Impact of the oxygen functional group of nitric acid‑treated activated carbon on KOH activation reaction

Ji‑Hyun Kim,Sang Youp Hwang,Jung Eun Park,Gi Bbum Lee,Ho Kim,Seokhwi Kim,Bum Ui Hong 한국탄소학회 2019 Carbon Letters Vol.29 No.3

To prepare activated carbon with a high specific surface area, oxygen functional groups (OFGs) that can serve as useful electron donors during KOH activation were treated with nitric acid and incorporated into activated carbon. OFGs are incorporated differently according to the surface characteristics of starting materials. Up to 22.46% OFGs are incorporated into wood-based activated carbons (WACs), the C=O, COOH contents was 1.90, 17.05%, respectively. Whereas up to 12.82% OFGs are incorporated into coconut shell-based activated carbons, the C=O, COOH contents was 4.12, 6.15%, respectively. The OFGs used for increasing the specific surface area are the carbonyl group, and as the content of the functional group increases, the carbonyl group spreads to the carboxyl group. The specific surface area of activated carbons increased by 10–68% with an increase in the carbonyl group up to 6% (maximum point of carbonyl group). On the other hand, the specific surface area for WACs increased when the carboxyl group was 10% or below, but decreased by 6–15% when it increased to 10% or excess.

골프 우드 드라이버 스윙 운동 시 에너지 소비량과 운동 강도

황경식,황지현,이사겸 한국스포츠리서치 2005 한국 스포츠 리서치 Vol.16 No.2

The purpose of this study is to provide basic data for exercise prescription by investigating for exercise intensity and energy expenditure while swinging golf fairway drive wood club. The subjects of this study are 14 male and female college students. Body composition, VO₂max. HRmax by testing graded exercise test and energy expenditure while 10 minutes golf swing using automatic gas analyzer Vmax 229(sensormedics; U.S.A) and heart rate monitored system Polar system(U.S.A) are investigated. SPSS(Version 11.0) was using as statistical method. Independent sample t-test. For all tests, alpha was set at .05 initially in significance. The results were as follows. Fist, Average heart rate was lower in male as 111.9±7.1beats·min^(-1) then in female as 115.4± 14.8beats·min^(-1). Average percent HRmax was lower in male as 56.1±2.8% then in female as 60.2±8.2. However. there was no significant difference between two groups. Second. Average RPE was lower in mele as 11.7±0.5 than in female as 12.0±0.6. However, there was no significant difference between two groups. Third, Average VO₂ was higher in male as 0.83±0.04ℓ·min^(-1) than in female 0.50±0.111ℓ·min^(-1), Average VO²per kg was higher in male 10.9 7±0.99㎖-kg^(-1)-min^(-1) than in female as 8.74±1.22㎖-kg^(-1)-min^(-1). There were significant differences between two groups. Forth. Average %VO₂max was higher in male as 28.1±3.9% than in female as 26.1±5.6. However, there was no significant difference between two groups. Fifth, Energy expenditure per minute was lower in male as 1.83±0.03kcal-min^(-1). than in female 1.81±0.08kcal-min^(-1). However, there was no significant difference between two groups. Energy expenditure per kg was lower in male as 0.063±0.005kal·kg^(-1)·min^(-1) than in female as 0.086±0.0111kal·kg^(-1)·min^(-1). There was significant difference between two groups. In conclusion, no significant differences were found in exercise intensity of golf swing for male and female subjects. Energy expenditure of female subjects were shown higher than male subjects. Energy expenditure must compared by relative divided by weight(kg) value.

간호대학생이 지각하는 임상실습지도자의 교수효율성과 임상실습만족도의 관계

황현아,김희진,김예지,이규희,이영롱,박성희,손수빈 이화여자대학교 간호과학대학 2012 이화간호학회지 Vol.- No.46

Purpose: The purpose of this study was to investigate the relationship between teaching effectiveness and clinical practice satisfaction among nursing students. Method: The subjects of this study were 107 junior and senior nursing students in E university. Data were collected using self-reported questionnaire including general and practicum related characteristics, teaching effectiveness of clinical instructors and clinical practice satisfaction from September 12 to September 21, 2011. Collected data were analyzed by SPSS 19 program using t-test, ANOVA with Scheffe test, and Pearson`s correlation coefficients. Result: The mean score of teaching effectiveness was 3.35(±.51), and mean of clinical practice satisfaction was 3.19±.47. There were significant differences of teaching effectiveness of clinical instrutor by satisfaction of overall clinical practicum(F=8.332, p<.001), satisfaction of practice hour(F=3.230, p=.044), and satisfaction of major(F=9.883, p<.001). There were significant differences of clinical practice satisfaction by grade(t=2.274, p=.025), motive of choosing nursing science as a major(F=3.329, p=.007), satisfaction of overall clinical practicum(F=17.437, p<.001), satisfaction of practice hours(F=9.925, p<.001), and satisfaction of nursing major(F=12.748, p<.001). Relationship between teaching effectiveness of clinical instructor and clinical practice satisfaction showed positive correlation(r=.704, p<.001). Conclusion: In this study, teaching effectiveness of clinical instructor was related with clinical practice satisfaction. Therefore, we should consider improving teaching effectiveness of clinical instructor to improve clinical practice satisfaction.

