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Acceleration sensors for structural health monitoring of engineering structures under the influence of environmental factors at low frequencies Structural health monitoring (SHM) is increasingly used to continuously assess the condition of engineering structures. Important assessment parameters are global system properties, such as eigenfrequency, which are measured by accelerometers. micro‐electro‐mechanical systems (MEMS) sensors are often used, but have a high noise level. Alternatively, low‐noise IEPE (integrated electronics piezo electric) sensors can be used, which reliably detect vibrations even with the slightest structural excitation. Another problem is that changes in eigenfrequency due to structural damage are difficult to distinguish from changes in eigenfrequency due to environmental effects. The latter change the properties of both the structure and the measurement system. In order to investigate environmental effects on the measurement system in the field of civil engineering, IEPE accelerometers have been analyzed for their transmission behavior in the low‐frequency acceleration range. It was found that the behavior is not only frequency dependent, but also temperature dependent, while humidity has no influence. These nonstructural effects must be compensated for to ensure robust condition monitoring. IEPE sensors are recommended for civil engineering applications because of their high signal‐to‐noise ratio and ability to reliably detect low‐frequency structural vibrations. [ABSTRACT FROM AUTHOR]

Copyright of Teras Jurnal: Jurnal Teknik Sipil is the property of Teras Jurnal: Jurnal Teknik Sipil and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Politische Vierteljahresschrift is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tribologie und Schmierungstechnik is the property of Narr Francke Attempto Verlag GmbH & Co.KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The distribution of non-volcanic geothermal energy is widely found on the island of Sulawesi, one of which is in Lompio Village, Sirenja District, Donggala Regency, Central Sulawesi Province. It is important to study the geothermal potential in the village in order to learn how the geothermal system works. This study aims to identify the distribution pattern of temperature distribution in shallow soil depths as a manifestation of the geothermal system below the surface and its relation to geothermal manifestations that appear on the surface. This research was carried out through a series of field observations and direct soil temperature measurements in the study area using a thermometer. The results show that the distribution pattern of land temperature distribution in the high-temperature zone is associated with the presence of geothermal manifestation points on the surface (hot springs). The association of temperature and manifestation is possible because the presence of hot springs is an indication of a weak zone for the release of hydrothermal fluid from the geothermal system, which is correlated with the geological structure in the research area.

The density of β-cyanopropionaldehyde, in a wide range of temperature and pressure was determined. Also, the heat capacity of that aldehyde at constant pressure and different temperatures was experimentally measured. The research has been cleared by different formulas. [ABSTRACT FROM AUTHOR]

Copyright of Grundwasser is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anaesthesiologie & Intensivmedizin is the property of DGAI e.V. - Deutsche Gesellschaft fur Anasthesiologie und Intensivmedizin e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The impact of climate change on insect pests is an emerging topic in forestry and forest science. This study investigates the relationships between two broadleaved forest pests – spongy moth (Lymantria dispar L.) and brown-tail moth (Euproctis chrysorrhoea L.) – and oaks (Quercus sp.) as their hosts. Oak forests cover almost one-third of the total forest area of Serbia and are ecologicallyvery valuable, but at the same time vulnerable, as being affected in adverse ways by several primary pests and pathogens. Since 1862, Serbia experienced several extremely large outbreaks of spongy moth with more than a hundred thousand hectares completely defoliated each time, while brown-tail moth occurred periodically with a much lower spatial extent. The aim of this research was to investigate the effect of UV radiation (UVR) and air temperature on spongy moth and brown-tail moth in Serbian forests. We used simulations of the coupled regional climate model EBU-POM (Eta Belgrade University-Princeton Ocean Model) for the A1B scenario for the period 2001-2030 as main input and different statistical methods to explore relationships between observations of pest spread and climate change impacts. Our results suggest (i) increasing the areas affected by spongy moth due to its sensitivity on UVR in May, and (ii) altitudinal spreading of brown-tail moth population up to 800 – 1000 m. This research indicates that in situ forest observations in Serbia are not only affected by climate change, but also by the combined effect of climate on forest pests. For further research, we recommend exploring other forest stressors or dieback phenomena in European forests by applying the same or similar regional climate model dataset. [ABSTRACT FROM AUTHOR]

