logarithmic relationship
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2022 ◽  
Vol 12 (2) ◽  
pp. 686
Author(s):  
Ziwen Huo ◽  
Xingdong Deng ◽  
Xuepeng Zhang ◽  
Wei Chen

Land use/land cover (LULC) has an important impact on the ecological environment and is crucial for calculating ecosystem service values (ESVs). However, whether and to what extent the ESVs vary when calculated by LULC product data at different spatial scales remain unclear. Data from two LULC products were used in this study, and two datasets with different spatial scales were obtained by resampling. Then, the ESVs were calculated by the equivalent factor method. Finally, the impacts of LULC on ESVs at different scales were studied, revealing the following: (1) The ESVs calculated by LULC products and by the same products at different scales are different. (2) The difference in the ESVs calculated by the two LULC datasets is approximately 28%, and the difference tends to decrease with increasing scale. (3) With an increase in the LULC scale, the overall change trend of ESVs also increases, and the increasing trend gradually moderates. In addition, the ESVs and LULC scale conform to a logarithmic relationship, and the coefficient of determination (R2) is greater than 0.7. These results have important reference value for obtaining reliable ESVs.


2021 ◽  
Vol 9 ◽  
Author(s):  
Liang Chen ◽  
Hancheng Ji ◽  
Nansheng Qiu ◽  
Liang Zhang

The grain sizes of clastic rock sediments serve as important depositional indicators that are significant in sedimentology and petroleum geology studies. Generally, gamma ray, spontaneous-potential and resistivity well logs are utilized to qualitatively characterize variations in sediment grain size and determine the lithology in clastic reservoirs. However, grain size analysis of modern sedimentary samples collected from active rivers and deltas indicates that the percentage of fine depositional component has a logarithmic relationship with the average grain size in delta and river systems. Using the linear relationship to process the lithology interpretation, siltstones or mudstone is likely to be interpreted as sandstone. Therefore, a logarithmic conversion formula was built up between the gamma ray logs and measured grain size for the second member of the Xujiahe Formation of Anyue Area in the Sichuan Basin. Using the formula, the average grain size and lithology of the exploration wells were determined for the interest intervals. Furthermore, the calculated grain size gives a better understanding of the controlling factors of hydrocarbon-bearing reservoirs in the study area.


2021 ◽  
Vol 10 (23) ◽  
pp. 5622
Author(s):  
Sophie A. Rameckers ◽  
Rogier E. J. Verhoef ◽  
Raoul P. P. P. Grasman ◽  
Wouter R. Cox ◽  
Arnold A. P. van Emmerik ◽  
...  

We examined the effectiveness of psychotherapies for adult Borderline Personality Disorder (BPD) in a multilevel meta-analysis, including all trial types (PROSPERO ID: CRD42020111351). We tested several predictors, including trial- and outcome type (continuous or dichotomous), setting, BPD symptom domain and mean age. We included 87 studies (N = 5881) from searches between 2013 and 2019 in four databases. We controlled for differing treatment lengths and a logarithmic relationship between treatment duration and effectiveness. Sensitivity analyses were conducted by excluding outliers and by prioritizing total scale scores when both subscale and total scores were reported. Schema Therapy, Mentalization-Based Treatment and reduced Dialectical Behavior Therapy were associated with higher effect sizes than average, and treatment-as-usual with lower effect sizes. General severity and affective instability showed the strongest improvement, dissociation, anger, impulsivity and suicidality/self-injury the least. Treatment effectiveness decreased as the age of participants increased. Dichotomous outcomes were associated to larger effects, and analyses based on last observation carried forward to smaller effects. Compared to the average, the highest reductions were found for certain specialized psychotherapies. All BPD domains improved, though not equally. These findings have a high generalizability. However, causal conclusions cannot be drawn, although the design type did not influence the results.


