scholarly journals SINKHOLE DEVELOPMENT MODEL. PART 2. INVESTIGATION OF THE STRUCTURE OF SINKHOLES IN NATURE

2019 ◽  
Vol 14 (1) ◽  
pp. 44-58
Author(s):  
O. B. NESHCHETKIN ◽  
M. O. NESHCHETKIN
Keyword(s):  
Main Stage ◽  
Cylindrical Shape ◽  
Cone Penetration ◽  
Almost Everywhere ◽  
Initial Stage ◽  
Drilling Operations ◽  
Natural Equilibrium ◽  
Three Stages ◽  
Lower Depth ◽  
Good Agreement

The main methods of sinkhole research in nature were: the morphometric method, excavations of sinkholes, cone penetration test (CPT) and drilling in the sinkhole zones, the study of the kinematic and dynamic characteristics of the sinkholes and accompanying effects. The study of morphological features of the sinkhole parameters has allowed to establish, that almost everywhere the appearance of the sinkholes corresponds to the elementary geometric shapes: arched — cylindrical — conical — cupped — saucer-shaped. In the case where the covering deposits are represented by clayey soils, most of the karst sinkholes have an arched or cylindrical shape and conical and cupped forms are typical for sandy soils. Excavations of karst sinkholes have established the arch character of the collapse of soils in the intermediate cavity in the development of a sinkhole on the earth's surface. The CPT of the sinkhole zones revealed specific features of the soil decompaction in the sinkhole, which testify to the collapse of the soils into the intermediate cavity. Drilling operations in the conditions of carbonate and sulphate karst have established that the intermediate cavities develop over the karst cavities. In 2015, the authors were lucky to observe the sequence of the sinkhole development on the earth's surface and to distinguish three stages of the sinkhole formation. The results of karst sinkholes investigations in nature conditions and laboratory modeling of the mechanism of their formation are in good agreement and clearly indicate that the destruction of the cover soils over the karst cavities in the collapse of their roofs begins with the formation of a primary intermediate cavity the surface of which is described by an arch of natural equilibrium. Further, there is a successive collapse of the arch of this primary intermediate cavity and the formation of an intermediate cavity at a lower depth. Thus, the intermediate cavity "moves" to the earth's surface. In the initial stage of formation of a sinkhole on the earth's surface, concentric cracks appear and a small saucer-shaped lowering, the formation of an arch sinkhole occurs in the main stage, in the final stage there is a collapse and displacement of blocks of soil with formation of a depression of a steady state.

scholarly journals Igdlukúnguaq nickeliferous pyrrhotite. Texture and composition. A contribution to the genesis of the ore type

1958 ◽  
Vol 17 ◽  
pp. 1-167
Author(s):  
H Pauly
Keyword(s):  
Mineral Content ◽  
Historical Data ◽  
Main Stage ◽  
Chemical Analyses ◽  
Microscopic Description ◽  
Native Iron ◽  
Initial Stage ◽  
Third Stage ◽  
Chain Of Evidence ◽  
Three Stages

