Experimental investigation of macroscopic material nonlinear behavior and microscopic void volume fraction change for porous materials under uniaxial compression

Lee, Eun Sun,Goh, Tae Sik,Lee, Jung Sub,Heo, Jin-Young,Kim, Gi-Baek,Lee, Chi-Seung Elsevier 2019 Composites Part B, Engineering Vol.163 No.-

<P><B>Abstract</B></P> <P>The purpose of this study was to simultaneously analyze the nonlinear behavior and the void volume fraction change of polyurethane foam (PUF) under a uniaxial compressive load through micro-scale and macro-scale viewpoints. The influence of micro-scale factors on the macroscopic properties of PUF was analyzed, along with the interrelationships between micro-scale and macroscopic properties. The microstructure of PUF was observed by analyzing the density. Various micro-analyses were also conducted, including those for energy absorption, Young's modulus, and recovery behaviors. Internal structure changes such as those in density and degree of compressive strain were analyzed by measuring the void volume fraction of each region in the specimen under a uniaxial compressive load. The elastic, plateau, densification, and fracture regions of the compressive test stress-strain curve were divided, analyzed, and compared with microscopic analysis results. Based on the results of the macro-micro-scale experiment, we analyzed influence and change process of microstructures on the compressive behavior of the PUF specimen in detail. This study shows that internal and overall changes in the compression process of various porous materials can be predicted under a uniaxial compressive load.</P>

In situ 고상 에피택시 방법에 의한 CoSi₂/Si(111)구조의 형성

이정주,강민성,김현수,최치규,이운환,이종덕,이영백,김건호,이정용 濟州大學校 基礎科學硏究所 1996 基礎科學硏究 Vol.9 No.2

초고진공에서 공상에피택시(solid-phase epiyaxy, SPE) 방법으로 CoSi₂를 Si(111)기판 위에 에피택시 성장시켰다. 2MeV⁴He++ ion후방산란 분광기와 사중결정 x-선 회절기 및 고분해 투과전자 현미경을 이용하여 성장된 CoSi₂의 상과 조성, 결정성, 그리고 계면의 미시구조를 조사하였다. 초고진공상태의 실온에서 Si(111)-7X7기판에 Co를 약 20 ~50 ?? 중착한 후 SPE에 의하여 실리사이드를 형성시키는 경우 600℃에서는 B-형의 CoSi₂가, 그리고 700℃에서는 A형의 CoSi₂가 선택적으로 에피택시 성장하였으며, 정합성은 B-CoSi₂[110]//Si[110] and CoSi₂(111)//Si(111)이, 그리고 700℃에서는 A-CoSi₂[110]//Si[110], CoSi₂(002)//Si(002)을 나타내었다. Epitaxial films of CoSi₂were grown on Si(111) substrates by in situ solid-phase epitaxy in a ultrahigh vacuum. The phase, the chemical composition, the crystallinity, and the microstructure of the Silicide/Si interface were investigated by 2-MeV⁴He++ ion-backscattering spectrometry, quadruple crystal X-ray diffractometry, and high-resolution transmission eletron micorscopy. High-quality films of either B-type or A-type CoSi₂ could be grown selectively on Si(111) substrates by depositing ~ 20 ~ 50 ?? of Co on a Si(111)-7X7 substrate followed by in situ annealing at 600℃ or 700℃ for 10 min. The matching face relationships are CoSi₂[110]//Si[110] and CoSi₂(111)//Si(111) by B-type CoSi₂ and CoSi₂[110]//Si[110]//Si[110] and CoSi₂(002)//Si(002) for A-type CoSi₂.

