Portion Of Valley Research Articles

Tracking Mississippian Migrations from the Central Mississippi Valley to the Ridge and Valley with a Unified Absolute Chronology

AbstractAs regional chronologies become better defined, we are better able to track large-scale population movements and related cultural change. A dataset of 156 radiocarbon dates from the Middle Cumberland Region (MCR), evaluated with 199 more dates from the Ridge and Valley portions of northern Georgia and East Tennessee, enable modeling of population movements from the Central Mississippi Valley into the MCR, as well as subsequent movements and effects in the Ridge and Valley between AD 1200 and 1450. The dissolution of Cahokia is of particular interest, because the MCR falls geographically between the American Bottom and the Ridge and Valley province. This large-scale chronological perspective places key events in this part of the Southeast and Midwest into a unified historical framework that increases our understanding of the timing of cultural events. A related goal is to sort out possible external events and influences that may have affected this large region. This study makes apparent the relationships between cultural events and natural events, such as the drought sequences reported for the Central Mississippi Valley and beyond.

IMPACTS OF URBANISATION ON ENVIRONMENTAL CHANGE OF ZIRO VALLEY, ARUNACHAL PRADESH

Urbanization is a process of growth of cities and town; which is directly linked to the degradation of environmental quality and the quality of water, air and noise. Ziro valley, the place has an imposing landscape of beautiful lush green forest, rivulets, and elevated patches. It is famous for paddy cum pisciculture cultivation. The area is renowned for the terrace paddy fields where the unique system of poly- culture and water management is practiced by local people. But due to rapidly increase of urban area in Ziro valley, the environment become changed day by day. The purpose of the paper is to present the effects on environment due to urbanization in Apatani society in Ziro valley of Lower Subansiri district of Arunachal Pradesh. There are several areas where urbanization has affected along with environment settings. The induced of development of urbanization which is affected on the balance of the ecosystem in the valley portion. The study based on secondary data, satellite image, photography etc. and primary sources, the study area map has prepared through QGIS

ANN-Based DEM Fusion and DEM Improvement Frameworks in Regions of Assam and Meghalaya using Remote Sensing Datasets

The Digital Elevation Models (DEMs) are a key and primary input to a large number of modelling processes such as disaster risk monitoring, flood modelling, hydrology, geology, geomorphology, climatology, and environmental study applications. The DEM serves as an important source of topographic information representing the continuous surface of the earth in 3 dimensions with x, y and z coordinates of any point in a grided raster form or a vector TIN form. This study is based on developing a new method using the universal approximation capability of neural networks for the fusion and improvement of L-band and X-band SAR (Synthetic Aperture Radar) DEMs in the complex terrain of Assam and Meghalaya states of the Indian geographic region using the DEM fusion technique. The high-spatial-resolution ALOS PALSAR RTC HR 12.5 m DEM products are used in a fusion framework designed with neural network models. The network adaptively learns the terrain information to produce fused DEM products. The neural network models generate the relationship between the input elevation information from ALOS PALSAR DEMs and precise reference elevation from ICESat-2 spaceborne altimetry as target data. The training and testing data samples are prepared and filtered by checking the correct range of elevation from the toposheets of this region. Different models are used to separately train for the relatively plain valley portion of the Assam region and mountainous portions of the highland Shillong plateau. The obtained fused DEMs from the developed neural net structure are assessed for their quality and accuracy by estimating the RMSE parameter. The fused DEM attains an RMSE value of 7 meters for the complete region which is a significant improvement over the input DEM RMSE of approximately 11 meters. The plain area points and mountainous region points are assessed separately to analyze the predictions from neural nets in the two types of terrains observed in this study site. Moreover, TanDEM-X 90 m DEM is improved using the neural network modeling in the geometric distortions affected areas, which shows an improvement of around 33% overall at the study site. The assessment of plain and mountainous region points for near-ground points shows an improvement of 47% and 55% respectively. The fusion framework designed using the neural network models is an effective and efficient method for obtaining fused DEMs as well as for the improvement of the existing DEMs for complex terrain.