In its development, concrete technology has innovated a lot in the use of its materials, such as the utilization of unused material waste. Jejawi is a village area located in OKI Regency and one of the livelihoods of its residents is gardening with the produce of Geda bananas, where after harvesting the banana stems are no longer used and become waste. This study aims to determine the effect of the utilization of Geda banana midrib ash in Jejawi Village as an added material on the quality of concrete. With experimental methods carried out in the laboratory, mixing the concrete material using the SNI quality standard K.225 and then adding variations of Geda Desa Jejawi banana ash which has been burned with an average temperature of 316oC by 2%, 2.5%, and 5%. From the test results, the compressive strength of normal concrete is 225.54 kg/cm2, the compressive strength of the banana ash variation of 2% concrete is 234.76 kg/cm2, the compressive strength of the banana ash variation of 2.5% concrete is 217.19 kg/cm2, and the compressive strength of the 5% banana ash variation of concrete is 203.64 kg/cm2. From the test results, there was an increase in compressive strength in the variation of the addition of 2% banana ash from normal concrete, but it decreased in the 2.5% banana ash variation and decreased again at 5%. So it was concluded that the addition of Geda banana stem ash in Jejawi Village could be used as an additional material for the K 225 concrete mixture at the addition of 2% banana ash

Studies on the use of animal waste as charcoal ingredient in the needs of activated charcoal material has been carried out and developed. Activated charcoal is produced through activation process at a certain temperature, condition, and time in order to creat a higher carbon content in charcoal . One of the important factors in the manufacture of activated charcoal is the temperature during the production process. The purpose of this study is to discuss the influence of temperature factor of mussel shells and beef bones on water content, ash content, volatile matter and fixed carbon during the charcoal production process. The research is carried out through experimental method of making chorcoal with temperature variations of 400, 500, 600, 700, and 800 oC. The result of the experiment shows the highest ash content and water content found respectively in beef bone charcoal of 800 oC which is 98,697 %, and of 400 oC which is 4,942 %, while the highest volatile matter and fixed carbon levels are found in clam shell charcoal of 800 oC which is 6,717 %, and of 500 oC which is 43,282 %. The result concluded that the effect of the temperature of the production process affects the water content, ash, volatile matter and fixed carbon.

Experimental and numerical investigations of constraining forces due to temperature differences A realistic estimation of the constraint force is of great importance for a safe and economical design of reinforced concrete members subjected to constraint. Previous work suggests that a distinction should be made as to whether concrete shrinkage or a temperature difference is the cause of the constraint forces. In the present paper, experiments are described in which reinforced concrete components held on both sides were experimentally examined under uniform temperature differences of up to 70 K. The resulting cracking and the corresponding forces are elaborated, compared with results from numerical simulations, and extended by the variation of the degree of longitudinal reinforcement, concrete tensile strength and degree of restraint. The significant differences in the load‐bearing behavior compared to members subjected to constraint forces resulting from shrinkage are confirmed. In addition, it is shown that the final state of full cracking of the respective structural member can be achieved at strains much lower than 0.8 ‰. The usual procedure for a combined loading and restraint, in which the design for both types of loading is carried out separately and then the larger of the two determined reinforcement cross sections is provided, can in part be clearly on the unsafe side. [ABSTRACT FROM AUTHOR]

Introduction: Body temperature measurement is a fundamental requirement for clinical decisions in nursing care, medical diagnosis, and treatment. Therefore, it is pivotal that body temperature measurements are accurate and precise., Aims: To test the diagnostic accuracy of an ear temperature screening procedure among adult hospitalized patients. Further aims were to test the precision of the measurements being carried out by trained registered nurses compared with daily routine practice and to investigate patients' preferences for different measurement methods., Methods: In Aalborg University Hospital, 274 patients were included in a cross-sectional comparative study. Each patient had four temperature measurements and responded to a survey regarding their preference for measurement. Bland-Altman analysis was used to evaluate the difference between ear- and rectal measurements. Sensitivity and specificity were evaluated at different cut-off points., Results: The ear temperature was 0.1 to 0.2 °C lower than rectal temperature. At a cut-off point at 37.5 °C an ear thermometer is accurate and can be used for screening, while higher cut-off points risk missing patients with fever. There was no significant difference in the mean temperature measured by a trained registered nurse or other staff members and patients. Patients preferred ear measurements to rectal measurements., Conclusion: The tested ear thermometer is accurate for screening fever in an adult population during hospital admission. Using ear measurement as a screening tool can contribute to a less resource-demanding care activity and a more convenient alternative to rectal measurements in hospitalised patients., (Copyright © 2024. Published by Elsevier GmbH.)