에어컨 냉각 팬용 브러쉬레스 DC 전동기의 역기전력 분석에 대한 연구

조정현,김지현,정정원,황흥식,이치우 경성대학교 공학기술연구소 2012 공학기술연구지 Vol.18 No.-

Compared to conventional dc motors having the combination of commutators and brushes, a brushless DC (BLDC) motor is one of the highly efficient motors due to its electrical commutation without a brush, and this feature allows the BLDC otor to be more suitable for an application requiring no maintenance due to mechanical wear between a commutator and a brush. Also, the BLDC motor has a few benefits over both a dc motor and an induction motor such as high dynamic response, high efficiency, logn life span, and low noise in wide speed-torque region. This paper investigates the variation of voltage induced in phase windings in a BLDC motor in several cases with respect to stack length, steel grade, and coil material. This study is numerically conducted and it is verified from the theoritical point of view by comparing the result of simulation with that of experimental measurement.

Fuzzy 이론을 이용한 건설공사의 리스크 분석 방법

황지선,한현종,신종현,이찬식 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

The purpose of this paper is to develop a risk analysis method using fuzzy theory for construction projects. Construction risks are generally evaluated as vague linguistic value by subjective decision making. Fuzzy theory is a proper method to quantify vague conditions of construction activities. Therefore, this study utilizes fuzzy theory to analysis construction risks. Risks are identified and classified into two levels such as upper level risk factors and lower level risk factors by RBS(risk breakdown structure). The risk exposure of lower level risk factors is assessed using fuzzy inference individually and their absolute and relative weights are estimated by fuzzy measure and AHP respectively. The estimated risk exposures and weights are aggregated to assess the risk exposure of upper level risks by Choquet fuzzy integral.

중년 여성에서 발생한 집합관 신세포암 1 예

황인성;정재현;유지형;성락희;노충희;정재용;김현정 인제대학교 2011 仁濟醫學 Vol.32 No.-

Collecting duct renal cell carcinoma (CDRCC) or Bellini duct carcinoma is a rare type of renal cell carcinoma (RCC), accounting for 0.4% to 1.8% of all RCC. CDRCC is considered to originate from the collecting duct of the kidney and it has a poor prognosis. However, the clinical features of CDRCC remain poorly understood, mainly because only studies with a small series or case reports have been published to date. We experienced a case of CDRCC of kidney.