Because of the very remarkable phases and structures it contains, the only nickeliferous pyrrhotite so far known in Greenland is given a very thorough ore-microscopic description. The locality where this block of ore – about 28 tons – was found by Steenstrup in 1872 is situated on the Northeast coast of the island of Disko, which in turn lies off the West coast of Greenland. The ore was contained within a dike rock belonging to the basalt complex which i. a. forms the main part of Disko and the neighbouring regions of the Greenlandic coast. The ore itself, although it has the composition of normal nickeliferous pyrrhotite rich in nickel, presents a remarkable variety of phases and exsolution structures. It is the author's belief that these components form an almost unbroken chain of evidence covering the whole range, from the first consolidated sulphides to exsolution phenomena representing temperatures of under 200° C. The following exsolutions were found in the ore: 1. Chalcopentlandite, i. e. a pentlandite containing about 10 per cent. of chalcopyrite. Formed at near 850°C. 2. Chalcopyrite in rectilinear lamellae following (hoho), formed at around 700° C. 2a. Chalcopyrite in rectilinear lamellae along (hohl), formed at around 700° C. 2b. Chalcopyrite in rectilinear lamellae following (hohl1), likewise formed at near 700°. 3. Chalcopyrite in flame-like lamellae corresponding to about 550°C. 3a. Chalcopyrite in flame-like lamellae of another type. 4. Pentlandite sparks formed at near 550°C. 5. Pentlandite flames of the well-known type formed at 310 °C. 6. Pyrrhotite α-β lamellae formed at around 140° C. The study of the compact ore showed that development of the ore comprised three stages: An initial stage, from which the primary oxides came as a result of gases originally held within the molten sulphide mass. The main stage, where consolidation of the sulphides took place together with the solidification of oxidic material. The third stage was dominated by processes of hydrothermal character. The formation of both sulphidic and oxidic phases took place widely at the expense of earlier-formed compounds. The wealth of new observations which the author was able to make during his work on the Greenlandic ore is described in detail, after brief mention of historical data, in pages 27-65. Chemical analyses of rocks and ore will be found on pages 21 and 25. On page 65 is a list showing the mineral content of the ore. The following pages, 66 to 101, contain a discussion of the microscopic observations; the second half of that discussion deals especially with the significance of the gases originally held within the sulphide mass. Water and carbon dioxide seem to have played an important role in the forming of the ore, not as carriers of the ore material but as participants in the chemical reactions. Comparison of Canadian, African, Scandinavian and Australian occurrences with several new observations made by the author is followed by a chapter devoted mainly to summing up and placing the nickeliferous pyrrhotite in relation to other geological phenomena. The last pages contain a brief discussion of a possible relation between nickeliferous pyrrhotite and the well-known occurrence of native iron in the Greenlandic plateau basalts.

Thermal Analysis of Stacked Ni-MH Battery

1999 ◽  
Author(s):  
Katsumi Hisano ◽  
Hideo Iwasaki ◽  
Masaru Ishizuka ◽  
Tetsuya Yamane
Keyword(s):  
Thermal Analysis ◽  
Numerical Analysis ◽  
Temperature Rise ◽  
Test Case ◽  
Charge Retention ◽  
Calculated Temperature ◽  
Computational Load ◽  
Three Stages ◽  
Mh Battery ◽  
Good Agreement

Abstract Numerical analysis was carried out to evaluate the temperature rise and charge retention of Ni-MH batteries as pallet loads. In this paper, thermal analysis of pallet loads which contain 2400 mAh Ni-MH batteries is considered as a test case. To reduce computational load, thermal analysis was performed in three stages. Measured and calculated temperature rise of the load showed good agreement, and it can be observed that there exists an appropriate charge retention of the battery to sustain high retention during transportation.

A model for the vibrator–ground coupling vibration and the dynamic responses under excitation of sweep signal

2019 ◽  
Vol 22 (8) ◽  
pp. 1855-1866 ◽  
Author(s):  
Gang Li ◽  
Zhi-Qiang Huang ◽  
Zhang-Hua Lian ◽  
Lei Hao
Keyword(s):  
Dynamic Stiffness ◽  
Low Frequency ◽  
Dynamic Responses ◽  
Coupling Vibration ◽  
Lower Velocity ◽  
Dynamic Damping ◽  
Velocity Response ◽  
Cell Test ◽  
Three Stages ◽  
Good Agreement

To analyze the behavior of the vibrator–ground coupling vibration, a model containing equivalent dynamic stiffness and equivalent dynamic damping to describe the interaction between the vibrator and the ground is established based on half-space theory. According to load cell test, this model shows a good agreement with the experimental data. Dynamic responses of the structure are analyzed on displacement, velocity, acceleration, and ground force. Results show that the stroke and pump displacement are main constraints that limit the bandwidth of vibrator toward low frequency, and the stroke of conventional vibrator is not long enough to achieve lower frequency. Analysis of velocity response indicates that with the increase of frequency, a larger mass results in a lower velocity under external force. The influence of the ground acting on the baseplate is limited, and the acceleration of the baseplate is determined by its own mass beyond 80 Hz. Analysis of ground force shows that the response of the structure can be divided into three stages. The reaction mass, the baseplate, and the ground play different roles in dominating the ground force at different frequency bands.

