scholarly journals Experimental Archaeology Study on the Drilling Techniques of Neolithic Stone Bracelet from Purbalingga

KALPATARU ◽  
2021 ◽  
Vol 30 (2) ◽  
pp. 153-166
Author(s):  
Priyatno Hadi Sulistyarto ◽  
Lilin Kumala Pratiwi ◽  
Aldhi Wahyu Pratama ◽  
Salma Fitri Kusumastuti ◽  
Indah Asikin Nurani ◽  
...  

Abstract. The stone bracelet is a neolithic artifact crafted by drilling techniques. Traces of stone bracelet workshop activities in Central Java were found in Purbalingga, which is spread across the North Serayu Mountains between Kali Tungtunggunung and Kali Laban. This study is based on the previous research hypothesis, which states that the manufacture of stone bracelets is carried out by drilling techniques using bamboo wulung (Gigantochloa atroviolacea). This study aims to prove this hypothesis. An experimental archaeological approach by conducting drilling experiments using several drill bits: iron drills, masonry/concrete iron drills, iron drills for natural stone, and bamboo drills. Meanwhile, the abrasive materials used are water, river sand, and quartz sand. The analysis was carried out by comparing the morphological and morphometric traces of the workings between artifacts and experimental results, based on microscopic observations with a magnification of 20x to 200x. Compared to the other drilling bits and abrasive materials, the experimental study revealed that bamboo drill bits, with quartz-sand and water as additional gritty material, showed the closest similarity.

1993 ◽  
Vol 8 (9) ◽  
pp. 2344-2353 ◽  
Author(s):  
J-M. Berthelot ◽  
Souda M. Ben ◽  
J.L. Robert

The experimental study of wave attenuation in concrete has been achieved in the case of the propagation of plane waves in concrete rods. Different mortars and concretes have been investigated. A transmitter transducer coupled to one of the ends of the concrete rod generates the propagation of a plane wave in the rod. The receiver transducer, similar to the previous one, is coupled to the other end of the rod. The experimental results lead to an analytical expression for wave attenuation as function of the concrete composition, the propagation distance, and the wave frequency.


Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1899
Author(s):  
Tae-Yeob Kim ◽  
Sung-Won Yoon ◽  
Ji-Hoon Kim ◽  
Myung-Hyun Kim

The aim of this study is to investigate the applicability of automatic plasma arc welding (PAW) to cryogenic materials used in liquefied natural gas (LNG) fuel storage tanks based on experimental data. The mechanical properties of the materials were tested at room and cryogenic temperatures to investigate the fatigue and fracture performances of weld joints made by PAW. In addition, the influence of welding parameters on the welded joints such as material types and temperature were considered in this experimental study. Based on the results obtained by this experimental study, it was observed that the experimental results of all materials at room and cryogenic temperatures satisfied all the requirements of each mechanical test. Finally, we propose the experimental results of PAW that can be used in the structural design of LNG fuel storage tank applications.


1972 ◽  
Vol 50 (10) ◽  
pp. 2015-2026 ◽  
Author(s):  
David Penny

The typical growth rate curve of the response of lupin hypocotyl to auxin is discussed and explanations suggested for the different parts of the curve. Two alternatives are shown to be able to account for the latent period after auxin addition. One is a linear series of compartments with the transport between compartments similar to allosteric activation in enzyme kinetics and the other alternative is an unmixed compartment (transport delay). Computer simulation is used to test different models to determine whether any model quantitatively predicts the observed results. An example (and variations) of a model is given that predicts much of the experimental results. The model is tested under different conditions such as the addition of different concentrations of auxin, and different times of cycloheximide pretreatment, and on removal from different auxin concentrations. The results of the computer simulations are then compared with experimental results and the model improved to overcome discrepancies. The usefulness of computer simulation in an experimental study is discussed.


Author(s):  
Wojciech Rostworowski ◽  
Katarzyna Kuś ◽  
Bartosz Maćkiewicz

AbstractIn this paper, we present two experimental studies on reference of complex demonstratives. The results of our experiments challenge the dominant view in philosophy of language, according to which demonstrative reference is determined by the speaker's intentions. The first experiment shows that in a context where there are two candidates for the referent—one determined by the speaker’s intention, the other by some “external” factors—people prefer to identify the referent of a demonstrative with the latter object. The external factors for which this prediction has been confirmed include the speaker’s demonstration and the descriptive content of a demonstrative. The second experiment shows that while this preference can be explained in terms of the speakers’ having different sorts of referential intentions, the relevant kind of intentions are fully opaque to the subjects. At the end of our paper, we point to some alternative accounts of demonstrative reference, including a pluralistic and hybrid approach, which can accommodate our experimental results.


2018 ◽  
Vol 52 (2) ◽  
pp. 455-462 ◽  
Author(s):  
G. Ya. Doroshina ◽  
I. A. Nikolajev

Sphagnum mires on the Greater Caucasus are rare, characterized by the presence of relict plant communities of glacial age and are in a stage of degradation. The study of Sphagnum of Chefandzar and Masota mires is carried out for the first time. Seven species of Sphagnum are recorded. Their distribution and frequency within the North Caucasus are analyzed. Sphagnum contortum, S. platyphyllum, S. russowii, S. squarrosum are recorded for the first time for the study area and for the flora of North Ossetia. The other mosses found in the study area are listed.


