Thermomagnetic Analysis of the Lake Matano Sediments and the Surrounding Lateritic Soils, South Sulawesi, Indonesia

Thermomagnetic is one of the most commonly used measurements for determining the dominant type of magnetic mineral of samples. The measurement is separated into two distinct processes, heating and cooling. The sample susceptibility is measured for each temperature change, i.e., from room temperature to 700oC and vice-versa. Based on the thermomagnetic measurement results, magnetite is found to be the predominant magnetic minerals in Lake Matano sediments. The present study applied a correlation analysis technique on the results of thermomagnetic measurement of Lake Matano sediments and compared the result to that of lateritic soils to indicate whether a diagenetic process has occurred on the lake sediments.

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ANALISIS CAPACITY CONSTRAINED WORKER DENGAN PENDEKATAN WAKTU BAKU, DENYUT JANTUNG DAN PROFILE OF MOOD STATES (STUDI KASUS PADA INDUSTRI TEMPE “MUCHLAR”KASIHAN BANTUL)

Jurnal Agritech ◽

10.22146/agritech.9461 ◽

2014 ◽

Vol 34 (03) ◽

pp. 322

Author(s):

Maman Zuriwiatma ◽

Mirwan Ushada ◽

Guntarti Tatik Mulyati

Keyword(s):

Room Temperature ◽

Buffer Management ◽

Mood States ◽

Working Environment ◽

Profile Of Mood States ◽

Standard Time ◽

Measurement Results ◽

Capacity Constrained ◽

Potential Food ◽

Production Target

Tempe ”Muchlar” is one the potential food indutry which all the job is pursued manually. The production process is based on the worker capacity. The main problem is the industry could not fulﬁ ll the production target of half-ﬁnished Tempe product of + 3.600 kg. The research objective is to identify Capacity Constrained Worker using standard time, heart rate, proﬁ le of mood states and recommending the improvement to increase the worker capacity. The measurement results were conﬁ rmed using analysis of working environment. The research results indicated that Capacity Constrained Worker of Tempe Industry was the worker of peeling. It was indicated by the standard time of 5,63 detik/kg that could not fulﬁ ll the production target of 3.600 kg in 5 work hours. The improvement was pursued by decreasing the room temperature of working station. The improvement could increase the standard time of 5 second/kg, fulﬁ lling the production target and increasing the income. Finally the improvement using Buffer Management could improve the Capacity Constrained Worker in Tempe Industry “Muchlar”.Keywords: Standard time, Capacity Constrained Worker, production target ABSTRAKTempe ”Muchlar” merupakan salah satu industri pangan yang semua pekerjaannya dilakukan manual sehingga proses produksinya sangat tergantung kapasitas dari pekerja. Permasalahan muncul karena target produksi tempe setengah jadi sebesar + 3.600 kg tidak tercapai. Penelitian ini bertujuan untuk mengidentiﬁ kasi Capacity Constrained Worker yang terjadi menggunakan pendekatan waktu baku, denyut jantung, proﬁle of mood states serta menentukan perbaikan yang tepat untuk dapat meningkatkan kapasitasnya. Hasil pengukuran terhadap pekerja dikonﬁ rmasi dengan analisis keadaan lingkungan kerja. Dari hasil penelitian dapat ditentukan bahwa pekerja yang menjadi Capacity Constrained Worker adalah pekerja stasiun pemisahan kulit. Hal ini dibuktikan dari waktu baku yang diperoleh sebesar 5,63 detik/kg yang membuat target produksi sebesar 3.600 kg dalam 5 jam tidak tercapai. Dengan perbaikan yang dilakukan yaitu menurunkan suhu ruangan dari tinggi ke normal waktu baku pekerja dapat meningkat menjadi 5 detik/kg dan target produksi dapat tercapai serta meningkatkan pendapatan. Perbaikan dengan menerapkan buffer management dapat mengurangi stasiun kerja yang menjadi constraint. Kata kunci: Waktu baku, Capacity Constrained Worker, target produksi

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Full-scale operation of a novel two-pipe active beam system for simultaneous heating and cooling of office buildings

E3S Web of Conferences ◽

10.1051/e3sconf/201911101073 ◽

2019 ◽

Vol 111 ◽

pp. 01073

Author(s):

Alessandro Maccarini ◽

Göran Hultmark ◽

Niels C. Bergsøe ◽

Alireza Afshari

Keyword(s):