원형 미소 채널 내 드라이 플러그류의 유동 영역 한계와 압력 강하에 관한 실험적 연구

이치영(Chi Young Lee),이상용(Sang Yong Lee) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.11

In the present experimental study, the regime limit and pressure drop of dry-plug flow (dry wall condition at the gas portions of plug flow) in round mini-channels has been investigated. The air-water mixture was flowed through the round mini-channels made of Teflon, where the tube diameters ranged from 1.26 to 2.06 ㎜. For the present experimental range, with decreasing of the tube diameter, the transition between the plug and slug flows (wet and dry) happened at the higher gas superficial velocity region, which were in good agreement with the previous flow pattern maps tested. On the other hand, the transition between the wet- and dry-plug flows was little affected by the change of the tube diameter. In the pressure drop of dry-plug flows, among the correlations tested, the Lee and Lee’s (2008) correlation best fitted the measured pressure drop data within the mean deviation of 10 % for the present experimental range.

악하선 암의 치료성적과 예후인자

임치영(Chi Young Lim),남기현(Kee Hyun Nam),이잔디(Jan Dee Lee),장항석(Hang Seok Chang),정웅윤(Woong Youn Chung),차인호(In Ho Cha),이창걸(Chang Geol Lee),최은창(Eun Chan Choi),박정수(Cheong Soo Park) 대한두경부종양학회 2005 대한두경부 종양학회지 Vol.21 No.2

Purpose: Submandibular gland tumor is rare, less than 6% of head and neck tumor. The purpose of this article is to analysis the clinical experience and treatment outcomes of malignant submandibular gland tumor, suggesting a guideline of management. Methods: We retrospectively evaluated 26 patients who underwent operation for malignant submandibular gland tumor at Severence hospital between 1986 and 2004. Statistical analysis was performed by Kaplan-Meier method, log rank test, Chi-square test, Fisher's exact test using SPSS v12.0 for Windows. Results: They consisted of 18 males and 8 females whose median age was 47 years(range: 20-71). 10 cases of adenocystic carcinoma, 8 cases of carcinoma ex pleomorphic adenoma, 4 cases of mucoepidermoid carcinoma, 1 case each for acinic cell carcinoma, undifferentiated carcinoma, adeno carcinoma, epithelioid hemangioendothelioma. Sialoadenectomy only was performed in 10 cases(36.5%) and sialoadenectomy with neck node dissection was performed in 16 cases(63.5%). Adjuvant radiotherapy was done in 22 cases(84.6%). 10 year disease free survival rate for malignant submandibular gland tumor was 63.1 % and 10 year overall survival rate for malignant submandibular gland tumor was 70.1%. In univariate analysis, prognostic factors affecting recurrence of malignant submandibular gland tumor was initially papable lateral neck node in physical examination and metastasis of lateral neck node in pathologic confirmation. The prognostic factors affecting survival of malignant submandibular gland tumor was tumor size, TNM stage, recurrence and type of recurrence. Conclusion: In this study, prognostic factors affecting recurrence of malignant submandibular gland tumor was initially papable lateral neck node in physical examination and metastasis of lateral neck node in pathologic confirmation. The prognostic factors affecting survival of malignant submandibular gland tumor was tumor size, TNM stage, recurrence and type of recurrence. To prevent recurrence and to improve survival, early diagnosis and aggressive surgery must be considered.

우리나라 시 · 군 · 구 지역보건의료계획의 비전(Vision) 문구 분석

안치영(Chi-Young Ahn),김현수(Hyun-Soo Kim),김원빈(Won-bin Kim),오창훈(Chang-hoon Oh),홍지영(Jee-Young Hong),김은영(Eun-Young Kim),이무식(Moo-Sik Lee) 한국농촌의학 지역보건학회 2017 농촌의학·지역보건 Vol.42 No.1

