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An Evaluation of the Accuracy of Mini-Wright Peak Flow Meter (mini-Wright Peak Flow Meter에 의한 PEFR 측정의 정확도)

  • Koh, Young-Il;Choi, In-Seon;Na, Hyun-Ju;Park, Seok-Chae;Jang, An-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.44 no.2
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    • pp.298-308
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    • 1997
  • Background : Portable devices for measuring peak expiratory flow(PEF) are now of proved value in the diagnosis and management of asthma and many lightweight PEF meters have become available. However, it is necessary to determine whether peak expiratory flow rate(PEFR) measurements measured with peak flowmeters is accurate and reproducible for clinical application. The aim of the present study is to define accuracy, agreement, and precision of mini-Wright peak flow meter(MPFM) against standard pneumotachygraph. Methods : The lung function tests by standard pneumotachygraph and PEFR measurement by MPFM were performed in a random order for 2 hours in 22 normal and 17 asthmatic subjects and also were performed for 3 successive days in 22 normals. Results : The PEFR measured with MPFM was significantly related to the PEFR and $FEV_1$ measured with standard pneumotachygraph in normal and asthmatics(for PEFR, r = 0.92 ; p < 0.001 ; for $FEV_1$, r = 0.78 ; p < 0.001). The accuracy of MPFM was within 100(limits of accuracy recommeded by NAEP) in all the subjects or 22 normal, mean difference from standard pneumotachygraph being 16.5L/min(percentage of difference being 2.90%) or 10.6L/min(percentage of difference being 1.75%), respectively. According to the method proposed by Bland and Altman, the 95% limits of the distribution of differences between MPFM and standard pneumotachygraph after correction of PEFR using our regression equation were +38.2 and -71.5L/min in all the subjects or 20.49~+9.49L/min in 22 normal and was similar to the intraindividual agreements for 3 successive days in normal. There was no statistically significant difference of PEFR measured with MPFM and standard pneumotachygraph among three days(p > 0.05) and the coefficient of variation($2.4{\pm}1.2%$) of PEFR measured with MPFM was significantly lower than that($5.2{\pm}3.5%$) with standard pneumotachygraph in normal (p < 0.05). Conclusion : This results suggest that the MPFM was as accurate and reproducible as standard pneumotachygraph for monitoring of PEFR in the asthmatic subjects.

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Throughfall, Stemflow and Interception Loss of the Natural Old-growth Deciduous and Planted Young Coniferous in Gwangneung and the Rehabilitated Young Mixed Forest in Yangju, Gyeonggido(I) - with a Special Reference on the Results of Measurement - (광릉(光陵) 활엽수(闊葉樹) 천연노령림(天然老齡林)과 침엽수(針葉樹) 인공유령림(人工幼齡林) 그리고 양주(楊洲) 사방지(砂防地) 혼효유령림(混淆幼齡林)의 수관통과우량(樹冠通過雨量), 수간유하량(樹幹流下量) 그리고 차단손실량(遮斷損失量)에 관하여(I) - 실험적(實驗的) 측정결과(測定結果)를 중심(中心)으로 -)

  • Kim, Kyongha;Jun, Jaehong;Yoo, Jaeyun;Jeong, Yongho
    • Journal of Korean Society of Forest Science
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    • v.94 no.6
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    • pp.488-495
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    • 2005
  • This study was conducted to understand the influences of forest structure on throughfall, stemflow and interception loss. The study plots included the natural old-growth deciduous, Pinus koraiensis and Abies holophylla forests in Gwangneung and the rehabilitated young mixed forest in Yangju, Gyeonggido. The Pinus koraiensis and Abies hotophylla had been planted in 1976. The rehabilitated young mixed forest had been established to control erosion in 1974. Total and net rainfall were monitored from March, 2003 to October, 2004. Tipping bucket rain gauge recorded total rainfall. Throughfall and stemflow were measured by custom-made tipping bucket and CR10X data logger at each $10m{\times}10m$ plots at intervals of 30 minutes. Interception loss in the Pinus koraiensis plot were most as 37.2% of total rainfall and least as 22.6% in the rehabilitated young mixed forest. Stemflow in the rehabilitated young mixed forest was 10.7% of total rainfall and stemflow in the Pinus koraiensis plot was 2.4%. The average throughfall ratio ranged from 66% to 77% depending on the canopy coverage. The relationship of stemflow and total rainfall represented in a linear regression equation though the variation of data was large. The ratio of stemflow-conversion was 2% of total rainfall in the Pinus koraiensis plot and 12% in the rehabilitated young mixed forest, respectively. The stem storage of the natural old-growth deciduous was the largest of 0.21 mm whereas that of the Pinus koraiensis plot was the least of 0.003 mm. A deciduous forest produced stemflow more than a coniferous forest due to a smooth bark and steeply angled branches. Interception loss of all study plots increased linearly as total rainfall increased. The distribution of interception loss data related in total rainfall became wider in a deciduous forest than a coniferous. It resulted from seasonality of leaf area index in a deciduous forest. As considered above results, it was confirmed that there were great differences of throughfall, stemflow and interception loss depending on forest stand structures. The simulation model for predicting interception loss must have parameters such as forest stand characteristics and LAI in order to describe the influence of forest structure on interception loss.