The effect of initial heat‐treated conditions on change of mechanical properties and microstructure evolution was investigated by caliber rolling of medium carbon alloy steel (ASTM 5140). Initial samples with two different kinds of microstructures of pearlite‐ferrite and martensite were prepared, and then caliber rolling was conducted at 550 °C, 600 °C, 650 °C, respectively. It was found that the caliber rolling provides better strength‐ductility balance and impact properties, when the rolling temperature is at 550 °C, the ultimate tensile strength of quenched steel can reach 1.3 GPa, and low‐temperature impact energy of 140 J at −80 °C. In a word, the improvement of mechanical properties is attributed to the ultrafine elongated grain structures, dispersed nano‐size carbides, and formation of distinct chromium segregation bands, furthermore, delamination crack is an effective measure to improve impact energy. [ABSTRACT FROM AUTHOR]

Alginat merupakan polimer polisakarida linier yang sangat mudah larut dalam air dengan densitas dan viskositas yang dapat diatur sesuai keperluan. Sifat khas ini membuat alginat banyak digunakan dalam industri pangan maupun non pangan. Seperti pada kebanyakan bahan alam lainnya, densitas larutan alginat pada umumnya juga dipengaruhi oleh temperatur, konsentrasi dan waktu pengadukan. Karenanya, penelitian ini bertujuan untuk meningkatkan kepresisian densitas larutan alginat dengan pengaturan temperatur (30, 45, 60 dan 75°C), konsentrasi alginat (1, 2, 3, 4 dan 5% massa) dan waktu pengadukan (15, 30, 45 dan 60 menit) menggunakan metode piknometri. Hasil penelitian menunjukkan bahwa semakin tinggi temperatur maka densitas akan semakin rendah, sebaliknya semakin tinggi konsentrasi dan waktu pengadukan maka densitas larutan alginat akan semakin meningkat. Dengan demikian, dapat disimpulkan apabila menginginkan densitas larutan alginat 0,9228 g/ml maka konsentrasi alginat yang digunakan 2% dengan suhu 30°C dan waktu pengadukan 30 menit.

The textile materials can be used in many technical applications in various fields, such as automotive. Depending on the application areas, the textile or fiber‐based materials have to meet certain predetermined requirements. Textile yarns can be used as reinforcing cords in composites in which an elastomeric matrix is used. The basic mechanical tensile test at standard temperature does not provide all the information required for obtaining the material parameters. The tests are also necessary to be performed at reduced temperatures, depending on the following application. Furthermore, it is necessary to consider stress relaxation in specific tests for the practical use. In this work, there is the experimental investigation of the effect of the selected temperatures (20 °C and 120 °C) and the relaxation times (60 s and 120 s) on the mechanical properties of the selected textile yarns from polyamide 6.6 under the uniaxial tensile tests. The results reveal that the relaxation time for the first 20 seconds is interesting because there is a significant decrease in the force while holding the strain. A final method is proposed, and it can be used for any other applications, and it guarantees the repeatability of measurements in the relatively fast measured time. [ABSTRACT FROM AUTHOR]

Monitoring of the Theodor‐Heuss‐bridge in Düsseldorf – part 1: motivation, monitoring concept and structural behavior findings The Theodor‐Heuss‐bridge in Düsseldorf is Germany's oldest cable‐stayed bridge and the world's first bridge with harp‐shaped cables. Since its opening in 1957, the traffic load has increased progressively. As with many other bridges with orthotropic deck slabs, this led to deterioration over time – for instance in the form of cracks. A recalculation of the structure shows significant deficits – especially with regard to fatigue in the orthotropic deck. Therefore, a monitoring system consisting of more than 80 sensors was installed on the structure in 2019 and operated for more than one year. This paper shows the development of the monitoring concept, its implementation and evaluation. Findings on the load‐bearing behavior are derived from the measurement data. A significant correlation between the fatigue loads and the temperature is found. On the one hand, the stiff asphalt layer contributes to the load transfer, on the other hand, it has a greater load distribution effect. The monitoring also shows that the influence of wheel loads dominates and that a reduction in the permissible gross vehicle weight has only a small benefit. Rather, the wheel loads must be limited in order to relieve the components of the orthotropic deck. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity describes the ability of an organism with a given genotype to respond to changing environmental conditions through the adaptation of the phenotype. Phenotypic plasticity is a widespread means of adaptation, allowing organisms to optimize fitness levels in changing environments. A core prerequisite for adaptive predictive plasticity is the existence of reliable cues, i.e. accurate environmental information about future selection on the expressed plastic phenotype. Furthermore, organisms need the capacity to detect and interpret such cues, relying on specific sensory signalling and neuronal cascades. Subsequent neurohormonal changes lead to the transformation of phenotype A into phenotype B. Each of these activities is critical for survival. Consequently, anything that could impair an animal's ability to perceive important chemical information could have significant ecological ramifications. Climate change and other human stressors can act on individual or all of the components of this signalling cascade. In consequence, organisms could lose their adaptive potential, or in the worst case, even become maladapted. Therefore, it is key to understand the sensory systems, the neurobiology and the physiological adaptations that mediate organisms' interactions with their environment. It is, thus, pivotal to predict the ecosystem-wide effects of global human forcing. This review summarizes current insights on how climate change affects phenotypic plasticity, focussing on how associated stressors change the signalling agents, the sensory systems, receptor responses and neuronal signalling cascades, thereby, impairing phenotypic adaptations. [ABSTRACT FROM AUTHOR]