Two-Process Random Textures: Measurement, Characterization, Modeling and Tribological Impact: A Review.

Two-process random textures seem to present better functional properties than one-process surfaces. There are many random two-process textures. Plateau-honed cylinder surfaces are the most popular example. Two-process surfaces are also created during the initial periods of life of machined elements. However, knowledge about two-process textures measurement, modeling, and behavior is low. Two-process surfaces are very sensitive to measurement errors. It is very difficult to model them. Special methods of their characterization were created. Their functional significance was studied in a small number of publications. In this paper, measurement, characterization, and modeling of two-process textures were presented. The functional impact of them was analyzed, the effects on contact mechanics and friction and wear were mainly studied. Finally, considerations of future challenges were addressed. The nature of two-process random textures should be taken into account during analyses of properties of machined elements. The plateau part decides about the asperity contact, and the valley portion governs the hydrodynamic lubrication.

Geometrical consideration for mechanical contact between rolling circle and surface roughness as an improvement to the surface profile

This paper describes measurement methods of surface profiles that improve contact-type displacement sensor outputs by focusing on the contact point between the sphere tip of the sensor and the rough surface. We examined the geometry of a surface profile model and compared measurements using various methods with the measurement using a roughness meter. The spherical tip of the contact type displacement sensor touches the measurement surface and detects the displacement. The sphere tip radius of a typical contact-type displacement sensor ranges from 1–3 mm, causing the roughness curve to be “filtered” by the radius of the sphere. Three methods for estimating the valley portion of the surface profile are evaluated in this study: a) linear approximation of the concave portion of the surface profile, b) function approximation of the concave portion, and c) using the known nose radius of the machining tool. The following sphere tip radii were used to measure actual surface profiles: 0.25 mm, 0.5 mm, 1.0 mm and 1.5 mm. Given the conditions of the experimental model, we found that surface profiles with a roughness that approximates a predictable curve can be measured with a high degree of accuracy.

Reinterpreting Models of Slope-Front Recharge in a Desert Basin

Identification of recharge areas in arid basins is challenging due to spatial and temporal variability and complexity of the hydrogeology. This study re-evaluates recharge mechanism in a desert basin where isotopic and geologic data indicated that published conceptual models of recharge are not accurate. A new model of recharge is formulated that is consistent with the unique geologic framework in the basin. In the area of study, the Rio Grande flows across a broad alluvial floodplain, the “El Paso-Juarez Valley”, where the river has incised the surface of the Hueco Bolson. The modern Rio Grande floodplain overlies the older basin fill, or “Hueco Bolson deposits”, in the valley portion of the area. The lateral contact between the older bolson deposits and the recent alluvial floodplain deposits defines the “slope front”. The valley wall along the slope front is penetrated by many arroyos that incise the Hueco Bolson deposits and modern floodplain surface. The presence of a large lens of freshwater at the boundary between the older bolson fill and recent Rio Grande alluvium seemed to suggest to previous researchers that dilute water developed due to runoff drawn in by San Felipe Arroyo, a prominent arroyo at the slope front between the older Hueco Bolson deposits and the recent Rio Grande alluvium. Our follow-up verification work illustrates that this is demonstrably not the case. The testing of groundwater samples for stable water isotopes and radioisotopes showed that the deeper and more dilute waters near San Felipe Arroyo are actually pre-dam waters recharged from the shifting Rio Grande channel.

Bedrock And Boulder Mortars, Basins, Slicks, And Cupules In The Southern Southwest

This article describes mortars, basins, slicks, and cupules created in bedrock and boulders in the Southern Southwest, and discusses the distribution and possible functions of these features. It defines the Southern Southwest as the region of the U.S. south of 34 degrees north latitude that includes the Califor­nia portion of the Lower Colorado River valley and southern portions of Arizona and New Mexico, and the portion of western Texas that includes El Paso, Hudspeth, Culber­son, Loving, Winkler, Ward, Reeves, and Jeff Davis counties (roughly the part of Texas from El Paso eastward just past the south­eastern corner of New Mexico, then south and south­westward to a point south of Fort Davis, then westward to the Río Grande).

