• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2001년도 총회 및 춘계학술발표회
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• pp.66-69
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• 2001

A subsurface containment system which is constructed by pumping a gelling liquid (Colloidal Silica) into the unsaturated medium is investigated by developing a mathematical model and conducting numerical simulations. The proposed model is verified by comparing experimentally and numerically determined hydraulic conductivities of gel-treated soil columns at different Colloidal Silica (CS) injection volumes. The numerical experiments indicate that an impermeable gel layer is formed within the time period twice the gel-point. At the Same normalized time, the CS solutions with lower NaCl concentrations result ill further migration and poor Performance in plugging the pore space.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.137-140
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• 2003

This study presents a mathematical model for simulating the fate and transport of a reactive organic contaminant degraded through cometabolism in dual-porosity soils during the in situ bioaugmentations. To investigate the effect of dual-porosity on transport and biodegradation of organic hydrocarbons, a bimodal approach was incorporated into the model. Modified Monod kinetics and a microcolony concept [Molz et at., 1986〕 were employed to represent the effects of biodegrading microbes on the transport and biodegradation of an organic contaminant. The effect of permeability reduction due to biomass accumulation on the flow field were examined in the simulation of a hypothetical field-scale in situ bioaugmentation. Simulation results indicate that the presence of the immobile region can decrease the bioavailablity of biodegradable contaminants and that the placement of microbes and nutrients injection wells should be considered for an effective in situ bioaugmentation scheme.

• The Korean Journal of Pain
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• 제12권1호
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• pp.128-131
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• 1999

Stellate ganglion block is a well established method for the management of certain pain syndromes (e.g., chronic regional pain syndrome, facial pain) in the cervicothoracic region and upper extremity. The stellate ganglion resides between the C7 transverse process and the head of the first rib. Anesthetic injections for the stellate ganglion block are typically made at the level of the transverse process of either the C6 or C7 vertebrae to avoid the pleura, vessels, and nerve roots. Method of positioning the needle tip directly at the ganglion has been described, but are problematic because of the risk of injury to or injection into adjacent structures. It is necessary to know the exact anatomic position of the stellate ganglion when permanent blockade is required by means of radiofrequency thermocoagulation. Whereas fluroscopy shows only bony feature, computerized tomography also images nerves, vessels, and lung, allowing accruate needle placement. We report a case of the percutaneous radiofrequency thermocoagulation of the stellate ganglion after computerized tomography-guided localization.

• 대한수학회지
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• 제56권1호
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• pp.25-37
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• 2019

Let G be a bipartite graph with (X, Y ) as its bipartition. Let B be a complete bipartite graph with a bipartition ($V_1$, $V_2$) such that $X{\subseteq}V_1$ and $Y{\subseteq}V_2$. A bi-packing of G in B is an injection ${\sigma}:V(G){\rightarrow}V(B)$ such that ${\sigma}(X){\subseteq}V_1$, ${\sigma}(Y){\subseteq}V_2$ and $E(G){\cap}E({\sigma}(G))={\emptyset}$. In this paper, we show that if G is a bipartite graph of order n with girth at least 12, then there is a complete bipartite graph B of order n + 1 such that there is a bi-packing of G in B. We conjecture that the same conclusion holds if the girth of G is at least 8.

• 한국응용곤충학회지
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• 제17권2호
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• pp.99-103
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• 1978

침투성 살충제 Carbofuran의 Capsule 근부처리, 액상근부주변처리 및 수면시용을 실시하였을 때 논거미(늑대거미류와 애접시거미류) 밀도에 미치는 영향을 알아보기 위해 수원과 이리에서 포장시험을 실시하였다. 1. Carbofuran의 처리에 의하여 거미의 밀도가 저하되며 관용방법인 수면처리에 비하여 근부처리의 경우 거미의 밀도가 더욱 낮었다. 2. 액상근부주변처리에 비하여 Capsule 근부처리에서 거미의 밀도가 더욱 낮었다. 3. 근부처리에서나 수면처리에서 약량이 증가함에 따라 거미밀도가 낮어졌다. 4. 무처리에서 거미밀도는 팔굉품종에서 높았고 유신품종에서 낮았으나 약제처리에서 품종간 거미밀도차이는 인정할 수 없었다. 5. 해충의 방제효과가 좋았던 Capsule 근부처리에서 거미 밀도가 낮은 이유는 식물연쇄에 의한 독성 및 살해로 고찰되었다. 6. Carbofuran의 경우 처리방법을 달리하였을 때 거미에 대한 살해를 감소시킬 수는 없을 것으로 사료된다.

