• Title/Summary/Keyword: Beta distribution

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A Model for Supporting Information Security Investment Decision-Making Considering the Efficacy of Countermeasures (정보보호 대책의 효과성을 고려한 정보보호 투자 의사결정 지원 모형)

  • Byeongjo Park;Tae-Sung Kim
    • Information Systems Review
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    • v.25 no.4
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    • pp.27-45
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    • 2023
  • The importance of information security has grown alongside the development of information and communication technology. However, companies struggle to select suitable countermeasures within their limited budgets. Sönmez and Kılıç (2021) proposed a model using AHP and mixed integer programming to determine the optimal investment combination for mitigating information security breaches. However, their model had limitations: 1) a lack of objective measurement for countermeasure efficacy against security threats, 2) unrealistic scenarios where risk reduction surpassed pre-investment levels, and 3) cost duplication when using a single countermeasure for multiple threats. This paper enhances the model by objectively quantifying countermeasure efficacy using the beta probability distribution. It also resolves unrealistic scenarios and the issue of duplicating investments for a single countermeasure. An empirical analysis was conducted on domestic SMEs to determine investment budgets and risk levels. The improved model outperformed Sönmez and Kılıç's (2021) optimization model. By employing the proposed effectiveness measurement approach, difficulty to evaluate countermeasures can be quantified. Utilizing the improved optimization model allows for deriving an optimal investment portfolio for each countermeasure within a fixed budget, considering information security costs, quantities, and effectiveness. This aids in securing the information security budget and effectively addressing information security threats.

Distributions of 137Cs and 90Sr in the Soil of Uljin, South Korea (울진토양에서의 137Cs 및 90Sr 분포)

  • Song, JiYeon;Kim, Wan;Maeng, Seongjin;Lee, Sang Hoon
    • Journal of Radiation Protection and Research
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    • v.41 no.1
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    • pp.49-55
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    • 2016
  • Background: For the purpose of baseline data collection and enhancement of environmental monitoring the distribution studies of $^{137}Cs$ and $^{90}Sr$ in the soil of Uljin province was performed and the relation between surface soil activities and soil properties (pH, TOC and median of the surface soil) was analyzed. Materials and Methods: For 14 spots within 10 km from the NPP surface soil samples were collected and soils for depth profile were sampled for 3 spots in April 2011. Using ${\gamma}$-ray spectrometry with HPGe detector, the concentrations of $^{137}Cs$ were determined and the concentrations of $^{90}Sr$ were measured by counting ${\beta}$-activity of $^{90}Y$ (in equilibrium with $^{90}Sr$) in a gas flow proportional counter. Results and Discussion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ were $<0.479-39.6Bq{\cdot}(kg-dry)^{-1}$ (avg. $7.51Bq{\cdot}(kg-dry)^{-1}$) and $0.209-1.85Bq{\cdot}(kg-dry)^{-1}$ (avg. $0.74Bq{\cdot}(kg-dry)^{-1}$) which were similar to the reported values from other regions in Korea. The activity ratio of $^{137}Cs$ to $^{90}Sr$ in surface soils was around 9.67, which is much bigger than the initial value of 1.75 for worldwide fallouts because of faster downward movement of $^{90}Sr$ after fallout than that of $^{137}Cs$. For depth profile studies soils were collected down to 40 cm depth for the locations of Deokgu, Hujeong and Maehwa. The $^{137}Cs$ concentration distribution of the first two showed maximum values at top soils and decreased rapidly in exponential manner, while $^{90}Sr$ showed two local maximum values for soils near top and about 30 cm depth. Through linear fittings between the $^{137}Cs$ and $^{90}Sr$ concentrations of surface soil and pH, TOC and median of the surface soil, the only probable relationship obtained was between $^{137}Cs$ and TOC (determination coefficient $R^2=0.6$). Conclusion: The concentration ranges of $^{137}Cs$ and $^{90}Sr$ in Uljin were similar to the reported values from other regions in Korea. The only probable relationship obtained between activities and soil properties was between $^{137}Cs$ and TOC.

