• Journal of the Korean Institute of Intelligent Systems
• /
• v.8 no.6
• /
• pp.1-11
• /
• 1998

In this work, we propose a modeling method based on an artifical intelligence technique for a stem generator in a nuclear power plant. Modeling the steam generator is known to be difficult due to several facts; especially, the dynamics of the steam generator is nonminimum phase which is mainly caused by the swell and shrink phenomena from thermal effects. In order to overcome this difficulty, we adopt so-called logic processor whose structure itself has a logical meaning to be easily established and also efficiently learned. Such a manner, we could derive an useful model simulating the dynamics of the steam generator in a nuclear power plant.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.19 no.5
• /
• pp.1104-1109
• /
• 2015

Due to the rapid growth in digital contents, it is important for us to design a high speed and secure encryption algorithm which is able to comply with the existing and future needs. This paper proposes an alternative approach for self-decimated LM-128 summation sequence generator, which will generate a higher throughput if compared to the conventional generator. We design and implement a threshold clock-controlled LM-128 and prove that it has a lower clock cycle and hence giving a higher key stream generation speed. The proposed threshold clock-control LM-128 generator consists of 256 bits inner state with 128 bits secret key and initialization vector. The cipher achieves a security level of 128 bits to be adapted to the digital contents security with high definition and high quality.

• The Korean Journal of Pharmacology
• /
• v.30 no.3
• /
• pp.337-342
• /
• 1994

It is well known that angiotensin converting enzyme inhibitors(ACEIs) increase endothelium-dependent relaxation in aortic strips of spontaneously hypertensive rats(SHR) and this increase in relaxation may be due to altered endothelial nitric oxide breakdown. But there are few studies on the effect of the angiotensin II receptor blocker on the nitric oxide-mediated relaxation. So we attempted to investigate the effect of angiotensin II receptor blocker on the nitric oxide-dependent relaxation in isolated aorta of SHR. Two week-treatment of losartan (30 mg/kg/day) increased the acetylcholine$(10^{-9}\;to\;10^{-5}\;M)$-and histamine$(10^{-8}\;to\;10^{-4}\;M)$-induced relaxation in endothelium intact strips but 90 minutes-treatment of losartan $(10^{-4}\;M)$ showed no increase in relaxation. The phenylephrine $(10^{-7}\;M)$-induced contraction, repeated every 2 hours, was diminished gradually following lipopolysaccharide (LPS)-treatment $(100\;{\mu}g/ml)$ but there was no significant difference in enalapril- and losartan-treated group compared with control group. These results suggest that activity of the endothelial constitutive NO synthase may be changed by chronic treatment of angiotensin II receptor blockers and ACEIs but angiotensin II antagonist and ACEI have no effect on the inducible NO synthase activity in the isolated aorta of SHR

• Polymer(Korea)
• /
• v.35 no.5
• /
• pp.467-471
• /
• 2011

PET bottle is manufactured by blow molding the preform, which is molded by injection molding. The neck part of the preform of PET bottle for juice or grain-based beverage is crystallized before blowing to improve heat resistance at the entrance of the bottle. However, residual stress, developed during injection molding of preform, prevents the crystallization. In order to release the residual stress in the preform, the preform is annealed after the injection molding. If the residual stress is reduced by optimizing the injection molding conditions of preform the annealing time would be shortened. In this study, the optimum conditions for minimizing the residual stress and increasing dimensional accuracy of the injection molded preform are suggested through CAE analysis. In order to optimize the molding conditions, minimizing residual stress and shrinkage, computer simulations have been carried out with help of design of experiment scheduling. Injection temperature, initial packing pressure and filling time were selected for control parameters. Residual stress was affected by injection temperature and filling time. Shrinkage was affected by injection temperature. It was found that maximum residual stress, distribution of residual stress and shrinkage were decreased by 22%, 40% and 25%, respectively at an optimum molding condition compared with the results of previous molding condition.