Mathematics ◽  
2021 ◽  
Vol 9 (22) ◽  
pp. 2863
Author(s):  
Napasool Wongvanich ◽  
I-Ming Tang ◽  
Marc-Antoine Dubois ◽  
Puntani Pongsumpun

Hand, foot and mouth disease (HFMD) is a virulent disease most commonly found in East and Southeast Asia. Symptoms include ulcers or sores, inside or around the mouth. In this research, we formulate the dynamic model of HFMD by using the SEIQR model. We separated the infection episodes where there is a higher outbreak and a lower outbreak of the disease associated with regional residency, with the higher level of outbreak occurring in the urban region, and a lower outbreak level occurring in the rural region. We developed two different optimal control programs for the types of outbreaks. Optimal Control Policy 1 (OPC1) is limited to the use of treatment only, whereas Optimal Control Policy 2 (OPC2) includes vaccination along with the treatment. The Pontryagin’s maximum principle is used to establish the necessary and optimal conditions for the two policies. Numerical solutions are presented along with numerical sensitivity analyses of the required control efforts needed as the control parameters are changed. Results show that the time tmax required for the optimal control effort to stay at the maximum amount umax exhibits an intrinsic logarithmic relationship with respect to the control parameters.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Weidong Jin ◽  
Zhe Wang ◽  
Yongming Ai ◽  
Chenyang Liu

The unconfined compressive strength of cement-modified silty sand in Jilin Province was investigated in this study. For this purpose, various tests were conducted, including the screening test, compaction test, CBR test, X-ray fluorescence detection, and unconfined compressive strength test. Effects of compaction degree, soil quality, water quality, cement content, and curing age were considered. The results show that CBR value is positively correlated with compactness. Two kinds of different water qualities have little effect on unconfined compressive strength of cement-improved soil; with the increase in cement content, the unconfined compressive strength increases, and the power function equation established by the two is significantly correlated. The logarithmic relationship between cement-soil strength and curing age is approximately linear. Through regression analysis, the comprehensive characterization parameters of cement-soil strength, such as water-cement ratio, cement content, and curing age, are put forward. The unconfined compressive strength of cement-modified silty sand has a good power function relationship with the comprehensive characterization parameters, and the fitting degree between the strength prediction formula and the existing research and test data exceeds 90%, which verifies the effectiveness of the comprehensive characterization parameters.


2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S102-S103
Author(s):  
M Reno ◽  
C Stefaniuk

Abstract Introduction/Objective The lupus anticoagulant (LA) panel utilizing dilute Russell’s viper venom and LA-responsive APTT remains the front-line screen for detecting the presence of clinically significant antibodies in the diagnosis of antiphospholipid syndrome. Receiving anticoagulant therapy limits the utility of clotting-based methods due to increased risk of false positive results. Anti-cardiolipin (aCL) and anti-ß2-glycoprotein I (a2GßPI) antibody titers have also been employed for the detection of anti-phospholipid antibodies; however, they are not influenced by anticoagulation therapy. The International Society on Thrombosis and Haemostasis recommends that all three tests should be performed to appropriately assess the risk of lupus anticoagulant/antiphospholipid antibodies. In this study, the concordance and discordance of rates of among these three assays were examined. Methods/Case Report The electronic medical record was mined according to lab tests codes for the results of the LA panel, aCL and a2GßPI antibody titers for all patients having at least one resulted study at the University of Cincinnati Medical Center in Cincinnati, Ohio, over a one-year period (2020). Results were compared to determine rates of concordance and discordance among the assays as well as Spearman’s correlation. Non-parametric binary regression analysis was applied to explore the relationship connecting aCL and a2GßPI titers to LA panel findings. Results (if a Case Study enter NA) Strong concordance was seen between the results of LA panels and antibody titer assays. A weak but significant positive correlation was found among the three assays. A robust logarithmic relationship was developed from which the LA panel result could be predicted utilizing outcomes from aCL and a2GßPI antibody titer findings. Conclusion These data further support the reliability of aCL and a2GßPI titers in the evaluation of antiphospholipid syndrome. Furthermore, the robust relationship among these three assays suggests that antibody titers may provide a reliable diagnostic avenue for patients actively undergoing anticoagulation therapy.


2021 ◽  
Author(s):  
Cody A Freas ◽  
Antoine Wystrach ◽  
Sebastian Schwarz ◽  
Marcia A Spetch

Many ant species are able to establish routes between goal locations by learning views of the surrounding visual panorama. Route formation models have, until recently, focused on the use of attractive view memories, which experienced foragers orient towards to return to the nest or known food sites. However, aversive views have recently been uncovered as a key component of route learning. Here, Cataglyphis velox rapidly learned aversive views, when associated with a negative outcome, a period of captivity in brush, triggering an increase in hesitation behavior. These memories were based on the accumulation of experiences over multiple trips with each new experience regulating foragers hesitancy. Foragers were also sensitive to captivity time differences, suggesting they possess some mechanism to quantify duration. Finally, we characterized foragers perception of risky (variable) versus stable aversive outcomes by associating two sites along the homeward route with two distinct schedules, a fixed duration of captivity or a variable captivity duration, with the same mean time over training. Foragers exhibited significantly less hesitation to the risky outcome compared to the fixed, indicating they perceived risky outcomes as less severe. Results align with a logarithmic relationship between captivity duration and hesitation response, suggesting that foragers perception of the aversive stimulus is a logarithm of its actual value. We conclude by characterizing how view memory and risk perception can be executed within the mushroom bodies neural circuitry.


Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 1986
Author(s):  
Xuhan Ding ◽  
Guang Xu ◽  
Dengfei Wang ◽  
Zhenmin Luo ◽  
Tao Wang

The application of polymer colloids is a promising approach for bauxite residue dust pollution control. However, due to the existence of synergistic aging, the efficiency of colloid dynamic viscosity to predict the dust control performance of bauxite residue is unclear. Previous studies were also rarely performed under synergistic aging conditions. Thus, this paper investigates the relationship between colloids’ viscosity and dust control performance under synergistic aging modes. Results illustrated that the binary colloid achieved better dust control performance than unitary colloid for their higher viscosity and penetration resistance. For both unitary and binary colloid, higher viscosity results in better crust strength. A logarithmic relationship was found for viscosity and dust erosion resistance under unitary aging. However, Only the dynamic viscosity of colloids in solid-liquid two-phase conditions, rather than dissolved in deionized water, can effectively predict the dust control performance under synergistic aging conditions.


Cybersecurity ◽  
2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Yiru Sun ◽  
Yanyan Liu

AbstractMessage-dependent opening is one of the solutions to solve the problem of the tracing manager owns excessive power. In this paper, we present a new lattice-based fully dynamic group signature scheme with message-dependent opening by combining an improved version of the fully dynamic group signature scheme proposed by Ling et al and the double encryption paradigm. In addition, we propose an improved underlying zero knowledge protocol, it has a soundness error $\frac {1}{\max (n,p)+1}$ 1 max ( n , p ) + 1 that is better than the Stern-like protocol, which helps to bring down the communication complexity of the protocol and hence the signature scheme. Our scheme constrains the power of group managers by adding an admitter, and the signature size has a logarithmic relationship with the group size.


Author(s):  
Berend Denkena ◽  
Alexander Krödel ◽  
Steffen Heikebrügge ◽  
Kolja Meyer ◽  
Philipp Pillkahn

AbstractDeep rolling is a machining process which is used to decrease roughness and to induce compressive residual stresses into component surfaces. A recent publication of this research group showed possibilities to predict the topography during deep rolling of bars in a lathe. Although deep rolling can be used in a milling machine to machine flat specimens, it is still unclear, whether the topography can be predicted to a similar extend using this application. To investigate the influence of the machining parameters on topography, three experimental stages are performed in this paper on cast AlSi10Mg. First, single-track deep rolling experiments are performed under variation of the deep rolling pressure $$p_w$$ p w to find the relationship between $$p_w$$ p w and the indentation geometry. Here, a logarithmic relationship between deep rolling pressure and the indentation characteristics could be found that achieved a relatively high agreement. In the second stage, surfaces are prepared using multi-track deep rolling. Here, the deep rolling pressure $$p_w$$ p w and the lateral displacement $$a_b$$ a b are varied. The multi-track rolled surfaces were compared to an analytical model for the calculation of the theoretical roughness that is based on the logarithmic relationship found in the first experimental stage. Here, the limits of the analytical prediction were shown because high similarities between predicted and measured surfaces only occurred for certain deep rolling pressures $$p_w$$ p w and lateral displacements $$a_b$$ a b . To further investigate the limitations of this procedure, a novel tool concept, which utilizes the rotation of the machine spindle, is used in the third stage. Here, the generated surface can also be interpreted as a periodic sequence of spheric indentations as shown in the second experimental stage, whereas the measured surfaces differed from the expected surfaces. As a result of this paper, the predictability of the surface topography after deep rolling of flat specimens is known (minimum pressure $$p_{w,minAlSi10Mg}$$ p w , m i n A l S i 10 M g  = 5 MPa and minimum lateral displacement $$a_{b,minAlSi10Mg}$$ a b , m i n A l S i 10 M g  = 0.25 mm) and also first results regarding the final topography after using the novel tool concept are presented.


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