Pharmacokinetic Study of Pyrazinamide Related to the Mechanism of the Renal Excretion (Pyrazinamide의 신배설기전에 관한 약동학적 연구)

  • Choi, Eung-Sang;Shin, Sang-Goo;Lee, Sun-Hee;Choi, Cheol-Hee;Kim, Yong-Sik;Lim, Jung-Kyoo;Park, Chan-Woong
    • The Korean Journal of Pharmacology
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    • v.23 no.1
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    • pp.1-7
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    • 1987
  • The renal handling and tissue distribution of pyrazinamide were studied after administration of single dose intravenous injection for 15 min or constant infusion in New Zealand White rabbits. Peak pyrazinamide serum concentration ranged from 57.3 to $105.0{\mu}g/ml$ ($mean{\pm}SD;83.0{\pm}17.8$). The mean half-life of the a phase was $0.143{\pm}0.047$ hr while the ${\beta}$ phase ranged from 1.66 to 3.25 hr($mean{\pm}SD;2.38{\pm}0.57$). The mean steady-state volume of distribution in non-compartmental model was $0.935{\pm}0.362\;L/kg$ Excretion ratio of pyrazinamide was dramatically reduced from 1.02 to 0.30 when unbound serum pyrazinamide concentration was increased from 6.04 to $60.9\;{\mu}g/ml$. The urine flow dependency of renal clearance of pyrazinamide was demonstrated in steady-state serum concentration. The tissue/serum concentration ratio of pyrazinamide was highest in kidney and lowest in skeletal muscle among the tissues examined. The results suggested that a large fraction of pyrazinamide filtered by glomerulus and secreted by renal tubule was reabsorbed and this tubular reabsorption of pyrazinamide might be greatly influenced by urine flow.

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Floristic Characteristics of Vascular Plants in the Maryong-san(Mt. 406.7m) and Daeso-san(Mt. 286m) Area (마룡산(406.7m, 울진군)과 대소산(286m, 영덕군) 일원의 관속식물)

  • Kim, Young-Chul;Chae, Hyun-Hee;Park, You-Cheol;Lee, Seon-Mi;Nam, Gi-Heum
    • Korean Journal of Environment and Ecology
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    • v.35 no.5
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    • pp.438-479
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    • 2021
  • Basic information such as flora and their distribution are the key factors to consider for preserving plant diversity on a regional level. The number of plant species identified through a survey is closely related to the survey area and the number of habitats distributed within the survey area. In this study, we surveyed the flora of Mt. Maryong-san (PH) and Mt. Daeso-san (YH) located in Uljin-gun, Gyeongsangbuk-do, six and nine times, respectively. We planned to include a variety of habitats in the survey routes. As a result, we identified a total of 594 taxa composing of 112 families, 349 genera, 548 species, 10 subspecies, 34 varieties, and 2 formulas in the Mt. Maryong-san (PH) area and a total of 434 taxa composing of 89 families, 270 genera, 400 species, 9 subspecies, and 25 varieties in the Mt. Daeso-san (YH) area. Of the plants observed in the 21 habitats, the plants distributed in the transition zone around the valley and the dry grassland accounted for the highest proportion. The traditional graveyards located on the coast also served as the major habitat for the distribution of some plant species. In the two graveyards, 19 taxa of endemic plant species were surveyed. Moreover, the identified floristic target species included 1 taxon for grade V, 11 taxa for grade IV, and 24 taxa for grade III. A total of 77 taxa of naturalized plants were identified, and four of them were invasive alien plants as designated by the Ministry of Environment. The differences in the plants distributed in the area of Mt. Maryong-san (PH) and Mt. Daeso-san (YH) were mainly due to the difference in the size of each habitat distributed within the survey area. Moreover, it was judged that the entire vicinity of Mt. Daeso-san (YH) was not connected to the surrounding mountains and was an isolated area surrounded by farmland and residential areas.

Studies on the Fatty Acid Composition of Lipids from Some Seeds of the Cucurbitaceae Family (박과식물(科植物) 종자유(種子油)의 지방산(脂肪酸) 조성(組成))