scholarly journals Pulse Duration and Wavelength Effects of Laser Ablation on the Oxidation, Hydrolysis, and Aging of Aluminum Nanoparticles in Water

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 767 ◽  
Author(s):  
Ke Zhang ◽  
Dmitry S. Ivanov ◽  
Rashid A. Ganeev ◽  
Ganjaboy S. Boltaev ◽  
Pandiyalackal S. Krishnendu ◽  
...  
Keyword(s):  
Pulse Duration ◽  
Morphological Transformation ◽  
Short Pulses ◽  
Al Nanoparticles ◽  
Initial Stage ◽  
Three Stages ◽  
Points Of View ◽  
Hydrolysis Of ◽  
Stable Stage

We analyzed the formation of the aluminum (Al) nanoparticles (NPs) with triangular shape obtained by ablating Al bulk in liquid using pulses with different durations (5 ns, 200 ps, and 30 fs) and wavelengths (355 nm, 800 nm, and 1064 nm). We report three stages of synthesis and aging of Al NPs: Formation, transformation, and stable stage. The NPs prepared by different pulses are almost identical at the initial stage. The effects of duration and wavelength of the ablation pulses on the aging of NPs are revealed. Pulse duration is determined to be essential for morphological transformation of NPs, while pulse wavelength strongly influences particle sizes. NPs produced by ultra-short pulses have smaller sizes and narrow size distribution. We demonstrate that oxidation and hydrolysis of Al in water are the results of ablation for all pulse durations and wavelengths, which also strongly modify the preferable reaction path of NPs in water, thus affecting the composition and morphology of triangle NPs. The results of modeling of the NPs generation in water due to a 50 ps laser pulse interacting with a thick Al target are presented. Water-based effects in the formation of NPs, their evolution, and solidification are considered from the mechanical and thermophysical points of view. The detailed analysis of the modeling results allowed for determination of the main mechanism responsible for the ablation process followed by the NPs formation.

Evolution of node impact based on secondary propagation

2019 ◽  
Vol 34 (02) ◽  
pp. 2050027
Author(s):  
Fuzhong Nian ◽  
Kai Gao
Keyword(s):  
Real Life ◽  
Propagation Model ◽  
Information Propagation ◽  
Actual Situation ◽  
Scale Free Network ◽  
Scale Free ◽  
Initial Stage ◽  
Free Network ◽  
Three Stages ◽  
Stable Stage

In real life, the propagation ability of the information disseminator is one of the important factors which is determined to propagate information. The influence of the node, which is altered with time, is proposed to reflect the propagation ability of the information disseminator for the significance of the information propagation in the actual situation in this paper. Therefore, the influence of the node is divided into the high-impact node and the low-impact node. Furthermore, the SSIR information propagation model is proposed and the dynamic BA scale-free network is constructed to carry out evolution of node impact based on secondary propagation experiments. The experiment results indicate three stages, including the initial stage, the rapidly rising stage and the stable stage. The propagation details of the different messages are distinct. However, the trend of propagation is similar.

scholarly journals Drying kinetics of bananas by natural convection: Influence of temperature, shape, blanching and cultivar

2011 ◽  
Vol 35 (2) ◽  
pp. 368-376 ◽  
Author(s):  
Soraia Vilela Borges ◽  
Maurício C. Mancini ◽  
Jefferson Luiz Gomes Corrêa ◽  
Julia Benedito Leite
Keyword(s):  
Natural Convection ◽  
Exponential Model ◽  
Positive Influence ◽  
Drying Rate ◽  
Cylindrical Shape ◽  
Sample Shape ◽  
Drying Behavior ◽  
Drying Rates ◽  
Kinetics Of ◽  
Good Agreement

The influence of variables as temperature, solid shape, temperature, branching and cultivar on drying of bananas were studied. Bananas from cv. Prata and D'água, on disk and cylindrical shape, blanched or not, were dehydrated in a tray dryer in natural convection at 40 and 70ºC. Drying behavior was analyzed by using a mathematical model. The exponential model showed good agreement to experimental data (r² 0.93 - 0.99 and standard error: 0.01- 0.05). Temperature presented positive influence on drying rate in all the tested conditions. With respect to the sample shape, the disk shape carried out to significantly higher drying rates only for D'água cultivar without blanching. Blanching was significantly influent, with positive influence, on drying rate of banana cv. Prata at 40º C. The influence of the cultivar did not present a defined tendency.

