• 한국구조물진단유지관리공학회 논문집
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• 제24권1호
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• pp.59-66
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• 2020

본 연구에서는 보수 모르타르와 직접 혼합 가능한 결정성장형 자기치유 고상캡슐을 제조하였으며, 자기치유 고상캡슐이 혼합된 보수 모르타르의 품질 및 균열 치유 성능 특성을 평가하였다. 자기치유 고상캡슐을 혼합한 보수 모르타르의 테이블 플로우 및 공기량 평가 결과 혼합율에 관계없이 테이블 플로우 및 공기량은 큰 영향이 없는 것으로 나타났다. 압축강도는 캡슐 혼합율이 증가할수록 강도가 감소하는 경향이 나타났다. 정수위 투수시험에 따른 균열 치유 특성 평가 결과 초기 투수량이 감소하는 결과가 나타났으며, 시간 경과에 따라 반응 생성물 발생하여 균열이 치유되는 것을 확인 할 수 있었다.

• 대한간호학회지
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• 제20권2호
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• pp.131-141
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• 1990

Recently, the rate of cesarean section in Korea has been increasing. The results of several previous studies in foreign countries on the emotional responses of cesarean section mothers showed that they might experience difficulties in the mother- infant interaction due to fatigue, lack of early mother - infant interaction, disappointments, anger, feelings of loss of control, and other factors. Human behavior is said to be determined by one's self concept, and self concept is influenced by both internal and external environmental factors. A scale to measure the self concept of cesarean section mothers was needed in order to identify those who might have difficulties in the mother- infant interactions in future. The purposes of this study were to develop a measuring scale, and to test its reliability and validity. The process of this study was as follows. A structured interview was done with 50 cesarean section and vaginal delivery mothers to find their state of emotional reaction after giving birth to their babies. Based on the results of the interviews, a 50 items Likert scale was developed. The self concept of 268 cesarean section and vaginal delivery mothers who were hospitalized at six hospital in seoul were measured, during the period between Feb. 1 and April 30. Reviewing the discriminating power of each item by means of crosstabulation, ten items were selected for the final scale. The reliability and validity of this ten item scale were tested by Cronbach's alpha and t-test, using spss pc＋package. The results of this study and recommendation are as follows. 1. The ten selected items were as follows. I feel pains in my breast. (－) I have a good appetite now. (＋) I feel pains in my flank. (－) I feel fine now. (＋) My body seems to have returned to its prepregnant state. (＋) Thinking of the delivery process, I feel sorry. (－) I want to hold my baby in my arms. (＋) I want to keep my own life, even if I became a mother. (－) I want to delegate the care of the baby to my mother / mother in law. (－) I think baby is my alter ego. (＋) 2. The reliability of this scale was tested by Cronbach's alpha, and the coefficient of this scale was .8066. 3. The construct validity of this scale was tested by means of known group methods. The value of self concept for cesarean section mother was significantly lower than for vaginal delivery mothers(t＝-5.51, df＝266, p＝0.007). 4. The criterion validity of this scale was tested indirectly. Though this scale could discriminate the differences in the self concept between cesarean section and vaginal delivery mothers, the five items on the personal self concept scale didn's show any differences between cesarean section and vaginal delivery mothers. Therefore, the study indicates that those who shows lower values in the personal self concept measurement, that is, lower than 12.03 points, could be regaled as “risk mothers” 5. Further studies using this scale to clarify the influencing factors on negative self concept are strongly recommended.