• 대한치과마취과학회지
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• 제9권2호
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• pp.98-103
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• 2009

Background: Despite increasing popularity of dental implants, there is limited information on the pain experience associated with the surgical implant placement under general anesthesia. The aim of this study was to assess the characteristics of patient-reported pain and efficacy of patient controlled analgesia after implant surgery under general anesthesia. Methods: Total 39 patients who underwent implant surgery under general aensthesia were enrolled. In PCA group (n=30), patients received patient controlled analgesia (fentanyl 700 mg and ketorolac 150 mg) set to basal rate 1 ml/h, bolus 1 ml, and lockout interval 10 min. In control group (n=9), patients received ketorolac 30 mg intravenously when they feel painful. We evaluated pain intensity using VAS score at the end and after 12 hr of the operation and recorded the number of bolus injection as a surrogate of rescue therapy. We compared the VAS data, the frequency of complication between two groups. Results: The self reported pain was highest at 1 hous after surgery in both groups. However, the intensity was not severe (PCA group = 5.7, control group = 5.6), and decreased gradually thereafter. Total demand bolus number was less than 6 in nearly 65% patients. And there was no significant difference in the frequency of complications such as nausea, vomiting and dizziness between both groups. Conclusions: The Pain following the surgical placement of dental implants was generally mild and gradually decreased with time. There was no difference in complications between control group and PCA group.

• 지질공학
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• 제25권1호
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• pp.67-81
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• 2015

선형 또는 군집형으로 배치된 양수정 배열 조건에서 최적의 복수 주입정 위치를 결정하는 최적화 프로그램을 개발하였다. 다양한 목적함수를 제시하였으며 담금질모사 기법을 이용하여 목적함수를 만족시키는 주입정의 최적 위치를 평가하였다. 주입수의 회수율의 최대화를 목적함수로 설정할 경우, 우물 배열에 관계없이 두 개의 주입정을 모두 우물 군집 내부에 설치하는 것이 가장 효율적인 것으로 나타났다. 회수율의 최대화와 동시에 기존 양수정의 양수량을 고르게 증가시키는 통합목적함수를 고려하여 두 개의 주입정을 설치할 경우, 우물 배열에 관계없이 우물 배열의 양측면부가 주입정 위치로 적합한 것으로 분석되었다. 주입정 위치 최적화를 위한 다수의 시나리오 분석 결과, 최적의 결과에 근접하는 지역적 최솟값 또는 최댓값이 다수 존재하는 것으로 나타났으며, 이는 주입정의 최적 위치를 현장의 조건에 맞게 선택적으로 결정할 수 있는 개연성이 존재하는 것을 의미한다. 결론적으로, 본 연구는 담금질모사 기법이 다양한 목적함수에 부합하는 복수 주입정의 최적 위치 평가에 성공적으로 이용될 수 있음을 보여 주었다.