Proposal for a change in the temperature load model for concrete and composite bridges – Results of the research project MTE 2.0 "Modified temperature load model for railway bridges" As part of the research project MTE 2.0 initiated by ÖBB‐Infrastruktur AG, extensive investigations into the actual temperature loads on railway bridges were carried out. As part of the project, measurements on bridge structures as well as evaluations of statistical meteorological climate data over a period of 50 years, probabilistic evaluations and both analytical and numerical calculations were carried out. Based on the results of the project, the design model for temperature loads according to Eurocode 1 was adapted for railway bridges (concrete or composite structures) and a proposal for an optimized temperature load model was newly developed, which is summarized in the following article. Comparative calculations for railway bridges have shown that the elongation of the bridges in the ultimate limit state according to the optimized load model are 25 % to 45 % lower than those based on ÖNORM EN 1991‐1‐5 or ÖNORM B 1991‐1‐5, respectively. Taking into account the partial safety factors and the characteristic values, the actual elongations of existing bridges can be described much more realistically using the newly developed load model. [ABSTRACT FROM AUTHOR]

The nature of the physicochemical interaction in the Tm-As-S and Tm-As-Se systems was studied along various cross sections by methods of Differential Thermal (DTA), X-Ray Diffraction (XRD) and Microstructural (MSA) Analyzes, measuring their micro-hardness and determining their electrophysical properties. The investigation of the alloys of the system started by studying the properties of the initial components in cooling modes of 7–10deg/min. After establishing the boundary of the glass formation region in the systems, the physicochemical properties of glasses and intermediate phases were studied. Analysis showed that all effects on the thermograms were reversible. The compounds of TmAsS3, TmAs4S7, TmAs2S4, Tm3As4S9 compositions were formed in the As2S3-Tm2S3, As2S3-TmS systems. The compounds of TmAs4S7, TmAsS and TmAs2S4 compositions melted congruently, while the compounds of Tm3As4S9 and TmAsS3 melted incongruently. TmAsSe, TmAsSe3, TmAs4Se7, TmAs2Se4 and Tm3As4Se9 phases were formed in the Tm-As-Se system while Tm3As4Se9 was formed by the peritectic reaction TmSe + L ↔ Tm3As4Se9. Microstructural analysis showed that all alloys of the Tm-As-S, Tm-As-Se cross sections were two-phase, except for the composition of intermediate phases. Proceeding from the results of XRD, the lattice parameters of TmAsS, TmAsS3, TmAs4S7, TmAs2S4, as well as parameters of selenium-containing compound were calculated; it found that it crystallized in the rhombic syngony. Based on the results of physicochemical analysis, it was established that the studied cross sections were quasi-binary sections of the Tm-As-S and Tm-As-Se ternary systems. The phase diagram of cross sections with the participation of sulfur and selenium was plotted using the results of physicochemical analysis; it established that the studied cross sections were quasi-binary sections of the Tm-As-S and Tm-As-Se ternary systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Food Quality / Archiv für Lebensmittelhygiene is the property of Presse Dienstleistungsges. mbH & Co. KG and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Persaingan ketat antar pelaku industri pengecoran logam menuntut penggunaan teknologi pengecoran untuk menghasilkan produk berkualitas tinggi dan kuantitas yang banyak dengan biaya produksi yang optimal. Beberapa parameter yang memengaruhi produk hasil pengecoran adalah temperatur saat penuangan serta laju penuangan. Temperatur tuang harus memperhitungkan kehilangan panas yang disebabkan oleh pemindahan logam melalui ladle, karena antara tungku dan cetakan ada jarak tertentu dan pengaruh lingkungan sekitar yang menyerap panas. Oleh karena itu, diperlukan sistem monitoring yang dapat memonitor laju penurunan temperatur saat penuangan secara real time serta terekam, sehingga dapat menjadi bahan analisis untuk memperoleh hasil pengecoran yang optimal. Serta diperlukan juga suatu sistem monitoring penggunaan energi saat proses pengecoran berlangsung, agar harga pokok produksi hasil coran dapat dikendalikan. Teknologi revolusi industri 4.0 pada industri pengecoran logam, khususnya baja karbon dan besi tuang/cor, dapat membantu, yaitu dengan penggunaan sistem monitoring temperatur tuang logam dan energi (daya kelistrikan) pada mesin tungku induksi saat proses pengecoran berlangsung. Sistem monitoring yang dirancang bertujuan untuk memudahkan operator menampilkan data secara real time, menyimpan, dan mengolah data serta mengevaluasi data pada cloud/server. Sistem ini diintegrasikan dengan menggunakan teknologi Internet of Things (IoT). Database parameter pengecoran (temperatur tuang dan penggunaan energi) yang didapat dari hasil pengukuran sensor-sensor dan tersimpan di cloud digunakan sebagai bahan analisis dan evaluasi penelitian di bidang pengecoran logam baja karbon dan besi tuang. Hasil analisis dari sistem monitoring ini diharapkan dapat membantu mengontrol penggunaan energi yang berlebihan di MIDC.

