scholarly journals Installation of Test Setup and Measurement Procedures in Fir Wood Hydraulic Conductance Measurement

2021 ◽  
Vol 72 (2) ◽  
pp. 111-119
Author(s):  
Suheyla Esin Koksal ◽  
Gokhan Gunduz ◽  
Menderes Kalkat
Keyword(s):  
Pressure Difference ◽  
Wood Sample ◽  
Hydraulic Conductance ◽  
Conduction System ◽  
Seasonal Effects ◽  
Test Apparatus ◽  
Conductance Measurement ◽  
Test Setup ◽  
Time Period ◽  
Liquid Flows

For a hydraulic conductor, through which liquid flows, hydraulic conductance (K, ml·s-1·MPa-1) is defined as the ratio of pressure difference at the inlet and outlet to the fluid amount passing through the hydraulic conductor in a unit time period. This property is one of the key functions of the wood, and is obtained by the flow rate (F – Flow, ml·s-1) along the wood sample divided by the pressure difference driving the flow (DP, MPa). This study aimed to establish a test setup to determine the hydraulic conductance values of Uludağ Fir (Abies bornmulleriana Mattf.). A test setup was established to measure the amount of water that flows in samples and pressure difference in characterized capillary tubes. In addition, calibration of the test apparatus is explained in detail. Fir wood samples taken from Yedigoller, which is affiliated to Kale Operation Chieftainship and Bolu Forest Regional Directorate, of 4 mm in diameter and 3 cm in length were prepared and hydraulic conductance measurements were performed, and the results are presented in this article. The installed test setup was used to obtain the following information about trees: operation of the hydraulic conduction system, the amount of needed water, seasonal effects and stress-related changes.

A Method for Evaluating the Thermal Performance of Passenger Seats

2003 ◽  
Vol 217 (6) ◽  
pp. 449-459 ◽  
Author(s):  
E B Ratts ◽  
J W McElroy ◽  
W G Reed
Keyword(s):  
Thermal Performance ◽  
Thermal Energy ◽  
Water Source ◽  
Fixed Time ◽  
Test Method ◽  
Test Apparatus ◽  
Passenger Seat ◽  
Time Period ◽  
Seat Cushion ◽  
Heat And Moisture

In this paper, an experimental method to quantify the capability of an automotive seat to move heat and moisture away from the heat and water source is presented. To test the method, a test apparatus was constructed that generates heat and water vapour. The apparatus was placed on a seat cushion for a fixed time period. At the end of the period, heat and water transported were measured. These integrated values were used to quantify the seat's capability to move heat and moisture and ultimately to compare seats. By the impulse test method, the passenger seat had an effusivity of 94.7 W s1/2/m2 K. A non-ventilated seat transferred 5 W of thermal energy and an average of 0.36 g/min of water in 1800 s. A ventilated seat transferred 13.9 W of thermal energy and 0.70 g/min of water in 1800 s.

A Semi-Empirical Method for Estimating the Effective Leak and Vent Areas of an Airbag

1999 ◽  
Author(s):  
Aloysius U. Anagonye ◽  
J. T. Wang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Air Permeability ◽  
Empirical Method ◽  
Test Apparatus ◽  
Element Analysis ◽  
Test Setup ◽  
Surface Areas ◽  
Semi Empirical ◽  
Fabric Specimen

Abstract A semi-empirical method that utilizes tests from a small fabric specimen to quantify the effective leak and vent areas of an entire airbag is developed in this paper. The test setup and procedure used in the airbag material coupon tests are similar to the standard method used in determining air permeability of fabrics. A test apparatus for measuring the deflection of the fabric coupon was devised. Finite element analysis is used to compute the expanded vent and airbag surface areas of the coupon under various deformations. The leak and vent models were developed based on the results of a regression analysis. The effective vent area of a fabric coupon is a function of the ratio of the pressures across the fabric and the expanded vent area. Similarly, the effective leak area of a fabric coupon is a function of the ratio of the pressures across the fabric and the expanded surface area. The tested airbag materials were characterized with these models for use with finite element airbag models.

The Tempo and mode(S) of Prebiotic Evolution

1997 ◽  
Vol 161 ◽  
pp. 419-429 ◽  
Author(s):  
Antonio Lazcano
Keyword(s):  
Origin Of Life ◽  
Organic Compounds ◽  
Biological Evolution ◽  
Current Evidence ◽  
Early Diversification ◽  
Time Period ◽  
The Galaxy ◽  
History Of ◽  
Widespread Phenomenon ◽  
The Origin Of Life

AbstractDifferent current ideas on the origin of life are critically examined. Comparison of the now fashionable FeS/H2S pyrite-based autotrophic theory of the origin of life with the heterotrophic viewpoint suggest that the later is still the most fertile explanation for the emergence of life. However, the theory of chemical evolution and heterotrophic origins of life requires major updating, which should include the abandonment of the idea that the appearance of life was a slow process involving billions of years. Stability of organic compounds and the genetics of bacteria suggest that the origin and early diversification of life took place in a time period of the order of 10 million years. Current evidence suggest that the abiotic synthesis of organic compounds may be a widespread phenomenon in the Galaxy and may have a deterministic nature. However, the history of the biosphere does not exhibits any obvious trend towards greater complexity or «higher» forms of life. Therefore, the role of contingency in biological evolution should not be understimated in the discussions of the possibilities of life in the Universe.

