• 한국환경보건학회지
• /
• 제47권5호
• /
• pp.425-431
• /
• 2021

Background: This study evaluated the radon contribution rate through an evaluation of the exhalation rate of radon from building materials. Objectives: This study compared and evaluated the computation of the radon contribution rate based on each different exhalation rate in a building. Methods: The six demonstration houses that are the subject of this study are wall structures or Rahmen structures, and include demonstration houses similar to general residential environments and non-finishing houses with some walls exposed. Results: The highest exhalation rate was found at 62.98 Bq/m² per day from the non-finishing floor, and the second highest exhalation rate was from stone materials at 58.76 Bq/m² per day. Based on this result, investigating the contribution rate of building materials derived from building materials among indoor radon concentrations, house three was the highest at 81.7%, and house one was confirmed to be 33.96%. Conclusions: It can be judged that the effect of exposed concrete and stone is high, and that it is possible to reduce radon emitted from indoor building structures by controlling the indoor materials.

• Journal of Advanced Marine Engineering and Technology
• /
• 제40권9호
• /
• pp.842-846
• /
• 2016

물속의 용존산소를 이용하면 물고기가 아가미를 이용하여 호흡하듯이 사람이 수중에서 호흡이 가능하지만, 물속에 포함된 용존산소의 양이 적기 때문에 필요한 산소량을 확보하는 문제가 해결되어야 한다. 우선 물의 유량을 증가시켜 분리되는 산소량을 증가하는 것이 가능하지만, 필요한 펌프와 멤브레인 그리고 주변기기의 용량 증가로 분리장치의 부피와 무게 그리고 소요비용도 함께 증가하게 된다. 이러한 문제를 효과적으로 해결하기 위해 많은 양의 산소를 포함하는 날숨의 특성을 이용하면 필요한 산소량을 효과적으로 확보할 수 있다. 일반적으로 날숨에 포함된 산소량은 공기보다 낮고, 이산화탄소 량은 공기보다 많은 것으로 알려져 있다. 본 연구에서는 용존기체 분리장치의 입력 단에 날숨을 혼합한 후, 용존기체 분리장치에서 산소를 포함하는 용존기체를 재분리하는 과정을 거치며, 이때, 입력단에 설치된 수중펌프의 동작으로 수압이 증가하므로, 이러한 수압을 갖는 물에 날숨을 혼합하기 위해서는 압축기가 요구되므로 분리장치의 무게와 부피 그리고 소비 전력이 증가하게 된다. 본 연구에서는 입력단의 압력을 감소시킴으로써 압축기를 사용하지 않고도 날숨을 물에 혼합하는 구조를 갖는 것이 특징이다. 실험을 통해 압축기를 사용하지 않고 날숨이 입력단의 물에 혼합되는 것이 가능함을 제시하였으며, 날숨이 입력단에 공급된 후 분리장치를 통해 분리된 기체의 분리특성을 제시하였다. 날숨을 사용함으로써 용존기체의 분리량이 크게 증가하였으며, 공급되는 날숨의 유량이 증가하면 분리되는 용존 기체의 양도 증가하였다.

• Journal of Radiation Protection and Research
• /
• 제43권1호
• /
• pp.29-38
• /
• 2018

Background: Radon contributing about 42% of annual average dose, mainly comes from soil. In this paper, standard measurement procedures for soil radon exhalation rate are suggested and their measurement uncertainties are analyzed. Materials and Methods: We used accumulation method for estimating surface exhalation rate. The closed-loop measurement system was made up with a RAD7 detector and a surface chamber. Radon activity concentrations in the system were observed as a function of time, with data collection of 5 and 15-minute and the measurement time of 4 hours. Linear and exponential fittings were used to obtain radon exhalation rates from observed data. Standard deviations of measurement uncertainties for two approaches were estimated using usual propagation rules. Results and Discussion: The exhalation rates (E) from linear approach, with 30 minutes measurement time were $44.8-48.6mBq{\cdot}m^{-2} {\cdot}s^{-1}$ or $2.14-2.32atom{\cdot}cm^{-2}{\cdot}s^{-1}$ with relative measurement uncertainty of about 10%. The contributions of fitting parameter A, volume (V) and surface (S) to the estimated measurement uncertainty of E were 59.8%, 30.1% and 10.1%, in average respectively. In exponential fitting, at 3-hour measurement we had E ranged of $51.6-69.2mBq{\cdot}m^{-2} {\cdot}s^{-1}$ or $2.46-3.30atom{\cdot}cm^{-2}{\cdot}s^{-1}$ with about 15% relative uncertainty. Fitting with 4-hour measurement resulted E about $51.3-68.2mBq{\cdot}m^{-2} {\cdot}s^{-1}$ or $2.45-3.25atom{\cdot}cm^{-2}{\cdot}s^{-1}$ with 10% relative uncertainty. The uncertainty contributions in exponential approach were 75.1%, 13.4%, 8.7%, and 2.9% for total decay constant k, fitting parameter B, V, and S, respectively. Conclusion: In obtaining exhalation rates, the linear approach is easy to apply, but by saturation feature of radon concentrations, the slope tends to decrease away from the expected slope for extended measurement time. For linear approach, measurement time of 1-hour or less was suggested. For exponential approach, the obtained exhalation rates showed similar values for any measurement time, but measurement time of 3-hour or more was suggested for about 10% relative uncertainty.