Room Temperature ◽

Energy Performance ◽

Physical Parameters ◽

Heating And Cooling ◽

System A ◽

A Value ◽

Beam System ◽

Simultaneous Heating ◽

Simultaneous Heating And Cooling ◽

Cooling Loads

This paper presents an investigation on the operation of a novel active beam system installed in an office building located in Jönköping, Sweden. The system consists of two parts: a dedicated outdoor air system (DOAS) to satisfy latent loads and ventilation requirements, and a water circuit to meet sensible heating and cooling loads. The novelty of the system is in relation to the water circuit, which is able to provide simultaneous heating and cooling through a single water loop that is near the room temperature. The energy performance of the system is currently being monitored through a number of sensors placed along the water circuit. Relevant physical parameters are being measured and data are available through a monitoring system. A preliminary analysis shows that the system is performing as designed. Results are shown for a typical week in winter, spring and summer. In particular, the supply water temperature in the circuit was between 20°C (in summer) and 23.2°C (in winter). The maximum supply/return temperature difference was found in summer and it assumed a value of 1.5 K. It is noticed that in spring supply and return water temperatures almost overlap.

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High-Temperature Modifications of Thorium Dicarbide

Advances in X-ray Analysis ◽

10.1154/s0376030800002998 ◽

1964 ◽

Vol 8 ◽

pp. 78-85 ◽

Cited By ~ 1

Author(s):

P. K. Gantzel ◽

S. Langer ◽

N. L. Baldwin ◽

F. L. Kester

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

High Temperature ◽

Thermal Effects ◽

Room Temperature ◽

Thermal Analyses ◽

Tetragonal Modification ◽

X Ray ◽

Space Groups ◽

Heating And Cooling

AbstractThermal analyses of samples of thorium dicarbide in equilibrium with graphite show arrests which indicate phase transitions at 1427 ± 21°C arid 1481 ± 28°C. These thermal effects have been observed on heating and cooling both in standard thermal analysis and in differential thermal analysis using graphite as a reference material. The microstructure of thorium dicarbide samples shows the characteristic “herringbone” pattern of a material which has undergone a martensitic-type transition.A high-temperature X-ray investigation has revealed that the observed thermal arrests correspond to erystallographic transformations. The monodinic modification found at room temperature is stable to 1427°C, at which temperature a tetragonal modification with a0 = 4.235 ± 0.002Å and c0 = 5.408 ± 0.002Å is formed. At 1481°C, the tetragonal is transformed to cubic with a0 = 5.809 ± 0.002 Å. The best agreement between observed and calculated intensities has been obtained with C-C units of 1.5-Å assumed bond length in space groups P42/mmc and Pa3 for the tetragonal and cubic modifications, respectively.

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Experimental Investigation of Mechanical Properties of PVC Polymer under Different Heating and Cooling Conditions

Journal of Engineering ◽

10.1155/2016/3791417 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 2

Author(s):

Sarkawt Rostam ◽

Alan Kareem Ali ◽

Firdaws Haidar AbdalMuhammad

Keyword(s):

Mechanical Properties ◽

Experimental Investigation ◽

Room Temperature ◽

Heating Temperature ◽

Industrial Applications ◽

Standard Samples ◽

Heating And Cooling ◽

Working Environments ◽

Cooling Conditions ◽

Temperature Ranges

Due to a widely increasing usage of polymers in various industrial applications, there should be a continuous need in doing research investigations for better understanding of their properties. These applications require the usage of the polymer in different working environments subjecting the material to various temperature ranges. In this paper, an experimental investigation of mechanical properties of polyvinyl chloride (PVC) polymer under heating and cooling conditions is presented. For this purpose standard samples are prepared and tested in laboratory using universal material testing apparatus. The samples are tested under different conditions including the room temperature environment, cooling in a refrigerator, and heating at different heating temperatures. It is observed that the strength of the tested samples decreases with the increasing of heating temperature and accordingly the material becomes softer. Meanwhile the cooling environments give a clear increasing to the strength of the material.

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Achievements and Characterizations of GaN With Ga-Polarity in Radio-Frequency Plasma-Assisted Molecular Beam Epitaxy

MRS Proceedings ◽

10.1557/proc-622-t6.22.1 ◽

2000 ◽

Vol 622 ◽

Cited By ~ 1

Author(s):

X.Q. Shen ◽

T. Ide ◽

S.H. Cho ◽

M. Shimizu ◽

S. Hara ◽

...