Coaching Program in Detention Centers as Process of Preparing Inmate Life Skills

2020 ◽  
Vol 1 (4) ◽  
pp. 91-98
Author(s):  
Peri Aldaus ◽  
Alim Harun Pamungkas
Keyword(s):  
Development Stage ◽  
Initial Time ◽  
Literature Study ◽  
Second Development ◽  
Former Prisoners ◽  
Detention Centers ◽  
Stage Of Development ◽  
Initial Stage ◽  
Effective System ◽  
Three Stages

This paper is motivated by the challenges that will be faced by former prisoners when returning to society. The purpose of this paper to describe to the coaching program aimed at prisoners who are in detention centers. This paper used a literature study method by collecting data related to the topic of articles obtained from various sources. Search for published articles using the selected keywords. Articles or journals that match the inclusion and exclusion criteria are taken for further analysis. The concludes of this paper that coaching is divided into stages, namely the initial stage, which is calculated from the initial time of entry up to one-third of the criminal period. Meanwhile, the first stage of development is a third to half of the sentence. Next is the second development stage, namely half to the end of the criminal period. These three stages constitute an effective system.

Numerical Analysis of Automobile Environment During the Cooling Period in Summer

2008 ◽  
Author(s):  
Kum-Bae Lee ◽  
Md. Faisal Kader ◽  
Young-Muk Youn
Keyword(s):  
Three Dimensional ◽  
Considerable Change ◽  
Practical Significance ◽  
Instrument Panel ◽  
Shelf Area ◽  
Cooling Period ◽  
Initial Stage ◽  
Temperature And Humidity ◽  
Humidity Profiles ◽  
Good Agreement

Understanding the temperature and humidity profiles inside a vehicle when the A/C is on during summer is of paramount practical significance to maintain comfortable environment. In this paper, the airflow patterns, temperature and humidity distributions are predicted utilizing a three-dimensional finite volume numerical method and measured experimentally inside the automobile. Numerical analyses of the three-dimensional geometry predict a detailed description of fluid flow patterns. The velocity vectors from the side instrument panel registers impinge on the front occupant’s chest to head then travel forward and finally reach to the rear parcel shelf area. The undesirable returning flow passing by the driver’s head and neck has been observed. The velocity vectors from the central instrument panel registers travel directly to the rear compartment. A recirculation has been observed near the occupant’s knee area of the front compartment and rear compartment. The Temperature comes down to a comfortable range almost linearly at the initial stage. After that no considerable change has been observed. A good agreement has been found between the numerical and experimental results.

scholarly journals Peningkatan Kompetensi Supervisi Kepala Sekolah Melalui Supervisi Kelompok Di Sekolah Dasar

2016 ◽  
Vol 11 (1) ◽  
pp. 8
Author(s):  
Suryantini Suryantini
Keyword(s):  
Data Analysis ◽  
Action Research ◽  
Score Improvement ◽  
Initial Stage ◽  
Analysis Technique ◽  
Collecting Techniques ◽  
Three Stages ◽  
Back Stage ◽  
Academic Year ◽  
Group Technique

