• Journal of Biosystems Engineering
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• v.19 no.1
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• pp.17-21
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• 1994

This reasearch was performed to provide the fundamental intonation for the mechanization of Korean pine cone harvest when the shoot shearing method is adopted. Shear force and stress of pine cone shoots were measured and analyzed for this purpose. Samples are selected along their harvesting time and tested in 17 levels of shoot diameter from 10 to 26mm with 1mm increment. 1) Shear force-deformation characteristics showed that shoot reached its rupture point after 2 to 4 of bio-yield points. It was supposed that these multiple bio-yield points were caused by the discrete compression of wood parts which are composed of water, nutrient, resin, etc. 2) Required shear force to shear shoot was proportional to the square of shoot diamter, however, shear force for shoots of early harvesting time(Aug. 31) was proportional to the shoot diameter. Variance of shear force was increased as the harvesting time was delayed. Shear forces were distributed from 468N(Aug. 31, 12mm dia) to 4153N(Aug. 31, 26mm dia) disregarding the sampling date. 3) The average shear stresses by sampling dates were 744,822, and 883N/m2, respectively, and for the earlier shoot samples shear stress was quite smaller than the others. Shear stress was proportional to shoot diameter squared, and the effect of shoot diameter on the shear stress was decreased as harvesting time was delayed.

• Korean Journal of Plant Resources
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• v.10 no.4
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• pp.314-318
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• 1997

This experiment was carried out to analyze the essential oils from different parts of Perilla frutescens spp. And to know change of the oil content by a diffenent leaf picking time. The analysis of the essential oils was done with gas chromatography(GC),and the results are as follows. Perilla frutescens spp. contained essential oils mostly in their leaves and stems, although their roots also contained the oils. It was suggested that the optimum leaf-picking time of perilla frutescens var. viridis Mak. on the basis of total essential oils was their flowering period around Aug. 24, and that of Perilla frutescens var. for acuta Kudo was Sep. 14. On the basis of perillaldegyde the optium leaf-picking time of Perilla frutescens var. viridis Mak. and Perilla frutescens var. acuta Kudo was Aug. 24. and Aug. 4. respectively.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.426-432
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• 2013

The mechanisms concerning C-Cl activation of $CCl_4$ by $CHBr^{{\cdot}-}$ and $CBr{_2}^{{\cdot}-}$ have been comparatively investigated in theory. Optimized geometries and frequencies of all stationary points on PES are obtained at the BhandHLYP/aug-cc-pVTZ level of theory, and then the energy profiles are refined at the QCISD(T) method with the aug-cc-pVTZ basis by using the BhandHLYP/aug-cc-pVTZ optimized geometries. Our calculated findings suggest that in the title reactions the major mechanisms consist of both Cl-abstraction and $S_N2$ substitution reactions. Also, a succeeding pathway described by electron transfer was revealed before the initial Cl-abstraction products separate. Those are consistent with relevant experimental results.

• Journal of the Korean Chemical Society
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• v.59 no.5
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• pp.387-396
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• 2015

The DFT and ab initio calculations have been performed to elucidate hydrogen interaction of HOOO-(H₂O)_n (n=1~5) clusters. The optimized geometries, harmonic vibrational frequencies, and binding energies are predicted at various levels of theory. The trans conformer of HOOO monomer is predicted to be thermodynamically more stable than cis form at the CCSD(T) level of theory. For HOOO-(H₂O)_n clusters, the geometries are optimized at B3LYP/aug-cc-pVTZ and CAM-B3LYP/aug-cc-pVTZ levels of theory. The binding energy of HOOO-H₂O cluster is predicted to be 6.05 kcal/mol at the MP2//CAM-B3LYP/ aug-cc-pVTZ level of theory after zero-point vibrational energy (ZPVE) and basis set superposition error (BSSE) correction. The average binding energy per H₂O is increased according to adding a H₂O moiety in HOOO-(H₂O)_n clusters up to 7.2 kcal/mol for n=5.