• 감성과학
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• 제6권4호
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• pp.15-23
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• 2003

근래에 들어 질병으로 인하여 의사표현이 곤란한 환자에게 뇌파에 기초한 BCI(Brain Compute, Interface)와 같은 새로운 인터페이스를 제공하고자 하는 연구가 활발히 진행되고 있다. 특정 자극에 대해 유발되는 뇌파의 측정과 분석은 BCI를 위한 뇌파의 패턴과 인터페이스의 설계에 중요한 역할을 한다. 이 연구의 목적은 시청각 자극 인가 후 피험자의 반응시간을 측정하는 시스템을 EEG와 같은 생체 신호 계측 시스템과 연동이 가능한 형태로 개발하는 것이다. 제안된 시스템은 기능적으로 자극신호 발생부, 반응시간 측정부, 유발뇌파 측정부, 동기신호 발생부로 나뉘어진다. 자극신호 발생부는 실험에 이용되는 자극신호를 제작하는 부분으로서 Flash를 사용하여 구현하였다. 반응시간 측정부는 문제에 대한 답 선택 요청시각으로부터 피험자의 반응까지의 시간을 측정하는 부분으로서 마이크로컴퓨터를 이용하여 구현하였다. 유발뇌파 측정부는 시판용 하드웨어와 소프트웨어를 그대로 사용하였다. 동기신호 발생부는 전체 시스템의 동기를 맞추기 위한 신호를 발생하는 부분으로서 문제제시, 답 요구와 동기한 화면상의 명암신호와 이를 검출하는 광센서로 구성하였다. 본 논문에서 제시한 방법에서는, 기존의 유발전위 측정 및 자극시스템에 특정 모듈(반응시간 측정 장치, 동기신호 발생장치)만을 추가하여 실험자의 의도에 맞는 시스템을 설계할 수 있어 유발응답 및 반응시간의 측정을 필요로 하는 연구를 가속화 할 것이 기대된다.

• Composites Research
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• 제16권2호
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• pp.54-61
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• 2003

본 연구에서는 자가치료제가 저장된 마이크로캡슐의 제조공법을 소개하였으며 제조공정변수를 달리하여 제조된 마이크로캡슐의 특성을 입도분석기, 광학현미경, TGA 등을 통해 평가하였다. 이때 자가치료용 마이크로캡슐은 요소-포름알데히드 수지로 구성된 박막으로 되어 있으며 마이크로캡슐의 내부에는 자가치료제인 DCPD가 충전되어 있는 경우를 고려하였다. 마이크로캡슐의 제조공정변수로는 (1) 24시간. 40시간. 48시간, 60시간의 EMA copolymer 용해시간, (2) pH3.5, pH4.0, pH4.5의 수소이온농도, (3) 400rpm, 500rpm, 600rpm. 1000rpm의 교반속도, (4) $50^{\circ}$, $55^{\circ}$, $60^{\circ}$의 반응온도 등을 고려하였다. 연구결과에 따르면 마이크로캡슐의 입도분포는 교반속도에 따라 달라지며, EMA copolymer의 용해시간, 수용액에서의 수소이온농도 및 반응온도 등은 마이크로캡슐의 열안정성에 큰 영향을 미친다. 따라서 마이크로캡슐의 내부에 저장된 자가치료제의 증발을 억제할 수 있는 우수한 열안정성을 갖는 마이크로캡슐을 제조하기 위해서는 적절한 제조공정변수가 적용되어야 한다.

• 한국심리학회지 : 문화 및 사회문제
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• 제10권3호
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• pp.83-101
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• 2004

본 연구는 사이버 공간에서 자기 자신과 타인의 실재(實在)에 대한 지각을 높이는 방편으로써 사회적실재감((社會的 實在感)이 사이버 공격행동을 감소시킬 수 있는지 알아보고자 하였다. 이를 위해 온라인 게임 "포트리스2 blue forever"에 실험자가 미리 게임방을 개설하고, 실험사실을 알지 못한 채 입장한 피험자 107명을 대상으로 현장실험을 실시하였다. 피험자는 미리 대기하고 있던 3명의 실험자들과 게임시작 전에 이루어지는 채팅을 통하여 사회적 실재감 수준을 조절한 '통제집단', '실험집단1', '실험집단2' 의 세 집단에 각기 할당되었다. 이후 게임 중 피험자의 언어적 공격행동과 캐릭터를 이용한 공격행동의 빈도를 관찰한 결과, 통제집단의 피험자들은 실험집단의 피험자들보다 유의하게 더 많은 언어적 공격행동과 캐릭터 공격행동을 보였다. 한편, 사회적 실재감의 획득 경로에 따른 차이를 알아보기 위해 실험집단1과 2를 비교한 결과 피험자의 말과 행동에 대한 반응만을 처치한 집단1의 피험자는 자기노출을 추가 처치한 실험집단2의 피험자보다 언어적 공격행동을 유의하게 더 많이 한 반면, 캐릭터 직접 공격행동에서는 두 집단 간 차이를 보이지 않았다. 본 연구는 실명제나 처벌을 강제하지 않고 사이버 공격행동을 줄일 수 있는 가능성을 제시하고, 사회적 실재감과 사이버 공격행동의 관계를 밝혔다는 의의가 있다.

