Evaluation of relative density, diameter growth, and stem form in a red spruce (Picearubens) stand 15 years after precommercial thinning

1992 ◽  
Vol 22 (2) ◽  
pp. 229-238 ◽  
Author(s):  
R. James Barbour ◽  
R.E. Bailey ◽  
Jean A. Cook
Keyword(s):  
Relative Density ◽  
Red Spruce ◽  
Stem Form ◽  
Eastern Canada ◽  
Precommercial Thinning ◽  
X Ray ◽  
Total Height ◽  
The Difference ◽  
And Control ◽  
Average Relative Density

Thirty red spruce (Picearubens Sarg.) trees were harvested from a precommercial thinning trial near St. Margaret's Bay, Nova Scotia. Total height was measured, and samples were removed from the following five stem heights: stump height, breast height, 25, 50, and 75% of total height. Relative density and growth rate were measured using X-ray densitometry, and taper was calculated for log and tree lengths. Growth rates were significantly greater on the treatment plot than on the control plot. No significant differences in relative density were found between trees from the treatment plot (2.4 × 2.4 m spacing) and trees from the unthinned control. The relative density of the treatment and control trees was also compared with the species average relative density for red spruce. No significant differences were found, except for the relative density at stump height in the after-treatment portion of the trees from the thinned plot. The difference was not considered great enough to cause a deterioration of the mechanical properties of lumber or the yield of pulp produced from this material. The taper factor was significantly different between the treatment and control plots, but the taper factor for the treatment trees was similar to that for the spruce resource currently being processed in eastern Canada.

Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane

1982 ◽  
Vol 40 ◽  
pp. 74-75
Author(s):  
Jules S. Jaffe ◽  
Robert M. Glaeser
Keyword(s):  
Purple Membrane ◽  
Data Set ◽  
High Resolution Data ◽  
X Ray ◽  
X Ray Crystallography ◽  
Fourier Techniques ◽  
Versus Protein ◽  
The Difference ◽  
Difference Fourier ◽  
Ideal Method

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.

X-Ray Replication of Submicrometer Linewidth Patterns

1977 ◽  
Vol 35 ◽  
pp. 136-137
Author(s):  
Henry I. Smith ◽  
D.C. Flanders
Keyword(s):  
Electron Beam Lithography ◽  
Cross Sectional ◽  
X Ray ◽  
Electron Backscattering ◽  
Spatial Frequencies ◽  
Cross Sectional Profile ◽  
Carbon Foils ◽  
Sectional Profile ◽  
And Control ◽  
Soft Radiation

Scanning electron beam lithography has been used for a number of years to write submicrometer linewidth patterns in radiation sensitive films (resist films) on substrates. On semi-infinite substrates, electron backscattering severely limits the exposure latitude and control of cross-sectional profile for patterns having fundamental spatial frequencies below about 4000 Å(l),Recently, STEM'S have been used to write patterns with linewidths below 100 Å. To avoid the detrimental effects of electron backscattering however, the substrates had to be carbon foils about 100 Å thick (2,3). X-ray lithography using the very soft radiation in the range 10 - 50 Å avoids the problem of backscattering and thus permits one to replicate on semi-infinite substrates patterns with linewidths of the order of 1000 Å and less, and in addition provides means for controlling cross-sectional profiles. X-radiation in the range 4-10 Å on the other hand is appropriate for replicating patterns in the linewidth range above about 3000 Å, and thus is most appropriate for microelectronic applications (4 - 6).