2018 ◽  
Vol 69 (10) ◽  
pp. 2913-2915
Author(s):  
Daniela Jumanca ◽  
Anamaria Matichescu ◽  
Atena Galuscan ◽  
Laura Cristina Rusu ◽  
Cornelia Muntean

This experimental study aims to analyse the effectiveness of various materials used in demineralisation of dental enamel. This work aims to create a mechanical bond by filling the pegs with sealing material. In order to achieve this goal, five teeth were compared using different concentrations of orthophosphoric acid and exposure times. In this regard, five different tests were performed and the results were analysed using the SEM technique (scanning electron microscopy). These comparative analyses revealed that etching using 35% orthophosphoric acid for one minute and etching using Icon Etch for two minutes were the most effective.


2018 ◽  
Vol 69 (2) ◽  
pp. 305-309 ◽  
Author(s):  
Daniela Gitea ◽  
Simona Vicas ◽  
Manuel Alexandru Gitea ◽  
Sebastian Nemeth ◽  
Delia Mirela Tit ◽  
...  

Our study compares the content in polyphenolic compounds and hypericin, in four species of Hypericum - H. perforatum L., H. maculatum Cr., H. hirsutum L., H. tetrapterum Fr. (syn. Hypericumacutum Mnch.) harvested from spontaneous flora in the north-western area of Transylvania, Romania. These species represent an important source of such compounds with different biological actions. After making the extracts, they were subjected to HPLC-SM analysis. The presence of rutoside in the largest amount (462.82 mg %) in the H. perforatum extract was observed, this containing most of the flavonoid heterosides. For the species H. maculatum, the presence in a much higher amount of the hyperoside (976.36 mg %) is characteristic compared to the other species. Quercetol is the best represented of the flavonoid aglycons, its concentration being the highest in H. hirsutum (659.66 mg %). The hypericin content ranges from 0.2171 g % in the H. tetrapterum extract, to 0.0314 g % in the methanol extract of H. maculatum.The highest antioxidant properties measured by FRAP method were recorded in the case of H. perforatum and H. maculatum.


1994 ◽  
Vol 29 (4) ◽  
pp. 127-132 ◽  
Author(s):  
Naomi Rea ◽  
George G. Ganf

Experimental results demonstrate bow small differences in depth and water regime have a significant affect on the accumulation and allocation of nutrients and biomass. Because the performance of aquatic plants depends on these factors, an understanding of their influence is essential to ensure that systems function at their full potential. The responses differed for two emergent species, indicating that within this morphological category, optimal performance will fall at different locations across a depth or water regime gradient. The performance of one species was unaffected by growth in mixture, whereas the other performed better in deep water and worse in shallow.


Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 307
Author(s):  
Makoto Inoue ◽  
Atsushi Ugajin ◽  
Osamu Kiguchi ◽  
Yousuke Yamashita ◽  
Masashi Komine ◽  
...  

In this study, we investigated the effects of the Tibetan High near the tropopause and the North Pacific High in the troposphere on occurrences of hot or cool summers in Japan. We first classified Japan into six regions and identified hot and cool summer years in these regions from a 38-year sample (1980–2017) based on the monthly air temperature. To investigate the features of circulation fields over Asia during hot and cool summers in Japan, we calculated the composite differences (hot summer years minus cool summer years) of several variables such as geopotential height, which indicated significant high-pressure anomalies in the troposphere and lower stratosphere. These results suggest that both the North Pacific and the Tibetan Highs tend to extend to Japan during hot summer years, while cool summers seem to be associated with the weakening of these highs. We found that extension of the Tibetan High to the Japanese mainland can lead to hot summers in Northern, Eastern, and Western Japan. On the other hand, hot summers in the Southwestern Islands may be due to extension of the Tibetan High to the south. Similarly, the latitudinal direction of extension of the North Pacific High is profoundly connected with the summer climate in respective regions.


2021 ◽  
Vol 40 (1) ◽  
pp. 551-563
Author(s):  
Liqiong Lu ◽  
Dong Wu ◽  
Ziwei Tang ◽  
Yaohua Yi ◽  
Faliang Huang

This paper focuses on script identification in natural scene images. Traditional CNNs (Convolution Neural Networks) cannot solve this problem perfectly for two reasons: one is the arbitrary aspect ratios of scene images which bring much difficulty to traditional CNNs with a fixed size image as the input. And the other is that some scripts with minor differences are easily confused because they share a subset of characters with the same shapes. We propose a novel approach combing Score CNN, Attention CNN and patches. Attention CNN is utilized to determine whether a patch is a discriminative patch and calculate the contribution weight of the discriminative patch to script identification of the whole image. Score CNN uses a discriminative patch as input and predict the score of each script type. Firstly patches with the same size are extracted from the scene images. Secondly these patches are used as inputs to Score CNN and Attention CNN to train two patch-level classifiers. Finally, the results of multiple discriminative patches extracted from the same image via the above two classifiers are fused to obtain the script type of this image. Using patches with the same size as inputs to CNN can avoid the problems caused by arbitrary aspect ratios of scene images. The trained classifiers can mine discriminative patches to accurately identify some confusing scripts. The experimental results show the good performance of our approach on four public datasets.


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