• 한국게임학회 논문지
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• 제20권1호
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• pp.13-22
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• 2020

본 연구는 가상 물체의 무게감을 사용자에게 전달하여 몰입감 있는 가상현실 경험을 제공하는 컨트롤러에 관한 것이다. 무게감 전달의 수단으로 컨트롤러 내 무게 중심의 위치를 변화시키면 모멘트의 크기가 변화하는 개념을 활용하였다. 사용자가 무게차를 인지하는 무게 중심의 최소이동거리를 알아보기 위해 무게 중심의 위치를 변경할 수 있는 실험 장치를 제작하여 실험을 수행하였다. 그 결과, 시작 자극의 위치와 무관하게 약 5cm의 무게부 거리 차에서 두 물체 간의 무게 차이를 인지하는 것으로 나타났다. 향후 이러한 실험 결과를 반영하여 모멘트 변화에 따른 무게 인지의 최소이동거리 역치 값을 찾는 실험을 수행할 것이다.

• 한국통신학회논문지
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• 제28권5C호
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• pp.486-492
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• 2003

퍼지 ART 알고리즘에서 경계 변수는 임의의 패턴과 저장된 패턴과의 불일치(mismatch) 허용도를 결정한다. 이 경계 변수가 크면 입력 패턴과 저장 패턴 사이에 약간의 차이가 있어도 새로운 카테고리(category)로 분류하게 된다. 반대로 경계 변수가 작으면 입력 패턴과 저장 패턴 사이에 많은 차이가 있더라도 유사성이 인정되어 입력 패턴을 저장 패턴의 카테고리로 분류한다. 따라서 영상 인식에 적용하기 위해서는 경계 변수를 경험적으로 설정한다. 그리고 연결 가중치를 조정하는 과정에서 저장된 패턴들의 정보들이 손실되는 경우가 발생하여 인식률을 저하시킨다. 본 논문에서는 퍼지 ART 알고리즘의 문제점을 개선하기 위하여 퍼지 논리 접속 연산자를 이용하여 경계 변수를 동적으로 조정하고 저장 패턴과 학습 패턴간의 실제적인 왜곡 정도를 충분히 고려하여 승자 노드로 선택된 빈도수를 가중치 조정에 적용하는 개선된 퍼지 ART 알고리즘을 제안하였다. 제안된 방법의 인식 성능을 확인하기 위해서 운송 컨테이너 영상을 대상으로 실험한 결과, 기존의 ART2 알고리즘이나 퍼지 ART 알고리즘보다 클러스터의 수가 적게 생성되었고 인식 성능도 기존의 방법들보다 우수한 성능이 있음을 확인하였다.

• 한국식품저장유통학회지
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• 제6권1호
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• pp.66-70
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• 1999

The mechanism of natural removal of astringency and seasonal changes of tannin substance in sweet persimmon(Fuyu) and astrigent persimmon(Chungdo Bansi)were investigated. Tannin productivity of astringent persimmon fruit was higher than that of sweet perimmon fruit during growth. In the reactivity of tannin to acetaldehyde, it was observed that tannin from sweet persimmon have a milder chemical properties than that from astrigent persimmon. The threshold value of astringency on sweet persimmon tannin was higher than that of astrigent persimmon tannin. Tannin substances from sweet persimmon distributed mainly in lower molecular weight range at harvest stage, but those from astrigent persimmon distributed mainly in higher molecular weight range. Therefore, the natural removal of astringency was related to difference of tannin productivity, threshold value of astringency, reactivity and qualitative difference of tanni.

• Corrosion Science and Technology
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• 제8권5호
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• pp.171-176
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• 2009

The chloride threshold level (CTL) in mixed concrete containing, ordinary Portland cement (OPC), pulverized fuel ash (PFA) ground granulated blast furnace slag (GGBS), and silica fume (SF) is important for study on corrosion of reinforced concrete structures. The CTL is defined as a critical content of chloride at the steel depth of the steel which causes the breakdown of the passive film. The criterion of the CTL represented by total chloride content has been used due to convenience and practicality. In order to demonstrate a relationship between the CTL by total chloride content and the CTL by free chloride content, corrosion test and chloride binding capacity test were carried out. In corrosion test, Mortar specimens were cast using OPC, PFA, GGBS and SF, chlorides were admixed ranging 0.0, 0.2, 0.4, 0.8, 1.0, 1.5, 2.0, 2.5 and 3.0% by weight of binder. All specimens were cured 28 days, and then the corrosion rate was measured by the Tafel's extrapolation method. In chloride binding capacity, paste specimens were casting using OPC, PFA, GGBS and SF, chlorides were admixed ranging 0.1, 0.2, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0% by weight of binders. At 28days, solution mixed with the powder of ground specimens was used to measure binding capacity. All specimens of both experiments were wrapped in polythene film to avoid leaching out of chloride and hydroxyl ions. As a result, the CTL by total chloride content ranged from 0.36-1.44% by weight of binders and the CTL by free chloride content ranged from 0.14-0.96%. Accordingly, the difference was ranging, from 0.22 to 0.48% by weight of binder. The order of difference for binder is OPC > 10% SF > 30% PFA > 60% GGBS.