Numerical simulation and experimental verification for magnetic field analysis of thread magnetic matrix in high gradient magnetic separation

In this study, based on the characteristics of the rod matrix and the dentate plate magnetic matrix, the thread magnetic matrix is proposed. The numerical simulation technology and model test are utilized to analyze the magnetic field distribution characteristics of the thread magnetic matrix and the effects of structure parameters on magnetic field distribution characteristics are investigated. Firstly, the numerical simulation results indicate that the magnetic induction intensity on the sharp corner of the magnetic matrix is higher, which is inferred to be the magnetic particle adsorption zone, while the valley portion is inferred to be the magnetic particle exclusion zone owing to the low magnetic induction intensity comparing to the sharp corner. Besides, the suitable sharp angle of the magnetic matrix is 60° owing to the high magnetic field force and wide magnetic particle adsorption area and the magnetic particle exclusion zone on the valley region of the threaded magnetic matrix gradually shrink with the increase of the thread pitch and the appropriate thread pitch of the threaded magnetic matrix is 1.0 mm owing to the high magnetic field force. Moreover, the results of the model test indicate that the numerical simulation results are basically consistent with the measured results which prove the numerical simulation results are credible. Furthermore, the adsorption morphology of magnetic particles demonstrates that the magnetic particles are adsorbed on the sharp corner and the magnetic particle exclusion zone in the valley region gradually shrink with the increase of the thread pitch. These results further indicate the inference which the sharp corner of threaded matrix is the adsorption zone of the magnetic particle, while the valley region is the exclusion zone is correct. This study has certain guiding significance for the development of new type magnetic matrices and the application of high gradient magnetic separation technology.

Undulated flooring in the rearing tank decreases hypermelanosis in Japanese flounder Paralichthys olivaceus

In the aquaculture of the Japanese flounder Paralichthys olivaceus, hypermelanosis, a malpigmentation condition in which the scales of a significant area on the blind side express the characteristics of those on the ocular side, remains a major concern. Since introducing sand into the rearing tank effectively suppresses hypermelanosis, the inhibitory effects of various characteristics of the surface of the tank floor were investigated. Although an inhibitory effect was observed in both tanks with a sand-image floor and a sand-pasted floor, the strongest effect was found in tanks with a dimpled floor. In addition, covering the inner surface of the tank with net also inhibited hypermelanosis. Using a commercially available corrugated plate, the inhibition of hypermelanosis was confirmed with a noted increase in this effect when combined with light coloration. Juveniles tended to situate themselves in the valley portions of the corrugated plate, suggesting that floor contact with the blind side may contribute to hypermelanosis inhibition. Further observations on the floor contact area with various floor configurations suggested that hypermelanosis is locally suppressed in the areas with floor contact. Therefore, suppression by an undulated (both dimpled and corrugated) floor is likely due to an increase in floor contact area with the blind side.

Assessment of soil loss by universal soil loss equation (USLE) model using GIS techniques: a case study of Gumti River Basin, Tripura, India

Soil loss is a serious environmental threat in humid sub-tropical State Tripura. The present study is carried out in Gumti River Basin of Tripura State, North East India having an area of 2492 km2. Long term daily rainfall intensity is very high in this region and that’s why sheet erosion of soil is common phenomena. Spatial distribution of soil loss in the study area was estimated by integrating five essential parameters of universal soil loss equation model in GIS mapping platform (mainly ArcGIS 10.1). Those five parameter are runoff–rainfall erosivity factor (R), soil erodibility factor (K), slope length and steepness (LS), cropping management factor (C), and support practice factor (P). In these study ASTER digital elevation model having 30 m resolution and LISS III image have been used for estimation of LS factor and C factor. The daily rainfall data (2001–2010) of seven rain gauge stations located in the Gumti River Basin and its adjoining area have been used to predict the R factor. Predicted average annual soil loss of the basin has been classified into five categories according to intensity level of soil loss. The high rate (>45 t ha−1 year−1) of soil erosion was found along the main course of Gumti River, interhill valley portion and also the flood plain area of the basin, whereas low amount of soil loss (<10 t ha−1 year−1) was found at densely forested areas and intensely plantation area of the basin.

