• Korean Journal of Soil Science and Fertilizer
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• v.46 no.6
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• pp.610-614
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• 2013

Massive intercalation of urea into montmorillonite (MUCH) was recently proposed to enhance urea use efficiency through smart suppression of emission of $NH_3$ and NOx. This study was to synthesize citrate-incorporated MUCH (Cit-MUCH) which can enhance suppression of $NH_3$ volatilization. The XRD pattern of Cit-MUCH was very similar to that of MUCH to indicate successful incorporation of citric acid into MUCH. Incorporation of citric acid was confirmed by the existence of $COO^-$ symmetric stretching vibration. During the initial 4 days after application, $NH_3$ volatilization from both bare and perilla-planted soils was much more suppressed by application of Cit-MUCH than MUCH. A peak volatilization rate decreased from 28.3 N mg $m^{-2}\;h^{-1}$ of MUCH-broadcasted soil to 22.2 N mg $m^{-2}\;h^{-1}$ of Cit-MUCH-broadcast soil. $NH_3$ volatilization was less in planted soil than bare soil for 72 hrs after application. These results showed that incorporation of citric acid led to increase in suppression of ammonia volatilization from urea-applied soils.

• Nuclear Engineering and Technology
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• v.26 no.1
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• pp.1-8
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• 1994

The flame speed correlation considering thermal-hydraulic phenomena under severe accidents is proposed and correction coefficients are defined. This correlation modifies the pressure dependency in Iijima-Takeno correlation and adds the steam suppression effects to it in the anticipated hydrogen and steam concentration ranges under severe accidents. The existing models of flame speed due to hydrogen combustion under severe accidents are based on the experiments which were performed merely at room temperature and atmospheric pressure. They have difficulty in predicting a accurate flame speed in a case of high temperature and pressure during severe accidents. Thus the flame structure is assumed as a prerequisite to the reliable determination of flame speed and theoretical model is developed. To examine the validity, flame speeds in various conditions calculated by this model are compared with those obtained by the calculation of the existing correlations of the codes such as improved HECTR and MAAP. Also the steam suppression ratio is quantified and the steam suppression coefficient is defined as a composition of mixture. Initial temperature and pressure dependencies are investigated and correction coefficents are determined. More experimental studies can be recommended to improve this correlation to its further works.

• Journal of Korean Neurosurgical Society
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• v.30 no.12
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• pp.1381-1387
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• 2001

Objective : Endodermal sinus tumor or yolk sac tumor is an uncommon malignant germ-cell neoplasm. This tumor was originally described as a germ cell tumor of the ovary or the testis. Intracranial endodermal sinus tumor is extremely rare and usually develop in the pineal or suprasellar regions. The authors evaluated the effect of adjuvant therapy(chemotherapy combined with radiotherapy) and radical removal of intracranial endodermal sinus tumors. Material and Methods : Between 1996 and 2001, four patients of intracranial endodermal sinus tumor were diagnosed with tumor marker(AFP) and biopsy. Three patients were treated with surgical removal and chemotherapy with cisplatin($20mg/m^2$), etoposide($100mg/m^2$) and bleomycin($15mg/m^2$) as well as external beam radiation therapy. We compared the management problems for these tumors. Result : In all three patients the tumor size and the level of tumor marker decresed during initial adjuvant therapy. However, Tumors showed regrowth with elevated AFP of serum and CSF possibly related to delayed chemotherapeutic treatment or inadequate administration of chemotherapeutic drugs due to severe bone marrow suppression. An additional chemotherapy and external radiation therapy were given, but tumors could not be controlled with leptomeningeal seeding. Conclusion : Radiotherapy is considered to be less effective. The combination chemotherapy with PVB(cisplatin, vinblastine, bleomycine) or PE(cisplatin, etoposide) is considered to be value in prolongation of the survival rate. But the role of chemotherapy in this tumor has not yet been clarified due to bone marrow suppression and drug resistance. Further study with large series of this tumor is necessary to establish the optimal management.

• Fire Science and Engineering
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• v.21 no.3
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• pp.8-14
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• 2007

The manual was proposed for individual role, according to the stages of forest fire suppression at forest fire occurrence site, for forest fire crew who has a responsibility of national forest office. The scopes of this manual are (1) apply to initial attack before arriving helicopter, (2) apply to ground fire fighting support with air attack, (3) apply to mop-up after withdraw air attack, (4) apply to night suppression when air attack is impossible. This manual is arranged for incident commander or ground fire fighter duties from the 1st stage of acceptance of forest fire to the 10th stage of withdraw of helicopter. This was developed for the purpose of every awareness of the crews and therefore of fire reduction of damage of lives, properties and forest through systematic and rapid response to forest fire.

