Analysis of Surface Runoff

A mathematical model of surface runoff is presented which is of use in building a model of erosion processes. The method used for deriving the conceptual model of surface runoff is based on the mathematical expression of the basic laws of movement of water -- the equation of continuity and the equation of motion. Both equations form a system of nonlinear partial differential equations with two unknown functions expressing the depth and velocity of the movement of water along the slope, in dependence on their location on the slope, and time. The input variables of the model are the intensity and direction of the impinging raindrops, the intensity of infiltration and the physical characteristics of the slope (gradient, length and properties of soil surface). Extensive laboratory experiments have been carried out to determine the functional dependence of tangential stress on the depth and rate of runoff from different types of soil surfaces. Further, the conceptual model of surface runoff has been simplified to a kinematic one by using a simple relation between depth and rate of surface runoff instead of the equation of motion. Two empirical parameters of this relation have been determined by using data from the above mentioned laboratory experiments during calibration of the kinematic model. The kinematic model is recommended because of its simplicity with regard to simulation of the surface runoff formation from individual slopes within the watershed. The model is a multipurpose one. It may be used either for hydrological purposes (simulation of surface runoff characteristics) or for soil conservation purposes. The model outputs are surface characteristics (depth, velocity, rate). It is possible by comparing the surface runoff velocity with the critical nonscouring velocity for given field conditions to determine the critical slope length which is the basis for planning efficient soil conservation measures

Erosion and Water Quality as Modeled by Creams: A Case Study of the Sedlicky Catchment

In the process of verifying and validating the models of agricultural nonpoint source pollution at IIASA, a study was made of the Sedlicky brook (Bohemia, Czechoslovakia) case. The CREAMS model, verified at the Samsin research area (Czechoslovakia) has been used as the mathematical instrument. The validation results of the CREAMS model for the boundary conditions between the field level and the watershed level seem to show that under certain conditions, it can be applied to small watersheds. For large watersheds, modification of the hydrology submodel is necessary in order to describe the comprehensive hydrologic phenomena, particularly, the interflow and some of the subsurface flow

Procedures, Numerical Parameters and Coefficients of the Creams Model: Application and Verification in Czechoslovakia

Problems of agricultural nonpoint source pollution have been investigated by the Resources and Environment Area (Task 2) at IIASA. The CREAMS model has been used as a mathematical aid to arrive at an in-depth understanding of erosion and to predict its influence on agriculture. The CREAMS model was created using data from North America. Investigations of its general use and verification under various conditions were useful. This paper summarizes the results of the verification of this model in a research area in Czechoslovakia and focuses attention on certain points which must be carefully considered during application of this model

The processing, properties and use of the pyrotechnic mixture-titanium subhydride/potassium perchlorate

Development of this pyrotechnic occurred because of the need for a static insensitive material to meet personnel safety requirements and related system safety issues in nuclear weapon energetic material component designs. Ti subhydride materials are made by the thermal dehydrding of commercial Ti hydride powder to the desired equivalent hydrogen composition in the Ti lattice. These Ti subhydrides, when blended with K perchlorate, meet the static insensitivity requirement of not being initiated from an equivalent human body electrostatic discharge. Individual material and blend qualification requirements provide a reproducible material from lot to lot. These pyrotechnic formulations meet the high reliability requirements (0.9995) for initiation and performance parameters and have the necessary stability and compatibility to meet long lived requirements of more than 25 years. Various experiences and problems are also discussed that have led to a mature technology for Ti subhydride/K perchlorate during its use in energetic material component designs

Interface sharpening in CoFeB magnetic tunnel junctions

We report grazing incidence x-ray scattering evidence for sharpening of the interface between amorphous Co60Fe20B20 and AlOx during in situ annealing below the Co60Fe20B20 crystallization temperature. Enhancement of the interference fringe amplitude in the specular scatter and the absence of changes in the diffuse scatter indicate that the sharpening is not a reduction in topological roughness but a reduction in the width of the chemical composition profile across the interface. The temperature at which the sharpening occurs corresponds to that at which a maximum is found in the tunneling magnetoresistance of magnetic tunnel junctions

Perbandingan Abbott Real-time High-risk HPV dan Cobas 4800 HPV Test untuk Deteksi Molekuler HPV pada Sampel Indonesia