• 한국정보처리학회논문지
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• 제6권2호
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• pp.282-291
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• 1999

뉴스 비디오 데이터베이스 시스템을 구축하기 위해서는 장면변환 검출 기법이 매우 중요하다. 일반적인 분할기법으로 컬러히스토그램, $\chi$2 히스토그램, 그리고 Bin_to_Bin difference(B2B) 기법이 주로 이용되고 있다. 본 논문에서는 NTSC 표준에 따른 가중치를 적용하여 보다 효율적인 장면변환 검출 알고리즘을 제안한다. 제안된 방법은 컬러 히스토그램에서 RGB의 값들을 각각 따로 계산함으로써 히스토그램 구성 및 비교에 필요한 계산시간을 단축하며, $\chi$2 히스토그램에서의 차이 값을 강조하여 임계치 선택을 용이하게 하는 장점을 제공한다. 이 알고리즘의 일반적인 성능 평가를 위하여 본 논문에서는 KBS, MBC, SBS, CNN 및 NHK의 뉴스 비디오들을 실험 도메인으로 하여 이용한다. 실험 결과에서, 제안한 방법은 기존 방법들보다 장면변환 검출에 더 효율적임을 알 수 있고, 임계값들을 자동적으로 할 수 있는 기반을 제시한다.

• Journal of Nutrition and Health
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• 제26권5호
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• pp.625-638
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• 1993

The purpose of this study was to observe the relationship of dietary factors to blood pressure in 5th and 6th grade school children. Salt threshold, salt preference and nutrition knowlege about blood pressure were tested. Twenty-four hour urines were collected for the measurements of the volume and concentrations of sodium, potassium, chloride, calcium, phosphorus, creatinine and urea nitrogen. 1) Mean systolic and diastolic blood pressure of elementary school children were 106.8/67.6mmHg in males and 108.7/69.5mmHg in females. Seven children(4%) of total subjects were found to be hypertensive. Their mean blood pressure was 130.0/86.4mmHg. 2) Urinary excretions of creatinine and urea nitrogen during twenty-four hours were 621.1mg and 1524mg, respectively. The mean daily urinary sodium excretion was 2940mg, which is equivalent to 7.37g NaCl. 3) The daily urinary excretions of other minerals were as follows; potassium was 1301mg, chloride, 4991mg, calcium, 55.7mg and phosphorus, 700.03mg. 4) Salt preference of hypertensive children90.473$\pm$0.275) was significantly higher than those of normotensive children(0.473$\pm$0.213%), but salt threshold was lower in hypertensives(0.105$\pm$0.04%) than normotensives(0.081$\pm$0.022%) (p<0.05). INdices for assessing obesity, such as body weight, triceps skinfold, weight for heigth and body surface area, were high in hypertensive children than normotensive children(p<0.05). But there was no significant difference in energy and nutrient intakes between two groups. 5) Various anthropometric measurements had positive correlations with blood pressure, but body muscle mass(%) had a negative correlation with blood pressure. And daily energy and nutrient intakes were not related to blood pressure. 6) Blood pressures-both systolic and diastolic-were significantly correlated with urinary excretions of potassium and chloride. Daily sodium excretion was related to systolic blood pressure, but no related to diastolci blood pressure. There was no relationship of salt threshold to salt preference, and neither threshold nor preference was related to blood pressure. Results of this study suggest that nutrition education program for children including the information about desirable food habits for the prevention of hypertension should be developed.

• 한국정보통신학회논문지
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• 제24권5호
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• pp.609-615
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• 2020

현대 사회는 4차 산업 혁명과 더불어 디지털 장비의 사용이 증가하여 영상 및 신호처리의 중요성이 높아지고 있으며, 이와 함께 잡음 제거에 관한 연구가 활발하게 이루어지고 있다. 본 논문은 랜덤 임펄스 잡음 제거를 위한 스위칭 필터 알고리즘을 제안한다. 제안한 알고리즘은 영상에 존재하는 잡음 수준을 판단하여 임계값을 구하며, 임계값은 입력 화소값과 기준치의 차이와 비교되어 필터의 가중치 스위칭 과정에 사용한다. 필터의 최종 출력은 스위칭에 따라 화소 가중치 및 변형된 가중치 메디안 필터를 적용하여 추정치를 구하며, 추정치와 입력 화소값을 비교하여 최종 출력을 구한다. 제안한 알고리즘의 성능을 평가하기 위해 시뮬레이션 및 PSNR 등을 이용하여 기존 방법들과 비교하였다.