Keyword(s):

Room Temperature ◽

Molecular Beam ◽

Hall Effect Measurement ◽

Radio Frequency Plasma ◽

Ion Scattering ◽

Rocking Curve ◽

Initial Stage ◽

Frequency Plasma ◽

Measurement Results ◽

Scattering Spectra

ABSTRACTLattice polarities and film qualities of GaN grown by rf-MBE were investigated concentrating on the use of different buffer layer processes at the initial stage. Direct clarifying by coaxial impact collision ion scattering spectra technique, together with RHEED and chemical wet etching, were applied to identify the lattice polarity of GaN films. XRD rocking curve and photoluminescence results showed that the qualities of GaN films with Ga-polarity were dramatic improved compared to those with N-polarity. Hall effect measurement results indicated that the mobility of the Ga-face film was increased to one order higher (568 cm2/Vs in maximum at room temperature) than that of N-face one.

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The Properties of GaInAsSb/GaSb Heterostructure Grown by Mocvd and P-GaInAsSb/N-GaSb Photodiodes

MRS Proceedings ◽

10.1557/proc-415-31 ◽

1995 ◽

Vol 415 ◽

Cited By ~ 5

Author(s):

Baolin Zhang ◽

Yixin Jin ◽

Tianming Zhou ◽

Hong Jiang ◽

Yongqiang Ning ◽

...

Keyword(s):

Vapor Deposition ◽

Room Temperature ◽

Metalorganic Chemical Vapor Deposition ◽

Hole Concentration ◽

Chemical Vapor ◽

Infrared Transmission ◽

Long Wavelength ◽

Measurement Results ◽

P Type ◽

Metalorganic Chemical

ABSTRACTGaInAsSb/GaSb heterostructures have been grown by metalorganic chemical vapor deposition (MOCVD). The optical properties were characterized using low temperature(71K) photoluminescence(PL) and infrared transmission spectroscopy. The FWHM of the typical PL spectrum peaked at 2.3μm is 30meV. Hall measurement results for undoped GaInAsSb layers are presented showing a p-type background and low hole concentration of 6.5 × 1015cm−3. The room temperature performances of the p-GaInAsSb/n-GaSb photodiodes are reported. Its responsivity spectrum is peaked at 2.2 5μm and cuts off at 1.7μm in the short wavelength and at 2.4μm in the long wavelength, respectively. The room temperature detectivity D* is of 1 × 109cm.Hz1/2.W−2

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Damage Induced by Neutron Radiation on Output Characteristics of Solar Cells, Photodiodes, and Phototransistors

International Journal of Photoenergy ◽

10.1155/2013/582819 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Biljana Simić ◽

Dejan Nikolić ◽

Koviljka Stanković ◽

Ljubinko Timotijević ◽

Srboljub Stanković

Keyword(s):

Room Temperature ◽

Neutron Emission ◽

Optoelectronic Devices ◽

Neutron Radiation ◽

Solar Panels ◽

Current Voltage ◽

Measurement Results ◽

Before And After ◽

Current Voltage Characteristics ◽

Output Characteristics

This study investigates the effects of neutron radiation onI-Vcharacteristics (current dependance on voltage) of commercial optoelectronic devices (silicon photodiodes, phototransistors, and solar panels). Current-voltage characteristics of the samples were measured at room temperature before and after irradiation. The diodes were irradiated using Am-Be neutron source with neutron emission of2.7×106 n/s. The results showed a decrease in photocurrent for all samples which could be due to the existence of neutron-induced displacement defects introduced into the semiconductor lattice. The process of annealing has also been observed. A comparative analysis of measurement results has been performed in order to determine the reliability of optoelectronic devices in radiation environments.