Based on the results of 2013 National Basic Health Research (Riskesdas 2013), as many as 10.3% of female death due to cancer in Indonesia caused by cervical cancer of Human Papillomavirus (HPV) became the main risk factor that was 99.7%. The incidence of cervical cancer can be prevented through early detection of HPV infection moleculary. This study aims to evaluate the ability of Abbot Real-time High-risk HPV (AR) and Roche Cobas HPV (CB) techniques to detect HPV DNA from Indonesia‘s Stored Biology. Furthermore, the results from both techniques are confirmed by using genotyping method using Linnear Array (LA). A total of 74 speciment of stored biological materials (BBT) of cervical swabs stored in Phosphate Buffered Saline (PBS) media were extracted using a special isolation kit from Abbott Real-time High-risk HPV, Cobas 4800 Human Papillomavirus Test and Linear Array. Concentration and purity of HPV viral DNA extraction results were measured by spectophotometry method. The amplification of the extraction results was carried by using a specific primer segment of the L1 gene as a target for detecting HPV DNA. The quality of HPV DNA extraction results using AR technique was 10-30 ng/μL concentration in average, the result was higher when compared to the CB technique which only range from 10-20 ng/μL, but the results using the LA technique had a concentration ≥ 30 ng/μL in average. The purity of HPV DNA extraction using AR and CB technique was similar more or less. The examination of 74 samples had found HPV 16, HPV 18, and other HPV type in each technique, which were 14 positive (9, 4, and 1) in AR technique, 5 positive (3,2, and 0) in CB technique, and 14 positive (8, 4, and 2) in LA technique. AR technique is more accurate and optimal than CB technique in detecting HPV virus and identifying HPV virus types. Both AR and CB technique have their own advantages and disadvantages, although they have uses an automated system of isolation and readout results analysis. It could be concluded that AR technique has better performance in detecting HPV when compared to CB technique

Potensi Resistensi Virus HIV-1 terhadap Terapi Anti Retroviral (ART) pada Pasien Voluntary Counseling And Testing (VCT) di Beberapa Kota di Indonesia

Human Immunodeficiency Virus (HIV) is a virus that damages the immune system. The use of antiretroviraltherapy drugs combination (ARV) has demonstrated highly effective in controlling thedevelopment of the HIV virus and prolongs survival. Comprehensive coverage of antiretroviral therapy(ART) also has an impact on the incidence of mutations in the HIV virus that can lead to resistance. Ingeneral, resistance to a particular drug is the result of a mutation in a number of positions in the proteincodinggenes that are targeted by drugs. This study is aimed to find out mutations that related to ARVresistance in some cities in Indonesia. Genotypic assays are used in this study to analyze the viralresistance properties. The samples are from stored biological materials in the Center for Biomedicaland Basic Technology of Health. One hundred and eightspecimens that meet the inclusion criteriawere amplified and sequenced. Further analysis is conducted by uploading sequences to the StanfordUniversity website for the analysis of resistance mutations. Based on the results of this study there aresome mutations in the HIV virus that leads to a low potential of antiretroviral drug resistance of efavirenz(EFV) and nevirapine (NVP). These drugs are used in the first-line treatment of HIV in Indonesia.Overview of the mutations that cause viral resistance to antiretroviral drugs with genetic methods isexpected to serve as baseline data for program development of new drugs or vaccines HIV / AIDS inthe response to HIV in Indonesia

Multiple-stable anisotropic magnetoresistance memory in antiferromagnetic MnTe

Commercial magnetic memories rely on the bistability of ordered spins in ferromagnetic materials. Recently, experimental bistable memories have been realized using fully compensated antiferromagnetic metals. Here we demonstrate a multiple-stable memory device in epitaxial MnTe, an antiferromagnetic counterpart of common II–VI semiconductors. Favourable micromagnetic characteristics of MnTe allow us to demonstrate a smoothly varying zero-field antiferromagnetic anisotropic magnetoresistance (AMR) with a harmonic angular dependence on the writing magnetic field angle, analogous to ferromagnets. The continuously varying AMR provides means for the electrical read-out of multiple-stable antiferromagnetic memory states, which we set by heat-assisted magneto recording and by changing the writing field direction. The multiple stability in our memory is ascribed to different distributions of domains with the Neel vector aligned along one of the three magnetic easy axes. The robustness against strong magnetic field perturbations combined with the multiple stability of the magnetic memory states are unique properties of antiferromagnets