  • Kim, Seong-Jin;Joh, Yong-Goe
    • Journal of the Korean Applied Science and Technology
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    • v.13 no.1
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    • pp.21-29
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    • 1996
  • Levels of total, neutral and polar lipids from the seeds of eight species of the Cucurbitaceae f Cucurbita moschata, Lufa cylindrica, Citrullus vulgari, Cucumis melo var. makuwa, Cucumis satvus, Lag leucantha. Trichosanthes kirilowii and Momordica charantia, were determinded, and their fatty compositions were also analyzed by gas-liquid chromatography. The results were summarized as foll. Lipid contents of the seeds range from 21.9 to 50.7%, which contained 98% up of neutral lipi the fatty acid compositon of ottal lipids from the seeds of Cucurbita moschata, Lufa cylindrica, Ci vulgari, Cucumis melo var. makuwa, Cucumis sativus and Lagenaria leucantha, linoleic acid is the mos dominant component(56.8${\sim}$84.0%) followed by oleic acid(5.7${\sim}$22.2%) and palmitic acid(6.1${\sim}$1) with a trace amount of ${\alpha}-linolenic$ acid(below 0.6%). On the contrary, the seed oils of Tricho kirilowii and Momordica charantia are characterized by presence of considerable amounts of con trienoic acid such as punicic acid($_{9c.11t.13c-}C_{18:3}$) and ${\alpha}-eleostearic$ acid($_{9c.11t.13c-}C_{18:3}$). For example total lipids of T. kirilowii seeds were mainly composed of linoleic acid(40.5%) and punicic acid(3) in the fatty acid composition, while those of M. charantia seeds predominantly comprised ${\alpha}-eleos$ acid as a main component(66.9%), accompanied by oleic acid(11.7%) and linoleic acid(10.4%). oil ${\beta}-eleostearic$ acid($_{9t.11t.13c-}C_{18:3}$) was checked as a trace. Fatty acid profiles of neutral lipids close resemblance to those of total lipids in all the seed oils, but are different from those of polar In particular, conjugate trienoic acids including punicic acid and ${\alpha}-eleostearic$ acid which are oc as the most abundant component in both neutral lipids of T. kirilowii and M. charantia seed oils, ar ent in a extremely small amount in both polar lipids. The fatty acid distribution in the polar lipid the samples except for T. kirilowii and M. charantia seed oils, showed a tendency of consid increased level of saturated fatty acids(25.0${\sim}$29.4%) compared with that in the neutral lipids(9.9%). The results obtained in this experiment suggest us that the seed oils of the Cucurbitaceae

Three-dimensional Model Generation for Active Shape Model Algorithm (능동모양모델 알고리듬을 위한 삼차원 모델생성 기법)

  • Lim, Seong-Jae;Jeong, Yong-Yeon;Ho, Yo-Sung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.43 no.6 s.312
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    • pp.28-35
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    • 2006
  • Statistical models of shape variability based on active shape models (ASMs) have been successfully utilized to perform segmentation and recognition tasks in two-dimensional (2D) images. Three-dimensional (3D) model-based approaches are more promising than 2D approaches since they can bring in more realistic shape constraints for recognizing and delineating the object boundary. For 3D model-based approaches, however, building the 3D shape model from a training set of segmented instances of an object is a major challenge and currently it remains an open problem in building the 3D shape model, one essential step is to generate a point distribution model (PDM). Corresponding landmarks must be selected in all1 training shapes for generating PDM, and manual determination of landmark correspondences is very time-consuming, tedious, and error-prone. In this paper, we propose a novel automatic method for generating 3D statistical shape models. Given a set of training 3D shapes, we generate a 3D model by 1) building the mean shape fro]n the distance transform of the training shapes, 2) utilizing a tetrahedron method for automatically selecting landmarks on the mean shape, and 3) subsequently propagating these landmarks to each training shape via a distance labeling method. In this paper, we investigate the accuracy and compactness of the 3D model for the human liver built from 50 segmented individual CT data sets. The proposed method is very general without such assumptions and can be applied to other data sets.

A Study on Relationships Between Environment, Organizational Structure, and Organizational Effectiveness of Public Health Centers in Korea (보건소의 환경, 조직구조와 조직유효성과의 관계)