순환기 내과로 자문의뢰된 환자의 임상상

황진용,최지용,손상균,조용근,채성철,전재은,박의현 慶北大學校 醫科大學 1996 慶北醫大誌 Vol.37 No.4

목적 : 순환기내과 영역은 많은 과로부터 자문의뢰를 받는 영역으로 알려져 있다. 특히 최근 우리나라의 순환기질환의 유형이 변화되고 입원환자가 고령화되면서 동반된 심질환의 유병율도 증가하고있다. 이에 저자들은 타과로 입원하여 순환기내과로 자문의뢰되는 환자의 임상상과 3차병원인 경북대학교병원에서의 순환기내과자문의 유용성 등을 평가하여 향후 순환기질병에 대한 협의진료에 도움을 주고자 본 연구를 시행하였다. 방법 : 1995년 3월부터 순환기내과로 공식자문의뢰된 첫 100명을 대상으로 전향적으로 연령, 의뢰이유, 최종진단명, 수술과의 관련성 여부, 순환기내과의 최종조치, 타과의 순응도 등을 조사하였다. 결과 : 1) 자문을 의뢰한 환자는 평균 58±16(15-89, 중앙치 61)세였고 60세이상의 환자가 57%로 고령의 환자가 많았다. 2) 내과계열 25%, 외과계열 75%로 외과계열의 자문이 많았고 일반외과가 26%로 가장 많았고 내과의 다른 분과가 12%, 신경외과 12%, 정형외과 11%, 흉부외과 11%, 신경과 11% 등의 순이었다. 외과계열중 수술을 시행한 경우는 58례로 이중 응급수술이 13례였다. 술전 위험도 평가를 위한 자문이 38례에서 있었는데 순환기적인 문제로 수술을 받지 못한 경우는 2례(1례는 허혈성 심질환, 1례는 심낭질환)이었다. 이때 응급수술을 제외한 입원일과 술전 자문일파의 간격은 평균 3±7일(입원일-42일)이고 술전 자문일과 수술일과의 간격은 평균 6±4일(1-16일)이었다. 3) 타과의 의뢰이유는 심전도 이상이 36례, 높게 측정된 혈압이 20례, 순환기질환의 과거력 17례, 환자의 증상 때문인 경우가 10례였고 심전도의 이상중에는 부정맥이 18례, 이상 Q파 6례, ST절 이상이 5례, 각차단이 3례의 순이었다. 순환기과거력 중에는 허혈성 심질환이 6례, 현재 혈압은 정상이나 고혈압의 과거력이 있는 경우가 4례 순이었고 환자의 증상은 흉통 6례, 호흡곤란이 3례, 기절이 1례였다. 4) 자문후 최종진단이 가능했던 91례를 진단별(총 97 진단명)로 나누어 보면 고혈압이 28례, 부정맥이 16례, 허혈성 심질환이 14례, 판막질환이 11례, 순환기질환이 아닌경우가 19래였다. 이들중 추적진료가 필요하다고 응답한 경우가 57례였으나 순환기내과 외래에 1번이상 추적진료한 경우는 32례(56%)로 환자의 순응도는 낮았다. 결론 : 순환기내과의 자문의뢰는 고령자에게 많았고 수술과 관련된 경우가 많았으며 심전도의 이상이 의뢰이유로 가장 많았으며 진단별로는 고혈압과 부정맥이 가장 많았다. 그리고 순환기적인문제로 수술을 받지 못한 경우는 드물었고 자문후 지속적인 추적진료를 위해 환자의 교육이 필요하겠다. Objective : Clinical characteristics of the patients with cardiovascular diseases in the general hospital have been changed and prevalance of co-existing cardiovascular disease in the patients who were admitted for non-cardiac diseases has been increased remarkably as the proportion of elderly patients increased rapidly in Korea. We evaluated clinical features of the patients consulted for cardiological evaluation and effectiveness of the consultation in the setting of tertiary general hospital, Kyungpook University Hospital. Method : One hundred patients were studied between January 1995 and January 1996. They were evaluated for the reason of consultation, final diagnosis, final recommendation from cardiologists and its impact on the management of the patients, and compliance of the consulting departments. Results : 1) The ages ranged between 15 and 89 (mean 58±16, median 61) years, 57 patients were male and 43 female. Fifty seven patients were older than 60 years. 2) Consultations from surgical parts were 75 patients. Consultation from general surgery was most frequent (26%), followed by other divisions of internal medicine (12%), neurosurgery (12%) and orthopedic surgery (11%), chest surgery (11%), neurology (11%), obstetrics and gynecology (8%), urology (4%), ophthalmology (2%), dermatology (2%), ENT (1%). Among 75 patients from surgical parts, operation was done on 58 patients, including 13 emergency cases. Preoperative cardiac risk evaluation was the reason of consultation in thirty eight patients, of which operation could not be done in only 2 patients (one had severe ischemic heart disease, the other large pericardial disease). Interval between consultation day and operation day was 6±4 days (1-6 days). 3) Reasons for cardiac consultation were electrocardiographic (ECG) abnormalities in 36 patients, high blood pressure in 20 patients, previous cardiovascular diseases in 17 patients, symptoms of the patients in 10 patients. Among EGG abnormalities, arrhythmias was the reason in 18 patients, abnormal Q waves in 6 patients, ST-T segment abnormalities in 5 patients, bundle branch block in 3 patients. Among previous cardiovascular disease, presence of ischemic heart disease was the reason in 6 patients, previous hypertension in 4 patients. Chest pain was the reason of the consultation in 6 patients, dyspnea in 3 patients, syncope in 1 patient. 4) Definite diagnoses could be made in 91 patients with 96 diagnoses which were hypertension and its complications in 28, arrhythmia with underlying disease in 16, ischemic heart disease in 14. valvular heart disease in 11, non-cardiovascular disease in 19. Cardiological follow up was recommended in 57 patients. However, 25 patients (44%) were lost to follow-up. Conclusion : Cardiological consultation was frequent in the elderly patients. Most frequent reason for consultation was EGG abnormalities. Hypertension or arrhythmia was most common final diagnosis. Inoperability due to cardiovascular problems were rare.