Distinguishing the Plateau and Valley Components of Profiles From Various Types of Two-Process Textures

Abstract This paper presents methods of separating the plateau part for various types of two-process profiles, having the traces of two processes. The traditional method based on the plateau-valley threshold, according to the ISO 13565-3 standard, is not always sufficient, since the valley portion can include plateau roughness. Starting and finishing points of each plateau in the measured profiles should be determined. The procedure found in the technical literature depends on setting not only the plateau-valley threshold but also a lower threshold. This approach was a little modified for profiles that contain both random and deterministic topography components. A new procedure of determination of the lower threshold was proposed for stratified profiles containing two deterministic parts. The valleys can be characterized by their widths and the distance between them. In addition, a description of the material probability curve is proposed.

Adhesion and cleanability of surfaces in the baker's trade

Several surfaces relevant to the baker's trade were evaluated regarding the normal acceleration needed to remove either wheat flour particles or wheat dough using the centrifuge method. The findings were compared to surface properties and parameters derived by CLSM measurements. Stainless steel sheets of different roughness were found to be strongly adhesive. Conveyor belts appeared to be easily assessable regarding dough adhesion on a visual basis: Shiny surfaces adhere strongest and values scatter the widest, macroscopically structured bands gave lowest and steadiest tensile strength. In proving cloths the critical surface element for dedusting was found to be the valley portion, for easy dough separation it was the maximum height of the surface profile peaks. In both cases cotton appeared to adhere less compared to polyester. Requirements can be accommodated to optimize textiles in use in the baking industry.

Mars Science Laboratory Curiosity Rover Megaripple Crossings up to Sol 710 in Gale Crater

After landing in Gale Crater on August 6, 2012, the Mars Science Laboratory Curiosity rover traveled across regolith‐covered, rock‐strewn plains that transitioned into terrains that have been variably eroded, with valleys partially filled with windblown sands, and intervening plateaus capped by well‐cemented sandstones that have been fractured and shaped by wind into outcrops with numerous sharp rock surfaces. Wheel punctures and tears caused by sharp rocks while traversing the plateaus led to directing the rover to traverse in valleys where sands would cushion wheel loads. This required driving across a megaripple (windblown, sand‐sized deposit covered by coarser grains) that straddles a narrow gap and several extensive megaripple deposits that accumulated in low portions of valleys. Traverses across megaripple deposits led to mobility difficulties, with sinkage values up to approximately 30% of the 0.50 m wheel diameter, resultant high compaction resistances, and rover‐based slip up to 77%. Analysis of imaging and engineering data collected during traverses across megaripples for the first 710 sols (Mars days) of the mission, laboratory‐based single‐wheel soil experiments, full‐scale rover tests at the Dumont Dunes, Mojave Desert, California, and numerical simulations show that a combination of material properties and megaripple geometries explain the high wheel sinkage and slip events. Extensive megaripple deposits have subsequently been avoided and instead traverses have been implemented across terrains covered with regolith or thin windblown sand covers and megaripples separated by bedrock exposures.

Evaluation of the ornithogenic influence on the trophic state of East Mediterranean wetland ecosystem using trend analysis

The Great Rift Valley portion of the East African–Eurasian Migratory Flyway is extremely important globally because of the numbers (>500 million) and diversity of seasonal traveling birds. The construction of the Agmon wetland (1.1km2) in the Hula Valley, Israel in 1994 and a change in crop type and rotation has attracted increasing number of Eurasian cranes (Grus grus) to winter in the wetland (>40,000 in 2014). The birds are fed in an area of 100ha and roost during the night in the wetland for protection from predators. Feeding practices have yielded an eco-tourism bonanza with over 400,000 visitors annually. However, this practice may have negative impacts on the trophic state of the wetland. We performed trend analyses using monthly means of selected constituents collected from mid-1994 to 2014. The temporal distribution of TN and TP concentrations in the inlets did not change with time. The concentrations of TN and TP in the outlet increased significantly during the earlier monitoring period. Kendall–Theil regression showed that TP concentrations in the outlet increased significantly from a monthly mean of 180μgL−1 in 2010 to a monthly mean of 260μgL−1 in 2014. Similarly, the results of chlorophyll a concentrations in the outlet showed a sharp upturn in the latter part of the series from a mean of 66mgL−1 in 2010 to a mean of 122mgL−1 in 2014. The concurrent increase of TP and chlorophyll a, the two most important parameters affecting a waterbody trophic index coincided with the observed increase in the number of roosting cranes in the wetland. Hence, we assume that the continued increases in TP concentrations could transform the wetland from a mild eutrophic to a permanent hypereutrophic state. Reducing the number of roosting cranes may prevent this from happening.

