Phosphors for Plasma Display Panels

김창홍,배현숙,변종홍,홍광옌,Kim, Chang Hong,Bae, Hyun Sook,Pyun, Chong Hong,Hong, Guang Yan Korean Chemical Society 1998 대한화학회지 Vol.42 No.5

플라스마 표시판용으로 사용되거나 제안 또는 알려진 형광체들의 들뜸 및 발광 특성을 살펴 보았다. 각 형광체의 발광 효율이 임자 결정과 활성제의 종류에 따라 어떻게 달라지는지 알아 보았고 실용성 있는 형광체의 개발 방향을 생각하였다. Excitation and emission characteristics were reviewed for phosphors which were reported, applied, or suggested for the plasma display panel (PDP). Correlation of luminescence characteristics to the host crystal structure and the activator of the phosphor was explained. Improvements of the PDP phosphor for the practicality were considered.

난소종양의 임상 및 조직병리학적 고찰

김창홍,김흥곤,문형배 圓光大學校 醫科學硏究所 1992 圓光醫科學 Vol.8 No.1-2

This study was undertaken for the clinical evaluation and statistical analysis on the 301 patients with ovarian tumors who were operated and confirmed by histopathological study at the Dept. of Obstetrics and Gyneclogy, Wonkwang University Hospital from Jan. 1, 1986 to Dec. 31. 1991. The results obtained were as follows. 1. Among 301 cases, 91 cases (30.2%) were non-neoplastic, 199 cases (66.1%) were benign neoplastic tumors and 11 cases (3.7%) were malignant tumors. 2. Simple cyst was most frequent among non-neoplastic tumor. Among benign ovarian tumors, 49.8% were cystic teratoma ranked first followed by serous cystadenoma and mucinous cystadenoma comprising 25.1% and 23.1% respectively in order of frequency. 3. On histopathological classification, the tumor originated from common epithelial cell was 49.5%, germ cell tumor was 49.0% and remainds were gonadal stromal origin. 4. Non-neoplastic and benign neoplastic ovarian tumors were most prevalent in twentieth and thirtieth, but malignant neoplastic tumor were most prevalent in fortieth. 5. On the parity of patients with benign neoplastic tumors, nulliparities were most common (27.6%). On that of malignant tumor, multiparities were most common (72.7%). 6. Menstrual pattern was regular in 71.1%, irregular in 11.3% and physiologic amenor-rhea in 17.6%. 7. As to the subjective symptoms of the ovarian tumors, lower abdominal pain and discomfort was 55.5% ranked first followed by palpable mass 18.7%, lumbago 7.0% and abnormal vaginal bleeding 6.0% in sequence. 8. The mean size of non-neoplastic tumors, benign & malignant ovarian tumors were 7.4 ㎝, 11.7 ㎝ and 12.0 ㎝ in diameter respectively. 9. Bilaterality was noticed in 4.4% of non-neoplastic tumors, 7.1% of benign ovarian tumors and 27.2% of malignant one. 10. The ovarian tumors associated with pregnancy were 45 cases (15.0 %). Among them, 23 cases were intrauterine pregnancy and 22 cases were ectopic pregnancy. 11. Among 45 cases (15.0%) of complications, 27 cases (60.0%) were torsion and 18 cases (40.0%) were rupture.

Molecular Theory of Plastic Deformation (I). Theory

김창홍,이태규,Kim Chang Hong,Ree Taikyue Korean Chemical Society 1977 대한화학회지 Vol.21 No.5