• 정신신체의학
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• 제6권1호
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• pp.22-27
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• 1998

DSM-IV 진단 기준에 의하여 신체화 장애, 미분화 신체형 장애, 그리고 달리 분류되지 않은 신체형 장애여성 환자 13명과 정상 여성 20명을 대상으로 압통에 대한 통각 역치와 혈청 testosterone을 측정하여 다음과 같은 결과를 얻었다. 1) 가변 하중 압통 예민도 측정기 (Variable Weight Pressure Algometer)로 측정한 통각 역치는 환자군이 153.8${\pm}$39.5gm/$0.05mm^2$로서 대조군의 197.5${\pm}$66.7gm/$0.05mm^2$보다 유의하게 낮았다(p<0.05). 2) 혈청 testosterone치는 환자군에서는 0.175${\pm}$0.081ng/ml였고, 대조군에서는 0.174${\pm}$0.108ng/ml로서 양군간에 유의한 차이가 없었다. 3) Testosterone과 통각 역치와의 상관관계를 보면, 환자군에서는 혈청 testosterone치와 통각 역치 사이에 유의한 정적 상관관계가 있었으나(r=0.632, p<0.05, two tailed, Pearson's correlation test), 대조군에서는 유의하지 않았다(r=-0.405). 이상의 결과로 보아 신체화 장애 환자와 정상인 사이에 통각 예민도 조절 기전이 서로 다를 수 있다고 사료 된다.

• 동의생리병리학회지
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• 제21권3호
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• pp.748-754
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• 2007

Electroacupuncture is the combined treatment of mechanical and electric stimuli on the needle head, on which electricity runs after acupuncturing at the acupuncture points. It is reported that its treatment effect depends on the parameter of stimulus, which is wave of stimulus, frequency, voltage, and duration of electric current. To get the effective treatment, stimulus intensity over threshold is needed. We planned to experiment whether acupuncture effect is affected by sex, age, and weight. After we conducted electric stimulus at Zusanli(ST 36) which is known to increase small intestinal motility in normal rats, we observed the effects and got the following results. Though the increased effects of small intestinal motility of electro-acupuncture at Zusanli(ST 36) did not show the difference of sex, this effect was observed to have a tendency to decrease according to weight increase without distinction of sex. But the effect of electro-acupuncture shown in 4, 5, 7 weeks old without distinction of sex was observed to have a tendency to decrease with the growing of weeks-old in the male rat group. And the significant change without specific tendency was observed in the 4, 5 weeks old female rat group. This result suggested that sex, weight, and age should be considered to get the efficient electro-acupuncture. The more experimental study should be advanced to investigate the correlation between the factors that can affect the acupuncture treatment, and, afterward, the interconnection into the clinical use.

• Nutrition Research and Practice
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• 제13권5호
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• pp.399-409
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• 2019

BACKGROUND/OBJECTIVES: This study was designed to provide scientific evidence on the effectiveness of worksite-based dietary intervention to reduce obesity among overweight/obese employees. MATERIALS/METHODS: Electronic search was performed using Ovid Medline, Embase, Cochrane Library, and CINAHL databases. The keywords used were "obesity," "nutrition therapy," and "worksite." The internal validity of the randomized controlled trials (RCTs) was assessed using the Cochrane's Risk of Bias. Meta-analysis of selected studies was performed using Review Manager 5.3. RESULTS: A total of seven RCTs with 2,854 participants were identified. The effectiveness of dietary interventions was analyzed in terms of changes in weight, body mass index (BMI), total cholesterol, and blood pressure. The results showed that weight decreased with weighted mean difference (WMD) of -4.37 (95% confidence interval (CI): -6.54 to -2.20), but the effectiveness was statistically significant only in short-term programs < 6 months (P = 0.001). BMI also decreased with WMD of -1.26 (95% CI: -1.98 to -0.55), but the effectiveness was statistically significant only in short-term programs < 6 months (P = 0.001). Total cholesterol decreased with WMD of -5.57 (95% CI: -9.07 to -2.07) mg/dL, demonstrating significant effectiveness (P = 0.002). Both systolic (WMD: -4.90 mmHg) and diastolic (WMD: -2.88 mmHg) blood pressure decreased, demonstrating effectiveness, but with no statistical significance. CONCLUSIONS: The worksite-based dietary interventions for overweight/obese employees showed modest short-term effects. These interventions can be considered successful because weight loss was below approximately 5-10 kg of the initial body weight, which is the threshold for the management of obesity recommended by the Scottish Intercollegiate Guideline Network (SIGN).