• 대한간호학회지
• /
• 제46권4호
• /
• pp.514-522
• /
• 2016

Purpose: The purpose of this study was to identify the effects of exhalation breathing exercises using expirometer and that of inhalation breathing exercises using incentive spirometry on pulmonary function and complications in elderly patients with upper-abdominal surgery. Methods: The research design was a nonequivalent control group non-synchronized design. Participants were 63 patients who underwent upper-abdominal surgery under general anesthesia (32 in experiment group, 31 in control group). They were recruited at P university hospital from August 1 to November 30, 2015. Effects were evaluated by measuring pulmonary functions (Forced Vital Capacity [FVC], Forced Expiratory Volume in 1 second [FEV1]) and pulmonary complications. Data were analyzed using SPSS/WIN 18.0 program. Results: There was no difference in FVC between the experimental group and the control group, but FEV1 in the experimental group increased significantly compared to the control group by time change (p=.001). Also, there were no pulmonary complications in the experimental group but there were 5 cases (16.1%)(p=.018) in the control group. Conclusion: Findings indicate that exhalation breathing exercises by elderly patients following upper-abdominal surgery is an effective nursing intervention in enhancing pulmonary function and preventing pulmonary complications.

• PNF and Movement
• /
• 제18권2호
• /
• pp.297-303
• /
• 2020

Purpose: The purpose of this study was to examine the effects of inhalation and exhalation exercise combined with upper extremity proprioceptive neuromuscular facilitation pattern on two spirometry values: forced volume vital (FVC) and peak expiratory flow (PEF). Methods: Thirty-two healthy adults were divided into two groups: 1) a combined group, which performed upper extremity D2 flexion pattern (shoulder flexed/abducted/external rotated, forearm supinated, wrist radial deviated, and finger extended) during exhalation and D2 extension pattern (shoulder extended/adducted/internal rotated, forearm pronated, wrist ulnar deviated, and finger flexed) during inhalation; and 2) reverse combined group, which performed the D2 flexion pattern during inhalation and the D2 extension pattern during exhalation. The inverse application of upper extremity movements during inhalation and exhalation induced selective resistance or assistance on respiration. FVC and PEF were measured at two time points, before and after four weeks. Results: In both groups, the pre-post intervention comparison showed significant increases in FVC and PEF (p < .05). In the between-groups comparison, the reverse combined group showed a significantly higher PEF than the combined group at four weeks post intervention (p < 0.05). Conclusion: The combined respiration exercise with reverse PNF upper extremity patterns using selective resistance showed an effective increase in PEF in healthy adults. Clinicians and researchers might consider using selective resistance as a widely applicable and cost-effective option for respiratory rehabilitation planning.

• 한국전문물리치료학회지
• /
• 제21권2호
• /
• pp.1-7
• /
• 2014

Lumbopelvic stabilization exercise has become the most popular treatment method in lumbar rehabilitation since its effectiveness was shown in some aspects of pain and disability. The abdominal drawing-in maneuver (ADIM) has been extensively implemented to promote lumbopelvic stability. However, performing ADIM correctly is difficult even for healthy subjects, and it is time consuming to train people in ADIM. Thus, the purpose of this study was to compare abdominal muscle [rectus abdominalis (RA), external oblique (EO), and transverse abdominis/internal oblique (TrA/IO)] activity during lumbopelvic stabilization exercises (ADIM only, ADIM with a ball, maximum exhalation only, and maximum exhalation with a ball) performed in a supine position with feet against a wall. Fifteen healthy subjects were recruited for this study. Surface electromyography was used to measure abdominal muscle activity during lumbopelvic stabilization exercises. A one-way repeated-measures analysis of variance was used to determine the statistical significance of RA, EO, and TrA/IO muscle activity during four lumbopelvic stabilization exercises. Both-side TrA/IO muscle activity was significantly greater with maximum exhalation with a ball than with ADIM only or ADIM with a ball (p<.008). The results of this study suggest that maximum exhalation with a ball can be used as an effective lumbopelvic stabilization exercise to increase TrA/IO muscle activity in healthy subjects.