Alteration of Mitochondria in Oxythiamine-Induced, Acute Thiamine Deficiency in the Mouse

1976 ◽  
Vol 34 ◽  
pp. 284-285
Author(s):  
Itaru Watanabe ◽  
Dante G. Scarpelli
Keyword(s):  
Electron Microscopy ◽  
Adult Male ◽  
Thiamine Deficiency ◽  
Light And Electron Microscopy ◽  
Fatty Change ◽  
Deficient Diet ◽  
Subcutaneous Injections ◽  
Swiss Mice ◽  
Time Period ◽  
Ad Libitum

Acute thiamine deficiency was produced in mice by the administration of oxythiamine, a thiamine analogue, superimposed upon a thiamine deficient diet. Adult male Swiss mice (30 gm. B.W.) were fed with a thiamine deficient diet ad libitumand were injected with oxythiamine (170 mg/Kg B.W.) subcutaneously on days 4 and 10. On day 11, severe lassitude and anorexia developed, followed by death within 48 hours. The animals treated daily with subcutaneous injections of thiamine (300 μg/Kg B.W.) from day 11 through 15 were kept alive. Similarly, feeding with a diet containing thiamine (600 μg/Kg B.W./day) from day 9 through 17 reversed the condition. During this time period, no fatal illness occurred in the controls which were pair-fed with a thiamine deficient diet.The oxythiamine-treated mice showed a significant enlargement of the liver, which weighed approximately 1.5 times as much as that of the pair-fed controls. By light and electron microscopy, the hepatocytes were markedly swollen due to severe fatty change and swelling of the mitochondria.

Is there a “universal” MAC equation?

1990 ◽  
Vol 48 (2) ◽  
pp. 228-229
Author(s):  
Robert E. Ogilvie
Keyword(s):  
Absorption Coefficient ◽  
Atomic Absorption ◽  
Atomic Number ◽  
X Ray ◽  
Time Period ◽  
Image Position

The search for an empirical absorption equation begins with the work of Siegbahn (1) in 1914. At that time Siegbahn showed that the value of (μ/ρ) for a given element could be expressed as a function of the wavelength (λ) of the x-ray photon by the following equationwhere C is a constant for a given material, which will have sudden jumps in value at critial absorption limits. Siegbahn found that n varied from 2.66 to 2.71 for various solids, and from 2.66 to 2.94 for various gases.Bragg and Pierce (2) , at this same time period, showed that their results on materials ranging from Al(13) to Au(79) could be represented by the followingwhere μa is the atomic absorption coefficient, Z the atomic number. Today equation (2) is known as the “Bragg-Pierce” Law. The exponent of 5/2(n) was questioned by many investigators, and that n should be closer to 3. The work of Wingardh (3) showed that the exponent of Z should be much lower, p = 2.95, however, this is much lower than that found by most investigators.

Clinical Update: Functional Capacity Evaluations—An Update

1999 ◽  
Vol 4 (5) ◽  
pp. 4-7 ◽  
Author(s):  
Laura Welch
Keyword(s):  
Job Performance ◽  
Functional Capacity ◽  
Injury Risk ◽  
Disability Evaluation ◽  
Time Period ◽  
Submaximal Effort ◽  
Lack Of Sleep ◽  
Overall Performance ◽  
Time Required ◽  
Specific Limitation

Abstract Functional capacity evaluations (FCEs) have become an important component of disability evaluation during the past 10 years to assess an individual's ability to perform the essential or specific functions of a job, both preplacement and during rehabilitation. Evaluating both job performance and physical ability is a complex assessment, and some practitioners are not yet certain that an FCE can achieve these goals. An FCE is useful only if it predicts job performance, and factors that should be assessed include overall performance; consistency of performance across similar areas of the FCE; consistency between observed behaviors during the FCE and limitations or abilities reported by the worker; objective changes (eg, blood pressure and pulse) that are appropriate relative to performance; external factors (illness, lack of sleep, or medication); and a coefficient of variation that can be measured and assessed. FCEs can identify specific movement patterns or weaknesses; measure improvement during rehabilitation; identify a specific limitation that is amenable to accommodation; and identify a worker who appears to be providing a submaximal effort. FCEs are less reliable at predicting injury risk; they cannot tell us much about endurance over a time period longer than the time required for the FCE; and the FCE may measure simple muscular functions when the job requires more complex ones.