Experimental and clinical studies with impedance audiometry; the increase in air volume in the middle ear air system and the pneumatization of human temporal bones (측두골의 함기도와 중이강의 용적이 고막 임피던스에 미치는 영향에 관한 연구)

  • 민양기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1977.06a
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    • pp.4.4-5
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    • 1977
  • The vibratory energy introduced into the external ear canal is changed by the mechanical factors of eardrum itself, the motility of ossicles, and the air cushion of tympanic cavity and the like. This study was designed to investigate the volume of middle ear cavity and mastoid air cell system as a factor of determining the accoustic impedance of middle ear system. The author studied how the increase in air volume of middle ear cavity effects on the acoustic impedance of middle ear system with dogs' ears and researched the correlation between the degree of pneumatization of temporal bones and the acoustic impedance of middle ear system by comparing the radiological findings of pneumatization (Law's and Towne's projection) with the acoustic impedance measurements with Madsen ZO 70. The result is as follows: 1 The tympanometric findings in control state revealed the curves of type A, and did not change in its configuration by the increase in the air volume of dogs middle ear system. 2. The static compliance of middle ear revealed a distinct and linear increase in proportion to the increase in air volume of middle ear system; the rate of increase was $0.05{\pm}0.02$ cc of static compliance per cc of air volume. 3. Authenticated in the above result and the tendency to increase in static compliance in proportion to the increase in the degree of pneumatization of temporal bones, there was significant regression equation between the degree of pneumatization of temporal bones (x variable) and the static compliance of middle ear system; $y=0.19x{\pm}0.16{\pm}0.05$ It is suggested that the difference in volume of middle ear system plays an important role in the change of the static compliance of middle ear, and the author concludes that the measurement of static compliance of middle ear has clinical value as diagnostic means of evaluating the degree of pneumatization of temporal bones along with some radiological examination.

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The Effects of Self-Congruity and Functional Congruity on e-WOM: The Moderating Role of Self-Construal in Tourism (중국 관광객의 온라인 구전에 대한 자아일치성과 기능일치성의 효과: 자기해석의 조절효과를 중심으로)

  • Yang, Qin;Lee, Young-Chan
    • The Journal of Information Systems
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    • v.25 no.1
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    • pp.1-23
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    • 2016
  • Purpose Self-congruity deals with the effect of symbolic value-expressive attributes on consumer decision and behavior, which is the theoretical foundation of the "non-utilitarian destination positioning". Functional congruity refers to utilitarian evaluation of a product or service by consumers. In addition, recent years, social network services, especially mobile social network services have created many opportunities for e-WOM communication that enables consumers to share personal consumption related information anywhere at any time. Moreover, self-construal is a hot and popular topic that has been discussed in the field of modem psychology as well as in marketing area. This study aims to examine the moderating effect of self-construal on the relationship between self-congruity, functional congruity and tourists' positive electronic word of mouth (e-WOM). Design/methodology/approach In order to verify the hypotheses, we developed a questionnaire with 32 survey items. We measured all the items on a five-point Likert-type scale. We used Sojump.com to collect questionnaire and gathered 218 responses from whom have visited Korea before. After a pilot test, we analyzed the main survey data by using SPSS 20.0 and AMOS 18.0, and employed structural equation modeling to test the hypotheses. We first estimated the measurement model for its overall fit, reliability and validity through a confirmatory factor analysis and used common method bias test to make sure that whether measures are affected by common-method variance. Then we tested the hypotheses through the structural model and used regression analysis to measure moderating effect of self-construal. Findings The results reveal that the effect of self-congruity on tourists' positive e-WOM is stronger for tourists with an independent self-construal compared with those with interdependent self-construal. Moreover, it shows that the effect of functional congruity on tourists' positive e-WOM becomes salient when tourists' self-construal is primed to be interdependent rather than independent. We expect that the results of this study can provide important implications for academic and practical perspective.

