• Journal of the Korean Electrochemical Society
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• v.9 no.3
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• pp.132-134
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• 2006

The main component governing selectivity in ion-selective electrodes and optodes is the ionophore. For this reason, a member of natural products that possess selective ion-binding properties have long been sought after. By applying this principle, the performance of tetracycline used as neutral carriers for cation selective polymeric membrane electrode was investigated. The cation ion-selective electrode based on tetracycline gave a good Nernstian response of 26.6 mV per decade for calcium ion in the activity range $1x10^{-6}M$ to $1x10^{-2}M$ with and without lipophilic additives. The optimized cation ion-selective membrane electrodes displayed very comparable potentiometric responses to various mono and di-valent cations of alkali and alkaline earth metal ions except $Mg^{2+}$.

• The Journal of Engineering Research
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• v.2 no.1
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• pp.165-174
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• 1997

It is not possible to define the earth's interior because of it complicity. However, it can be interpreted directly and/ or indirectly. Geophysics is the subject of this study. To study the possibility of construction supervision by geophysical method, geophysical prospecting was performed and studied at the SamYang pumping well area in Cheju Island, where, although underground dam was constructed, the saline water invade the pumping well area. This study focuses on the construction supervision by electrical measurements. Two electric resistivity survey lines are installed in the pumping well site, and at each line electric survey was conducted at ebb and flow tides. To increase the data quality SP (self-potential) survey was also performed. As a result the geophysical exploration methods explained the defect of construction well, and It shows that geophysical probe can be a useful tool for the construction supervision.

• Korean Journal of Biological Psychiatry
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• v.8 no.1
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• pp.123-130
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• 2001

Objective : Asymmetries in evoked potential P300 topography of schizophrenia and bipolar disorder are still controversial. The purpose of this study was to examine the difference in P300 topography between schizophrenia and bipolar disorder. Method : P300 was recorded from 16 schizophrenic, 15 bipolar manic, and 16 control subjects. All were right-handed. Subjects silently counted target stimuli(2.0kHz) among trains of standard stimuli(1.0kHz). Averages were constructed from brain responses to target stimuli. Results : 1) Schizophrenics displayed significantly smaller peak amplitude of P300 over Cz, Pz, T3 than controls. 2) Schizophrenics displayed significantly smaller peak amplitude of P300 over T3 than bipolar manics. 3) Schizophrenics displayed significantly smaller peak amplitude of P300 over T3 than their T4. 4) Schizophrenics displayed significantly delayed latency of P300 over T3 than bipolar manics. 5) Schizophrenics displayed significantly delayed latency of P300 over T3 than their T4. Conclusions : Left-sided P300 abnormality, especially left superior temporal gyrus, in schizophrenics relative to bipolar manics and controls suggests that psychophysiological cause of schizophrenia and bipolar disorder is different and P300 asymmetry is specific to the psychophysiological cause of schizophrenia.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05b
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• pp.84-89
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• 1998

Alloy 600 및 alloy 690과 Ni-8Cr-lOFe 합금 등의 응력부식(stress corrosion cracking, SCC) 거동을 고온의 염기성 분위기에서 C-ring 시편을 사용하여 연구하였다. Alloy 600과 alloy 690을 여러 조건에서 열처리하여 etching한 후 탄화물의 분포와 입계 주변의 Cr고갈 정도 등의 미세조직을 광학현미경과 주사 전자현미경(SEM)으로 관찰하였다. 이들 재료에 대한 SCC 시험을 315$^{\circ}C$의 40% NaOH 수용액에서 일정한 부하전위(부식전위 + 200㎷)를 가하면서 수행하였으며, 동일 조건에서의 분극거동도 측정하였다. Alloy 600 MA(mill anneal) 및 TT(thermal treatment)의 SCC 저항성은 alloy 690 TT와 Ni-8Cr-10Fe SA(solution anneal)보다 낮았다. Alloy 600 TT 재료는 alloy 600 MA 및 SA 재료에 비해 SCC 저항성이 더 컸다. 고용 탄소농도는 alloy 600의 SCC 저항성에 큰 영향을 주지 못했다. 대부분의 Alloy 600은 균열전파 입계균열을 보였으나, 일부에서는 입계 및 입내 혼합양상(mixed mode cracking)을 보였다. 염기성 분위기에서 Ni기 합금의 SCC 거동을 미세조직, 분극거동의 관점에서 고찰하였다.