PT. Pilar Kekar Plasindo merupakan pabrik yang memproduksi kantong plastik dengan dua jenis produk plastik, yaitu plastik jenis Polypropylene (PP) dan Polyethylene (PE) dengan berbagai ukuran. Terdapat sepuluh area kerja di PT. Pilar Kekar Plasindo, dimana dalam proses produksinya memiliki risiko bahaya panas yang berasal dari lingkungan sekitar. Berdasarkan studi pendahuluan yang telah dilakukan diperoleh temperatur rata-rata pada ruang produksi PT. Pilar Kekar Plasindo sebesar 33,90C. Temperatur ini menyebabkan para pekerja di bagian produksi merasa tidak nyaman. Hal ini dibuktikan dengan hasil wawancara kepada para pekerja bagian produksi yang sering mengeluh dengan kondisi lingkungan kerja yang panas. Kondisi tersebut menyebabkan pekerja di bagian produksi cepat berkeringat, merasa kepanasan, tidak nyaman, cepat lelah, dan kurang fokus dalam bekerja. Pada ruang produksi dibutuhkan pemenuhan aspek kenyamanan termal untuk menunjang aktivitas didalamnya. Salah satu yang mempengaruhi kenyamanan termal adalah temperatur udara. Penelitian ini bertujuan untuk mengetahui kondisi lingkungan kerja berupa distribusi paparan panas pada ruang produksi PT. Pilar Kekar Plasindo melalui pemetaan menggunakan software surfer 11. Selain itu, untuk mengetahui tingkat kenyamanan termal pekerja sesuai dengan Keputusan Menteri Kesehatan No.1405/ MENKES/SK/XI/2002. Metode yang digunakan pada penelitian ini adalah pengukuran secara langsung berdasarkan SNI-16-7062-2004 dan ASHRAE 55. Waktu pengukuran dilakukan selama 6 hari kerja pada awal shift, tengah shift dan akhir shift berdasarkan SNI-16-7061-2004. Data yang diperoleh kemudian akan diolah menggunakan software surfer 11. Software surfer 11 digunakan untuk menggambarkan kondisi temperatur udara berupa peta kontur dari tiap area kerja pada ruang produksi PT. Pilar Kekar Plasindo, sehingga solusi yang diberikan diharapkan dapat memperbaiki lingkungan kerja kedepannya.

