• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.3
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• pp.1-14
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• 2019

With a view to developing a database of death years of Korean firs (Abies koreana) at Yeongsil in Mt. Halla and investigating their abrupt inter-annual growth reduction tree-ring analysis was employed. To this end, 10 living trees (YSL) were selected to establish a master chronology and 20 dead trees were used to date their dead years. To investigate the difference in death years by death types, 10 trees, which remained standing (YSSD) out of the 20 dead trees were selected. The rest 10 dead trees were already fallen (YSFD). Two increment cores per tree at breast height were extracted in contour direction using an increment borer. A 106-year master chronology (1911-2016) was successfully established from the 10 YSLs. Through cross-dating between individual YSSD time series and the master chronology, it was verified that 1 YSSD was dead in summer 1978, 1 YSSD between autumn 1999 and spring 2000, 2 YSSDs in summer 2007, 1 YSSD in summer 2010, 1 YSSD in summer 2012, and 1 YSSD in summer 2013. The youngest tree rings of 2 YSSDs having no bark were in 1977 and 2002. For the YSFDs, it was verified that 1 YSFD was dead between autumn 1997 and spring 1998, 1 YSFD between autumn 2001 and spring 2002, 2 YSFDs between autumn 2009 and spring 2010, 1 YSFD in summer 2010, and 2 YSFDs between autumn 2012 and spring 2013, while the youngest tree rings of 2 YSFDs having no bark were in 1989 and 2004. To note, the death years of two trees, one from each death type (YSSD and YSFD), could not be verified due to poor cross-dating with the master chronology. The inter-annual growth reductions of YSSD and YSFD occurred more frequently and intensively than YSL. Typically, the YSFD showed the most frequent and intensive inter-annual growth reduction. On comparing the inter-annual growth reductions with the corresponding records of typhoons however we could not find any reliable relationship. Finally, from prior reports and results of the current study it can be concluded that the death and abrupt growth reduction of korean fir at Yeongsil in Mt. Halla are not caused by only a certain environmental factor but various factors.

• Journal of Chest Surgery
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• v.20 no.1
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• pp.71-80
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• 1987

Twenty six patients were operated a total correction of tetralogy of Fallot between Jan., 1984 and July, 1985 at the Dept. of thoracic and cardiovascular surgery, Chonnam University Medical School, and a comparison between the survived group [n = 18] and the dead group [n = B was performed to detect factors influencing laboratory data, cineangiographic findings, operative findings and methods, and pump time. Following results were obtained, 1. There was no significant difference between two groups in the preoperative P.O2 and hematocrit level. 2. The size of the interventricular defect was not related to the operative mortality. 3. There was a significant difference in mortality rate between combined type of stenosis of pulmonary artery, valve and infundibulum and other types of right ventricular outflow tract stenosis. 4. There was a significant difference in mortality rate between the transannular patch reconstruction and other types of operative procedure. 5. There was no significant difference between two groups in total bypass time and aortic time. 6. There was no significant difference between two groups in left ventricular end diastolic volume and right ventricular end diastolic volume. 7. The operative mortality was related to the ratio of the diameter of the pulmonary valve annulus or each pulmonary artery to the ascending or descending aorta in cineangiographic findings, but there was no statistical significance of which probably is due to the lack of the total number of patients.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.3
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• pp.1-7
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• 2002

This paper presents a new PLL clock generator that can improve a jitter noise characteristics and acquisition process by designing a multi-PFD(Phase Frequency Detector) and an adaptive charge pump circuit. The conventional PLL has not only a jitter noise caused from such a demerit of the wide dead zone and duty cycle, but also a long delay interval that makes a high speed operation unable. An advanced multi-structured PFD circuit using the TSPC(True Single Phase Clocking) circuit is proposed, in which it shows an excellent functionalities in terms of the jitter noises by designing its circuit with the exact dead zone and duty cycle. Our new designed adaptive charge pump in the loop filter of a PLL can improve an acquisition characteristic by adaptively increasing of current. The Hspice simulation is done to evaluate the performance of the proposed circuit. Simulation result shows that our PLL has under 0.01ns in the dead zone, no influence from the duty cycle of input signals and under 50ns in the acquisition time. This circuit will be able to be used in develops of high-performance microprocessors and digital systems.  

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.358-363
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• 2003

Optimal tuning plays an important role in operations or tuning of the complex process such as the main steam temperature of the thermal power plant. However, it is very difficult to maintain the steam temperature of power plant using conventional optimization methods, since these processes have the time delay and the change of the dynamic characteristics in the reheater. Up to the present time, the Pm controller has been used. However, it is not easy to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error. This paper suggests immune algorithm based tuning technique for PID Controller on steam temperature process with long dead time and its results are compared with genetic algorithm based tuning technique.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.2232-2241
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• 2010

A case study of fire risk analysis was conducted for train coach which has no gangway doors between coaches. The analysis boundary was limited to the time of outgoing from the coaches for it was train fire risk analysis. ASET(available safe egress time) and RSET(required safe egress time) methodology was used for calculating the dead. 4 liters of gasoline and cable fire at the electric cabinet and the standard fire of EN 45545 were selected for the fire sources. The fire were considered to be occurred at 3 different locations in the car. The train had 3 cases of driving scenarios. The result of all event was summarized for remained tunnel and station egress step.