• 한국분말재료학회지
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• 제6권3호
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• pp.215-223
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• 1999

The synthesis of $Ni_5Si_2,\;Ni_2Si$ and NiSi has been investigated by mechanical alloying (MA) of Ni-27.9at%Si, Ni-33.3at%Si and Ni-50.0at%Si powder mixtures. As-received and premilled elemental powders were subjected to MA. The as-received Ni powder was spherical and the mean particle size 48.8$\mu$m, whereas the premilled Ni powder was flaky and the mean particle diameter and thickness were found to be 125 and 5$\mu$m, respectively. The mean surface area of the premilled Mi powder particle was 3.5 times as large as that of the as-received Ni powder particle. The as-received Si powder was was 10.0$\mu$m. Self-propagating high-temperature synthesis (SHS) reaction, followed by a slow reaction (a solid state diffusion), was observed to produce each Ni silicide during MA of the as-received elemental powders. In other word , the reactants and product coexisted for a long period of MA of time. Only SHS reaction was, however, observed to produce each Ni silicide during MA of the premilled elemental powders, indicating that each Ni sillicide formed rather abruptly at a short period of MA time. The mechanisms and reaction rates for the formation of the Ni silicides appeared to be influenced by the elemental powder particle size and shape as well as the heat of formation of the products $(Ni_5Si_2$longrightarrow-43.1kJ/mol.at., $Ni_2Si$$\rightarrow$-47.6kJ/mol.at.).

• 혜화의학회지
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• 제15권2호
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• pp.263-272
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• 2006

Purpose Brain vessles have autoregulation function, so even when perfusion pressure drops, cerebral blood flow remain stable by vasodilation. Latest research on this reserve of cerebral vessels is being done using TCD, which measures the reserve of the vessels. We did a research comparing cerebral vessel and peripheral vessel reserve between Taeumin, who are more likely to suffer CVA, and the normal. We observed blood flow of Internal carotid artery siphon and radial indicis artery of the two group with TCD. Method We picked 20 people out of patients diagnosed as cerebral infarction at Cheon-An Oriental hospital of Daejeon University. They were diagnosed as Taeumin with QSCCII questionnaire and constitutional differentiation. Using TCD, we measured highest blood flow rate, mean blood flow and asymmetric counting blood flow of Internal carotid artery siphon and radial indicis artery at rest. And then we measured again after stimulating cerebral vessels, by triggering hypercapnia by self apnea and peripheral vessels by palm heating. Result At rest, mean blood flow rate of Internal carotid artery siphon showed significant decrease compared to control group. Blood flow rate of Internal carotid artery siphon after hypercapnia showed significant decline in highest blood flow rate and mean blood flow compared to control group. Cerebral vessel reaction after the hypercapnia induction showed great change in experiment group than the control group. Peripheral vessel reaction after palm heating showed significant decline in experiment group compared to control group. Conclusion In conclusion, measuring the alteration of blood flow used in diagnosing cerebral infarction, is more sensitive when vessel stimulation is done. Non-invasive TCD is effective especially in case of Taeumin who are more likely to suffer vascular disorder than others.