• 대한소아치과학회지
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• 제29권1호
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• pp.69-75
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• 2002

치과치료를 위하여 마취를 시행할 때 아동들의 주사기나 주사바늘에 대한 불편감을 감소시키기 위한 여러 방법들이 있다. 도포마취제의 사용이 한 가지 방법이다. 도포마취는 많은 임상과정, 즉 주사침 자입부위, 간단한 유치발치, 구토반응이 심한 환자에서 치과용 구내 방사선 촬영시, 인상채득 전 구토반응의 감소 목적 등으로 사용되어 왔다. 또한 소아에서 치면열구전색술과 예방심미수복술시 치아격리를 위한 러버댐 clamp의 장착은 불편감을 유발할 수 있는데, 도포마취는 이런 목적으로 러버댐 장착시 도움이 된다. 모든 구강내 도포마취제는 점막에 동등한 효과가 있다고 제안되었으나, 1980년대 개발되어 피부의 표면마취에 사용되는 EMLA(acronym for eutectic mixture of local anaesthetics)가 기존의 도포마취제보다 부착치은에 사용시 더 효과가 있다고 보고되고 있다. 본 증례에서는 침윤마취가 필요한 몇 증례에서 EMLA cream을 이용하여 국소마취를 하기 전단계, 유치 발거시, clamp 장착시, 기성관 수복 등에서 동통을 감소시킴으로써 환아의 치과 치료에 대한 불안감을 감소시키는데 매우 효과적이었기에 보고하는 바이다.

• Annals of Clinical Neurophysiology
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• 제2권2호
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• pp.119-124
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• 2000

Background : We studied EEG changes during pilocarpine-induced status epilepticus(SE), a widely used model whose EEG characteristics have not been fully described previously. Methods : Male Sprague-Dawley rats weighing 250-350 grams were used as subjects. SE was induced 5-7 days after placement of chronic epidural electrodes, using 360-380 mg/Kg pilocarpine IP. Rats were observed with continuous EEG recording following pilocarpine injection until end of the SE episode. Results : SE occurred in 10/12 rats studied. SE began with a series of discrete seizures $11.1{\pm}3.93$ minutes after pilocarpine injection. $5.2{\pm}2.71$ seizures occurred over $10.9{\pm}4.62$ minutes, until the EEG converted to a waxing and waning pattern, during which the amplitude and frequency of epileptiform activity increased. After $1.4{\pm}1.82$ minutes, a pattern of continuous high amplitude rapid spiking was established. Continuous spiking continued for $3.4{\pm}0.48$ hours with a very gradual decline in amplitude and frequency, until periodic epileptiform discharges(PEDs) began to occur. The EEG consisted primarily of PEDs for another $7.4{\pm}3.09$ hours, until electrographic generalized seizures began to occur. These continued for $5.8{\pm}4.82$ hours until death. Duration of SE was $17.0{\pm}5.88$ hours. Flat periods were a prominent feature during all EEG patterns in this model. Conclusion : EEG features distinctive in pilocarpine SE(but not unique to it) include flat periods during all patterns and resumption of continuous spiking episodes after the onset of PEDs. The sequence of discrete seizures to waxing and waning to continuous spiking to PEDs was identical to that which has been described in humans and other animal models.

• Journal of Advanced Marine Engineering and Technology
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• 제34권3호
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• pp.360-368
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• 2010

A SCR catalytic filter system is used for reducing $NO_x$ and soot emissions simultaneously from diesel combustors. The amount of ammonia (as a reducing agent) must be controlled with the amount of $NO_x$ to obtain an optimal $NO_x$ conversion. Hence, gas mixing between ammonia and exhaust gases is vital to ensure that the SCR catalyst is optimally used. If ammonia mass distribution is not uniform, slip potential will occur in rich concentration areas. At lean areas, on the other hand, the catalyst is not fully active. The better mixing is indicated by the higher uniformity of ammonia mass distribution which is necessary to be considered in SCR catalytic filter system. The ammonia mass distributions are depended on the flow field of fluids. In this study, the velocity field of gaseous flow is investigated to characterize the transport of ammonia in SCR catalytic filter system. The influence of different injection placements on the ammonia mass distribution is also discussed. The results show that the ammonia mass distribution is more uniform for the injector directed radially perpendicular to the main flow of inlet at the gravitational direction than that at the side wall for both laminar (Re = 640) and turbulent flows (Re = 4255). It is also found that the mixing index decreases as increasing the heating temperature in the case of ammonia injected at the side wall.