the concentration of the contaminant changed depending on the change in the tidal range, and as a result, the outflow of the pollutant was smaller than that in the steady flow state.

Showerhead Surface Temperature Monitoring Method of PE-CVD Equipment (PE-CVD 장비의 샤워헤드 표면 온도 모니터링 방법)

  • Wang, Hyun-Chul;Seo, Hwa-Il
    • Journal of the Semiconductor & Display Technology
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    • v.19 no.2
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    • pp.16-21
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    • 2020
  • How accurately reproducible energy is delivered to the wafer in the process of making thin films using PE-CVD (Plasma enhanced chemical vapor deposition) during the semiconductor process. This is the most important technique, and most of the reaction on the wafer surface is made by thermal energy. In this study, we studied the method of monitoring the change of thermal energy transferred to the wafer surface by monitoring the temperature change according to the change of the thin film formed on the showerhead facing the wafer. Through this research, we could confirm the monitoring of wafer thin-film which is changed due to abnormal operation and accumulation of equipment, and we can expect improvement of semiconductor quality and yield through process reproducibility and equipment status by real-time monitoring of problem of deposition process equipment performance.

Design and Development of a Public Waste Battery Diagnostic Device

  • Kim, Sang-Bum;Lee, Sang-Hyun
    • International Journal of Advanced Culture Technology
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    • v.10 no.3
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    • pp.281-286
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    • 2022
  • In this study, design of an intuitive internal resistance diagnostic device is to diagnose the residual capacity and aging of the battery regardless of the model and the internal protocol of the waste battery through the method of measuring the internal resistance of a waste battery. In this paper, charging and discharging were continuously performed with 2A charging and 5A discharging in order to secure data on impedance changes that may occur in the charging and discharging process of various methods. As a result of the final experiment, it was confirmed that the impedance change occurred during charging and discharging, and the amount of change increased as the charging/discharging C-rate increased. In addition, it was confirmed that the waste battery aged or abnormal cell had a large change in the impedance value.

The Value of Isotope Nephrography in Carcinoma of Cervix - Follow up Studies of Pre and Post Irradiation (자궁경부암(子宮頸部癌) 방사선치료(放射線治療) 전후(前後) Renogram의 의의(意義))

  • Yoo, H.S.;Suh, J.H.;Park, C.Y.;Choi, B.S.;Jung, S.O.;Kwak, H.M.
    • The Korean Journal of Nuclear Medicine
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    • v.9 no.1
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    • pp.51-58
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    • 1975
  • It is a great value to find an early detection of involvement of ureteric obstruction in the carcinoma of cervix. Little or no knowledge of the condition of the kidneys or the lower urinary tract are able to elucidate by the biochemical studies such as blood nitrogen or urine creatinine in carcinoma of cervix. Findings of urography delineates the condition of urinary tract stasis in the renal pelvis and ureters, however, slight stasis maybe difficult to demonstrate. On the other hand isotope nephrography is accepted as a sensitive method to observe renal function especially in regarding to the excretory function of kidney. It was attempted to analysis the findings of urography conjunction with isotope nephrography in 50 cases of unselected patients with invasive carcinoma of cervix through pre and post irradiation follow up studies. Urography was done as a routine procedure and.analysed emphasising changes of collecting systems and ureter condition. Isotope nephrography was carried out by means of $15{\mu}ci\;I^{131}$-Hippuran injected intravenously and the curves were analysed as follows. Parameter were; time of maximum amplitude ($T_{max}$), half time of maximum amplitude ($T\frac{1}{2}$), Kac and Kex value calculated from these two parameters in Tobe's method. The excretion index by Aurell defines the ratio between the maximum activity and the activity measured on the slope of the third phase ten minites after it has reached its maximum. Results: 1. 28.8% had an abnormal IVP suggestive of ureteric involvement before irradiation therapy and the patient of stage III and IV were the great part. 2. 21.7% had abnormal findings of per-irradiation renogram whom showed normal IVP. The other group showed normal IVP which group also showed normal renogram prior irradiation. 3. The more severe the ureteric involvement, the change of excretion index was greater. 4. Even in stage I and II patient, abnormal renogram was revealed in 12 cases (39.4%) among 31 cases. 5. All cases of TAH showed abnormal findings of IVP and renogram. 6. No. definite change of renogram was obtained just after the irradiation therapy (point $A:8000{\sim}9000rads,\;B:5000{\sim}6000rads,\;Co:11000{\sim}13000rads$). Each 3 month follow up study was performed and comparing with preirradiation study which showed significant changes of excretion index of renogram were 42.8% in $6{\sim}9$ month follow-up and 75% in $9{\sim}12$ month, respectively. 7. It seems to be important to observe the parameter Kex and excretion index of renogram to determine early abnormality of kidney excretory function by means of post-irradiation follow up study.