Antiphase Boundaries in Ordered Ni3FE Crystals

1969 ◽  
Vol 27 ◽  
pp. 62-63
Author(s):  
Y. H. Liu
Keyword(s):  
Domain Size ◽  
Antiphase Domain ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hardening Mechanism ◽  
Superlattice Structure ◽  
Disordered Phase ◽  
Domain Boundaries ◽  
Atomic Scattering ◽  
The Difference

Ordered Ni3Fe crystals possess a LI2 type superlattice similar to the Cu3Au structure. The difference in slip behavior of the superlattice as compared with that of a disordered phase has been well established. Cottrell first postulated that the increase in resistance for slip in the superlattice structure is attributed to the presence of antiphase domain boundaries. Following Cottrell's domain hardening mechanism, numerous workers have proposed other refined models also involving the presence of domain boundaries. Using the anomalous X-ray diffraction technique, Davies and Stoloff have shown that the hardness of the Ni3Fe superlattice varies with the domain size. So far, no direct observation of antiphase domain boundaries in Ni3Fe has been reported. Because the atomic scattering factors of the elements in NijFe are so close, the superlattice reflections are not easily detected. Furthermore, the domain configurations in NioFe are thought to be independent of the crystallographic orientations.

Analysis of the horizontal structure of a measurement and control geodetic network based on entropy

2013 ◽  
Vol 62 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Maria Mrówczyńska
Keyword(s):  
Geodetic Network ◽  
The State ◽  
Observation System ◽  
Optimum Number ◽  
Optimum Structure ◽  
Horizontal Structure ◽  
The Difference ◽  
And Control ◽  
Measurement And Control ◽  
Horizontal Displacements

Abstract The paper attempts to determine an optimum structure of a directional measurement and control network intended for investigating horizontal displacements. For this purpose it uses the notion of entropy as a logarithmical measure of probability of the state of a particular observation system. An optimum number of observations results from the difference of the entropy of the vector of parameters ΔHX̂ (x)corresponding to one extra observation. An increment of entropy interpreted as an increment of the amount of information about the state of the system determines the adoption or rejection of another extra observation to be carried out.

PENINGKATAN KEMANDIRIAN BELAJAR SISWA SMP MELALUI PEMBELAJARAN BERBASIS MASALAH

2019 ◽  
Vol 8 (2) ◽  
Author(s):  
Tanti Jumaisyaroh Siregar
Keyword(s):  
Problem Based Learning ◽  
Mathematic Teacher ◽  
Self Regulated Learning ◽  
Regulated Learning ◽  
Quasi Experimental ◽  
Independent Variable ◽  
Direct Learning ◽  
The Difference ◽  
And Control ◽  
Learning Data

The purposes of this research were to know: the difference of improvement in self-regulated learning of students that given problem-based learning with students that given  direct learning. The type of this research is a quasi-experimental research by taking samples from the existing population. The variable of this research consist of independent variable that is problem based learning model while the dependent variable isself regulated learning of student.The population of this research is all students of SMP Swasta Ar-rahman Percut and the sample of this research is grade eight with taken sample two classes (experiment and control)  with total 60 students. The instrument of this research were: scale of self-regulated learning. Data that have been collected then analyzed and performed hypothesis testing by using T-test. Based of the results analysis, it showed that: improvment  of the students’ self-regulated learning that given problem-based learning was higher than the students’ ability that given direct learning His then, suggested that problem-based learning be used as an alternative for mathematic teacher to improved students’ ability in mathematical critical thinking and self-regulated learning.

FINANCIAL CONTROLLING IN THE SYSTEM OF FINANCIAL MANAGEMENT

2018 ◽  
Vol 28 (1) ◽  
pp. 137-141
Author(s):  
Petya Yordanova – Dinova
Keyword(s):  
Comparative Analysis ◽  
Financial Management ◽  
Financial Stability ◽  
Business Environment ◽  
Innovative Approach ◽  
Financial Sustainability ◽  
The Common ◽  
The Difference ◽  
Effective Use ◽  
And Control

This paper explores the comparative analysis of the financial controlling, who is a result from the common controlling concept and the financial management. In the specialized literature, financial controlling is seen as an innovative approach to financial management. It is often presented as the most promising instrument of financial diagnostics. Generally speaking, financial controlling is seen as a process of managing the company`s assets which are valued in monetary measures. The difference between the financial management and the financial controlling is that the second covers all functions of management, analysis and control of finances, aiming at maximizing their effective use and increasing the value of the enterprise. Financial controlling is often seen as a function of the common practice of financial management. Its objective is to preserve the financial stability and financial sustainability of enterprises operating in a highly aggressive business environment.