지역보건의료계획서에서 비전은 각 지역의 보건의료계획을 나타내는 핵심요소임에도 불구하고 작성방법에 대한 구체적인 지침이 부재하여 각 지역의 비전은 매우 다양하게 표현되어 있다. 이에 이 연구에서는 제6기 지역보건의료계획에서 제시한 비전 문구를 보건소 유형별, 권역별로 분석하였다. 전국 229개 지역의 제6기 지역보건의료계획서의 비전 문구와 이와 관련된 미션, 전략체계도, 중장기 추진과제 등을 대상으로 하였다. 지역을 권역별 4개, 읍·면·동 구성에 따른 보건소 유형을 4개로 분류하였고, 각 지역 비전의 글자 수, 문장 평가, 단어 빈도, 문구 평가를 빈도분석과 카이제곱검정, 일원배치분산분석을 이용하여 분석하였다. 비전의 글자 수가 17자 이하인 보건소가 172개소(75.1%)였고, 보건소 유형별로 유의한 차이가 있었다(p<0.05). 문구에 대한 수사표현에서 비유법(37.1%)이, 한글 외에 표현 언어 사용에서는 특수문자(43.2%)가 많았으며, 보건소 유형별로 유의한 차이가 있었다(p<0.01). 비전에 사용된 단어들은 ‘건강’, ‘행복’, ‘함께’, ‘군민’ 또는 ‘시민’, ‘도시’, ‘100세’ 등이었다. 문구평가 점수에서는 특·광역시 및 수도권에서 가장 높았으며, 보건소 유형 및 권역별로 유의한 차이를 보였다(p<0.05). 보건소 유형별로 과정 및 평가 영역, 공유가능성 등에서 유의한 차이가 있었다(p<0.01). 방향성은 충청권, 수도권 순으로 권역별로 유의한 차이가 있었으며(p<0.01), 미래지향성 및 공유가능성은 영남권이 가장 높아 권역별로 유의한 차이가 있었다(p<0.01). 비전은 지역보건의료계획에 가장 중요 요소 중 하나이다. 이 연구는 지역사회 특성별로 비전의 설정이 다름을 확인하였으며, 이러한 결과를 통하여 지역보건의료계획 등 보건소 비전 수립시 참고가 될 수 있는 기초적인 자료가 될 것으로 판단된다. Objectives: In this study, we analyzed vision statements of the 6th community health plan of local government in Korea. Methods: We examined vision statements letters, missions and strategy plans, and long-term missions of 6th community health plans of 229 local government in Korea. We also analyzed the numbers of vision letters, sentence examination, word frequency, each vision statement with frequency analysis, chi-square test, and one-way ANOVA. Results: Among 229 local government, 172(75.1%) of local government had the number of letters (Korean) less than 17 of vision statements, and there were a significant differences according to type of community health centers (p<0.05). Figuration (37.1%) were the most used in an expression of vision statement sentence, and special characters (43.2%) were the most used language except Korean. The most commonly used words of vision statement in order of frequency were ‘health’, ‘happiness’, ‘with’, ‘citizen’, ‘city’, ‘100 years old’ etc. Chungcheong provinces and Daejeon metropolitan city had a highest score in directionality on phrase evaluation, and there were a significant differences according to regional classes of local government (p<0.01). Gyeongsang provinces, Ulsan, Daegu, and Busan metropolitan cities had a highest score in future orientation and sharing possibilities on phrase evaluation, and there were a significant differences according to regional classes of local government (p<0.01). Conclusions: Vision is one of the most important component of community health plan. We need more detailed ‘vision statement guideline’ and the community health care centers of local government should effort to make more clear and complete their vision.

Correction: Rewritable full-color computer-generated holograms based on color-selective diffractive optical components including phase-change materials

Hwang, Chi-Young,Kim, Gi Heon,Yang, Jong-Heon,Hwang, Chi-Sun,Cho, Seong M.,Lee, Won-Jae,Pi, Jae-Eun,Choi, Ji Hun,Choi, Kyunghee,Kim, Hee-Ok,Lee, Seung-Yeol,Kim, Yong-Hae The Royal Society of Chemistry 2018 Nanoscale Vol.10 No.47

<P>Correction for ‘Rewritable full-color computer-generated holograms based on color-selective diffractive optical components including phase-change materials’ by Chi-Young Hwang <I>et al.</I>, <I>Nanoscale</I>, 2018, DOI: 10.1039/c8nr04471f.</P>

혈액투석중인 만성신부전 환자에서 골대사 지표로써의 Osteocalcin치

송치운,이진홍,안미애,윤환중,윤상임,성기양,이강현,송민호,이강욱,신영태,김영건,노흥규 충남대학교 의과대학 지역사회의학연구소 1993 충남의대잡지 Vol.20 No.2