• 한국세라믹학회지
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• 제47권5호
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• pp.381-386
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• 2010

Some basic properties of inorganic coatings hardened by the room temperature reaction with alkalies were examined. The coating paste was prepared from the powders in the system $Al_2O_3-SiO_2$-CaO using blast furnace slag, fly ash and amorphous ceramic fiber after mixing with a solution of sodium hydroxide and water glass. The mineralogical and morphological examinations were performed for the coatings prepared at room temperature and after heating to $1200^{\circ}C$ respectively. The binding force of the coating hardened at room temperature was caused by the formation of fairly dense matrix mainly composed of oyelite-containing amorphous phase formed by the reaction between blast furnace slag and alkali solution. At the temperature, fly ash and ceramic fiber was not reacted but imbedded in the binding phase, giving the fluidity to the paste and reinforcing the coating respectively. During heating up to $1200^{\circ}C$, instead of a break in the coating, anorthite and gehlenite was crystallized out by the reaction among the binding phase and unreacted components in ternary system. The crystallization of these minerals revealed to be a reason that the coating maintains dense morphology after heating. The maintenance of binding force after heat treatment is seemed to be also caused by the formation of welldispersed fiber-like mineral phase which is originated from the shape of the amorphous ceramic fiber used as a raw materials.

• 폴리머
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• 제35권4호
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• pp.302-307
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• 2011

실란 커플링제의 가수분해를 통한 실란올의 형성과 올리고머 구조형성을 하는 중합반응은 2-FCCL의 표면처리 과정에서 계면 사이의 접착력에 영향을 준다. 본 연구에서는 설란 커플링제의 가수분해반응 속도를 비교하고 표면처리 후 동박의 표면 에너지로 인한 접착특정의 변화를 확인하였다. 특히 이성분계 살란 커플링제는 가수분해 반응속도 조절이 기능하며, 동박과 폴리이미드 사이에서 접착 프로모터로서 확실한 접착력 향상을 보였다. 압연동박 표면에 처리한 이성분계 실란 커플링제의 함량 변화에 띠라 접착력의 향상 정도가 다르게 나타났으며 반응속도 조절과 표면 에너지 평가를 통한 접착 특성을 분석해 접착력을 최대화시켰다.

• Bulletin of the Korean Chemical Society
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• 제15권10호
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• pp.857-860
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• 1994

We have calculated the ${\pi}$-electron density, atom self-polarizability, and free valence on each atom of N-(2-chlorobenzyl)-pyridinium, N-(benzyl)-2-chloropyridinium, and N-(2-chlorobenzyl)-2-chloropyridinium salts using a simple Huckel method in order to discuss their intramolecular photocyclization reaction in a qualitative method. Our calculation qualitatively predicts that photocyclization occurs through forming radicals as a reaction intermediate by breaking a C-Cl bond after photoexcitation into a triplet state via intersystem crossing from an initially excited singlet state. We noticed that this C-Cl bond breaking is aided by ${\pi}$-complex formation between a chlorine atom and the ${\pi}$ -electrons of the neighboring ring in the triplet state and a stronger ${\pi}$-complex bond makes C-Cl bond breaking, i.e., radical formation, much easier. A chlorine atom will form a stronger ${\pi}$ -complex bond to a benzyl ring of N-(benzyl)-2-chloropyridinium than a pyridinium ring of N-(2-chlorobenzyl)-pyridinium because the former can donate its ${\pi}$-electron more easily than the latter. The chlorine at position 15 of N-(2-chlorobenzyl)-2-chloropyridinium salt in the excited state also provides its ${\pi}$-electron to the benzyl ring. So this ${\pi}$-electron can increase the bond strength of the $\pi-complex.$ Therefore, the strength of ${\pi}$-complex follows the order of N-(2-chlorobenzyl)-2-chloropyridinium, N-(benzyl)-2-chloropyridinium, and N-(2-chlorobenzyl)-pyridinium salts and thus the radical formation rate. This provides us with an intramolecular photocyclization reaction rate of the same order as given above.