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A Clinical Study of Acute Carbon Monoxide Intoxication (급성 일산화탄소 중독증 환자의 임상적 고찰)

  • Choi, Kyong-Chan;Park, Mee-Yeung;Hah, Jung-Sang;Byun, Yeung-Ju;Park, Choong-Suh
    • Journal of Yeungnam Medical Science
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    • v.8 no.1
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    • pp.86-97
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    • 1991
  • To obtain the basic data of prognosis of acute carbon monoxide(CO) intoxication, one hundred and sixteen cases of CO intoxication defined by carboxyhemoglobin(COHb) and admitted via emergency room of Yeungnam University Hospital from Oct. '85 to April' 89 have been clinically analyzed and evaluated, including delayed postanoxic encephalopathy(DPE) and the following results were obtained. 1. The ratio of male to female was 1:1.5 and mental state was drowsy mostly(26.2% of 116 cases) 2. The more disturbed the mental state, the more decreased was the arterial pH and $PaCO_2$, which may be the result of metabolic acidosis. 3. The early laboratory findings in patients of CO intoxication were as follows : leukocytosis-65.5%, increase of hematocrit-23.3%, hyperglycemia-19.8%, increase of GPT-19.8% increase of creatinine-0.9%, and glucosuria-12.1%. 4. The early findings of EKG were abnormal in 35.3% : change of rhythm-25.0%, abnormal ST segment-15.5% (change of rhythm and abonormal ST segment-5.2%) but the conduction disorder was not present. 5. The abnormal EEG above mild degree was 93.1%, of which moderate was most frequent(80.2%). 6. The incidence of DPE was 7.8% among all admitted CO patients. DPE cases had long duration of exposure time(8 hours), severe leukocytosis(20,000) and an abnormal EEG(MA).

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Long-term Performance of Stock Splits (주식분할의 장기성과)

  • Byun, Jong-Cook;Jo, Jeong-Il
    • The Korean Journal of Financial Management
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    • v.24 no.1
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    • pp.1-27
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    • 2007
  • In this study, we investigated the market long-term performance of stock splits by using the Korean Stock Market data from 1998 through 2002. We measured the performance by the event-time portfolio approach with the buy-and-hold abnormal return(BHAR) and the cumulative average abnormal return(CAAR). Also, the calendar-time portfolio approach with one-factor and three factor model were used for avoiding the misspecification model problem. The first of main results in this study was that the stock splits had significantly positive abnormal returns around the month of the stock splits announcements. However, the period BHAR and CAAR after the announcement month were significantly negative. This negative long-term abnormal returns were confirmed by the calendar-time portfolio approach. The results suggested that the abnormal return followed by the stock splits seemed to be positive in the short-term period. Second, there was no the difference of the long term performance between the high and the low split ratios. The operating income performance in the periods followed by the stock splits announcements grew worse. Therefore, the signalling effects, the managers of the firm under considering the stock splits would make use of splits as a form of signals for the upward changes in the cash flow or profits, could not be found. Finally, in contrast to Fama, Fisher, Jensen and Roll(1969), the significant negative abnormal returns following the stock splits were still found irrespective of the change of dividend payout ratio.