scholarly journals Effects of Clonostachys rosea f. catenula Inoculum on the Composting of Cabbage Wastes and the Endophytic Activities of the Composted Material on Tomatoes and Red Spider Mite Infestation

2021 ◽  
Vol 9 (6) ◽  
pp. 1184
Author(s):  
Nomfusi Ntsobi ◽  
Morris Fanadzo ◽  
Marilize Le Roes-Hill ◽  
Felix Nchu
Keyword(s):  
Seed Germination ◽  
Spider Mite ◽  
Fungal Treatment ◽  
Tomato Seed ◽  
Clonostachys Rosea ◽  
Tomato Plants ◽  
Red Spider Mite ◽  
Phytotoxicity Test ◽  
The Difference ◽  
And Control

Globally, fungal inocula are being explored as agents for the optimization of composting processes. This research primarily evaluates the effects of inoculating organic vegetable heaps with the entomopathogenic fungus Clonostachys rosea f. catenula (Hypocreales) on the biophysicochemical properties of the end-product of composting. Six heaps of fresh cabbage (Brassica oleracea var. capitata) waste were inoculated with C. rosea f. catenula conidia and another six were not exposed to the fungus. The composted materials from the fungus- and control-treated heaps were subsequently used as a medium to cultivate tomatoes (Solanum lycopersicum). The biophysicochemical characteristics of the composted materials were also assessed after composting. In addition, the protective effect of the fungal inoculum against red spider mite (Tetranychus urticae) infestations in the tomatoes was evaluated through the determination of conidial colonization of the plant tissue and the number of plants infested by the insect. Furthermore, phytotoxicity tests were carried out post experiment. There were few significant variations (p < 0.05) in heap temperature or moisture level between treatments based on the weekly data. We found no significant differences in the levels of compost macronutrient and micronutrient constituents. Remarkably, the composted materials, when incorporated into a growth medium from fungus-treated heaps, induced a 100% endophytic tissue colonization in cultivated tomato plants. While fewer red spider mite infestations were observed in tomato plants grown in composted materials from fungus-treated heaps, the difference was not significant (χ2 = 0.96 and p = 0.32). The fungal treatment yielded composted materials that significantly (p < 0.05) enhanced tomato seed germination, and based on the phytotoxicity test, the composted samples from the heaps exposed to the C. rosea f. catenula inoculum were not toxic to tomato seeds and seedlings. In conclusion, this study showed that C. rosea f. catenula improved the quality of composted materials in terms of fungal endophytism and seed germination.

scholarly journals Evaluating the Impact of Floods on Housing Price Using a Spatial Matching Difference-In-Differences (SM-DID) Approach

2021 ◽  
Vol 13 (2) ◽  
pp. 804
Author(s):  
Jean Dubé ◽  
Maha AbdelHalim ◽  
Nicolas Devaux
Keyword(s):  
Housing Price ◽  
Hedonic Pricing ◽  
Environmental Amenities ◽  
Sale Price ◽  
Difference In Differences ◽  
Hedonic Pricing Model ◽  
The Difference ◽  
And Control ◽  
The Impact ◽  
The City

Many applications have relied on the hedonic pricing model (HPM) to measure the willingness-to-pay (WTP) for urban externalities and natural disasters. The classic HPM regresses housing price on a complete list of attributes/characteristics that include spatial or environmental amenities (or disamenities), such as floods, to retrieve the gradients of the market (marginal) WTP for such externalities. The aim of this paper is to propose an innovative methodological framework that extends the causal relations based on a spatial matching difference-in-differences (SM-DID) estimator, and which attempts to calculate the difference between sale price for similar goods within “treated” and “control” groups. To demonstrate the potential of the proposed spatial matching method, the researchers present an empirical investigation based on the case of a flood event recorded in the city of Laval (Québec, Canada) in 1998, using information on transactions occurring between 1995 and 2001. The research results show that the impact of flooding brings a negative premium on the housing price of about 20,000$ Canadian (CAN).

