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Development of a Power-Free Cigarette Ashtray
No full text許多的研究中已調查出香煙燃燒的產物會對健康造成影響。過去的煙害防治上，主要是以預防抽煙、減少吸入及社會團體禁煙宣導為主，而技術導向的控制方式並不那麼受到關注。故此研究最終目的在發展或改善市面上現有的空氣清靜設備以去除旁流煙。
本研究利用旁流煙產生器，混合測試腔及採樣裝置構成系統去測得旁流煙的化學及物理特性。採樣裝置包括利用Q-TRAK偵測CO及CO2、利用PID偵測VOCs、使用濾紙收集微粒以求得質量濃度、並用type K的熱電偶測得香煙燃燒時的溫度。
實驗結果顯示氣流流量減少，無論是CO，CO2，VOCs，particle的排放因子和排放速率以及香煙燃燒時產生的溫度都會減少，而且香煙燃燒會較為完全。另外，煙灰缸材質的導熱係數對於氣膠及氣體的產生扮演著重要的角色，故設計擺放香煙的煙灰缸的凹槽是非常關鍵的。香煙燃燒速率會隨著煙灰缸凹槽接觸面的增加而減少，直到沒有足夠的熱量而熄滅。Numerous studies have been conducted to investigate the health effect. Historically, smoking-control efforts have focused on smoking prevention and cessation through individual and group counseling efforts. Compared to the policy-oriented control, the technology-oriented control measures do not receive as much attention as it deserves. Therefore, the ultimate goal of this work was to develop or improve the currently commercially air cleaners designed for removing sidestream cigarette smokes.
An experimental system, composed of a sidestream cigarette smoke generator, a mixing and test chamber, and a sampling train, was set up to investigate the chemical and physical characteristics of the sidestream cigarette smokes. Q-TRAK were used to monitor the concentrations of CO and CO2; PID was used to measure the concentration of VOCs. Filter samples were collected for estimating the mass concentration. We also measured the temperature of cigarette burning tip, by using a homemade thermocouple with type K.
The results showed that emission factors and emission rates of CO, CO2, aerosol mass concentration, VOCs, the surface temperature of the smoldering cone all decreased, and cigarettes would burn completely with decreasing passing air flow. The thermal conductivity of the ashtray played an important role in both aerosol and gas emission. The design of the trench holding the cigarette was particularly critical. The cigarette smoldering rate decreased with increasing contact area, until the combustion ceased due to not enough heat generation.目錄...............................................................1
表目錄.............................................................2
圖目錄.............................................................3
中文摘要...........................................................5
Abstract...........................................................6
一、 研究背景與目的...............................................7
二、 文獻探討.....................................................10
2-1煙害防治....................................................10
2-2旁流煙的危害................................................11
2-3燃燒特性....................................................12
2-4不同材質的導熱特性..........................................13
三、 研究方法.....................................................14
3-1 香煙燃燒速率之量測.........................................14
3-2 香菸燃燒產物之量測.........................................14
3-3 控制不同溼度的香煙對燃燒特性的影響.........................15
3-4 控制不同溫溼度的氣流對香煙燃燒速率的影響...................15
3-5 無煙煙灰缸的研發...........................................15
四、 結果與討論...................................................17
4-1 旁流煙的物化特性...........................................17
4-2 無動力無煙煙灰缸最佳化設計................................20
五、 結論........................................................27
參考文獻..........................................................29
表目錄
表一 污染物質量平衡................................................32
表二 自測熱傳導及工研院量測不同材質之比較..........................32
表三 煙灰缸四種不同體積(改變直徑及高度)............................33
表四 煙灰缸四種不同體積(改變直徑及高度)............................33
表五 出氣口數目多寡的燃燒速率與idling燃燒速率的比較...............34
表六 三種不同情況下，出氣孔大小的燃燒速率與自然情況燃燒速率的比較..34
表七 主動式不同氣流的燃燒速率與自然情況燃燒速率的比較..............3
Optimal stimulation during monitored thyroid surgery: EMG response characteristics in a porcine model
No full textObjectives: To compare electromyography (EMG) characteristics of the external branch of superior laryngeal nerve (EBSLN), recurrent laryngeal nerve (RLN), and vagus nerve (VN) evoked with different stimulation probes/dissectors during monitored thyroid surgery. Study Design: Experimental porcine model. Methods: In five piglets (10 EBSLNs/RLNs/VNs), laryngeal EMG was recorded by endotracheal tube surface electrodes with stimulation using five monopolar probes (group I), three bipolar probes (group II), and two stimulation dissectors (group III). The detectable EMG response (DER) was defined as > 100 μV and was obtained with these different probes/dissectors. Electromyography parameters, stimulus-response curve, and distance-sensitivity results were compared. Results: All stimulation probes/dissectors evoked typical EMG waveforms from the EBSLN/RLN/VN with 1 mA current. A stimulus-response curve with increasing EMG amplitude with increase in stimulating current was noted, with the maximum EMG elicited by group I/III probes/dissectors at < 1 mA and at a higher current for group II probes. All groups recorded lower evoked EMG amplitudes when the nerve was stimulated with overlying fascia or when probe/dissector to nerve distance was greater. The mean amplitude decreased by 11%/33%/13% in group I/II/III probes/dissectors when stimulating nerves covered by fascia versus nerves dissected free of overlying fascia. The rate of obtaining DER at 1- or 2-mm distance was significantly higher in group I than in group II/III probes/dissectors (P < 0.001). Latency did not change with any of the stimulation probes/dissectors or trials. Conclusion: Monopolar, bipolar probes, and newer stimulation dissectors all provided valid evoked VN/RLN/EBSLN waveforms. They have different functional sensitivity profiles and vary when stimulating with fascia and at a distance from the nerve. Selection of a stimulation probe/dissector for nerve monitoring can be based on the stimulation characteristics, the intended nerve monitoring application, and the surgeon's preference. Level of Evidence: N/A. Laryngoscope, 127:998–1005, 2017
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Evidence-based Analysis on The Clinical Impact of Intraoperative Neuromonitoring in Thyroid Surgery: State of the Art and Future Perspectives
No full textLaryngeal nerve injuries are one the most critical complications during thyroid and parathyroid surgery. Iatrogenic damages to the recurrent laryngeal nerve (RLN) are relevant in terms of clinical implications, economic costs, and for malpractice litigation. In order to minimize potential neural damages, a standardized surgical technique is mandatory. Intraoperatory neuromonitoring (IONM) of the RLN is an important adjunct to the traditional approach and is a reliable tool for neural mapping and in dissection and prognostication of postoperative neural function 4. Because of this, most of the iatrogenic damages are not related to direct transection, but they are visually undetectable. Notwithstanding the increasing use of IONM at this stage, there is still the need for prospective, randomized, well-powered, and well-designed trials in order to further validate (via evidence-based data) the role of IONM in thyroid surgery. The aim of this review is to provide a critical analysis of the scientific evidences on the clinical impact of IONM in thyroid surgery showing the unsolved problems and the future challenges
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