SOFT TISSUE PROFILE CHANGE PREDICTION IN MAXILLARY INCISOR RETRACTION BASED ON CEPHALOMETRICS (두부방사선 분석에 의한 상악전치부 후방이동시 연조직 변화 예측에 대한 연구)

  • Choi, Jin-Hee;Lee, Jin-Woo;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.27 no.1
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    • pp.65-78
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    • 1997
  • This study was carried out in order to determine soft tissue response to incisor movement and mandibular repositioning and to determine feasibility of predicting vertical and horizontal changes in soft tissue with hard tissue movement. For this study, cephalometric records of 41 orthodontically treated adult females who had Angle's Class II division 1 malocclusion were selected and stepwise multiple regression analysis was employed. Following conclusions were obtained by analysing the changes of soft tissue and hard tissue before and after treatment. 1. Hard tissue measurements that showed significant changes before and after treatment were horizontal and angular changes of maxillary incisor, horizontal,vertical and angular changes of mandibular incisor, overjet, overbite, interincisal angle, mandibular repositioning, A,B, skeletal convexity and soft tissue measurements that showed significant changes were horizontal, thickness and angular changes of upper lip, horizontal and angular changes of lower lip, interlabial angle, nasolabial angle labiomental angle, Sri, Ss, Si and soft tissue convexity(P<0.05). 2. All Soft tissue measurements changed significantly before and after treatment had between one and four hard tissue independent variables at statistically significant level, indicating that all soft tissue changes were direct relationship with hard tissue changes 3. Ova jet, horizontal change of maxillary incisor, horizontal change of maxillary root apex and horizontal change of pogonion entered into prediction equations most frequentely indicating that they were more significant variables in prediction of vertical and horizontal changes in the soft tissue with treatment, but vertical changes of mandibular incisor not entered any prediction equations, indicating that it was not considered a good predictor for soft tissue changes with maxillary incisor retraction. 4. Horizontal and vertical changes in subnasale were found to have most independent variables, significant at the 0.05 level in prediction-equations(${\Delta}$Sn(H):Ur, Is(H), Pg(H), UIA,${\Delta}$Sn(V): Is(H), Pg(H), overjet, A), indicating that subnasale changes are influenced by complex hard tissue interaction. 5. Multiple correlation coefficient($R^2$) of the soft tissue prediction equations ranges from 0.2-0.6.

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The Normal Predicted Value of Peak Expiratory Flow(PEF) Measured by the Peak Flow Meter and Correlation Between PEF and Other Ventilatory Parameters (Peak Flow Meter로 측정한 최대호기류속도(PEF)의 추정정상치 및 가타 환기기능검사와의 상관관계)