• Journal of Nutrition and Health
• /
• v.16 no.3
• /
• pp.209-215
• /
• 1983

In high sodium societies, the incidence in blood pressure with childhood growth is more abrupt than the rate of rise in low sodium populations. Thus, it appears that a lower level of dietary sodium intake is required to correct established hypertension and to prevent its appearance In present work, an investigation was made to estimate the correlation between urinary sodium, potassium and creatinine excretion, weight, height, upper arm circumference, blood pressures and the number of heart rate. Sixty- four children aged 12-16 years (41 boys and 23 girls) were measured. Twenty -four-hour urinary sodium and potassium excretion averaged 132.8 mEq and 42.1 mEq in boys, 126.4 mEq and 41.3 mEq in girls. Twenty- four -hour urinary creatinine excretion averaged 795.7 mg and 744.3mg in boys and girls, respectively. Systolic and diastolic blood pressure were 117.6mmHg and 49.7mmHg in boys, 95.5mmHg and 58.2mmHg in girls. Systolic blood pressure correlated positively weight, height and urinary creatinine but diastolic blood pressure correlated positively with upper arm circumference and negatively with urinary potassium. It was concluded that urinary sodium does not explain the blood pressure.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.1
• /
• pp.11-20
• /
• 1996

본 조사는 경기도 용인에 위치한 명지대학교의 남녀 대학생 202명의 대상으로 일반 환경과 혈철지질, 혈압, 체지방량 측정 검사를 중심으로 이루어졌으며, 조사 분석한 결과를 요약하면 다음과 같다. 1. 조사 대상자의 신체발달 상황을 보면 남자의 평균 신장과 체중 및 비체중치는 173.1cm, 65.9kg, 38.03이였고, 여자는 16.7cm, 52.4kg, 32.6로 한국인 성인의 표준치와 매우 유사한 수치였다. 체지방량 비율은 남자 16.4, 여자 24.0으로 나타 설별에 따른 차이가 뚜렸하였다. 2, 조사 대상자들의 수축기와 이완기의 혈압은 평균 $125\pm123mmHg,$ $77.2\pm11.1mmHg이고,$ 남자와 여자의 수축기 혈압은 각각 $132.3\pm1.9mmHg,$ $118.1\pm1.6mmhg로$ 정상 범위였다.