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Electrophysiological Analysis in Diabetic Patients with Abnormal Sensation and Pain (이상감각과 통증을 호소하는 당뇨병 환자의 전기생리학적 특징 분석)

  • Yang, Jiwon;Lee, Yeong-Bae
    • Science of Emotion and Sensibility
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    • v.19 no.4
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    • pp.111-118
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    • 2016
  • Patients with type 2 diabetes mellitus can complain of abnormal sensation and pain which derived from the peripheral nerve damage. Various words used to be describe abnormal sense and pain, such as sharp, hot, dull, cold, sensitive, and itch. To diagnose diabetic peripheral neuropathy, several screening instruments (Neuropathic Pain Scale, NPS; Michigan Neuropathy Screening Instruments, MNSI) and electrophysiological study can be used. In this study, we aim to analyze and compare the clinical and electrophysiological characteristics of 11 patients with diabetes mellitus and abnormal sense/pain (Disease Group, DG) and 10 patients with diabetes mellitus and normal sense (Control Group, CG). In addition, we aim to reveal correlation between NPS subscore and electrophysiological parameters. As a result, the scores of NPS and MNSI in DG were significantly higher. In nerve conduction study, median motor nerve and peroneal nerve showed significant functional change. Also, median motor nerve, posterior tibial nerve and sural nerve showed negative correlation as NPS subscore increased. These results mean increased pain can be associated with abnormal nerve function. It needs to be further explored for larger size of subjects to get confirmative results.

Understanding on MR Perfusion Imaging Using First Pass Technique in Moyamoya Diseases (Moyamoya 질환에서 1차 통과기법을 이용한 자기공명관류영상의 이해)

  • Ryu, Young-Hwan;Goo, Eun-Hoe;Jung, Jae-Eun;Dong, Kyung-Rae;Choi, Sung-Hyun;Lee, Jae-Seung
    • Korean Journal of Digital Imaging in Medicine
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    • v.12 no.1
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    • pp.27-31
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    • 2010
  • The purpose of this study was to investigated the usefulness of MR perfusion image comparing with SPECT image. A total of pediatric 30 patients(average age : 7.8) with Moyamoya disease were performed MR Perfusion with 32 channel body coil at 3T from March 01, 2010 to June 10, 2010. The MRI sequences and parameters were as followed : gradient Echo-planar imaging(EPI), TR/TE : 2000ms/50ms, FA : $90^{\circ}$, FOV : $240{\times}240$, Matrix : $128{\times}128$, Thickness : 5mm, Gap : 1.5mm. Images were obtained contrast agent administrated at a rate of 1mL/sec after scan start 10s with a total of slice 1000 images(50 phase/1 slice). It was measured with visual color image and digitize data using MRDx software(IDL version 6.2) and also, it was compared of measurement with values of normal and abnormal ratio to analyze hemodynamic change, and a comparison between perfusion MR with technique using Warm Color at SPECT examination. On MR perfusion examination, the color images from abnormal region to the red collar with rCBV(relative cerebral blood volume) and rCBF(relative cerebral blood flow) caused by increase cerebral blood flow with brain vascular occlusion in surrounding collateral circulation advancement, the blood speed relatively was depicted slowly with blue in MTT(Mean Transit Time) and TTP(Time to Peak) images. The region which was visible abnormally from MR perfusion examination visually were detected as comparison with the same SPECT examination region, would be able to confirm the identical results in MMD(Moyamoya disease)judgments. Hymo-dynamic change in MR perfusion examination produced by increase and delay cerebral blood flow. This change with digitize data and being color imaging makes enable to distinguish between normal and abnormal area. Relatively, MR perfusion examination compared with SPECT examination could bring an excellent image with spatial resolution without radiation expose.

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