Background : Serum osteocalcin is synthesized by osteoblast and has been shown to be sensitive indicator of bone turnover inpatients with various metabolic bone disease. In renal osteodystrophy, serum osteocalcin is elevated due to decreased renal clearance and elevated level of PTH. This study was done to evaluate the usefulness of serum osteocalcin as a marker of bone metabolism and the correlation with other biochemical markers of bone metabolism. Methods : We measured serum osteocalcin, calcium, phosphorus, ALP(alkaline phosphatase) and PTH(parathyroid hormone) in 37 patients with end stage renal disease on hemodialysis. Osteocalcin was determined by radioimmunoassay and PTH was determined by radioimmunometric assay. Results : 1) The mean level of serum osteocalcin in ESRD patients was 233.8± 218.2ng/ml which was significantly higher than that of controls(p<0.0001). 2) The mean level of serum PTH in ESRD patients was 40.5± 43.8pg/ml was significantly higher than that of controls(p<0.005). 3) There was a significant positive correlation between the level of serum PTH, ALP and the level of serum osteocalcin in ESRD patients. 4) By using multiple regression, PTH is most reliable factor that affect to elevated level of serum osteocalcin ( beta coefficient = 0.687, Sig T<0.05). Conclusion : Serum osteocalcin as a marker of bone metabolism in ESRD patients is more useful than other biochemical marker such as serum calcium, phosphorus, ALP and PTH is a most reliable factor that affect to elevated level of serum osteocalin.

영산강 상류일부의 水質汚染에 관한 調査硏究 : 산동교를 중심해서

류일광,이치영,강영식,김관천 광주보건대학 1990 論文集 Vol.15 No.-

Water quality of Young San river was examined for 3 months from April 12, 1989. to Jun 12, 1989. For checking the water quality 4 sampling position were selected. The results we obtained are as follows. 1. The average for Young San river was 6.6∼7.4 of pH, 3.6∼8.7mg/ℓof Dissolved dxygen (DO), 18.67∼33.47mg/ℓof chemical oxygen demand (COD), 47.66∼250mg/ℓ of suspended solid (SS), 37.83∼114.66mg/ℓ of N-hexane abstraction maters, 5.16∼6.63mg/ℓ of BOD. 2. The monthly average for Young San river was 6.5∼7.5 pH,3.5∼10.4mg/ℓ of DO. 15.07∼48.90mg/ℓ COD, 6.2∼10.2 mg/ℓ of BOC, 2∼250mg/ℓ of SS. 2∼124mg/ℓ of N-hexane abstraction mater, in April, 6.2∼7.5 of pH, 3.5∼8.2mg/ℓ of DO, 2.4∼5.7mg/ℓ BOD, 18.21∼32mg/ℓ of COD, 16∼123mg/ℓ of SS, 9.5∼95mg/ℓ of N-hexane abstraction matter, in May 6.9∼7.5 of pH, 3.8∼7.50mg/ℓ of pH, 3.8∼7.50mg/ℓ of DO, 4.0∼5.8mg/ℓ of BOD, 18.23∼of COD, 123∼163mg/ℓ of SS, 102∼125mg/ℓ of N-hexane abstraction matter in Jun. 3. The sampling positions averag for Young San San river was 6.9∼7.5 of pH, 7.5∼10.4mg/ℓ of DO, 15.07∼22.8mg/ℓ of COD, 3.5∼6.2mg/ℓ of BOD, 2∼125mg/ℓ of ss, 2∼102mg/ℓ of N-hexane abstraction matter in posiction 1.7.3∼7.5 of pH, 6.0∼7.5mg/ℓ of DO, 46.25∼52.05mg/ℓ of COD, 2.4∼8.5mg/ℓ of BOD, 58∼123mg/ℓ of SS, 62∼120mg/ℓ of N-hexane abstration matter in position 2. 6.2∼7.3 of pH, of pH, 4.23∼6.7mg/ℓ of DO, 4.9∼7,9mg/ℓ of BOD, 18.23∼36.75mg/ℓ of COD, 89∼152mg/ℓ of SS, 75∼123mg/ℓ of N-hexane abstraction matter, in position 3, 6.5∼7.2 of pH, 4.0∼10.2mg/ℓ of BOD, 3.5∼3.82mg/ℓ of DO, 23.6∼52.32mg/ℓ of COD, 123∼250mg/ℓ of SS, 95∼125mg/ℓ of N-hexane abstraction matter in position 4.