  • Kim, Min-Chul;Kwon, Kee-Buem;Yim, Dong-Hyun;Song, Chang-Seuk;Jung, Yong-Seuk;Jang, Tae-Won;Yeu, Ho-Dae;Jung, Maan-Hong
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.5
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    • pp.1000-1011
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    • 1998
  • Background: For the diagnosis or evaluation of airway obstruction in bronchial asthma and chronic obstructive lung disorders, various parameters derived from the forced expiratory volume curve and maximal expiratory flow volume curve have been used. Recently the peak expiratory flow(PEF) measured by the peak flow meter is widely used because of its simplicity and convenience. But there were still no data of the predicted normal values measured by the peak flow meter in Korea. This study was to obtain the predicted normal value of PEF and to know the accuracy of this value to predict $FEV_1$. Method: The measurements of PEF by the MiniWright peak flow meter and several parameters derived from the forced expiratory volume and maximal expiratory flow volume curves by the Microspiro HI 501(Chest Co.) were done in 129 men and 125 women without previous history of the respiratory diseases. The predicted normal values of parameters according to the age and the height were obtained, and the regression equation of $FEV_1$ by PEF was calculated. Results: The predicted normal values of PEF(L/min) were -2.45$\times$Age(year) +1.36 $\times$ Height(cm)+427 in men, and -0.96 $\times$ Age (year) + 2.01 $\times$ Height (cm) + 129 in women. FEFmax derived from the maximal expiratory flow volume curve was less than by 125 L/min in men and 118 L/min in women respectively compared to PEF. $FEV_1$(ml) predicted by PEF was 5.98 $\times$ PEF(L/min) + 303 in men, and 4.61 $\times$ PEF(L/min) + 291 in women respectively. Conclusion : The predicted normal value of PEF measured by the peak flow meter was calculated and it could be used as a standard value of PEF while taking care of patients with airway obstruction. $FEV_1$, the gold standard of ventilatory function, could be predicted by PEF to a certain extent.

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A Study on the Determination of the Maintenance Energy Requirement in Growing Goats (육성기 염소의 유지에너지 요구량 결정연구)

  • Chung, Sang Uk;Zhang, Qi-Man;Jang, Se Young;Yun, Yeong Sik;Moon, Sang Ho
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.40 no.2
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    • pp.111-116
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    • 2020
  • This study was conducted to determine the maintenance energy requirements of growing goats in order to establish an appropriate energy benefit system, to reduce feed costs and improve livestock productivity of goat farmers, and to present basic data for detailed specifications afterwards. This experiment was conducted as a group specification test for a total of 3 months, with 32 goats of three months age and conducted by four treatments with different energy levels (T1: NRC+0%, T2: NRC+10%, T3: NRC+20%, and T4: NRC+30%). The average daily gain was the highest in the treated with NRC + 10% of the energy level of the experimental diet, and the feed conversion ratio was in the range of 6.3 g to 7.3 g in the group feeding experiment. Although there was no significant difference in digestibility between treatments, the digestibility of dry matter, crude protein, and crude fat was higher in T2 treated with NRC + 10% than the other treatments. Through the regression equation of the values of MEI and ADG obtained through the experiment (Y=0.5439X+111.51, R2=0.712), the maintenance energy requirement of the goat in the growing period was estimated to be 111.51 kcal/kgBW0.75.

Population Phenology and an Early Season Adult Emergence model of Pumpkin Fruit Fly, Bactrocera depressa (Diptera: Tephritidae) (호박과실파리 발생생태 및 계절초기 성충우화시기 예찰 모형)

  • Kang, Taek-Jun;Jeon, Heung-Yong;Kim, Hyeong-Hwan;Yang, Chang-Yeol;Kim, Dong-Soon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.10 no.4
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    • pp.158-166
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    • 2008
  • The pumpkin fruit fly, Bactrocera depressa (Tephritidae: Diptera), is one of the most important pests in Cucurbitaceae plants. This study was conducted to investigate the basic ecology of B. depressa, and to develop a forecasting model for predicting the time of adult emergence in early season. In green pumpkin producing farms, the oviposition punctures caused by the oviposition of B. depressa occurred first between mid- and late July, peaked in late August, and then decreased in mid-September followed by disappearance of the symptoms in late September, during which oviposition activity of B. depressa is considered active. In full-ripened pumpkin producing farms, damaged fruits abruptly increased from early Auguest, because the decay of pumpkins caused by larval development began from that time. B. depressa produced a mean oviposition puncture of 2.2 per fruit and total 28.8-29.8 eggs per fruit. Adult emergence from overwintering pupae, which was monitored using a ground emergence trap, was first observed between mid- and late May, and peaked during late May to early June. The development times from overwintering pupae to adult emergence decreased with increasing temperature: 59.0 days at $15^{\circ}C$, 39.3 days at $20^{\circ}C$, 25.8 days at$25^{\circ}C$ and 21.4 days at $30^{\circ}C$. The pupae did not develop to adult at $35^{\circ}C$. The lower developmental threshold temperature was calculated as $6.8^{\circ}C$ by linear regression. The thermal constant was 482.3 degree-days. The non-linear model of Gaussian equation well explained the relationship between the development rate and temperature. The Weibull function provided a good fit for the distribution of development times of overwintering pupae. The predicted date of 50% adult emergence by a degree-day model showed one day deviation from the observed actual date. Also, the output estimated by rate summation model, which was consisted of the developmental model and the Weibull function, well pursued the actual pattern of cumulative frequency curve of B. depressa adult emergence. Consequently, it is expected that the present results could be used to establish the management strategy of B. depressa.