확장기 혈압은 남녀 각각 $80.5\pm11.0mmHgm$ $73.9\pm102.m,Hg였으며$ 역시 정상범위에 포함되었다. 3. 혈청 지질의 검사 결과는 Tc는 남자 175.2mg/dl, 여자 183.6mg/dl로 나타났고 TG는 남자 108.4mg/dl, 여자 72.0mg/dl로 나타나 통RP적으로 유의한 차이가 있었다. (p<0.05). 또한 HDL-C는 남자 59.6mg/dl , 여자 64.3mg/dl 로 성별에 다른 유의적인 차이를 보였고 (p<0.05), LDL-C도 역시 남자 93.9mg/dl, 여자 104.8mg/dl로 나타나 통계적으로 성별에 다른 차이가 뚜렷하였다. (p<0.01). 조사결과 다른 연령층의 성인과는 달리 TG를 제외한 TC, H이-C, L이-C에 있어서 남자가 여자 보다 더 낮은 수치를 보였다. 4. 혈압에 따라 세 그룹으로 분류한 후 혈청 지질과의 관계를 보면, 수축기 혈아이 증가함에 따라 TC, TG, LDL-C은 증가하는 경향을 보였으며, HDL-C은 감소되었으나 통계적으인 유의성은 없었다. 이완기혈압의 겨우 89mmHg 이하 보다 90~94mmHg의 경우에 유의적으로 증가되었으며 (p<0.05) HDL-C은 감소하였으나 유의성은 없었다. 5. 혈정 지질과 비만도의 관계는 남녀 모두 양의 상관관계를 나타냈으나 여자보다 남자에서 뚜fut이 나타났다. 남자의 겨우 TC의 수치가 KI에 따라 110% 미만일 때 $169.7\pm31.5mg/dl,$ 110~120%일 때 $193.8\pm36.8mg/dl,$ 120% 이상 일 때 $202.2\pm29.3mg/dl로$ 비만도에 따른 유의적인 증가를 (p<0.05)보여주었으나 여자의 경우는 유의적인 차이가 없었다. TG의 수치는 남자의 경우 KI가 110%미만인 그룹은 $102.9\pm108.2mg/dl,$ 120% 이상인 그룹은 $112.2\pm40.0mg/dl로$ 비만도가 증가함에 따라 TG가 증가되었으나 유의적인 차이는 없었으며, 여자의 경우 유의적인 차이가 없었다. 남자의 경우 HDL-C은 비만도가 증가함에 따라 유의적으로 감소하는 경향을 보였으나(p<0.05) 여자의 경우는 유의적인 차이가 없었다. 6. 조사 대상자의 체지방량 측정결과 체기방률은 남자의 겨우 16.4% 여자의 겨우 24.0%로 나타나 여자의 체지방률이 남자보다 높았다. 7. 신체계측치, 혈압, 혈청 지질간의 상관관계를 살펴보면 TC, TG는 KI, BMI와 유의적인 양의 상관관계를 보였고 (p<0.01), HCL-C은 비체중, BMI, LBM, TBM와 유의적인 음의 상관관계를 보였으며, (p<0.01), KI, SBP와도 음의 상관관계를 보였다. (p<0.05), LCL-C는 KI와 유의적이인 양의 상관관계를 나타내었으며 (p<0.01) BF%, TBF, BMI와도 양의 상관관계를 나타냈었다. (p<0.05). 또한 LPH, Al는 모두 나이, 비체중, BMI, KI와 유의적인 양의 상관관계를 나타내었다. (p<0.01). 이상을 종합해 보면 본 조사 대상자들은 비만도가 높아질수록 혈청 지질 수준이 놓았으며, 이완기 혈압도 형철 지질과 상관관계를 나타났다. 대학생의 혈청 지질과 체지방에 대한 자료가 부족함을 고려할 때, 본 조사자료가 학생의 혈청지질의 체지방에 대한 기초 자료로서 이용될 것을 기대하며 보다 다각적인 연구가 이루어지기를 바라는 바이다.