치과용 금합금의 표면처리에 따른 교정용 브라켓의 전단결합강도 변화

민지현,황현식,이기헌,박병주 전남대학교 치과대학 2000 전남치대논문집 Vol.12 No.1

A bracket bonding to the dental gold alloy shows a lower bond strength than the natural teeth, and this can be a possible source of subsequent bond failure. This study aims to evaluate the effect of various gold alloy surface treatment techniques on shear bond strength between the orthodontic adhesives and the gold alloy and to find ways of increasing the bond strength. Two hundred and forty specimens made of the dental gold alloy were divided into twelve groups based on the combination of surface treatment methods(non-surface treatment, sandblasted, sandblasted plus tin-plated, and sandblasted plus intermediate adhesive) and adhesive systems(Ortho-one, Panavia 21, Superbond C&B). The specimens with brackets bonded were placed in distilled water at 37℃ for 24 hours and shear bond strength was measured by a universal testing machine. The results were as follows: 1. All surface-treated groups showed a significantly higher shear bond strength than non-surface-treated groups. 2. The sandblasted plus tin-plated group showed a significantly higher shear bond strength than the sandblasted group only when Panavia 21 was involved. 3. The sandblasted plus intermediate adhesive group showed a significantly higher shear bond strength than sandblasted group regardless of the type of adhesive used. 4. Of the three resin adhesive types, the Superbond C&B showed the highest bond strength, followed by Panavia 21 and Ortho-one. These findings suggest that a combination of sandblasting and intermediate resin treatment is desirable in order to enhance bracket bond strength regardless of adhesive types.

한국과 베트남 사람들의 정서 체험

김지현,판후옹,황석현,민경환 서울大學校 社會科學大學 心理科學硏究所 1997 心理科學 Vol.6 No.2

본 연구는 한국과 베트남 사람들의 정서 체험에 관한 연구이다. 정서의 보편성과 문화적 변산성에 관한 이론적 연구를 위한 자료를 수집하기 위한 목적으로, 사람들이 다양한 정서 상태들을 경험할 때 느끼는 생리적 반응, 언어적 표현, 행동 반응, 주관적 느낌 및 그러한 정서를 유발하는 상황에 초점을 두어 베트남 사람들과 한국 사람들의 정서 체험 내용의 공통점과 차이점을 알아보았다. 베트남에서는 국립 베트남 대학교와 국립 호치민 대학교에 재학중인 215명이 본 연구에 참여하였고, 한국에서는 60명의 국립 서울대학교 학부생들이 참가하였다. 기쁨, 슬픔, 공포, 분노의 네 가지 정서가 정서 체험에 관한 자기-보고 질문지를 사용하여 연구되었다. 결과는 다음과 같다. 첫째, 특정한 정서를 유발하는 원인이 되는 선행 사건들의 보편성을 밝혔다. 다음으로, 다양한 정서를 체험할 때 나타나는 반응들의 패턴에 있어서 문화간 변산성이 나타남을 확인하였다. 세 번째로 여성과 남성의 정서 체험의 내용에서 몇 가지 흥미로운 차이점들이 발견되었다. 마지막으로 후속 연구를 위한 시사점들이 논의되었다. The emotional experiences of Koreans and Vietnamese were studied. In order to collect the data for the purpose of conducting a theoretical study on universality of emotions and cultural variations, the similarities and differences in the various aspects of emotional experiences of Koreans and Vietnamese were examined, which included physiological responses, verbal expressions, behavioral patterns, subjective feelings, and the antecedent events that were the causes of the emotional experiences. 215 Vietnamese undergraduates from Vietnam National University and Ho Chi Min University and 60 Korean undergraduates from Seoul National University participated in this study. Using a self-report form, emotional experiences of joy, sadness, fear, and anger were examined. As the result, universality of antecedent events for specific emotions was confirmed. Cultural variations in the emotional response patterns were confirmed as well. Finally, some interesting sex differences in emotional experiences were found. Implications and suggestions for the future study were discussed.

콜리플라워를 이용한 피클제조 최적화

정현아,윤지영,황재선,주나미 한국식생활문화학회 2004 韓國食生活文化學會誌 Vol.19 No.2

The purpose of this study was to determine the organoleptic characterisitcs of cauliflower pickles made in various compounding ratio according to central conposite design for optimum organoleptic characteristics of the cauliflower pickles. The optimum mixing condition of cauliflower pickles were optimized, using central composite design with 3 variables and 3 levels, by response surface methodology. The various kinds of cauliflower pickle were made in various compounding ratio of vinegar, salt and sucrose - critical ingredients of pickle recipe - and were presented to reliable panels, who graded the subjects in 7 degrees for 4 items : color, lavor, hardness and overall quality. The optimum mixing conditions of cauliflower pickle were 603.50g of vinegar, 80.13g of salt and 251.079 of sucrose in the maximum point of overall quality.