In order to elucidate the plastic deformation of solids, the following assumptions were made: (1) the plastic deformation of solids is classified into two main types, the one which is caused by dislocation movement and the other caused by grain boundary movement, each movement being restricted on a different shear surface, (2) the dislocation movement is expressed by a mechanical model of a parallel connection of various kinds of Maxwell dislocation flow units whereas the grain boundary movement is also expressed by a parallel connection of various kinds of Maxwell grain boundary flow units; the parallel connection in each type of movements indicates that all the flow units on each shear surface flow with the same shear rate, (3) the latter model for grain boundary movement is connected in series to the former for dislocation movement, this means physically that the applied stress distributes homogeneously in the flow system while the total strain rate distributes heterogeneously on the two types of shear planes (dislocation or grain boundary shear plane), (4) the movement of dislocation flow units and grain boundary units becomes possible when the atoms or molecules near the obstacles, which hinder the movement of flow units, diffuse away from the obstacles.Using the above assumptions in conjunction with the theory of rate processes, generalized equations of shear stress and shear rate for plastic deformation were derived. In this paper, four cases important in practice were considered.ted N${\cdot}{\cdot}{\cdot}$O hydrogen bond and the second of two normal N${\cdot}{\cdot}{\cdot}$O hydrogen bonds, both of which exist between the amino group and the perchlorate, groups. A p-phenylenediamine group is approximately planar within an experimental error and bonded to twelve perchlorates: ten perchlorates forming hydrogen bonds and two being contacted with the van der Waals forces. A perchlorate group is surrounded by six p-phenylenediamines and four perchlorates; among the six p-phenylenediamines, five of them are hydrogen-bonded, and the rest contacted with the van der Waals force. 고체의 소성변형을 설명하기 위하여 다음과 같은 가정을 하였다. (1) 고체의 소성변형은 크게 두 가지 기구 즉 dislocation 운동과 grain boundary 운동에 의하여 일어난다. (2) Dislocation 운동에 있어서 유동 단위들은 역학적 모형으로 나타내면 다종의 Maxwell 단위들의 평행연결형으로 되고 grain boundary 유동단위들도 다종의 Maxwell 단위들의 평행연결로 표현된다. 이를 물리적으로 설명하면 같은 부류의 유동단위들은 모두 같은 shear plane에서 같은 shear rate로 흐름을 의미한다. (3) Grain boundary 유동단위들과 dislocation 유동단위들 같은 서로 직렬 연결되어 있다. 이는 물리적으로 고체내에서 stress는 균일하게 작용하나 shear rate는 shear plane 의 종류(dislocation 운동면과 grain boundary 운동면)에 따라 달리 나타남을 의미한다. (4) Dislocation 유동단위들과 grain boundary 운동단위들의 운동은 그들의 흐름을 방해하는 장애물 근방의 원자 또는 분자들이 확산해 나가므로써 가능하게 된다. 이러한 가정하에 반응속도론을 적용하여 shear rate와 shear stress를 구하는 일반식을 도출하였다. 본 연구에서는 실제로 중요한 네가지 경우에 대하여 상기 도출한 일반식을 고찰하였다.

자궁외 임신의 임상적 고찰

김창홍,박성찬,김흥곤 圓光大學校 醫科學硏究所 1991 圓光醫科學 Vol.7 No.1-2

The incidence of ectopic pregnancy is apparently increasing in recent years. This study was undertaken for the clinical evaluation & statistical analysis on the 215 patients with ectopic pregnancy who were operated & confirmed by histopathological study at the Dept. of Obstetrics & Gynecology, Wonkwang University from Jan. 1, 1986 to Dec. 31, 1990. The results obtained were as follows. 1. The incidence of ectopic pregnancy was 1 in 25 deliveries (215/5375). 2. Ectopic pregnancy was found to occur most frequently in the age group, ranging from 26 to 30 years (40.5%). 3. Most frequent number of delivery & pregnancy was one times (30.7%) & two times (22.3%) respectively. 4. Most frequent number of artificial abortion was one times (32.4%) & nulligravida was 9.3%. 5. In the past history, 63.3% of the patients had previous artificial abortion, 17.7% had laparoscopic tubal sterilization & 6.6% had previous ectopic pregnancy. 6. The duration from LMP to onset of symptoms was 6~9 weeks (74.0%) most frequently. 7. According to symptomatological analysis, lower abdominal pain (94.4%), vaginal bleeding or spotting (55.3%), amenorrhea (86.1%) were the most common presenting signs & symptoms. 8. Urine hCG test was positive in 72.1% & culdocentesis was positive in 92.0%. 9. Ectopic pregnancy was implanted on the fallopian tube in 94.9 %. 10. The amount of intraabdominal hemorrhage was below 500 ㎖ in 40.9%, 500 ∼ 1,000 ㎖ in 24.2% & over 2,000 ㎖ in 7.9%. 11. Most commonly used surgical procedure was unilateral salpingectomy (50.7%). 12. There was no maternal death.