Vitamin D Deficiency/Insufficiency and Challenges in Developing Global Vitamin D Fortification and Supplementation Policy in Adults

2012 ◽  
Vol 82 (4) ◽  
pp. 237-259 ◽  
Author(s):  
Moshe Ben-Shoshan
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Search Strategy ◽  
Epidemiologic Studies ◽  
Vitamin D Supplementation ◽  
Vitamin D Status ◽  
Societal Burden ◽  
Time Period ◽  
New Guidelines ◽  
In Cis

This review summarizes studies discussing vitamin D status in adults and reveals that vitamin D deficiency/insufficiency is highly prevalent in adults and that current fortification and supplementation policies are inadequate. Background and aims: Studies suggest a crucial role for adequate vitamin D status in various health conditions including bone metabolism, cancer, cardiovascular diseases, and allergies. However, relatively little is known about poor vitamin D status and unmet needs in adults. This report aims to highlight the contribution of epidemiologic studies (through the identification of health effects and societal burden) to the development of vitamin D fortification and supplementation policies and reveal unmet global challenges in adults. Methods: In order to assess worldwide vitamin D status in adults, the search strategy combined the medical literature database MEDLINE (using PubMed) for the time period between January 1, 1980 and February 28, 2011, using the key words “vitamin D” “deficiency” and “insufficiency”, and included articles in which access to full text was possible and in which healthy adults were assessed according to one of four commonly used vitamin D threshold classifications. Results: This report reveals that vitamin D deficiency occurs in 4.10 % [95 % CI (confidence interval), 3.93 %, 4.27 %] to 55.05 % (54.07 %, 56.03 %) of adults, while insufficiency occurs in 26.07 % (24.82 %, 27.33 %) to 78.50 % (77.85 %, 79.16 %), depending on the classification used. However, lack of overlap in CIs and high value of I2 statistics indicate considerable heterogeneity between studies. Further, certain populations (i. e. dark-skinned individuals, immigrants, and pregnant women) may be at higher risk for poor vitamin D status. Conclusion: Current policies for vitamin D supplementation and fortification are inadequate and new guidelines are required to improve vitamin D status in adults.

Negative Life Events Associated With Deliberate Self-Harm in an African Population in Uganda

Crisis ◽  
2005 ◽  
Vol 26 (1) ◽  
pp. 4-11 ◽  
Author(s):  
E. Kinyanda ◽  
H. Hjelmeland ◽  
S. Musisi
Keyword(s):  
Life Events ◽  
Negative Life Events ◽  
Life Time ◽  
Later Life ◽  
Dose Effect ◽  
Deliberate Self Harm ◽  
Time Period ◽  
Significant Difference ◽  
Self Harm ◽  
Suicide Interventions

Abstract. Negative life events associated with deliberate self-harm (DSH) were investigated in an African context in Uganda. Patients admitted at three general hospitals in Kampala, Uganda were interviewed using a Luganda version (predominant language in the study area) of the European Parasuicide Study Interview Schedule I. The results of the life events and histories module are reported in this paper. The categories of negative life events in childhood that were significantly associated with DSH included those related to parents, significant others, personal events, and the total negative life events load in childhood. For the later-life time period, the negative life events load in the partner category and the total negative life events in this time period were associated with DSH. In the last-year time period, the negative life events load related to personal events and the total number of negative life events in this time period were associated with DSH. A statistically significant difference between the cases and controls for the total number of negative life events reported over the entire lifetime of the respondents was also observed, which suggests a dose effect of negative life events on DSH. Gender differences were also observed among the cases. In conclusion, life events appear to be an important factor in DSH in this cultural environment. The implication of these results for treatment and the future development of suicide interventions in this country are discussed.

Stability and Change in Emotional Intelligence: Exploring the Transition to Young Adulthood

2005 ◽  
Vol 26 (2) ◽  
pp. 100-106 ◽  
Author(s):  
James D.A. Parker ◽  
Donald H. Saklofske ◽  
Laura M. Wood ◽  
Jennifer M. Eastabrook ◽  
Robyn N. Taylor
Keyword(s):  
High School ◽  
Emotional Intelligence ◽  
Postsecondary Education ◽  
Life Transition ◽  
Full Time ◽  
Major Life ◽  
Long Term Stability ◽  
Time Period ◽  
Transition From High School

Abstract. The concept of emotional intelligence (EI) has attracted growing interest from researchers working in various fields. The present study examined the long-term stability (32 months) of EI-related abilities over the course of a major life transition (the transition from high school to university). During the first week of full-time study, a large group of undergraduates completed the EQ-i:Short; 32 months later a random subset of these students (N = 238), who had started their postsecondary education within 24 months of graduating from high school, completed the measures for a second time. The study found EI scores to be relatively stable over the 32-month time period. EI scores were also found to be significantly higher at Time 2; the overall pattern of change in EI-levels was more than can be attributed to the increased age of the participants.

Sign in / Sign up

Export Citation Format

Share Document