35,430 research outputs found
Craspedochoeta hirsuticorpa Feng & Fan
No full texthirsuticorpa Feng & Fan in Feng et al., 1999: 321 (Craspedochoeta). Holotype male with labels: (1) printed with handwritten inscriptions on white label: “#375/ Kangding / 84.XII.4 ”; (2) handwritten on white label: “ 375 ♂ ”; (3) printed on red label: “ HOLOTYPE ”; (4) handwritten on white label: “ Craspedochoeta pilosa sp. nov ”. Preservation: pinned; genitalia dissected and mounted in a plastic tube. Additional notes: authors use the name “ hirsuticorpa ” when they published this species but not change the original label. Current name: Anthomyia hirsuticorpa (Feng & Fan, 1999).Published as part of ZHANG, XUFENG & ZHU, WEIBING, 2014, The types of Anthomyiidae (Diptera) in the Shanghai Entomological Museum, Chinese Academy of Science, China, pp. 1-67 in Zootaxa 3756 (1) on page 29, DOI: 10.11646/zootaxa.3756.1.1, http://zenodo.org/record/503313
The impact of organic matter enrichment on benthic chemical properties, microbial communities, and benthos in the estuary
No full text全世界水域環境污染的情況日益嚴重。以台灣為例，約有三分之二的河川呈現中度 (moderately) 或嚴重 (seriously) 污染，而北部最大河川淡水河由於承受大量生活污水的排放，使得像文蛤Meretrix lusoria這類生存在河口的生物受到嚴重影響。相對在沿岸環境的文蛤人工養殖區同樣也面臨到底質惡化，造成漁獲量降低，以及養殖池壽命縮短的問題。其實，不論河口污染或者是養殖池底泥的惡化，主要都是有機物質蓄積之後，所引發一連串底泥化學、微生物群聚，乃至於底棲動物的變動。
有機物質蓄積是底棲環境的關鍵性議題。水域中有機物質的堆積與否與流體運動及生物地球化學 (biogeochemistry) 代謝兩者息息相關。當流況減弱時，水中懸浮有機物質會沉澱積聚在底泥上，一般水中溶氧會與這些有機物質進行分解作用。當氧氣缺乏時，則以其它替代的化學物質，像是硝酸鹽 (nitrate)、硫酸鹽 (sulfate) 之類與有機物質進行厭氧性的降解 (anaerobic degradation)。這些好氧 (aerobic) 及厭氧代謝的結果都直接反映在底泥化學性質上。為了解有機物質蓄積下對底泥化學性質的影響，本論文測量淡水河河口至中游河段底泥中化學性質的縱向水平空間分布：於2001年採集下游與中游河段之底泥樣品進行硫化物質 (硫化氫, 酸可萃取硫 [acid-volatile sulfide; AVS]，黃鐵礦 [pyrite]) 含量及硫酸還原速率 (sulfate reduction rate; SRR) 的分析；於2002年採集近河口區、下游與中游河段之底泥樣品進行營養鹽含量 (硝酸鹽 [nitrate]、亞硝酸鹽 [nitrate]、磷酸鹽 [phosphate] 及矽酸鹽 [silicate]) 的分析。
綜合底泥化學性質的結果顯示，由間隙水中硝酸鹽、磷酸鹽與硫化氫特性的縱向空間組成分布，可將淡水河系底泥有機物降解的過程界定為三個類型：硝酸鹽富集型 (nitrate-abundance type) 出現在近河口區，間隙水硝酸鹽及磷酸鹽濃度分別為114.24及1.01To understand the integrated effects of organic matter loading on the benthic chemical properties, microbial communities, and benthos in an estuarine system, two field studies and a set of laboratory experiments were conducted. In the Tanshui River, the horizontal characteristics of the estuarine sediments were revealed in three spatial settings from the river mouth to a mid-reach section: a nitrate-abundance type, a phosphate-release type, and a sulfide-generation type; the vertical characteristics in four layers of Guandu sediment were also elucidated. With the exception of the mixed layer, a variety of metabolic processes by denitrifier strains occur in different vertical layers including nitrification-denitrification coupling processes in the nitrate-concentrated layer, denitrification or dissimilatory nitrate reduction to ammonium in the denitrifier-aggregation layer, and fermentation or spore formation in the ammonium-enriched layer. In addition, two laboratory experiments indicated that environmental condition gradually became worse, which leads to decreasing of dissolved oxygen, increasing of ammonium, nitrate and sulfide concentrate. However, high levels of treatment with the photosynthetic bacterium (PSB, Ectothiorhodospira sp.) decreased sulfide and nitrogenous nutrients in both aerated and hypoxic conditions, and then significantly improved the survival rate of the hard clam (Meretrix lusoria). In summary, the degree of organic matter degradation could be defined by the chemical properties in both the horizontal and vertical sediment profiles. A variety of metabolic processes by denitrifiers, which occur in the comparative sediment profile, indirectly correspond to these different stages. The use of the PSB, Ectothiorhodospira sp., actively removed some chemicals and mediated the sediment properties (from polluted to a transitory stage). Benthic hard clams can serve as a good indicator of the shift in benthic chemical processes toxic to the benthos, which are incapable of being detected by environmental measurements.Contents