• Journal of Radiation Protection and Research
• /
• 제16권1호
• /
• pp.15-24
• /
• 1991

CR-39 플라스틱 핵비적검출기를 라돈검출기로 내장한 멤브레인 필터컵(일명 : CR-39 라돈컵)을 이용하여 일부 국산건축자재의 라돈방출율을 측정하였다. 표준라듐선원을 이용한 라돈컵의 교정 실험을 수행하여 얻은 CR-39 검출기의 라돈검출인자는 $0.164{\pm}0.005(tracks \;cm^{-2}/Bq\;d\;m^{-3})$였으며 타 연구자들의 발표결과와 잘 일치하였다. 일부 건축자재(모래벽돌, 적벽돌, 화장석판, 콘크리트 덩어리, 건물바닥과 내벽)에 CR-39 라돈컵을 2개월 동안 기밀 부착하여 라돈방출율을 측정한 결과, 라돈방출율은 모래벽돌에서 평균$(75.0{\pm}5.5){\times}10^{-6}(Bq/m^2-s)$, 화강석판에서 $(6.8{\pm}2.9){\times}10^{-6}Bq/m^2-s)$로 10배정도의 차이를 보였으며, 모래벽돌>콘크리트바닥>콘크리트덩어리>건물벽>적벽돌>화강석 판의 순서를 보였다. 본 연구 결과, CR-39 라돈컵에 의해서도 건축자재의 라돈방출율을 효과적으로 측정할 수 있음이 입증하였다.

• 한국전문물리치료학회지
• /
• 제17권1호
• /
• pp.9-16
• /
• 2010

This study aimed to compare 2 protocols recommended to patients with chronic cervical cord injury: each protocol included breathing exercises (inhalation-oriented or exhalation-oriented) and facilitation maneuver for the accessory respiratory muscles. Seventeen patients with chronic cervical cord injury volunteered to participate in this study, and we randomized these patients into 2 groups: the inhalation-oriented breathing exercise group (IOBEG) and exhalation-oriented breathing exercise group (EOBEG), consisting of 8 and 9 patients, respectively. Patients in the IOBEG performed inspiratory exercises using intermittent positive pressure breathing devices, while those in the EOBEG performed expiratory exercises using incentive spirometry. All exercises were performed by the subjects twice a day for 4 weeks, with each session lasting an average of 20 min. The outcomes were assessed on the basis of the pre- and post-treatment values of vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and FEV1/FVC. In the IOBEG, no significant differences were observed between the pre- and post-treatment values of any of the measured variables (p>.05); however, in the EOBEG, significant improvement was noted in the VC, FVC, FEV1 measured (p<.05) after the treatment. In addition, the rates of change in the values of VC, FVC, and FEV1 differed significantly between the 2 groups (p<.05). These findings suggest that the EOBEs can enhance respiratory function and are clinically feasible in patients with chronic cervical cord injury. Further studies will be undertaken to evaluate the clinical application of these findings.

• Nuclear Engineering and Technology
• /
• 제52권10호
• /
• pp.2370-2378
• /
• 2020

Building materials contribute significantly to the indoor radon and thoron levels. Therefore, parameters that influence the exhalation rates of radon and thoron from building material need to be analyzed closely. As a preliminary study, the effects of humidity on exhalation rates were measured using a system with an accumulation chamber and RAD7 detector for Korean brick, Korean soil, and Indonesian brick. Resulting doses to a person who resides in a room constructed from the building materials were assessed by UNSCEAR method for different air exchange rates. The measurements have revealed that Korean brick exhaled the highest radon and thoron while Indonesian brick exhaled the lowest thoron. Results showed that for a typical low dense material, radon and thoron exhalation rate will increase until reached its maximum at a certain value of humidity and will remain saturated above it. Analysis on concentration and effective dose showed that radon is strongly affected by air exchange rate (ACH). This is showed by about 66 times decrease of radon dose from 0.00 h^-1 to those of 0.50 h^-1 ACH and decrease by a factor of 2 from 0.50 h^-1 to those of 0.80 h^-1. In case of thoron, the ACH doesn't have significant effects on effective dose.

• 지역사회간호학회지
• /
• 제22권2호
• /
• pp.121-130
• /
• 2011

Purpose: The purpose of this study is to understand the effects of a program to improve self-esteem and smoking cessation self-efficiency on smoking high school students' self-esteem, smoking cessation self-efficiency, amount of smoking, cotinine in urine, and carbon monoxide while exhalation. Methods: This research was conducted as a quasi-experimental pretest and posttest control and experimental group methodological comparison study. The subjects were 45 smoking high school students (Exp.=22, Cont.=23) in U City. Data were collected from October 19 to December 7, 2010, and analyzed using the SPSS/WIN 12.0 program by frequency, Mann-Whitney test, means, standard deviations, and Willcoxon signed rank test. Results: After the treatment, those belonging to the experimental group showed significantly increased self-esteem and smoking cessation self-efficacy and also showed decreased amount of smoking, cotinine in urine, and carbon monoxide while exhalation compared to the control group. Conclusion: The self-esteem and smoking cessation self-efficacy improvement program was effective in improving self-esteem and smoking cessation self-efficacy and in diminishing the amount of smoking, cotinine in urine and carbon monoxide while exhalation. Therefore, this program is recommended as a smoking cessation strategy for smoking adolescents.