Awal ditemukannya prinsip refrigerasi pemakaianya hanya untuk produksi es sekarang seiring pesatnya kemajuan teknologi, refrigerasi memiliki peran sangat penting dalam produksi maupun distrubusi makanan, di samping untuk effisiensi operasi industri.Terdapat beberapa jenis makanan, sayuran, dan buah-buahan yang dapat disimpan dalam kondisi mentah, walaupun beberapa memerlukan proses awal. Refrigerasi seringkali memegang faktor kunci dalam proses ini industri – industri yang perlu keterlinbatkan teknik refrigerasi adalah industri susu (dairy products) yang menghasilkan milk, ice cream, dan mentega. Industri pengawetan daging dan daging unggas, pengawetan ikan saat pengapalan. Penelitian ini dilakukan untuk mengetahui efisiensi daya kompresor dengan diagram mollier pada mesin Trainer Cold Stroge, mengetahui cara kerja sistem refrigerasi, mengetahui nilai temperatur sebelum dan sesudah kompresor, mengetahui nilai entalphy sebelum dan sesudah kompresor, mengatahui komponen-komponen mesin pendingin dan cara kerja komponen – komponen mesin pendingin, perhitungan (COP) Coeffient of performance dengan perhitungan data temperature yang akurat dengan sistem sensor temperatur digital dan Micro controller Arduino uno sehingga dapat menghitung temperature yang akurat dan bisa digunakan memakai komputer, mesin ini bisa acuan bagi mesin pendingin yang lain karena sistem pada mesin ini sudah terautomasi dan moderet.

The effect of flow and temperature on the corrosion behavior of carbon steel in an aqueous methyldiethanolamine solution containing different heat stable salts, such as sodium sulfate, sodium sulfite and sodium thiosulfate, has been studied. The introduction of flow and increase in temperature generally caused an increase in the corrosion rate of carbon steel but the presence of the heat stable salts affected the corrosion behavior to different extents. Sulfate increased the corrosivity of the aqueous methyldiethanolamine solution, thus showed accelerated corrosion behavior in the presence of flow and with increase in temperature when compared with the solution without heat stable salts. The presence of sulfite reduced the corrosivity of the methyldiethanolamine solution due to its oxygen scavenging ability. Although flow and temperature stimulated an increase in the corrosion rate of carbon steel, the corrosion inhibiting effects of sulfite ions increased with the salt concentration. Also, the presence of sodium thiosulfate caused a reduction in carbon steel corrosion. Its inhibition ability is largely the result of the formation of FeS product layer resulting from its disproportionation reaction. This layer offered a slight resistance to the influence of flow and increase in temperature when compared with the system without heat stable salts. [ABSTRACT FROM AUTHOR]

Latar belakang: DBD adalah penyakit tular vektor yang paling serius di Kota Bandar Lampung. Virus dengue dan vektornya Aedes aegypti sensitif terhadap perubahan cuaca, khususnya curah hujan, temperatur dan kelembapan. Tujuan: Penelitian bertujuan mengetahui hubungan faktor cuaca dengan kasus DBD menggunakan periode tahun 2009-2018. Metode: Data diperoleh dari laporan jumlah kasus bulanan Dinas Kesehatan Kota Bandar Lampung, dan iklim harian dari Badan Meteorologi Klimatologi dan Geofisika yang dikonversi menjadi rata-rata bulanan. Perangkat SPSS 24.0 digunakan pada semua tingkatan analisis (CL=95%), termasuk Pearson Correlation, Spearman rank Correlation, dan Multiple Linier Regression. Hasil: Kami menemukan, kasus DBD tertinggi pada bulan Januari, Februari, dan Maret. Curah hujan berkorelasi positif dengan jumlah kasus DBD pada tahun 2011 (p-value=0,012), dan 2015 (p-value=0,020). Setiap tahunnya, periode hujan mendahului dimulainya waktu peningkatan kasus DBD. Temperatur berkorelasi negatif pada tahun 2014 (p-value=0,036). Kelembapan berkorelasi positif pada tahun 2014 (p-value=0,024), dan 2015 (p-value=0,018). Curah hujan memberikan pengaruh terbesar dalam hubungan dengan kasus DBD di Kota Bandar Lampung (36,9%). Kesimpulan: Temuan ini memberikan bukti empirik mengenai hubungan faktor cuaca dengan penularan DBD, dan diharapkan dapat memberikan landasan ilmiah untuk pencegahan dan penanggulangan DBD.