• The Korean Journal of Pharmacology
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• v.20 no.1 s.34
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• pp.23-32
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• 1984

The effects of morphine on the transmembrane potential and the short circuit current in the isolated frog skin were studied under different experimental conditions. The measurem ents of the transmembrane potential and the short circuit current were carried out according to Ussing and Zerahn's method. Experimental results were summerized as follows: 1) $5{\pm}10^{-3}$M of morphine markedly depressed the transmembrane potential and the short circuit current of the naive preparation. The peak of these inhibitory effects of morphine was observed about 1 hour after administration of the drug. 2) However $10^{-4}$M of naloxone did not affect these effects of morphine. 3) Decrease of $K^+$, increase of $K^+$ or $Ca^{2+}$ in the perfusate, markedly potentiated the inhibitory action of morphine on both transmembrane potential and short circuit current of the frog skin, and addition of $Mn^{2+}$ to the solution depressed the effect of morphine on the transmembrane potential, while the inhibitory effect of morphine on the short circuit current was diminished in the $Ca^{2+}$-free ringer solution, and increase of $Mg^{2+}$ concentration depressed those effect of morphine on both electrical parameters. 4) In the morphine treated preparations, transmembrane potential and short circuit current were decreased in the early phase of drug treatment ($1{\sim}2$ days), but gradually increased to the significantly high level from the control (48 days after treatment). In these preparations, the effects of morphine on both electrical parameters were also potentiated in the early phase, but markedly diminished in the late phase of treatment. From the above results, it is postulated that the pharmacological actions of morphine as well as development of the tolerance by morphine may be partially related to the changes of ion fluxes and/or permeabilities of skin by the drug.

• Journal of Veterinary Clinics
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• v.31 no.2
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• pp.129-132
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• 2014

A 4-year-old, intact female Border Collie was presented for evaluation of hearing impairment. Clinical, neurological, otoscopic and magnetic resonance imaging examinations were carried out to determine the cause of hearing loss, but no remarkable change was found. Then, brainstem auditory-evoked response test was performed to assess hearing loss, and the dog had a bilateral sensorineural deafness was revealed. Since possible causes of acquired hearing loss were ruled out by several examinations and history taking, bilateral later-onset deafness was suspected to be genetic and not congenital. This report suggested the possibility that dogs had inherited later-onset sensorineural deafness.

• Sleep Medicine and Psychophysiology
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• v.1 no.1
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• pp.87-98
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• 1994

Objectives: To examine a defect in inhibitory gating of auditory evoked response in schizophrenics, to compare P3 latency and amplitude in negative and positive schizophrenics, and to assess the association of P3 with family history of the psychiatric disorders, electroconvulsive therapy, and clinical features. Methods: 54 schizophrenics(male 31, female 23) and 75 controls(male 33, female 42) were tested with event-related potential paradigm designed to elicit P3 response and Frankfurter Beschwerde Fragebogen. Results: In schizophrenics, the latency of P3 was significantly more delayed and the amplitude of P3 was significantly more reduced than in the controls. Significant differences in P3 latency and amplitude between negative and positive schizophrenics were not found. And significant difference in the P3 latency and amplitude between schizophrenics with family histories of psychiatric disorder and those without family histories of psychiatric disorder was not found also. The P3 latency and amplitude was not significantly related with electroconvulsive therapy and other clinical features such as age, duration of illness, onset of inllness, number of admission, and doses of antipsychotics etc. Conclusion: These results suggested that schizophrenics had a dysfunction in the process of selective attention and that P3 was not significantly related with family history of the psychiatric disorders, positive and negative symptoms, electro1convulsive therapy, and clinical features in schizophrenics.

• Clinics in Shoulder and Elbow
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• v.16 no.2
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• pp.107-114
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• 2013

Purpose: This study is designed to evaluate the clinical and radiographical results for the displacement of fracture fragments after interlocking intramedullary nailing in humeral shaft fractures. Materials and Methods: We retrospectively reviewed the results of 8 cases of humeral shaft fractures that have displacements of over 10 mm and under 20 mm after interlocking intramedullary nailing between July 2004 and August 2011. The mean age was 54.1 years (range, 43 to 70 years) and there were 3 male and 5 female patients. Radiographically, the time to bony union, change of displacement and angulation of the fracture site, and degree of improvement of these two factors were measured. Clinically, the range of motion of shoulder and elbow joints, postoperative pain and complications were evaluated. Results: All cases showed complete bony union in last follow-up. The mean time to bony union was 16.1 weeks. At the last follow-up, almost all cases had normal range of motion of shoulder and elbow joints. But, one case had stiffness of shoulder joint. Therefore, arthroscopic capsular release and manipulation was performed. One case had transient shoulder pain and the other case had transient elbow pain. In the two cases, pull-out of proximal interlocking screw were noted, but they finally had bony union. Conclusion: Although considerable displacement of fracture fragments after interlocking intramedullary nailing in humeral shaft fractures was present, we had excellent radiographical and clinical outcomes. Therefore, an additional procedure, such as open reduction or another fixation for the fracture site, was not necessary.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2008.11a
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• pp.243-244
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• 2008