• Journal of the Korean earth science society
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• v.33 no.2
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• pp.148-161
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• 2012

The intensive observation (ProbeX-2010) with 6-hour launches of radiosonde was performed over Seoul metropolitan area (Dongducheon, Incheon Airport, and Yangpyeong) from 13 Aug. to 3 Sep. 2010. Five typical heavy rainfall patterns occurred consecutively which are squall line, stationary front, remote tropical cyclone (TC), tropical depression, and typhoon patterns. On 15 Aug. 03 KST, when squall line developed over Seoul metropolitan area, dry mid-level air was drawn over warm and moist low-level air, inducing strong convective instability. From 23 to 26 Aug and from 27 to 29 Aug. Rainfall event occurred influenced by stationary front and remote TC, respectively. During the stationary frontal rainy period, thermal instability was dominant in the beginning stage, but dynamic instability became strong in the latter stage. Especially, heavy rainfall occurred on 25 Aug. when southerly low level jet formed over the Yellow Sea. During the rainy period by the remote TC, thermal and dynamic instability sustained together. Especially, heavy rainfall event occurred on 29 Aug. when the tropical air with high equivalent potential temperature (>345 K) occupied the deep low-middle level. On 27 Aug. and 2 Sep. tropical depression and typhoon Kompasu affected Seoul metropolitan area, respectively. During these events, dynamic instability was very strong.

• Magazine of the Korean Society of Hazard Mitigation
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• v.3 no.4 s.11
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• pp.13-25
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• 2003

• Journal of Chest Surgery
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• v.17 no.1
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• pp.26-31
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• 1984

From Jan. 1962 to Aug. 1983, one hundred patients with cyanotic heart disease underwent various palliative operations at the department of thoracic and cardiovascular surgery, S.N.U.H. In the period from Jan. 1962 to Dec. 1973, in which the open heart surgery was not routinely performed, sixty-two operations including 2 cases of second shunt operation were performed in sixty patients, and all of them were tetralogy of Fallot except three cases. Various palliative procedures such as Glenn, Brock, Waterston and Blalock-Taussing operation were used in this period with overall mortality rate of 16%. In the period from Jan. 1980 to Aug. 1983, forty patients with cyanotic heart disease were operated and majority of them was complex anomalies. Only Blalock-Taussing operation was used in this period with a mortality rate of 20%. These two groups of patients were compared according to age, diagnosis and results of operations, and it appears that Blalock-Taussing operation is effective palliation for patients with cyanotic heart disease, especially with complex anomaly, with an acceptable mortality.

• Journal of Chest Surgery
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• v.20 no.2
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• pp.309-316
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• 1987

Since the first report of successful ligation of patent ductus arteriosus in 1939, it`s surgical intervention has become a routine and relatively safe procedure. During the past ten years from Aug. 1975 to Aug. 1985, 107 cases were operated on for a patent ductus arteriosus at the Department of thoracic and Cardiovascular Surgery, School of Medicine, Kyungpook National University. Clinical analysis of these cases was performed. Mean age at operation was 9.4 years, ranging from 20 months to 32 years. Sex ratio of female to male was 1.8;1. Most common symptoms were frequent respiratory infection, exertional dyspnea, and palpitation. Diagnosis was made by auscultation, 2 dimensional echocardiography, cardiac catheterization, and cineangiocardiography. A moderate to severe pulmonary hypertension was found in 42 cases [49.4%] in cardiac catheterization. Operative methods were multiple ligation of paten`. ductus arteriosus with or without Dacron or Teflon wrapping in 72 cases [68%], and division and suture in 34 cases [32%]. There were three operative deaths [2.8%]. The causes of death were hemorrhage from tearing of aorta, low cardiac output, and arrhythmia. All of these cases had moderate degree of pulmonary hypertension.

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.177-182
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• 1995

Amphibian and Reptilian fauna in Chuwangsan National Park was carried out both Apr. 28, 1994 - Apr. 30, 1994 and Aug. 4, 1994-Aug. 5, 1994. 7 species in 5 Families in Amphibia and 7 species in 3 Families in Reptilia were observed in this survey. Rana dyhowskii in Amphibia and Rhabdophis tigrinus tigrinus in Reptilia were revealed dominant species in Chuwangsan National Park. The results in this survey would be use to baseline data significantly after the project of construction works in Chuwangsan National Park.

• Korean Journal of Environment and Ecology
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• v.10 no.2
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• pp.184-190
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• 1997

Herpetofauna in Soraksan National Park was carried out both Apr. 27, Apr. 28, 1996 and Aug. 19, Aug. 20, 1996. 6 stecies of 4 Families in Amphibian and 2 species of 2 Families in Reptilian were observed in this survey. It was observed relatively poor biota to other National Park that caused to excessive visitor and impacts by divelopments. Onychodactylus fischeri which was revealed Specific Endangered Animal assigned by Minister of Environmemt distributed abundantly along the Chohangnyong. So Chohangnyong should be conserved by prolonging the Year of Natural Rest.