  • Yun, Soon-Nyoung
    • Research in Community and Public Health Nursing
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    • v.6 no.1
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    • pp.5-33
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    • 1995
  • The objective of the study are two-fold: one is to explore the relationship between environment, organizational structure, and organizational effectiveness of public health centers in Korea, and the other is to examine the validity of contingency theory for improving the organizational structure of public health care agencies, with special emphasis on public health nursing administration. Accordingly, the conceptual model of the study consisted of three different concepts: environment, organizational structure, and organizational effectiveness, which were built up from the contingency theory. Data were collected during the period from 1st of May through 30th of June, 1990. From the total of 249 health centers in the country, one hundred and five centers were sampled non proportionally, according to the geopolitical distribution. Out of 105, 73 health centers responded to mailed questionnaire. The health centers were the unit of the study, and a various statistical analysis techniques were used: Reliability analysis(Cronbach's Alpha) for 4 measurement tools; Shapiro-Wilk statistic for normality test of measured scores of 6 variables: ANOVA, Pearson Correlaion analysis, regressional analysis, and canonical correlation analysis for the test of the relationships and differences between the variables. The results were. as follows : 1. No significant differences between forma lization, decision-making authority and environmental complexity were found(F=1.383, P=.24 ; F=.801, P=.37). 2. Negative relationships between formalization and decision-making authority for both urban and rural health centers were found(r=-.470, P=.002 ; r=-.348, P=.46). 3. No significant relationship between formalization and job satisfaction for both urban and rural health centers were found (r=-.242, P=.132, r=-.060, P=.739). 4. Significant positive relationship between decision - making authority and job satisfaction were found in urban health centers (r=.504, P=.0009), but no such relationship was observed in rural health centers. Regression coefficient between them was statistically significant($\beta=1.535$, P=.0002), and accuracy of regression line was accepted (W=.975, P= .420). 5. No significant relationships among formalization and family planning services, maternal health services, and tuberculosis control services for both urban and rural health centers were found. 6. Among decision-making authority and family planning services, maternal health services, and tuberculosis control services, significant positive relationship was found between de cision-making authority and family planning services(r=.286, P=.73). 7. A significant difference was found in maternal health services by the type of health centers (F=5.13, P=.026) but no difference was found in tuberculosis control services by the type of health centers, formalization, and decision-making authority. 8. A significant positive relationships were found between family planning services and maternal health services and tuberculosis control services, and between maternal health services and tuberculosis control services (r=-.499, P=.001 ; r=.457, P=.004 ; r=.495, P=.002) in case of urban health centers. In case of rural health centers, relationships between family planning services and tuberculosis control services, and between maternal health services and tuberculosis control services were statistically significant (r=.534, P=.002 ; r=.389, P=.027). No significant relationship was found between family planning and maternal health services. 9. A significant positive canonical correlation was found between the group of independent variables consisted of formalization and de cision-making authority and the group of dependent variables consisted of family planning services, maternal health services and tuberculosis control services(Rc=.455, P=.02). In case of urban health centers, no significant canonical correlation was found between them, but significant canoncial correlation was found in rural health centers(Rc=.578, P=.069), 10. Relationships between job satisfaction and health care productivity was not found significant. Through these results, the assumed relationship between environment and organizational structure was not supported in health centers. Therefore, the relationship between the organizational effectiveness and the congruence between environment and organizational structure that contingency theory proposes to exist was not able to be tested. However decision-making authority was found as an important variable of organizational structure affecting family planning services and job satisfaction in urban health centers. Thus it was suggested that decentralized decision making among health professionals would be a valuable strategy for improvement of organizational effectiveness in public health centers. It is also recommended that further studies to test contingency theory would use variability and uncertainty to define environment of public health centers instead of complexity.

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Radiation Absorbed Dose Calculation Using Planar Images after Ho-166-CHICO Therapy (Ho-166-CHICO 치료 후 평면 영상을 이용한 방사선 흡수선량의 계산)

  • 조철우;박찬희;원재환;왕희정;김영미;박경배;이병기
    • Progress in Medical Physics
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    • v.9 no.3
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    • pp.155-162
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    • 1998
  • Ho-l66 was produced by neutron reaction in a reactor at the Korea Atomic Energy Institute (Taejon, Korea). Ho-l66 emits a high energy beta particles with a maximum energy of 1.85 MeV and small proportion of gamma rays (80 keV). Therefore, the radiation absorbed dose estimation could be based on the in-vivo quantification of the activity in tumors from the gamma camera images. Approximately 1 mCi of Ho-l66 in solution was mixed into the flood phantom and planar scintigraphic images were acquired with and without patient interposed between the phantom and scintillation camera. Transmission factor over an area of interest was calculated from the ratio of counts in selected regions of the two images described above. A dual-head gamma camera(Multispect2, Siemens, Hoffman Estates, IL, USA) equipped with medium energy collimators was utilized for imaging(80 keV${\pm}$10%). Fifty-nine year old female patient with hepatoma was enrolled into the therapeutic protocol after the informed consent obtained. Thirty millicuries(110MBq) of Ho-166-CHICO was injected into the right hepatic arterial branch supplying hepatoma. When the injection was completed, anterior and posterior scintigraphic views of the chest and pelvic regions were obtained for 3 successive days. Regions of interest (ROIs) were drawn over the organs in both the anterior and posterior views. The activity in those ROIs was estimated from geometric mean, calibration factor and transmission factors. Absorbed dose was calculated using the Marinelli formula and Medical Internal Radiation Dose (MIRD) schema. Tumor dose of the patient treated with 1110 MBq(30 mCi) Ho-l66 was calculated to be 179.7 Gy. Dose distribution to normal liver, spleen, lung and bone was 9.1, 10.3, 3.9, 5.0 % of the tumor dose respectively. In conclusion, tumor dose and absorbed dose to surrounding structures were calculated by daily external imaging after the Ho-l66 therapy for hepatoma. In order to limit the thresholding dose to each surrounding organ, absorbed dose calculation provides useful information.