Committee verified document (in Chinese) ………………………………….. i
Acknowledgment (in Chinese) ……………………………………………….. iii
Abstract in Chinese (中文摘要) ……………………………………………... v
Abstract in English …………………………………………………………… xi
Contents in English …………………………………………………………... xiii
Graph contents ……………………………………………………………….. xviii
Table contents ………………………………………………………………… xxii
Chapter 1. General introduction ……………………………………………… 1-1
Organic matter loading ………………………………………………….. 1-3
Adverse impacts of organic matter loading …………………………….. 1-4
Mitigating of organic matter loading …………………………………… 1-5
I. Chemical properties of sediments as organic matter is enriched ……... 1-6
II. Roles of microbes (denitrifier) with organic matter loading …………. 1-8
III. Mitigating the impact of organic matter loading using microbial (photosynthetic bacteria; PSB) addition ……………………………... 1-10
Questions to resolve …………………………………………………….. 1-13
Chapter 2. Compositions of nitrate, phosphate, and sulfide in interstitial water as indicators for defining the level of organic matter loading in the benthic environment ………………………………………... 2-1
Abstract …………………………………………………………………. 2-2
Introduction ……………………………………………………………... 2-4
Materials and methods ………………………………………………….. 2-9
Study site ……………………………………………………………… 2-9
Sample collection ……………………………………………………... 2-10
Analysis of chemical parameters in interstitial water ………………… 2-10
Sulfate reduction rate …………………………………………………. 2-11
PyritS and AVS ………………………………………………………... 2-11
Results …………………………………………………………………... 2-13
Distribution of sulfurous compounds …………………………………. 2-13
Distribution of various nutrients ……………………………………… 2-14
Discussion ………………………………………………………………. 2-15
References ………………………………………………………………. 2-21
Chapter 3. Distribution of nitrogenous nutrients and denitrifiers strains in estuarine sediment profiles of the Tanshui River, northern Taiwan . 3-1
Abstract …………………………………………………………………. 3-1
Introduction ……………………………………………………………... 3-1
Materials and methods ………………………………………………….. 3-2
Study site ……………………………………………………………… 3-2
Sample collection ……………………………………………………... 3-3
Analysis of environmental parameters ………………………………... 3-3
Determination of microbial communities …………………………….. 3-3
Isolate characterization ……………………………………………….. 3-4
DNA extraction and PCR amplification of 16S rDNA ……………….. 3-4
Sequence and phylogenic analysis of isolated strains ………………… 3-4
Results …………………………………………………………………... 3-4
Sediment profiles of environmental parameters ……………………… 3-4
Sediment profiles of viable bacteria …………………………………... 3-5
Sediment profiles of microbial strains ………………………………... 3-6
Discussion ………………………………………………………………. 3-7
Distributions of nitrogenous nutrients and denitrifier abundances …… 3-7
Properties of the denitrifying bacteria ………………………………… 3-9
References ………………………………………………………………. 3-10
Chapter 4. The use of photosynthetic bacterium (Ectothiorhodospira sp.) for mitigating the impact of organic matter loading in sediments on the hard clam (Meretrix lusoria) ………………………………….. 4-1
Abstract …………………………………………………………………. 4-2
Introduction ……………………………………………………………... 4-4
Materials and methods ………………………………………………….. 4-7
Experimental design …………………………………………………... 4-7
Sample collection ……………………………………………………... 4-9
Analysis of environmental parameters ……………………………….. 4-10
Data analysis ………………………………………………………….. 4-11
Results …………………………………………………………………... 4-13