• The Korean Journal of Malacology
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• v.26 no.3
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• pp.179-183
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• 2010

In other to understand the effect of yellow soil to mortality of Korean scallops, P. yessoensis, We investigated its mortality at indoor tanks. The environmental conditions such as water temperature, Salinity, Do and pH were continued constantly during the experimental periods. The 100% of survival rate showed in two experiments groups such as 0.1% and 0.4% of concentration of yellow soil and the other groups as 0.05% and 0.2% of concentration of yellow soil was appeared one dead scallop at each group for 8 days of the experiment periods. the gills of scallop in high concentration of yellow soil (0.2% and 0.4% groups) were covered by yellow soil particles so that this group's scallop should be got a high stress from yellow soil. I think this situation will be more continued for long time the scallop will become to dead. The results of bacteriological analysis did not isolated from haemolymph of scallops and no Perkinsus infectious disease in scallops and the scallops showed necrosis and degeneration on digestive grand and gills of scallop.

• SUVANNABHUMI
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• v.16 no.1
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• pp.103-123
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• 2024

The traumatic experiences of people from peripheral islands are susceptible to mnemocide. Such erasure of memory is facilitated by "defensive and complicit forgetting," which, according to Aleida Assmann, leads to "protection of perpetrators." My paper reflects on the vulnerability of traumas from the islands to mnemocide by looking into [1] the massacre of communists and civilians on Jeju Island, South Korea in 1948 as described in Hyun-Kil Un's short story "Dead Silence" (2017; English trans.) and [2] the eviction of residents and indigenous people from Calauit Island, Philippines for the creation of a safari in 1976 as imagined in Annette A. Ferrer's "Pablo and the Zebra" (2017). In "Dead Silence," I direct the attention to how to the execution of the villagers-witnesses to the death of the communist guerillas-is a three-pronged violence: it is a transgression committed against the innocent civilians; an act of "erasing traces to cover up" the military crackdown on the island; and, by leaving the corpses out in the open, a display of impunity. In "Pablo and the Zebra," I second that both residents (i.e., humans and animals) experience post-traumatic stress because of their respective displacements; thus, the tension between them has got to stop. Curiously, while it concludes with a reconciliatory gesture between an elder and a zebra, no character demanded a reparation for their traumatic past per se. Could the latter be symptomatic of a silence that lets such violence "remain concealed for a long time"?

• Journal of The Korean Society of Clinical Toxicology
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• v.5 no.1
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• pp.1-7
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• 2007

Purpose: The aim of this study was to evaluate the characteristics and the prognostic factors of carbamate poisoned patients who visited emergency departments. Methods: From August 2005 to July 2006, we investigated the demographic feature, dose of exposure, time of exposure, alcohol intake, route of exposure, reason of exposure, site of exposure, pre-existing medical condition, time from exposure to emergency department (ED), transfer from other hospitals, vital sign at ED arrival, symptom or sign at ED arrival, and result of care of the patients who visited the ED of thirty-eight hospitals in Korea. According to the result of care, we divided the patients into two groups, the survival and the dead. To evaluated the prognostic factors, we calculated the odds ratio of each factor for the survival. Results: Among the sixty-eight patients, fifty-five patients (80.9%) were survival and thirteen patients (19.1%) were dead. The patients in the dead were older than the patients in the survival. The Glasgow coma scale (GCS) of the patients in the dead was lower than the GCS in the survival. The odds ratio of the GCS at ED arrival for the survival was 1.58 (95% CI; 1.23-2.05). Other factors showed no statistical significances. Conclusion: The GCS at emergency department arrival was the prognosis factor of the carbamate poisoned patients who visited emergency departments. If the carbamate poisoned patients showed altered mentalities, they should be provided intensive care, immediately.

• Toxicological Research
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• v.16 no.3
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• pp.239-253
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• 2000

This study was carried out to evaluate the three months subacute intravenous toxicity of water soluble dimethyl dimethoxy biphenylate derivative (DDB-S), a newly formulated therapeutic agent for hepatitis, in Beagle dogs. Groups of 12 male and 12 female dogs were given different dosage of DDB-S, 10 mg/kg/day (high dose group), 5 mg/kg/day (middle dose group), 2.5 mg/kg/day (low dose group) and 0 mg/kg/day (control group) for three months by intravenous route. 1n the three months intravenous toxicity study, there were neither dead animals nor significant changes of body weights during the experimental period. 1n addition to, no significant DDB-S related changes were found in clinical signs, urinalysis and other findings. Statistical changes were observed in hematological. biochemical, partial thromboplastin time (PIT) and organ weight parameters of treated groups. However, these alteration had no relationship with dosage. No histopathological lesions were observed in both control and treated animals. Above data suggest that no observed adverse effect level of test materials in Beagle dogs might be over 10 mg/kg/day in this study.

• Korean Journal of Environmental Agriculture
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• v.24 no.1
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• pp.6-11
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• 2005

A prototype surface flow constructed wetland was built in the upstream area of reclaimed tidal lands to improve the water quality of Lake Sihwa by treating severely polluted stream water. In this study, a tracer test using rhodamine-WT was performed to investigate the flow characteristics and to quantify the observed hydraulic residence time (HRT) for a high-lying cell in the Banwol wetland of the Sihwa constructed wetland. The tracer test indicated that even if flow was mainly observed in the open water area of the Banwol wetland, water flowed continuously in the vegetative area and there was no dead zone. The calculated HRT (51.3 hrs), calculated by dividing the wetland volume by the wetland inflow, exceeded the observed HRT (38.7 hrs), since the short-circuiting of flux resulting from irregular topography and vegetation was not reflected in the calculated HRT. The exit tracer concentration curves were reproduced well by both the plug flow with dispersion and tanks-in-series models, indicating that the performance of the Banwol wetland can be estimated accurately using these models.