Molecular Theory of Plastic Deformation (II). Applications

김창홍,이태규,Kim, Chang Hong,Ree Taikyue Korean Chemical Society 1977 대한화학회지 Vol.21 No.5

소성변형에 대한 저자들의 이론(제1보)을 요업재료, 금속, 합금 및 단결정들에 적용하였다. 그 결과 다중 결정에서는 dislocation 운동과 grain boundary 운동이 실험조건에 따라 함께 또는 분리되어 나타나는 반면 단결정에서는 dislocation 운동만 나타났다. 유동식에 나타나는 파라미터$({\alpha}_{d1},\;1/{\beta}_{d1})와\;({\alpha}_{gj}/X_{gj},\;1/{\beta}_{gj})$ (j = 1 or 2) 및 활성화엔탈피 ${\Delta}H_{k1}^{\neq}$ (k = d 혹은 g)를 구하여 예측한 소성변형은 실험과 잘 일치함을 보았다. 여기서 첨자 d1는 첫번째의 dislocation 유동단위, gj는 j번째 grain boundary 유동단위를 나타낸다. 활성화엔탈피에 대하여 ${\Delta}H_{d1}^{\neq}$는 bulk의 자체확산에 대한 활성화엔탈피와 일치하고 ${\Delta}H_{g1}^{\neq}$는 grain boundary 자체확산에 대한 활성화엔탈피와 일치하였다. 이 사실은 저자들의 이론의 정당성을 보이고 있다. The authors' theory developed in the preceding Paper 1 was applied to plastic deformation of ceramics, metals, alloys and single crystals. For polycrystalline substances, the flow mechanisms due to dislocation movement and grain boundary movement appear together or separately according to the experimental conditions whereas for single crystals, only the mechanism of dislocation movement appears. The parameters appearing in the flow equations $({\alpha}_{d1},\;1/{\beta}_{d1})and\;({\alpha}_{gj}/X_{gj},\;1/{\beta}_{gj})$ (j = 1 or 2), and the activation enthalpies ${\Delta}H_{k1}^{\neq}$ (k = d or g) were determined and tabulated. Here, the subscript d1 indicates the first kind of dislocation flow units and gj expresses the jth kind of grain boundary flow units. The predictions of the theory were compared with experiment with good agreement. Concerning the activation enthalpies, it was found that ${\Delta}H_{d1}^{\neq}$ 〉{\Delta}H_{g1}^{\neq}$ and that the former agrees with the activation enthalpy for bulk self-diffusion whereas the latter agrees with the activation enthalpy for grain boundary self-diffusion. These facts support the adequacy of the authors' theory which is considered as a generalized theory of plastic deformation.

난소 내배엽동 종양에서 BEP 복합화학요법에 의한 완전관해 1 예

김창홍,김홍곤,윤기중,권상철,이승준,이찬근,황성연 대한산부인과학회 1997 Obstetrics & Gynecology Science Vol.40 No.11

Endodermal sinus tumors(EST) have also been referred to as $quot;yolk sac tumors$quot; because they are derived from the primitive yolk sac. These lesions are the third most frequent malignant germ-cell tumors of the ovary. Recent advances in treating the endodermal sinus tumor of the ovary with the combination chemotherapy result in improvement of the prognosis. We had experienced a case of the endodermal sinus tumor of 15 year old woman. We report this case with a brief review of literatures.

Molecular Theory of Superplastic Deformation

김창홍,이태규,Chang Hong Kim,Taikyue Lee Korean Chemical Society 1979 대한화학회지 Vol.23 No.4