Discussion ………………………………………………………………. 4-16
PSB’s effect under different oxic conditions …………………………. 4-17
PSB addition for the removal of sulfide ………………………............. 4-18
PSB addition for the removal of nitrogenous compounds ……………. 4-19
Hard clam as a bioindicator for environmental mitigation …................ 4-20
References ………………………………………………………............. 4-23
Chapter 5. Discussion ………………………………………………………... 5-1
Chemical Properties of Spatial Zonation in the Tanshui River …………. 5-1
Chemicals and Microbial Communities in Sediment Profile in the Estuary of Tanshui River ……………………………………………… 5-3
Microbes, Chemicals and Benthos Interaction in a Mesocosm System … 5-5
Determining the Extent of Organic Matter Loading of the Environment . 5-8
Mitigating the Adverse Effects of an Organic-Matter Accumulated Environment …………………………………………………………... 5-11
References ……………………………………………………………………. r-1
Appendage (in Chinese, 附錄) ………………………………………………. a-1
Publish records (發表記錄) …………………………………………….. a-1
Graph Contents
Chapter 1
Figure 1.1. Changes in fauna and sediment structure along a gradient of organic matter loading ……………………………………………………. 1-2
Figure 1.2. Effects of various hydraulic and biogeochemical characteristics on the fate of organic matter in estuarine environments ………………….. 1-3
Figure 1.3. Interactions of chemical properties in a sediment profile receiving organic matter input ………………………………………………………. 1-6
Figure 1.4. Physiological feasibilities of denitrifiers acclimating to the different chemical characteristics of a sediment profile accumulated with organic matter …………………………………………………………….. 1-8
Figure 1.5. Effects of the use of photosynthetic bacteria (PSB: Ectothiorhodospira sp.) to mitigate the adverse impacts of organic matter loading on the hard clam, Meretrix lusoria, as a monitoring indicator in the entire benthic system comprising sediment and water ……………...... 1-10
Figure 1.6. Impacts of organic matter loading on benthic properties, such as chemical properties, microbes, and the resident benthos, and the framework for the three questions addressed in this thesis ......................... 1-14
Chapter 2
Figure 2.1. Location of the Tanshui River in northern Taiwan .……………… 2-25
Figure 2.2. Vertical profiles of environmental factors, sulfide, sulfate, AVS, pyrite and sulfate reducing rate in the sediment of site T2 and T3 (from river mouth to upstream). Notice the scale change for the sulfate reducing rates ……………………………………………………………………….. 2-26
Figure 2.3. Vertical profiles of environmental factors, nitrate, nitrite, phosphate and silicate in the sediment of site T1, T2, and K1 in the Tanshui River system (from river mouth to the upstream) ……………….. 2-27
Figure 2.4. Summary of the spatial distribution of benthos compositions, the correspondent stages of benthic properties, the spatial distribution of chemical properties, nitrate, phosphate, and sulfide, in the Tanshui River, and the concordance of previous sediment profile summarized by author after 90o rotating ………………………………………………………….. 2-28
Chapter 3
Figure 3.1. Location of the Tanshui River Estuary in northern Taiwan ……… 3-2
Figure 3.2. Vertical profiles of environmental factors in the Guandu sediments …………………………………………………………………. 3-5
Figure. 3.3. Phylogenetic (left) and physiological (right) comparisons of denitrifier strains. Underlining indicates a denitrifier strain ……………… 3-7
Figure. 3.4. Summary of the concentrations of nitrate and ammonium, denitrifier abundance profiles, the vertical distribution of denitrifying isolated strains (one bold line for each strain), layer definitions, and corresponding metabolic strategies in the Tanshui River Estuarine sediments …………………………………………………………………. 3-8