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Experimental determination of thermal conductivity of composite materials in a wide range of values at room temperature

Engineering Journal Science and Innovation ◽

10.18698/2308-6033-2019-9-1920 ◽

2019 ◽

Cited By ~ 2

Author(s):

A.N. Chistov ◽

M.Yu. Kladov ◽

I.B. Pronin ◽

A.S. Smirnov

Keyword(s):

Thermal Conductivity ◽

Composite Materials ◽

Room Temperature ◽

Measurement Procedure ◽

Thermal Mode ◽

Wide Range ◽

Measurement Results ◽

Transfer Problems ◽

Range Of Values

In developing new composite materials and solving heat transfer problems, the thermal conductivity is an important characteristic that must be reliably determined. This often requires samples of the smallest dimensions, which is relevant for the production of pilot batches of material, as well as if they are taken directly from the product, when the amount of material is very limited. Most common methods for determining thermal conductivity require samples of relatively large sizes. To measure thermal conductivity on small-sized samples, an upgraded benchtop instrument is introduced. The instrument uses the relative method of longitudinal heat flux, which consists in a comparative measurement of a sample located between the heater and the standard in a stationary thermal mode. This paper presents the instrument design details, the requirements for the samples, explains the calibration features and the measurement procedure. The measurement results in a number of composite materials, as well as in materials with well-studied properties are analyzed. Findings show that the error of determining the thermal conductivity on a modernized instrument does not exceed several percent.

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Metastable Phenomena in the Thermally Activated Conductivity of Hydrogenated Amorphous Germanium (a-Ge:H)

MRS Proceedings ◽

10.1557/proc-297-729 ◽

1993 ◽

Vol 297 ◽

Author(s):

T. DrÜsedau ◽

D. Pang ◽

E. Sauvain ◽

P. Wickboldt ◽

E.Z. Liu ◽

...

Keyword(s):

Cooling Rate ◽

Room Temperature ◽

Equilibrium Temperature ◽

Cooling Curves ◽

Thermally Activated ◽

Heating And Cooling ◽

Higher Temperature ◽

Hydrogenated Amorphous ◽

Hydrogenated Amorphous Germanium ◽

Good Agreement

The activated conductivity of a-Ge:H between room temperature and 460K was investigated using heating and cooling rates in the range between .001 and 0.1 K/s. A splitting of the cooling curves obtained at different rates, which defines the so called equilibrium temperature TE, is observed mainly between 420 and 430K. Taking into consideration that TE depends on the maximum cooling rate, the present results are in good agreement with those reported by Eberhardt et al. The higher cooling rate always leads to the lower conductivity at any temperature below TE. These effects can be rationalized in terms of a reversible shift of the Fermi level towards midgap at higher temperature. Though reversible changes of the mobility cannot be excluded, they cannot account for our set of experimental data. Rather, changes in the density of electronic states within the mobility gap can explain the effects observed.

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Solvent and Curing Effects on Diffusion at Polyimide Interfaces

MRS Proceedings ◽

10.1557/proc-154-283 ◽

1989 ◽

Vol 154 ◽

Cited By ~ 1

Author(s):

S. F. Tead ◽

E. J. Kramer ◽

T. P. Russell ◽

W. Volksen

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Spin Coating ◽

Room Temperature ◽

Ion Beam ◽

Complete Conversion ◽

Thermally Activated ◽

Post Annealing ◽

Analysis Technique ◽

Beam Analysis

AbstractInterdiffusion at interfaces between deuterated polyamic acid (d-PAA) and polyimide (PI) films was investigated with forward recoil spectrometry, an ion beam analysis technique. The PI films were prepared by spin – coating a solution of PAA on a silicon substrate, followed by an anneal at a temperature Ti, which produced partial or complete conversion of the PAA to PI. An overlayer of d-PAA was added in one set of samples by spin – coating from solution and in another set by transferring (in the absence of solvents) a dry d- PAA film onto the PI surface. The bilayer samples were then either annealed at a temperature Td or allowed to stand at room temperature. Bilayers prepared by spin – coating d-PAA from solution directly on partially cured PI films had interdiffusion distances w that decreased with increasing values of Ti to immeasurable levels by Ti = 200 °C. The decrease in w with increasing Ti is thought to be caused by a positive Flory parameter between PAA and PI which increases with the imide fraction in the PI film; the result is an increasing immiscibility between the swollen polymer layers. No interdiffusion occurred in the solventless – transfer samples for any combination of temperatures Ti or Td from room temperature up to 400 °C. Post – annealing of spin – coated bilayers at a temperature Td up to 400 °C was ineffective in producing any additional interdiffusion. Both of these results indicate that thermally activated interdiffusion (even for initially unimidized samples) does not exist in the absence of solvents, an effect attributed to the rapid increase of the glass transition temperature of the polymer with imidization.

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