Effects of Different Nitrogen Levels and Planting Densities on the Quality and Yield of the Black Rice Cultivar 'Shinnongheugchal' (재식밀도 및 시비량 차이가 신농흑찰 품질 및 수량에 미치는 영향)

  • Lee, In-Sok;Lee, Deok-Ryeol;Cho, Seung-Hyun;Lee, Song-Yi;Kim, Kab-Cheol;Lee, Ki-Kwon;Song, Young-Ju
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.61 no.2
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    • pp.79-86
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    • 2016
  • The late-maturing black rice cultivar Shinnongheugchal from Jeollabuk-do Agricultural Research and Extension Service was used as the plant material for estimating growth characters, quality and yield from the vegetation period to harvest age. This study was performed to select an optimum combination of nitrogen level and planting density for the maximum yield of Shinnongheugchal. The plant height, number of tillers, and SPAD index were higher when the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level was used at 30 days after transplanting. The heading date for the combination of 70 hills per $3.3m^2$ and 15 kg/10 a nitrogen level, and 80 hills per $3.3m^2$ and 15 kg/10 a nitrogen level was August 22. The heading date for the other combinations was August 21. The combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level yielded the highest number of tillers at 40 days after flowering. Even though the lodging index was increased with increasing nitrogen levels, field lodging did not occur until harvest time. Seed nitrogen concentration in the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level showed a significant difference when compared with the other combinations. The black rice yield varied significantly, and the highest yield was observed in the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level. The yield was significantly correlated with seed nitrogen concentration. The maximum yield was estimated to be 14.67 kg/10 a nitrogen level by using the regression equation. On average, the coloring degree of the black rice was higher at planting density of 70 hills per $3.3m^2$ than at 80 hills per $3.3m^2$. The highest yield of perfect black rice was obtained using the combination of 70 hills per $3.3m^2$ and 13 kg/10 a nitrogen level. Our findings demonstrate that a nitrogen level of 13-14 kg/10 a can be used to obtain the maximum yield from Shinnongheugchal with yield, cyanidin 3-glucoside content, and perfect black rice yield as the standard.

Determination of Energy Requirements for Maintenance in Hanwoo Steers (거세한우의 유지에너지 요구량 결정)

  • Kim, K.H.;Oh, Y.G.;Kim, W.;Lee, S.C.;Shin, K.J.;Jeon, B.T.
    • Journal of Animal Science and Technology
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    • v.46 no.2
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    • pp.193-200
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    • 2004
  • This experiment was carried out to determine energy requirements for maintenance of Hanwoo steers. Nine Hanwoo steers weighing 376.6$\pm$12.5kg were used in this experiment and fed rice straw(44%) and concentrate (56%) at three different energy levels; 0.8 times maintenance(0.8M), 1.2 times(1.2M) and 1.6 times(1.6M), respectively. Dry matter intake was 48.5, 65.9 and 86.5g/$BW^{0.75}$ for 0.8M, 1.2M and 1.6M, respectively. Increase in energy intake with the increased DM intake did not affect digestibilities of dry matter, organic matter, crude protein, crude fiber, crude fat and nitrogen-free extract. Gross energy intake averaged 190.8, 255.8 and 340.9kcal/BW0.75 for 0.8M, 1.2M and 1.6M, respectively. Energy loss was 41% feces and 0.6${\sim}$1.5% urine of gross energy intake. Further, energy loss from methane produced during rumen fermentation was 5${\sim}$9%, while body heat loss averaged 40${\sim}$60%. Intercept of the regression equation between ME intake and retained energy indicated that energy requirement for maintenance was 124.3kcal $ME/BW^{0.75}$.