Integrated hazard assessment of Cirenmaco glacial lake in Zhangzangbo valley, Central Himalayas

Glacial lake outburst floods (GLOFs) have recently become one of the primary natural hazards in the Himalayas. There is therefore an urgent need to assess GLOF hazards in the region. Cirenmaco, a moraine-dammed lake located in the upstream portion of Zhangzangbo valley, Central Himalayas, has received public attention after its damaging 1981 outburst flood. Here, by combining remote sensing methods, bathymetric survey and 2D hydraulic modeling, we assessed the hazard posed by Cirenmaco in its current status. Inter-annual variation of Cirenmaco lake area indicates a rapid lake expansion from 0.10±0.08km2 in 1988 to 0.39±0.04km2 in 2013. Bathymetric survey shows the maximum water depth of the lake in 2012 was 115±2m and the lake volume was calculated to be 1.8×107m3. Field geomorphic analysis shows that Cirenmaco glacial lake is prone to GLOFs as mass movements and ice and snow avalanches can impact the lake and the melting of the dead ice in the moraine can lower the dam level. HEC-RAS 2D model was then used to simulate moraine dam failure of the Cirenmaco and assess GLOF impacts downstream. Reconstruction of Cirenmaco 1981 GLOF shows that HEC-RAS can produce reasonable flood extent and water depth, thus demonstrate its ability to effectively model complex GLOFs. GLOF modeling results presented can be used as a basis for the implementation of disaster prevention and mitigation measures. As a case study, this work shows how we can integrate different methods to GLOF hazard assessment.

Isolines of location specific constants of rainfall intensity- duration- frequency for Vidarbha region

Rainfall intensity-duration-frequency (IDF) relationship is required for design of soil and water conservation structures. Rainfall intensity-duration-frequency relation depends on the physical characteristics of rainfall occurring at a particular place. The rainfall intensity-duration-frequency relationship can be expressed as I = (KT a )/(t + b) d in which, I is rainfall intensity (cm/h), T is return period (years), t is duration (h) and K, a, b and d are location specific constants. The location specific constants in above relationship are calculated by analyzing the rainfall data of recording type rain gauge. The values of K, a, b and d are estimated for all stations of Vidarbha region. Then isolines maps of each constant K, a, b and d for Vidarbha region have been developed. Isoline for 'a' show steeper increase in western Vidarbha with minimum in Nagpur district. The values of constant 'a' vary from 0.1544 to 0.2074 in all nine stations except Buldhana (0.2524). As far as constant 'b' is concerned the isolines show valley portion from Amravati towards Akola i.e. in western direction. The common range of the values of constant 'b' varies from 0.20 to 0.30. The isolinesfor'd' showed concentric circles in western Vidarbha near Akola and similar type is observed near Nagpur. The common range of constant 'd' is in between 0.6618 to 0.7668. There was no general slope for isolines of 'd'. The isoline for 'K' showed two concentric circles around Nagpur and Akola denoting two peaks and in general has slopes in North-East direction from Akola and Nagpur. The 'K' value for Vidarbha range from 3.148 to 6.680. Isolines maps developed for different parameters of intensity-duration-frequency equation of Vidarbha region are useful to designers and planners for prediction of rainfall intensity at any location of Vidarbha region for any duration up to 24 hour and return period from 10 to 100 years to design flood control, rainwater harvesting and runoff disposal structures.