Chapter 4
Figure 4.1. Dissolved oxygen, concentration of nitrate, sulfide and ammonium in water, sediment total organic carbon and total nitrogen, and the survival rate of clams with the addition of different levels of photosynthetic bacteria during the first experiment ……………………… 4-26
Figure 4.2. Dissolved oxygen, concentration of ammonium and sulfide in the water with the addition of different levels of photosynthetic, 0 or 0.5% total organic carbon of organic matter loading, and a porous/tight cap in the oxygen-depleting experiment ………………………………………… 4-27
Figure 4.3. A working model of Ectothiorhodospira sp. (PSB) removal of reduced compounds under an organic matter loading condition, through phototrophic sulfide oxidation and nitrogenous nutrient assimilation (ammonium and nitrate) ………………………………………………….. 4-28
Chapter 5
Figure 5.1. Summary of the spatial distribution of benthic compositions, the stages of benthic properties Pearson, the spatial distribution of chemical properties, such as nitrate, phosphate, and sulfide, in the Tanshui River, and the concordance of the previous sediment profile summarized by author after a 90o rotation ………………………………………………… 5-1
Figure 5.2. Summary of the concentrations of nitrate and ammonium, denitrifier abundance profiles, the vertical distribution of isolated denitrifying strains, layer definitions, and corresponding metabolic processes in the estuarine sediments of the Tanshui River ……………….. 5-5
Figure 5.3. A working model of Ectothiorhodospira sp. (PSB) removal of reduced compounds under an organic matter loading condition, through phototrophic sulfide oxidation and nitrogenous nutrient (ammonium and nitrate) assimilation, and which reflects on the survival of the hard clam, Meretrix lusoria …………………………………………………………... 5-7
Figure 5.4. Summary of the effects of fluctuations in benthic properties when undergoing organic matter loading on the chemical composition, the microbial (denitrifier) communities, the resident benthos, and the shift of benthic properties after microbial (photosynthetic bacteria; PSB) addition 5-8
Table Contents
Chapter 1
Chapter 2
Table 2.1. Summary of the of the hydraulic and sediment properties of the Tansui River at varying distanced from the river mouth …………………. 2-29
Table 2.2. Summary of the spatial distribution of maximum value of parameters in the sediment profile of the Tansui River at varying distanced from the river mouth …………………………………………… 2-30
Chapter 3
Table 3.1. Correlation analysis (Pearson correlation) of environmental parameters and microbial communities (viable bacteria) in sediments of the estuary of the Tanshui River at Guandu ………………………………. 3-5
Table 3.2. List of physiological tests and character groupings of 13 isolated strains ……………………………………………………………………... 3-6
Table 3.3. 16S rDNA similarity matrix of 13 isolated strains from the Tanshui Estuary and closely related bacteria from the NCBI database …………… 3-6
Chapter 4
Table 4.1. Summary of the two experimental designs ……………………….. 4-29
Table 4.2. Results of a general linear mode analysis of variance for environmental measurements and survival rate of hard clams with the addition of different levels of photosynthetic bacteria, different dates of sampling, and a blocking effect, in the first experiment ………………….. 4-30
Table 4.3. Comparison of regression coefficients of the best-fitting environment measurements to the survival rate of hard clams at each observation dates in different models of backward stepwise regression, including in condition of high and low photosynthetic bacteria, under loading with organic matter ………………………………………………. 4-31