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Shallow subsurface structure of the Vulcano-Lipari volcanic complex, Italy, constrained by helicopter-borne aeromagnetic surveys (고해상도 항공자력탐사를 이용한 Italia Vulcano-Lipari 화산 복합체의 천부 지하 구조)

  • Okuma, Shigeo;Nakatsuka, Tadashi;Komazawa, Masao;Sugihara, Mitsuhiko;Nakano, Shun;Furukawa, Ryuta;Supper, Robert
    • Geophysics and Geophysical Exploration
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    • v.9 no.1
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    • pp.129-138
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    • 2006
  • Helicopter-borne aeromagnetic surveys at two different times separated by three years were conducted to better understand the shallow subsurface structure of the Vulcano and Lipari volcanic complex, Aeolian Islands, southern Italy, and also to monitor the volcanic activity of the area. As there was no meaningful difference between the two magnetic datasets to imply an apparent change of the volcanic activity, the datasets were merged to produce an aeromagnetic map with wider coverage than was given by a single dataset. Apparent magnetisation intensity mapping was applied to terrain-corrected magnetic anomalies, and showed local magnetisation highs in and around Fossa Cone, suggesting heterogeneity of the cone. Magnetic modelling was conducted for three of those magnetisation highs. Each model implied the presence of concealed volcanic products overlain by pyroclastic rocks from the Fossa crater. The model for the Fossa crater area suggests a buried trachytic lava flow on the southern edge of the present crater. The magnetic model at Forgia Vecchia suggests that phreatic cones can be interpreted as resulting from a concealed eruptive centre, with thick latitic lavas that fill up Fossa Caldera. However, the distribution of lavas seems to be limited to a smaller area than was expected from drilling results. This can be explained partly by alteration of the lavas by intense hydrothermal activity, as seen at geothermal areas close to Porto Levante. The magnetic model at the north-eastern Fossa Cone implies that thick lavas accumulated as another eruption centre in the early stage of the activity of Fossa. Recent geoelectric surveys showed high-resistivity zones in the areas of the last two magnetic models.

Diurnal and Seasonal Variations of the Radon Progeny Concentrations in the open Atmosphere and the Influence of Meteorological Parameters (대기중 라돈자핵종 농도의 일일 및 계절적 변화와 기상인자가 미치는 영향)

  • Lee, Dong-Myung;Kim, Chang-Kyu;Rho, Byung-Hwan;Lee, Seung-Chan;Kang, Hee-Dong
    • Journal of Radiation Protection and Research
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    • v.25 no.4
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    • pp.207-216
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    • 2000
  • Continuous measurements of radon progeny concentrations in the open atmosphere and measurements of meteorological parameters were performed in Tajeon, using a continuous gross alpha/beta aerosol monitor and a weather measuring equipment between July 1999 and July 2000. These data were analyzed for half-hourly, daily, and seasonal variations. The distribution of daily averaged equilibrium equivalent radon concentration$(EEC_{Rn})$ had an arithmetic mean value of $11.3{\pm}5.86Bqm^{-3}$ with the coefficient of variation of about 50% and the geometric mean was $10.3Bqm^{-3}$. The $EEC_{Rn}$ varies between 0.83 and $43.3Bqm^{-3}$, depending on time of day and weather conditions. Half-hourly averaged data indicated a diurnal pattern with the outdoor $EEC_{Rn}$ reaching a maximum at sunrise and a minimum at sunset. The pattern of the seasonal variation of the $EEC_{Rn}$ in Taejon had a tendency of minimum concentration occurring in the summer(July) and maximum concentration occurring in the late autumn(November). But the seasonal variation of the $EEC_{Rn}$ is expect to vary greatly from place to place. The outdoor $EEC_{Rn}$ was highly dependent on the local climate features. Particularly the $EEC_{Rn}$an rapidly drops less than $5Bqm^{-3}$ in case of blowing heavily higher than wind speed of $6msec^{-1}$, reversely the days with more than $30Bqm^{-3}$ were at a calm weather condition with the wind speed of lower than $1msec^{-1}$.

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