Combining forces--the use of Landsat TM satellite imagery, soil parameter information, and multiplex PCR to detect Coccidioides immitis growth sites in Kern County, California.

Coccidioidomycosis is a fungal disease acquired through the inhalation of spores of Coccidioides spp., which afflicts primarily humans and other mammals. It is endemic to areas in the southwestern United States, including the San Joaquin Valley portion of Kern County, California, our region of interest (ROI). Recently, incidence of coccidioidomycosis, also known as valley fever, has increased significantly, and several factors including climate change have been suggested as possible drivers for this observation. Up to date details about the ecological niche of C. immitis have escaped full characterization. In our project, we chose a three-step approach to investigate this niche: 1) We examined Landsat-5-Thematic-Mapper multispectral images of our ROI by using training pixels at a 750 m×750 m section of Sharktooth Hill, a site confirmed to be a C. immitis growth site, to implement a Maximum Likelihood Classification scheme to map out the locations that could be suitable to support the growth of the pathogen; 2) We used the websoilsurvey database of the US Department of Agriculture to obtain soil parameter data; and 3) We investigated soil samples from 23 sites around Bakersfield, California using a multiplex Polymerase Chain Reaction (PCR) based method to detect the pathogen. Our results indicated that a combination of satellite imagery, soil type information, and multiplex PCR are powerful tools to predict and identify growth sites of C. immitis. This approach can be used as a basis for systematic sampling and investigation of soils to detect Coccidioides spp.

Description of two-process surface topography

After two machining processes, a large number of surface topography measurements were made using Talyscan 150 stylus measuring equipment. The measured samples were divided into two groups. The first group contained two-process surfaces of random nature, while the second group used random-deterministic textures of random plateau parts and portions of deterministic valleys. For comparison, one-process surfaces were also analysed. Correlation and regression analysis was used to study the dependencies among surface texture parameters in 2D and 3D systems. As the result of this study, sets of parameters describing multi-process surface topography were obtained for two-process surfaces of random and of random-deterministic types.

Nocturnal field use by fall migrating American woodcock in the Delta of Arkansas

ABSTRACTThe American woodcock (Scolopax minor) population has declined since the late 1960s across its range and is now considered a species of special concern. Research on woodcock habitat use during migration and migratory routes through the Central Flyway has been limited. We assessed woodcock phenology, estimated density, and nocturnal habitat use in fields on public lands in the lower Mississippi Alluvial Valley portion of Arkansas during November and December of 2010 and 2011. We used all‐terrain vehicles to survey woodcock along transects in 67 fields of 8 field types. We analyzed data using hierarchical distance sampling. We detected woodcock from the first week in November through the third week in December but in low numbers. We did not detect woodcock in millet or rice fields, whereas woodcock had the highest estimated densities in unharvested soybeans. All other crop type–post‐harvest management combinations had low woodcock densities. We did not detect woodcock in fields &lt;8 ha or &gt;40 ha. Woodcock in the lower Mississippi Alluvial Valley may benefit from management for unharvested soybean fields of moderate size (approx. 8–40 ha). © 2014 The Wildlife Society.

Role of relative size of asperities and adhering particles on the adhesion force

Adhesion force between silica microspheres of different sizes and different rough surfaces (silicon and diamond like carbon) has been measured with an atomic force microscope (AFM). Surface roughness, asperity geometry, and size of adhering particles play an important role in determining the adhesion force. Adhesion force linearly increases with size of adhering particle for smooth surfaces and can be described by the JRK model. Adhesion force of adhering particle bigger than in size to the asperities decreases with surface roughness and can be described by the Rabinovich model. For the particles smaller than or similar in size to the asperities, the adhesion force increases with surface roughness. In later case, the interaction of adhering particles with valley portion of asperities is dominated and the contact area increases. On the basis of Rabinovich model, a new equation, which takes the relative size of adhering particles and asperities into account, is derived and compared with experimental results. The normalized adhesion force decreases with ratio of root-mean-square (rms) roughness to radius of adhering particle up to 0.0025, followed by increasing normalized adhesion forces.