Earthen architecture in the Mesoamerican classic period: A micromorphological approach to its manufacture process

AbstractRecent excavations at Tula Chico, the monumental center for Tula's earliest settlement, revealed a long and complex history of occupation, beginning with its initial settlement in the Middle Classic period by Coyotlatelco peoples, when much of the region was under Teotihuacan's direct control. During the Epiclassic period, a program of monumental construction began that developed the monumental complex seen today over a period of about 200 years. Although Tula Chico was superseded by Tula Grande, the monumental center for the Early Postclassic city, it continued to be occupied and maintained until its destruction by fire. Tula Chico and Tula Grande show evidence of clear cultural continuity in ceramics, architecture, and sculpture, including “Toltec style” sculpture characteristic of Tula Grande that is present in temporally early contexts at Tula Chico.

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Fluid–Structure Coupling Effects in a Dual U-Tube Coriolis Mass Flow Meter

Sensors ◽

10.3390/s21030982 ◽

2021 ◽

Vol 21 (3) ◽

pp. 982

Author(s):

Yuh-Chung Hu ◽

Zen-Yu Chen ◽

Pei-Zen Chang

Keyword(s):

Product Design ◽

Dynamic Balance ◽

Fluid Viscosity ◽

Fluid Structure ◽

Development Platform ◽

Design Considerations ◽

Manufacture Process ◽

Coupling Dynamics ◽

Comsol Simulation ◽

Important Design

Coriolis mass flowmeters are highly customized products involving high-degree fluid-structure coupling dynamics and high-precision manufacture. The typical delay from from order to shipment is at least 4 months. This paper presents some important design considerations through simulation and experiments, so as to provide manufacturers with a more time-efficient product design and manufacture process. This paper aims at simulating the fluid-structure coupling dynamics of a dual U-tube Coriolis mass flowmeter through the COMSOL simulation package. The simulation results are experimentally validated using a dual U-tube CMF manufactured by Yokogawa Co., Ltd. in a TAF certified flow testing factory provided by FineTek Co., Ltd. Some important design considerations are drawn from simulation and experiment. The zero drift will occur when the dual U-tube structure is unbalanced and therefore the dynamic balance is very important in the manufacturing of dual U-tube CMF. The fluid viscosity can be determined from the driving current of the voice coil actuator or the pressure loss between the inlet and outlet of CMF. Finally, the authors develop a simulation application based on COMSOL’s development platform. Users can quickly evaluate their design through by using this application. The present application can significantly shorten product design and manufacturing time.

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Study on the Temperature Field of Casting Process in ANSYS

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.2-3.856 ◽

2011 ◽

Vol 2-3 ◽

pp. 856-860

Author(s):

Chang Li ◽

Guang Bing Zhao ◽

Shu Yu Zhang ◽

Xing Han

Keyword(s):

Temperature Field ◽

Casting Process ◽

Interface Temperature ◽

Field Change ◽

Ansys Software ◽

Heat Process ◽

Manufacture Process ◽

Composite Interface ◽

Non Linear ◽

Changing Process

Cast molding is the main manufacture process in foundry, because the most disfigurements occurs in this step, while the foundry itself is a complex non-linear instantaneous transferring heat process, in which it should take the absorbing and releasing potential heat into account. In this paper, it simulates the temperature field changing process of the cast solidification in ANSYS software, gets the temperature field change rule for a typical cast, and analyzed the effect of different foundry technics parameters on composite interface temperature, which will provide numerical bases for optimizing foundry technics parameters in future.

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Drought, agricultural adaptation, and sociopolitical collapse in the Maya Lowlands

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1419133112 ◽

2015 ◽

Vol 112 (18) ◽

pp. 5607-5612 ◽

Cited By ~ 72

Author(s):

Peter M. J. Douglas ◽

Mark Pagani ◽

Marcello A. Canuto ◽

Mark Brenner ◽

David A. Hodell ◽

...

Keyword(s):

Carbon Isotope ◽

Sediment Cores ◽

Classic Period ◽

Maya Lowlands ◽

Agricultural Adaptation ◽

Terminal Classic ◽

Paleoclimate Records ◽

Early Classic Period ◽

Plant Wax ◽

Terminal Classic Period

Paleoclimate records indicate a series of severe droughts was associated with societal collapse of the Classic Maya during the Terminal Classic period (∼800–950 C.E.). Evidence for drought largely derives from the drier, less populated northern Maya Lowlands but does not explain more pronounced and earlier societal disruption in the relatively humid southern Maya Lowlands. Here we apply hydrogen and carbon isotope compositions of plant wax lipids in two lake sediment cores to assess changes in water availability and land use in both the northern and southern Maya lowlands. We show that relatively more intense drying occurred in the southern lowlands than in the northern lowlands during the Terminal Classic period, consistent with earlier and more persistent societal decline in the south. Our results also indicate a period of substantial drying in the southern Maya Lowlands from ∼200 C.E. to 500 C.E., during the Terminal Preclassic and Early Classic periods. Plant wax carbon isotope records indicate a decline in C4 plants in both lake catchments during the Early Classic period, interpreted to reflect a shift from extensive agriculture to intensive, water-conservative maize cultivation that was motivated by a drying climate. Our results imply that agricultural adaptations developed in response to earlier droughts were initially successful, but failed under the more severe droughts of the Terminal Classic period.

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Changing Patterns of Ritual Activity in an Unlooted Cave in Central Guatemala

Latin American Antiquity ◽

10.7183/1045-6635.23.1.93 ◽

2012 ◽

Vol 23 (1) ◽

pp. 93-119 ◽

Cited By ~ 6

Author(s):

Brent K.S. Woodfill ◽

Stanley Guenter ◽

Mirza Monterroso

Keyword(s):

Classic Period ◽

Late Classic ◽

Interregional Trade ◽

Terminal Classic ◽

Changing Patterns ◽

Ritual Activity ◽

Trade Route ◽

Northern Highlands

AbstractThe Cave of Hun Nal Ye, located in central Guatemala, was discovered unlooted by a local landowner in 2005 and was immediately subject to investigation by the authors. The cave contained ritual remains dating to between the Terminal Pre-classic and Terminal Classic. In addition to allowing a detailed reconstruction of ritual activity in the northern highlands, its presence along the Great Western Trade Route allows archaeologists to examine hypotheses about interregional trade during the Classic period. In particular, changes in the ritual assemblage between the Early and Late Classic indicate that the cave was an important trade shrine for merchants and travelers passing between the highlands and lowlands until ca. A.D. 550, at which point it became a local shrine used to reinforce elite power. These changes are then linked to larger patterns occurring in other parts of the trade route, especially to Tikal and the kingdoms along the Pasión and Usumacinta rivers.

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