The research is aimed to: 1) describe the process of managerial supervision using group technique to improve the principals’ supervisory competence; and 2) imrove the principals’ supervisory competence at Gugus II Bima UPTD Dikpora Kecamatan Serengan of Surakarta academic year 2012/2013 through managerial supervision using group technique.The type of the research is an action research. The research was done at Gugus II Bima UPTD Dikpora Kecamatan Serengan of Surakarta. The subjects of the research were 6 principals at Gugus II Bima UPTD Dikpora Kecamatan Serengan of Surakarta. The data collecting techniques were done using observation,  interview  and  document  techniques.  The  data  analysis  technique was done using Kemmis and Taggart model.The research concludes that: 1) the managerial supervision processes were done in three stages, namely: initial stage, observation stage, and feed-back stage; and 2) the managerial supervision using group technique is effective in improving the principals’ supervisory competence at Gugus II Bima UPTD Dikpora Kecamatan Serengan of Surakarta academic year2012/2013. It is demonstrated by the score improvement in each cycles.

scholarly journals Pengetahuan Pengunjung Tentang Instruksi Pasca Pencabutan Gigi Di Pusat Pengobatan Mata Dan Gigi

2021 ◽  
Vol 3 (1) ◽  
pp. 41-49
Author(s):  
Reny Augtri Soviana ◽  
Dian Femala ◽  
Jojok Heru Susatyo ◽  
Budi Suryana
Keyword(s):  
Tooth Extraction ◽  
Dental Treatment ◽  
Sampling Technique ◽  
Treatment Center ◽  
Purposive Sampling ◽  
Initial Stage ◽  
Healing Of Wounds ◽  
Three Stages ◽  
Descriptive Method ◽  
Implementation Stage

Visitors who had their teeth extracted at the Eye and Dental Treatment Center (PPMG) Pontianak City did not follow the instructions given by the operator after having their teeth extracted. From the results of a field survey conducted, about 35% - 50% of patients who extracted teeth did not follow more than 1 post-extraction instruction. The result of ignoring this can have an impact on the healing of wounds from tooth extraction. The purpose of this study was to determine the knowledge of visitors about post-tooth extraction instructions at the Center for Eye and Dental Medicine (PPMG) Pontianak City 2015. This study used a descriptive method which was conducted on 57 respondents who were taken using purposive sampling technique for 2 weeks, data collection techniques through three stages, namely the initial stage, the implementation stage, and the final stage then processed using SPSS version 18.0 and presented in tabular form. The results showed that most of the respondents had good knowledge of the category, namely 30 people (52.6%), while respondents who had sufficient knowledge were 14 people (24.6%) and respondents who had less knowledge were 13 people (22, 8%). Knowledge of post-tooth extraction instructions is important in order to provide understanding to the patient to prevent complications after tooth extraction. Pengunjung yang melakukan pencabutan gigi di Pusat Pengobatan Mata dan Gigi (PPMG) Kota Pontianak tidak mengikuti instruksi yang diberikan oleh operator setelah melakukan pencabutan gigi. Dari hasil survey lapangan yang dilakukan, sekitar 35% - 50% pasien yang mencabut gigi tidak mengikuti lebih dari 1 instruksi pasca pencabutan gigi. Akibat dari mengabaikan hal tersebut dapat berdampak pada penyembuhan luka bekas pencabutan gigi. Tujuan penelitian ini adalah untuk mengetahui pengetahuan pengunjung tentang instruksi pasca pencabutan gigi di Pusat Pengobatan Mata dan Gigi (PPMG) Kota Pontianak Tahun 2015. Penelitian ini menggunakan metode deskriptif yang dilakukan terhadap 57 responden yang diambil menggunakan teknik purposive sampling selama 2 minggu, teknik pengumpulan data melalui tiga tahap yaitu tahap awal, tahap pelaksanaan dan tahap akhir kemudian diolah menggunakan SPSS versi 18.0 serta disajikan dalam bentuk tabel. Hasil penelitian terlihat bahwa sebagian besar responden memiliki pengetahuan kategori baik yaitu 30 orang (52,6%), sedangkan responden yang memiliki pengetahuan kategori cukup yaitu 14 orang (24,6%) dan responden yang memiliki pengetahuan kategori kurang yaitu 13 orang (22,8%). Pengetahuan tentang instruksi pasca pencabutan gigi penting dilakukan agar memberikan pemahaman kepada pasien untuk mencegah terjadinya komplikasi pasca pencabutan gigi.

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