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.11a
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• pp.72-72
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• 1998

원자력발전소 1차계통내 밸브의 경면처리(hardfa따1잉에 사용되는 재료는 $90~343^{\circ}C$의 고온과 높은 접촉응력 그리고 급격한 압력변화가 일어나는 환경에서 사용되기 때문에 내마모성과 내식성 그리고 cavitation erosion 저항성이 우수한 Co계 Stellite 합금이 현재 사용되어진다. 그러나 Co가 원력발전소 1차계통의 방사선장을 형성하는 주요 원소로 알려지면서 S Stellite 합금을 대체할 수 있는 Fe계 경면처리용 합금을 개발하려는 연구가 진행되고 있다. 현재 Fe계 경면처리용 합금의 개발은 적절환 팝금원소를 첨가하여 적충결함에너지를 낮춤 으로써 전위의 교차슬립을 억제하여 표면을 경화시키고, 소성변형을 억제하여 마모저항성을 향상시키려는 방법으로 연구가 진행되고 있다. 본 연구에서는 Fe-Cr-Ni-Si-C 합금에 Fe계 합금의 적충결함에너지를 감소시키는 것으로 알려진 vanadium을 0, 1, 2wt%첨가하여 첨가량의 변화가 cavitation erosion 저항성에 미치 는 영향을 조사하였다. Cavitation erosion 실험은 초음파를 이용하여 미세한 기포를 발생시키는 vibratory type으로 A ASTM G-32 규격에 따라 제작된 실험장치를 이용하여 $25{\pm}2^{\circ}C$의 온도의 증류수 속에 잠긴 상태에서 실시하였다. 시면은 지름 16mm, 두게 7mm의 버턴형태로 vanadium 첨가량을 변화시킨 조성을 아크 용융 방법을 이용하여 제작하였으며 hom끝단부에 부착하여 cavitation e erosion 저항성 살험을 하였다. 시편의 cavitation erosion 실험시간에 따른 무게감소량을 측 정하였으며 cavitation erosion 시킨 시편의 표면을 SEM으로 관찰하였다.겨지는 열전달 매체액 과 신규 부식억제제가 적용된 시스템 등 객관적으로 확인된 부식억제제 시스랩에 대 하여 다양한 평가 방법을 동원 비교분석하고자 하였다. 실험은 KSM 2142에 의한 무게감량법, 분극곡선 측정에 의한 $E_P$(공식개시전위), $E_R$(재부동태화전위) 측정, 시간에 따른 자연전위 변화 측정 빛 이때의 부식속도(선형분극법), 인위적인 피막 파괴 전,후 의 전위 변화 및 부식속도 측정법에 의한 국부부식 발달 저지능 등을 평가하여 각 실험결과를 비교분석하여 보았다. 수록 민감하여 304 의 IGSCC 와 매우 유사한 거동을 보인다. 본 강연에서는 304 와 600 의 고온 물에서 일어나는 IGSCC 민감도에 미치는 환경, 예민화처리, 합금원소의 영향을 고찰하고 이에 대한 최근의 연구 동향과 방식 방법을 다룬다.다.의 목적과 지식)보다 미학적 경험에 주는 영향이 큰 것으로 나타났으며, 모든 사람들에게 비슷한 미학적 경험을 발생시키는 것 이 밝혀졌다. 다시 말하면 모든 사람들은 그들의 문화적인 국적과 사회적 인 직업의 차이, 목적의 차이, 또한 환경의 의미의 차이에 상관없이 아름다 운 경관(High-beauty landscape)을 주거지나 나들이 장소로서 선호했으며, 아름답다고 평가했다. 반면에, 사람들이 갖고 있는 문화의 차이, 직업의 차 이, 목적의 차이, 그리고 환경의 의미의 차이에 따라 경관의 미학적 평가가 달라진 것으로 나타났다.corner$적 의도에 의한 경관구성의 일면을 확인할수 있지만 엄밀히 생각하여 보면 이러한 예의 경우도 최락의 총체적인 외형은 마찬가지로 $\ulcorner$순응$\lrcorner$의 범위를 벗어나지 않는다. 그렇기 때문에도 $\ulcorner$