간호실무에서 신봉이론(Espoused theories)에 대한 탐색적 연구

서문자,김혜숙,이은희,박영숙,조경숙,강현숙,임난영,김주현,이소우,조복희,이명하,지성애,하양숙,손영희,권성복,김희진,추진아 성인간호학회 2001 성인간호학회지 Vol.13 No.1

As a nursing practice involves nurses' actions in a specific context of health care, this study has focused on exploring the espoused theories in nursing practice within the action science perspectives, Espoused theories are the belief, principles, and rationale expressed by the practitioner as guiding her/his actions in a situation of practice. The data were analysed qualitatively and 25 elements of espoused theories of nursing action were identified and clustered into 6 categories. The 25 elements of espoused theories are as follows: The clinical nurse worked in wholistic and individual nursing, focussed on the patient's needed, comfort and supportive nursing (5 theories of nursing goal) ; excellent skills, knowledge based, assessment and data collection, explaining, educating or a scientific basis(6 theories of nursing intervention): advocacy, value oriented, treatment, account- ability and commitment(4 theories of nursing ethics) ; human respect. partnership, trust(3 theories of patient-nurse relationship) : knowledgable, accumulated clinical experiences and personally lived experiences. positive perspectives(4 theories of nurse), role of intervention. rewarding peer relationship(3 theories of situations) The above mentioned espoused theories are similar to that of nursing textbooks which students learned through basic nursing education and almost the same as the Acts ofa Nurse in Korean. However, we are doubtful whether nurses actually do as they think. Therefore. it is recommended to review the theories-in-use in order to and any discrepancies between the espoused theories and the reality of nursing actions

Safety of subtotal or total colectomy with primary anastomosis compared to Hartmann procedure for left-sided colon cancer obstruction or perforation

Eun-Do Kim,Jin-Kwon Lee,Jin-Kyu Cho,Jae-Myung Kim,Ji-Ho Park,Ju-Yeon Kim,Sang-Ho Jeong,Young-Tae Ju,Chi-Young Jeong,Eun-Jung Jung,Young-Joon Lee1,Soon-Chan Hong,곽승진 대한종양외과학회 2019 Korean Journal of Clinical Oncology Vol.15 No.2

Purpose: Whether subtotal or total colectomy with primary anastomosis (PA) is safer than Hartmann procedure (HP) for left-sided colon cancer obstruction or perforation remains controversial. The purpose of this study was to compare postoperative morbidity, mortality, and defecation frequency between PA and HP for left-sided colon cancer obstruction or perforation. Methods: This retrospective study enrolled 54 patients from January 2014 to February 2018 who underwent emergency surgery due to left-sided colon cancer obstruction or perforation. Results: PA was carried out in 20 patients while HP was performed for 34 patients. Thirty-day mortality did not show significant difference between the two groups (15.0% vs. 14.7%, P=1.000). No anastomotic leakage occurred in PA group while three (8.8%) cases of stump leakage occurred in HP group. Stoma repair was performed for 13 cases (44.8%) and stoma reformation was performed for one case in HP group (7.7%). Stoma related complications occurred in five cases (17.24%). For patients after stoma repair, defecation frequency at 3 months after operation was 2.91±2.88 times per day in PA group and 2.86±2.63 times per day in HP group. At 1 year after operation, defecation frequency was changed to 1.40±1.12 times per day in PA group and 1.17±0.39 times per day in HP group. Conclusion: Primary ileosigmoid or ileorectal anastomosis for left-sided colon cancer obstruction or perforation is safe, and shows similar outcome of defecation frequency compared to H