scholarly journals Microstructure evolution of TC4 powder by spark plasma sintering after hot deformation

2020 ◽  
Vol 39 (1) ◽  
pp. 457-465
Author(s):  
Jiangpeng Yan ◽  
Zhimin Zhang ◽  
Jian Xu ◽  
Yaojin Wu ◽  
Xi Zhao ◽  
...  
Keyword(s):  
Strain Rate ◽  
Relative Density ◽  
Spark Plasma Sintering ◽  
Hot Deformation ◽  
Tc4 Titanium Alloy ◽  
Weave Structure ◽  
Plasma Sintering ◽  
Spark Plasma ◽  
Average Relative Density ◽  
Low Strain Rate

AbstractThe cylindrical samples of TC4 titanium alloy prepared by spark plasma sintering (SPS) were compressed with hot deformation of 70% on the thermosimulation machine of Gleeble-1500. The temperature of the processes ranged from 850°C to 1,050°C, and the strain rates varied between 0.001 and 5 s−1. The relative density of the sintered and compressed samples was measured by the Archimedes principle. During hot deformation, the microstructure of the sample was observed. The results show that the average relative density of the samples was 90.2% after SPS. And the relative density was about 98% after the hot deformation of 70%. Under high temperature (>950°C), the sensitivity of flow stress to temperature was reduced. At low strain rate (0.001 s−1), the increase in the deformation temperature promoted the growth of dynamic recrystallization (DRX). At the same temperature, the increase in strain rate slowed down the growth of DRX grains. And the variation tendency was shown from the basket-weave structure to the Widmanstätten structure at a low strain rate (<0.1 s−1), with increase in the strain rate.

scholarly journals Ability of radiofrequency echographic multispectrometry to identify osteoporosis status in elderly women with type 2 diabetes

2021 ◽  
Author(s):  
Carla Caffarelli ◽  
Maria Dea Tomai Pitinca ◽  
Antonella Al Refaie ◽  
Elena Ceccarelli ◽  
Stefano Gonnelli
Keyword(s):  
Type 2 Diabetes ◽  
Lumbar Spine ◽  
Elderly Women ◽  
Fragility Fractures ◽  
Dual Energy ◽  
Healthy Controls ◽  
Diagnosis Of Osteoporosis ◽  
X Ray ◽  
The Difference

Abstract Background Patients with type 2 diabetes (T2DM) have an increased or normal BMD; however fragility fractures represent one of the most important complications of T2DM. Aims This study aimed to evaluate whether the use of the Radiofrequency Echographic multi spectrometry (REMS) technique may improve the identification of osteoporosis in T2DM patients. Methods In a cohort of 90 consecutive postmenopausal elderly (70.5 ± 7.6 years) women with T2DM and in 90 healthy controls we measured BMD at the lumbar spine (LS-BMD), at femoral neck (FN-BMD) and total hip (TH-BMD) using a dual-energy X-ray absorptiometry device; moreover, REMS scans were also carried out at the same axial sites. Results DXA measurements were all higher in T2DM than in non-T2DM women; instead, all REMS measurements were lower in T2DM than in non T2DM women. Moreover, the percentage of T2DM women classified as “osteoporotic”, on the basis of BMD by REMS was markedly higher with respect to those classified by DXA (47.0% vs 28.0%, respectively). On the contrary, the percentage of T2DM women classified as osteopenic or normal by DXA was higher with respect to that by REMS (48.8% and 23.2% vs 38.6% and 14.5%, respectively). T2DM women with fragility fractures presented lower values of both BMD-LS by DXA and BMD-LS by REMS with respect to those without fractures; however, the difference was significant only for BMD-LS by REMS (p < 0.05). Conclusions Our data suggest that REMS technology may represent a useful approach to enhance the diagnosis of osteoporosis in patients with T2DM.

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