• Journal of Korean Tunnelling and Underground Space Association
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• v.23 no.6
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• pp.503-516
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• 2021

Autonomous fire detection and suppression system requires advanced technology for complex detection technology and injection/control technology for accurate hitting by fire location. Also, foam spraying should be included to respond to oil fires. However, when a single spray monitor is used in common, water and foam spray properties appear different, so for accurate fire suppression, research on the spray trajectory and distance will be required. In this study, experimental studies and numerical analysis studies were combined to analyze the foam spray characteristics through the spray monitor developed for the establishment of an autonomous fire extinguishing system. For flow analysis of foam injection, modeling was performed using OpenFOAM analysis software, and the commonly used foaming agent (Aqueous Film-Forming Foam) was applied for foam properties. The injection distance analysis was performed according to the injection pressure and the injection angle according to the form of the foam, and at the same time, the results were verified and presented through the injection experiment.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.237-242
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• 1997

Comparative studies on suppression possibility with three phytoseiid mite species (An.thly,seiu,sw omersleyi Schicha. A. ,fidIrrc~i.Gs arman and T\ulcornerphlorlrotiiu.s oc~c~idetitaliNs esbit) to the two-spotted spider mite (Te~trrrt~yc.Iir~l~l\ulcorner.i\c .(re Kwh) on kidney bean leaves in field and greenhouse were carried out. In the field experiments with the initial prey -predator ratio of 4 : 1. I0 : I and 20: I . A. ,firllrrcis suppressed successfully the prey populations at all three ratios 17 days after the initial infestation. A. wornc,r-;leyi \uppressed the prey population only at the ratio of 4 : 1, while T. oc~c~ideritcr1iw.s as unable to suppress the prey population at all tested ratios. In the greenhouse experiments with the initial prey-predator ratio of 10: 1, A. jil1ltrci.s could suppress the prey population continuously during the infestation period. A. ~~otnc~r,slceoyuil d suppress the prey population for 13 days after the initial infestation, while T. occie1mttrli.s could suppress the prey population for 8 - 23 days after the initial infestation.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.5
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• pp.419-429
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• 2016

In a bid to avoid the economic loss resulting from traffic jam in urban area, a deep underground road at 40 m depth has been considered and the first class disaster prevention facilities shall be applied according to domestic guideline. Automatic-monitoring fire extinguishing system designed to use for fire fighting has been widely applied at home and abroad. Recently development and commercialization through theoretical and experimental research to apply to road/railroad sector have been underway. Based on such performance of automatic fire extinguishing system, technical/economic analysis of existing water spray systems was conducted and as a result, it has demonstrated the superiority in terms of fire suppression as well as in cost efficiency. Then to commercialize this system, more diverse studies that will incorporate the characteristics of domestic tunnels are needed and should the system be promoted through institutional improvement, it's expected to become one of the advanced nations with own original technology in a life safety system industry throughout the world.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1817-1824
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• 2014

The adsorption characteristics of chromium (VI) and phosphate on calcined Mg-Al-$CO_3$ layered double hydroxides (CLDH) were investigated in single and binary systems. A series of batch experiments were performed to study the influence of various experimental parameters. In this study, CLDH exhibited a high adsorption capacity for Cr (VI) and P in a single system. The experimental data were close to the theoretical adsorption capacity given by the Langmuir isotherm, the calculating adsorption capacities of Cr (VI) and P were up to 70.42 mg/g and 97.09 mg/g, respectively. It was found that the initial pH was approximately 6 and it took 24 h to reach equilibrium when P and Cr (VI) were added simultaneously. The experimental data were best fitted by a pseudo-second-order kinetics model. Competitive adsorption between Cr (VI) and P existed in the binary system. The presence of Cr (VI) had no significant influence on P adsorption. However, the suppression of Cr (VI) adsorption was obvious when the initial concentration of P was up to 10 mg/L with a concentration of 0.5 g/L of CLDH.

• Korean Journal of Veterinary Research
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• v.55 no.4
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• pp.215-219
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• 2015

Cardiopulmonary depression of long-term constant rate infusion (CRI) administration of multiple analgesic drugs is important, especially in critically ill dogs. Therefore, this study was conducted to evaluate the effects of lidocaine, ketamine or combined lidocaine-ketamine combination CRI treatment on vital signs and left ventricular (LV) function in healthy dogs. Six adult Beagle dogs were administered either ketamine (initial loading dose of 0.5 mg/kg followed by $10{\mu}g/kg/min$ CRI), lidocaine (initial loading dose of 2 mg/kg followed by 0.025 mg/kg/min CRI), or combined lidocaine-ketamine intravenously. Arterial blood pressure (BP), heart rate (HR), respiratory rate (RR), body temperature (BT) and echocardiographic LV dimensions were measured before administration of medications, immediately after administration of drugs, and then every 10 min for 2 h. There were no significant changes in HR, RR, BT and BP after the administration of either lidocaine CRI, ketamine CRI, or combined lidocaine and ketamine CRI. There were also no significant changes in LV dimensions and stroke volume. The results revealed that treatment with either lidocaine, ketamine or combined lidocaine-ketamine may not cause cardiopulmonary suppression in healthy dogs.

• Korean journal of applied entomology
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• v.35 no.2
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• pp.126-131
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• 1996

These experiments were conducted in the laboratory conditions to determine the prey consumption of a predaciousphytoseiid mite, Amblyseius womersleyi Schicha, and its ability to regulate the population of tea redspider mite, Tetranychus kanzawai Kishida. The functional response curve of the adult A. womersleyi to thedensity of eggs, larvae, and nymphs of T. kanzawai indicated Holling's Type 11: the consumption of prey bythe adult A. womersleyi increased with the prey density but the consumption rate decreased. The critical initialratio to suppress the prey population by the predator seemed to be 32:l @rey:predator) at 25"C, and 16:l at20$^{\circ}$C on kidney bean plant. The predator could not regulate any initial ratio of the prey population at 15$^{\circ}$C.^{\circ}$C.