• Journal of Preventive Medicine and Public Health
• /
• v.30 no.2 s.57
• /
• pp.308-326
• /
• 1997

Many studies have led to the notion that essential hypertension in adults is the result of a process that starts early in life: investigation of blood pressure(BP) in children and adolescents can therefore contribute to knowledge of the etiology of the condition. A unique longitudinal study on BP in Korea, known as Kangwha Children's Blood Pressure(KCBP) Study was initiated in 1986 to investigate changes in BP in children. This study is a part of the KCBP study. The purposes of this study are to show changes in BP and to determine factors affecting to BP level and change in Korean adolescents during age period 12 to 16 years. A total of 710 students(335 males, 375 females) who were in the first grade at junior high school(12 years old) in 1992 in Kangwha County, Korea have been followed to measure BP and related factors(anthropometric, serologic and dietary factors) annually up to 1996. A total of 562 students(242 males, 320 females) completed all five annual examinations. The main results are as follows: 1. For males, mean systolic and diastolic BP at age 12 and 16 years old were 108.7 mmHg and 118.1 mmHg(systolic), and 69.5 mmHg and 73.4 mmHg(diastolic), respectively. BP level was the highest when students were at 15 years old. For females, mean systolic and diastolic BP at age 12 and 16 years were 114.4 mmHg and 113.5 mmHg(systolic) and 75.2 mmHg and 72.1 mmHg(diastolic), respectively. BP level reached the highest point when they were 13-14 years old. 2. Anthropometric variables(height, weight and body mass index, etc) increased constantly during the study period for males. However, the rate of increase was decreased for females after age 15 years. Serum total cholesterol decreased and triglyceride increased according to age for males, but they did not show any significant trend fer females. Total fat intake increased at age 16 years compared with that at age 14 years. Compositions of carbohydrate, protein and fat among total energy intake were 66.2:12.0:19.4, 64.1:12.1:21.8 at age 14 and 16 years, respectively. 3. Most of anthropometric measures, especially, height, body mass index(BMI) and triceps skinfold thickness showed a significant correlation with BP level in both sexes. When BMI was adjusted, serum total cholesterol showed a significant negative correlation with systolic BP at age 12 years in males, but at age 14 years the direction of correlation changed to positive. In females serum total cholesterol was negatively correlated with diastolic BP at age 15 and 16 years. Triglyceride and creatinine showed positive correlation with systolic and diastolic BP in males, but they did not show any correlation in females. There was no consistent findings between nutrient intake and BP level. However, protein intake correlated positively with diastolic BP level in males. 4. Blood pressure change was positively associated with changes in BMI and serum total cholesterol in both sexes. Change in creatinine was associated with BP change positively in males and negatively in females. Students whose sodium intake was high showed higher systolic and diastolic BP in males, and students whose total fat intake was high maintained lower level of BP in females. The major determinants on BP change was BMI in both sexes.

• Physical Therapy Korea
• /
• v.7 no.4
• /
• pp.39-46
• /
• 2000

본 연구는 강직성 편측 뇌성마비 환자의 보행 기시(gait initiation)의 특성을 파악하고, 동적 단하지 보조기(dynamic ankle foot orthosis : DAFO)가 이런 환자들의 보행 기시에 미치는 영향을 알아보기 위하여 실시하였다. 연구대상자는 19세 선천성 강직성 우측 뇌성마비를 가진 여자 대학생이었다. 연구대상자는 4개의 다른 보행 기시 조건에서 각 조건당 7회의 보행 기시를 하였는데, 각각의 보행 기시 조건은: 1) 보조기 없이 좌측 하지로 보행 기시; 2) 우측 하지 보조기 착용 상태에서 좌측하지로 보행 기시; 3) 보조기 없이 우측 하지로 보행 기시; 4) 우측 하지 보조기 착용 상태에서 우측 하지로 보행 기시였다. 두개의 힘 판(force plate) 위에서 본인이 선택한 가장 편안한 방법과 속도로 2 m를 걷도록 하였다. 연구대상자가 보행 기시를 하는 동안 양쪽 가자미근과 앞정강근에 부착된 4개의 표면 전극으로부터 근 전도 신호와 보행 기시를 하는 연구 대상의 양 발 아래 놓인 두개의 힘 판의 자료를 분석하여 체중(body weight : BW)으로 정량화 하였다. 실험결과는 각 조건마다 7회 실시된 측정값들의 평균을 이용하였다. 본 사전연구의 결과는 다음과 같다. 1. 보행 기시 전 양다리로 선 상태에서 환측보다 건측으로 많은 체중지지를 하였으나(환측 42.57%BW, 건측 58.03%BW) 보조기의 착용이 환측으로의 체중지지를 향상시켰다(환측 44.46%BW, 건측 55.54%BW). 2. 보행 기시 중 가자미근과 앞정강근의 동시수축(coactivation)이 계속되었는데 이러한 양상은 보조기의 착용 유무에 따라 크게 달라지지 않았다. 3. 힘 판에서 들어온 지면 반발력(ground reaction force)의 수직 분력(vertical element, Fz)과 전후 분력(anterior-posterior element, Fx)을 분석한 결과, 건측 다리로 보행 기시를 할 때 보조기 착용은 가속을 촉진시켜 역학적으로 유리하였다. 이상의 연구 결과는 보조기의 착용이 건측 다리로 보행 기시를 할 때 미치는 신경학적, 역학적 장점들에 대한 구체적 연구의 필요성 및 근거를 제시하고, 환자들의 보행훈련 접근에 보다 효율적인 보행방법을 소개하는데 이용될 수 있다.