소성변형에 대한 著者들의 이론을 초소성합금(Zn-Al eutectoid, A1-Cu, Pb-Sn, Sn-Bi, Mg-Al eutectics)에 적용하였다. 그 결과 초소성합금의 소성변형은 두 개의 grain boundary流動單位의 平行連結로 나타낼 수 있었다. 이 두 개의 流動單位는 流動式에 나타나는 parameter $X_{gj}/{\alpha}_{gj}$와 ${\beta}_{gj}$(j=1 혹온 2)로 表現할 수 있으며 이들을 實驗的으로 求할 수 있었다. 著者들의 流動式은 實驗과 잘 一致하였다. Strain rate sensitivity 對 -In(strain rate) 곡선을 이론으로 구한 결과 유동단위수만큼의 peak가 ${\beta}_{gj}$(j=1 or 2) 값에 따라 분리되어 나타났고 초소성의 조건도 ${beta}_{gj}$값에 의하여 결정됨을 알았다. ${\beta}_{gj}값의 粒子크기 依存性을 구하였고 온도변화에 따른 ${\beta}_{gj}$값 변화로부터 각 流動單位의 활성화엔탈피, ${\Delta}H_{gj}^{\neq}$도 구하였다. 그 결과 ${\Delta}H_{gj}^{\neq}$는 재료성분원소들의 grain boundary 자체확산에 의한 활성화엔탈피와 같이 나타났고 또 이들은 粒子 크기 증가에 마라 증가함을 보였다 The author's theory for plastic deformation was applied to superplastic alloys (Zn-Al eutectoid, Al-Cu, Pb-Sn, Sn-Bi, Mg-Al eutectics). The plastic deformation of the superplastic alloys could be described by two Maxwell models connected in parallel which represent two grain boundary flow units. The flow units are characterized by the two parameters $X_{gj}/{\alpha}_{gj}\;and\;{\beta}_{gj}$ (j=l or 2, g signifies the grain boundary) the values of which were obtained by applying our flow equation [Eq. (5)] to experiment. We confirmed that our flow equation describes the superplasticity very well. The curve of strain rate sensitivity m (=${\partial}\;In\;f/{\partial}\;In\;\dot{s})\;vs.\;-In\dot{s}$, where f and s are stress and strain rate, respectively, showed two peaks corresponding to flow unit gl and g2, the separation of the two peaks is determined by the difference between ${\beta}_{g1}\;and\;{\beta}_{g2}$. The condition of superplasticity is also determined by ${\beta}_{gj}$, which satisfies $\dot{s}_{mj}{\leqslant}1.53}{\beta}_{gj}$ [Eq.(13)], where $\dot{s}_{mj}$ is the s of the jth unit at the peak. The grain size dependence of ${\beta}_{gj}$ is described by $ln({\beta}_{gj})^{-1}$=alnx+b [Eq. (16)], where x is the grain size, and a and b are constants. The activation enthalpy for each flow unit, ${\Delta}H_{gj}^{\neq}$ was also determined from the temperature dependence of ${\beta}_{gj}$ which is proportional to the relaxation time of the j th unit. Since the superplasticity is determined by Eq. (13), and since ${\beta}_{gj}$ and ${\Delta}H_{gj}^{\neq}$ are related, we obtained the conclusion that superplasticity occurs in the system having small ${\Delta}H_{gj}^{\neq}$ values. The Aej values were equal to the activation enthalpies of grain boundary self-diffusion of the component atoms of the alloys, this accords with our proposed flow mechanism. The ${\Delta}H_{gj}^{\neq}$ value increases with grain size as expected from Eq. (16).

3D프린팅 기술을 이용한 타원셀 허니컴 제조 및 기계적 특성평가

김창홍(C. H. Kim),김상우(S. W. Kim) 한국생산제조학회 2017 한국생산제조시스템학회 학술발표대회 논문집 Vol.2017 No.12

위암에서 맥관형성 정도와 vascular endothelial growth factor(VEGF) 발현에 관한 연구

박찬국,김창홍,최호열 의과학연구소 1998 全北醫大論文集 Vol.22 No.2

복식 전자궁적출술에 관한 임상적 고찰

황성연,김창홍,김홍곤 圓光大學校 醫科學硏究所 1997 圓光醫科學 Vol.13 No.1-2

Hysterectomy is one of the most common surgical procedures performed; after cesarean delivery, it is the second most frequently performed major surgical procedure in the U.S. This study was attempted to analysis 440 consecutive abdominal hysterectomies, especially concerned with its indication and complication, from January 1, 1995 to December 31, 1996 at the department of Obstetrics and Gynecology, Wonkwang University hospital. The results were summarized as follows: 1. The most common age distribution was 40 to 49 years with 41.4 years of mean age. 2. There couldn't be found any relationship between the indication of surgery and the parity. 3. The most common symptom and sign was lower abdominal pain(52.0 %) and followed by hypermenorrhea(31.3 %) and palpable mass(18.4 %). 4. 29.8 % of all cases was anemic in preoperative check of hemoglobin level, and in 14.3 % of all cases, correction of level was necessary. 5. The uterine myoma was most commonly indicated for Total abdominal hysterectomy (66.8 %) and cervical carcinoma was 7.7 % of all cases. 6. Majority of cases were received abdominal hysterectomies, including 25 cases of radical hysterectomies with pelvic lymphadenectomy. 7. Leiomyoma was the most common postoperative pathologic findings(69.1 %) and followed by adenomyosis(58.4 %). 8. Overall complication rate of abdominal hysterectomy was 21.5 %, which included febrile morbidity of 15.5 %, anemia of 14.1 % and upper respiratory tract infection of 6.1 %.