Flume tank and in situ trials for verification of static and dynamic methods for gear depth and underwater behavior of hairtail trolling lines

2018 ◽  
Vol 84 (6) ◽  
pp. 939-952
Author(s):  
Gebremeskel Eshetu Kebede ◽  
Chun Woo Lee ◽  
Subong Park ◽  
Mun Kwan Kim
Keyword(s):  
Dynamic Methods

Cost-effective air flow rate estimations using blowerdoor and wind speed measurements to assess building envelope thermal performances

2016 ◽  
Vol 40 (6) ◽  
pp. 504-529
Author(s):  
Simon Thébault ◽  
Jean-Robert Millet
Keyword(s):  
Wind Speed ◽  
Heat Loss ◽  
Cost Effective ◽  
Building Envelope ◽  
Loss Coefficient ◽  
Theory And Practice ◽  
Experimental Comparison ◽  
Tracer Gas ◽  
Dynamic Methods

Thermal performance discrepancies between theory and practice in buildings is a well known issue. Reducing this gap is crucial for enhancing energy efficient building construction and renovation. To measure the actual transmission heat loss coefficient of a building from in situ testing, an evaluation of time-varying infiltration losses needs to be quantified to improve the result’s precision, especially for short dynamic methods. This study first presents a theoretical analysis to explain why this evaluation is necessary and how to perform it using different technical approaches (simplified aeraulic models and tracer gas). An experimental comparison of four of these solutions on a small shed reveals that blowerdoor and wind speed measurements can be sufficient to evaluate infiltration losses with acceptable accuracy. Results of the identified transmission losses coefficient [Formula: see text] using the In Situ Assessment of Building EnvoLope pErformances (ISABELE) method shows how much the bias is reduced by including permeability specifications and local wind speed measurements. ISABELE is a measurement method of the overall transmission heat loss coefficient of a building.

Comparison of methods to quantify respirational carbon loss of coarse woody debris

2008 ◽  
Vol 38 (11) ◽  
pp. 2738-2745 ◽  
Author(s):  
Steffen Herrmann ◽  
Jürgen Bauhus
Keyword(s):  
Coarse Woody Debris ◽  
Measurement Method ◽  
Woody Debris ◽  
European Beech ◽  
Soda Lime ◽  
Carbon Loss ◽  
Dynamic Methods ◽  
Fagus Sylvatica L ◽  
Infrared Gas Analyser

Carbon (C) loss from coarse woody debris (CWD) may be important in forest ecosystem C budgets, yet there are no standard methods of quantifying it. Here we assessed respirational C loss of log segments of European beech ( Fagus sylvatica L.) and Norway spruce ( Picea abies (L.) Karst.), to compare the two main measurement approaches (the static and dynamic methods using soda lime and an infrared gas analyser, IRGA) with three different measurement options for CWD logs. These included (i) incubation of the whole log segment, (ii) the use of small in situ chambers on the curved log surface, and (iii) extracted wedges of wood. On average, significantly higher amounts of CO2 were measured with the IRGA (125%) compared with soda lime. In addition, the soda lime method requires careful calibration of incubation length and amounts of soda lime used. Regardless of the measurement method and tree species, substantially higher amounts of CO2 were measured for whole log segments than for the other two options. Measuring respiration with small in situ chambers on logs or extracted wedges might underestimate real CO2 flux by up to 74%. We therefore recommend measurement of CWD respiration using gas analysers for large log segments.

Rendez vous with Saturn's rings

1984 ◽  
Vol 75 ◽  
pp. 743-759 ◽  
Author(s):  
Kerry T. Nock
Keyword(s):  
Solar Energy ◽  
Electric Propulsion ◽  
Power Source ◽  
Propulsion System ◽  
Low Thrust ◽  
Ring Plane ◽  
The Earth ◽  
Total Impulse ◽  
Saturn's Rings

ABSTRACTA mission to rendezvous with the rings of Saturn is studied with regard to science rationale and instrumentation and engineering feasibility and design. Future detailedin situexploration of the rings of Saturn will require spacecraft systems with enormous propulsive capability. NASA is currently studying the critical technologies for just such a system, called Nuclear Electric Propulsion (NEP). Electric propulsion is the only technology which can effectively provide the required total impulse for this demanding mission. Furthermore, the power source must be nuclear because the solar energy reaching Saturn is only 1% of that at the Earth. An important aspect of this mission is the ability of the low thrust propulsion system to continuously boost the spacecraft above the ring plane as it spirals in toward Saturn, thus enabling scientific measurements of ring particles from only a few kilometers.

The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

1973 ◽  
Vol 31 ◽  
pp. 132-133 ◽  
Author(s):  
R. E. Herfert
Keyword(s):  
Surface Characterization ◽  
Analytical Techniques ◽  
X Ray Diffraction ◽  
Depth Of Penetration ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

Structural Studies on Mitotic Spindle Fibres

1978 ◽  
Vol 36 (3) ◽  
pp. 615-626
Author(s):  
J.R. Mcintosh
Keyword(s):  
Chemical Composition ◽  
Mitotic Spindle ◽  
Structural Studies ◽  
Mitotic Apparatus ◽  
Chemical Studies ◽  
Medical Interest ◽  
Spindle Fibres

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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