• Journal of Chest Surgery
• /
• v.34 no.10
• /
• pp.754-762
• /
• 2001

Background: To evaluate the efficacy of arterial switch operation for transposition of great arteries, serial echocardiographic studies were performed in 8 patients who underwent the surgery between 1989 and 1998 at Dept. of Thoracic & Cardiovascular Surgery, Yeungnam University Hospital in Daegu City, Korea. Material and Method: Follow-up period ranged from 6 months to 11 years(average of 4.1 years). Body weight ranged from 2.6kg to 4.8kg, with average of 3.6kg. 5 of 8 patients were preoperatively diagnosed as TGA+VSD, and 3 as TGA+IVS. LV function was evaluated by the measurement of LV shortening fraction, LVSTI, and LVEF. RVSTI was also measured. Postoperative function of valve and growth of great vessels were analyzed by the measurement of PSPGV, valvular regurgitation, LA/AO ratio, root dimension of aorta and pulmonary artery, comparing with the age matched controls, respectively. Result: LVEF had an average of 65.0+9.03% which is tended to increase serially. LVAOPG had an average of 15.9mmHg. RVPAPG, 27.5mmHg. From the measurement of aortic root dimension of 6 patients at end-systole, aortic root growth was assumed to increase more than the mean value of normal growth. PA root dimension at end-systole showed a similar growth progress when compared with age matched normal controls. Postoperative pulmonic valve regurgitation was noted in 5 of total 8 patients, in which 1 patient who showed grade 2 and 4 showed below grade 1. AR, in 6 patients and all grade 1 Except 1 patient, all the valvular regurgitations were below grade 1, which was presumed to be clinically insignificant.

• Tuberculosis and Respiratory Diseases
• /
• v.45 no.1
• /
• pp.99-106
• /
• 1998

Background: Bronchial asthma is a complex disease, which is characterized by spontaneous exacerbations of airway obstruction and persistent bronchial hyperresponsiveness. Animal models have fallen short of reproducing the human disease, particularly in mimicking the spontaneous and persistent airflow obstruction that characterized in asthma. In animals, airflow obstruction is usually assessed by measuring airflow resistance during tidal breathing under such invasive technique as tracheostomy and anesthesia. A noninvasive technique for measuring pulmonary function in small animals is needed to evaluate long-term changes in lung function during the course of experimentally produced disease without sacrificing the animal. Purpose: The purpose of this study was to evaluate early bronchoconstrcition after allergen challenge and airway responsiveness (AR) to inhaled methacholine in nonanethetized, unrestrained guinea pigs. Method: Guinea pig model of asthma was sensitized by subcutaneous injection with ovalbumin and challenged by inhalation of aerosolized ovalbumin(1% wt/vol ovlabumin). Airflow obstruction of conscious guinea pig was measured as specific airway resistance (airway resistance $\times$ thoracic gas volume). Airway resistance and thoracic gas volume of conscious guinea pig were assessed by body plethysmography before challenge and at regular intervals for as long as 30 minutes after challenge. AR to aerosolized methacholine of asthma group was compared with that of control group in body plethysmography. Result: Asthma model<> developed in 13 (65%) among 20 guinea pigs, in which early responses occurred in the airways after the exposure to inhalation with ovalbumin. Airway challenge with ovalbumin caused increase in specific airway resistance, which peaked at 6 minutes and amounted to a $231.5{\pm}30.4%$ increase from baseline. AR to aerosolized methacholine of asthma model increased significantly compared with control group. Conclusion: These results have showed a useful animal model to evaluate early bronchoconstrcition after allergen challenge and airway responsiveness in nonanethetized, unrestrained guinea pigs.