Table 4.4a. Results of an analysis of variance for environmental measurements among the addition of different levels of photosynthetic bacteria, with/without OM loading, and a porously/tightly cap in a full-set design in the oxygen-depleting experiment ………………………………. 4-32
Table 4b. Results of a nonparametric analysis of variance (Kruskal-Wallis test) for environmental measurements among different levels of PSB addition and porous/tight cap in organic material-loading set in the oxygen-depleting experiment …………………………………………….. 4-32
Chapter
Crust-mantle interaction beneath the Luxi Block, eastern North China Craton: evidence from coexisting mantle- and crust-derived enclaves in a quartz monzonite pluton
No full textAbstract not availableTing-Guang Lan, Hong-Rui Fan, M. Santosh, Fang-Fang Hu, Kui-Feng Yang, Yue-Heng Yang, Yongsheng Li
Lan tai gui fan
No full textV.1. 難經經釋 : [二卷] / 扁鵲著 ; 徐大椿釋 -- v.2-3. 醫學源流論 : [二卷] / 徐靈胎著 -- v.4. 神農本草經百種錄 / 徐靈胎著 -- v.5. 醫貫砭 : [二卷] / 徐靈胎著 -- v.6. 傷寒論類方 / 徐大椿編輯 -- v.7-10. 蘭臺軌範 : 八卷 / 徐靈胎著.V.1. Nan jing jing shi : [er juan] / Bianque zhu ; Xu Dachun shi -- v.2-3. Yi xue yuan liu lun : [er juan] / Xu Lingtai zhu -- v.4. Shennong ben cao jing bai zhong lu / Xu Lingtai zhu -- v.5. Yi guan bian : [er juan] / Xu Lingtai zhu -- v.6. Shang han lun lei fang / Xu Dachun bian ji -- v.7-10. Lan tai gui fan : ba juan / Xu Lingtai zhu.[徐大椿].綫裝.框18x12公分, 9行25字, 小字雙行同. 白口, 左右雙邊, 單黑魚尾. 版心上鐫子目題, 中鐫卷次, 下鐫葉次.題名據叢書書名頁.書名頁印"徐氏醫書六種. 同治十二年夏湖北崇文書局重雕". 又有紅色戳記"漢口東壁垣選辦各直省宮書局並家藏一切善本書籍發兌"《中國叢書綜錄》(p.723)著錄.鈐"莊兆祥印", "莊兆祥".Xian zhuang.Kuang 18 x 12 gong fen, 9 hang 25 zi, xiao zi shuang hang tong. Bai kou, zuo you shuang bian, dan hei yu wei. Ban xin shang juan zi mu ti, zhong juan juan ci, xia juan ye ci.Ti ming ju cong shu shu ming ye.Detailed notes in vernacular field only.Detailed notes in vernacular field only.[Xu Dachun].Qian "Zhuang Zhaoxiang yin", "Zhuang Zhaoxiang"
Using performance assessment in secondary school mathematics: an empirical study in a Singapore classroom
No full textThis article reports an exploratory study on using performance assessment in mathematics instruction in a high-performing secondary school in Singapore. An intact mathematics class participated in the study, and received chapter-based performance tasks as intervention during regular mathematics lessons for about one and a half school years. The performance tasks used included authentic and/or open-ended tasks. The students’ academic achievements and attitudes in mathematics were compared with a comparison class that did not receive the intervention. Both quantitative and qualitative data were collected, mainly through questionnaire surveys, performance task tests, conventional school exams, and interviews with students and teachers. The results suggest that the students receiving the intervention performed significantly better than their counterparts in solving conventional exam problems, and in general they also showed more positive changes in attitudes towards mathematics and mathematics learning. The students from the experimental class also expressed positive views about the benefits of using performance tasks in promoting their ability in higher order thinking, though no statistically significant difference was detected between the two classes of students in solving unconventional tasks before and after intervention. Overall, the results appear to support teachers’ using contextualised problems in real life situations and open-ended investigations in students’ learning of mathematic
Evolution of the lithospheric mantle beneath the southeastern North China Craton: constraints from mafic dikes in the Jiaobei terrain
No full textAbstract not availableYa-Chun Cai, Hong-Rui Fan, M. Santosh, Xuan Liu, Fang-Fang Hu, Kui-Feng Yang, Ting-Guang Lan, Yue-Heng Yang, Yongsheng Li
Use of fan rig data for the understanding and prediction of fan broadband noise and noise changes due to a variable area nozzle
No full textThis thesis presents the results of the research component of this EngD, entitledUse of fan rig data for the understanding and prediction of fan broadband noise and noisechanges due to a variable area nozzleAs suggested by the title, fan rig noise measurements form an integral part of this thesis. Theanalysis of a database of rig noise measurements forms the first section of this thesis, in twoparts. The first part describes the analysis of a set of fan rig noise measurements, including thevariation of fan broadband and tone noise in forward and rearward arcs. The second partexamines a large database of fan rig noise measurements, and attempts to derive correlationsof fan broadband noise and fan performance parameters. Cluster Analysis, PrincipleComponent Analysis, and Regression Analysis are used to understand and describe theunderlying physics of broadband noise generation and the relationships between thesepredictors.The second section of this thesis uses a cascade broadband noise model to investigate rotorstatorbroadband noise. Predictions of the broadband noise from this noise model arecompared to rig measurements, showing good accuracy. The underlying physics of rotorstatorbroadband noise generation is investigated by performing two parametric studies usingthe broadband noise model. The first parametric study investigates the effect on broadbandnoise of simple flow and geometric parameters, namely number of vanes, vane chord, vanestagger angle, and rotor wake turbulence intensity, turbulent length scale, and flow Machnumber onto the cascade. These results are used to derive scaling power laws for theprediction of changes in broadband noise due to changes in these parameters. The secondparametric study expands upon this by investigating the effect on broadband noise of the fandesign parameters shaft speed, pressure ratio, and efficiency, at approach, cutback and cruiseconditions. The variation in broadband noise due to these design parameters is explained byconsidering the underlying flow and geometric parameters such as number of vanes and Machnumber, and the scaling power laws based on these simple parameters are used to predict thechange in broadband noise between different performance points.The final section of this thesis investigates the effect of varying exhaust nozzle area on totalengine noise. A new method is presented that allows the transfer of changes in fan rig noise toEugene P. Deane EngD Thesis September 2009 2engine noise predictions, to estimate the change in fan noise due to the pressure ratio changesbrought about by a variable area nozzle. Changes in engine noise are investigated forapproach, cutback, and sideline conditions, and the application of the new method assessed.As the research displayed in this thesis is closely linked to industry, the foundation of workpresented in several chapters is dependent on data or figures that are commercially sensitive.It has therefore been necessary to create a confidential appendix (Appendix X) to includethese commercially sensitive items. These additional results and figures in Appendix X aresupplementary in nature, and sufficient results are presented in the public thesis to illustratethe results of the various chapters. Where supplementary information and results are available,this is clearly indicated at the pertinent point in the published thesis, along with the section ofAppendix X where the information can be found
Lao ge ming yu dao xin wen ti!
No full text东风造反队.文字: 老革命遇到新问题! ;下款: 东风造反队 批刘先锋画展 一九六七.十二.三.裝裱後高寬: 115 x 49 cm.Dong feng zao fan dui.Wen zi : Lao ge ming yu dao xin wen ti! ; Xia kuan : Dong feng zao fan dui pi Liu xian feng hua zhan 1967. 12. 3.Zhuang biao hou gao kuan : 115 x 49 cm
Richardson, Barbauld, and the construction of an early modern fan club
No full textMPhilMuch has been written about the life and long works of the eighteenth century epistolary novelist, Samuel Richardson, but the prospect of his position as the first celebrity novelist – responsible for courting his own fame as well as initiating his own fan club – has largely been ignored. The body of manuscripts housed at the National Art Library in the Victoria and Albert Museum in London provides the modern scholar with evidence of the skeletal beginnings of an early fan club. This thesis aims to show how these manuscripts were turned into a saleable commodity by the publisher and entrepreneur Richard Phillips, while under the guiding hand of another, slightly later, literary celebrity, Anna Laetitia Barbauld. In order to restore Richardson’s reputation amongst a new nineteenth century audience, Barbauld was required to construct her own idea of him as an eighteenth century celebrity author, and in doing so the insecurities of a self-professed, apparently diffident man, are revealed. Barbauld’s capacious, but heavily edited selection of letters is analyzed in this thesis, providing ample evidence that Richardson’s correspondents were more than just eager letter writers. By using Barbauld’s biography of Richardson this thesis aims to show how she manipulates the genre of life writing in her construction of him.
This thesis offers an alternative reading of how the Richardson manuscripts are viewed, redefining them as not simply a collection of letters, but as a collective entity, deliberately selected and archived as evidence of an early modern fan club, and its celebrity managing director
Uncertainty Analysis for In-situ Fan Curve Calibration in Variable Air Volume Systems
Get PDFIn order to obtain in-situ fan performance curves for variable air volume (VAV) air handling units (AHUs) with predicted uncertainties, airflow measurements for an extended time and a tailored calibration procedure were proposed and validated in this work.
To obtain airflow measurement for an extended time, traverse measurements through the Equal-Area method were first conducted to select 3 sampling points (3-P) that represented the average velocity at a measurement plane. Next, through statistical analysis, additional uncertainty generated when reducing the number of sampling points was accounted for in terms of sampling time, reduced number of sampling points, measurement location, and comparison to common airflow measurement stations (AFMS). As a result of these analyses, it was found that for sampling times of 60 seconds, uncertainties below 5% can be expected from 3-P measurements when airflow velocity is above 800 fpm. Analysis showed that for return air (RA) measurements where velocities below 800 fpm are common, more than 3-P would be necessary to comply with 5% accuracy per ASHRAE Standard 111 [2008] requirements.
Next, it was demonstrated through comparison of measurement conditions and uncertainties for supply air (SA) that a relationship between measurement location and uncertainty of the 3-P measurement exists. Finally, the results showed that AFMS utilized more sampling points than necessary to achieve 5% accuracy in every test case. Performing airflow measurements with a tailored selection of sampling points was more effective than following cross-sectional area-based industry guidelines.
Upon the completion of the airflow uncertainty analyses, a calibration procedure for VAV AHUs was also produced and tested to obtain in-situ fan performance curves. In addition, based on the ANSI/ASHRAE Standard 51 [1999], an uncertainty analysis was performed on adjusted measurements by fan laws to build in-situ fan performance curves. Uncertainty bands at 95% confidence showed that previously defined airflow measurement uncertainty is the most sensible variable. Results showed that while application of fan laws can be applicable to return fans (RFs), higher uncertainties can be expected as airflow velocities below 800 fpm are common. Nevertheless, since SA average velocities were generally above 800 fpm, narrow uncertainty intervals were observed.
In conclusion, a practical and reliable approach for in-situ fan performance curves calibration was explored using statistical analysis and uncertainty propagation of airflow, fan head, and fan power uncertainties. Airflow measurements for extended sampling times were successfully achieved after developing a prototype holding bracket design for reducing field technician dependency. Finally, a VAV AHU calibration procedure for obtaining in-situ fan performance curves with actual range and visible system effect impacts was successfully applied and validated through this thesis work
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