Cocoa seeds are recalcitrant with some problems in their storage system due to lack of dormancy period. This study aimed to find out the effect of cocoa pod storage in two different temperatures and the storage period towards seed viability and growth of the seedlings. This study applied a split-plot design with storage temperature as main plot and storage period as sub-plot. Cocoa pods of Sulawesi-1 clone were harvested and stored at 20ºC and 29ºC for 3, 7, 14, and 30 days. The stored cocoa seeds were then sown for three months. The findings showed that the storage of cocoa pods at 20ºC for 30 days causing the seed water content was 45%, the growth of the seedlings after the storage was 98.7%, and could press the pod shrinkage (1.6%). The storage of cocoa pods at 29ºC for 30 days could accelerate the reduction process by 68.2%, decreased germination of seeds up to 83.4%, and reduced the water content by 44.2%. The pod storage at 20ºC for 30 days showed a high value in some aspects such as seedling height, stem diameter, leaf area, seedling fresh weight, and shoot/root ratio. The storage of pods at 29ºC for 14 days indicated a high score in the character of germination, seedling height, stem diameter, and fresh weight of seedlings. The storage of pods at room temperature could be conducted for 14 days, meanwhile, at controlled temperature, it could be conducted for 30 days

Baja ASTM A36 tergolong ke dalam baja struktural, penggunaannya banyak dalam dunia industri misal konstruksi jembatan, struktur bangunan, roda gigi, dan konstruksi kapal. Baja ASTM A36 memiliki beberapa kekurangan yaitu kapasitas kedalaman pengerasannya yang rendah, ketahanan korosi yang buruk, dan sifat mekanik seperti kekerasan yang relatif rendah. Oleh karena itu, untuk menanggulangi permasalahan baja ASTM A36 maka dilakukan proses pengerasan permukaan menggunakan metode pack carburizing dengan menggunakan variasi temperatur 850, 900, dan 950ºC dan waktu tahan selama 2 jam menggunakan karbon aktif konvensional dan energizer dari cangkang telur. Pengujian yang dilakukan meliputi pengujian struktur mikro, dan pengujian laju korosi (polarisasi linier). Hasil yang diperoleh yaitu proses pack carburizing berpengaruh terhadap laju korosi dari baja ASTM A36 dengan ditunjukkan oleh penurunan laju korosi yang terjadi, sementara variasi temperatur pada proses pack carburizing terhadap laju korosi dari baja ASTM A36 tidak berpengaruh secara signifikan. Variasi temperatur optimal dalam proses pack carburizing terhadap laju korosi baja ASTM A36 diperoleh pada spesimen C1 dengan variasi temperatur karburisasi sebesar 850°C dan terjadi penurunan laju korosi sebesar 48,6% dari spesimen N (tanpa perlakuan).

De-icing of bridge decks, control of hardening or concrete strengthening through tempering are promising applications for active temperature induction into RC structures. The paper introduces fundamental approaches and devices: heating with infrared radiators, heating pads, heated water and Peltier elements, cooling liquids and dry ice, are discussed by means of nominal electric powers, attachment to the structure, interaction of device and structure, temperature control and potential losses. The characteristics of the approaches are analyzed and rated. A test series on insulated beams serves for reference. The alternative approaches are separately applied and combined to induce temperature gradients. Heating pads and infrared radiators are most suited for heating while Peltier elements and liquids are beneficial for cooling. From comparison recommendations for practical application are derived. [ABSTRACT FROM AUTHOR]

Investigation of actual temperature loads on concrete bridges – Determination of thermal strains Temperature loads are very relevant for the economic dimensioning of structural bearings and expansion joints. In addition, higher temperature loads lead to an increase in restraints when designing integral bridges. The development of a realistic temperature load model is therefore of great technical and economic importance. As part of the project "Modified Temperature Load Model for Railway Bridges (MTE 2.0)", which was initiated by the Austrian Federal Railways, long‐time temperature and deformation measurements were carried out on six concrete bridges. In addition, numerical transient simulations and comparative calculations were performed to investigate the thermal stresses, the temperature gradient and time‐dependent effects (creep, shrinkage). Finally, temperature data from the last 50 years of the Austrian Central Institute for Meteorology and Geodynamics were analyzed using probabilistic methods in order to optimize the correlation between shade air temperature and bridge temperature. These long‐term measurements, simulations and analyzes are the bases for an optimized temperature load model for concrete bridges, which is especially relevant for structures with low slenderness and massive cross‐sections without compromising the reliability of the structure. [ABSTRACT FROM AUTHOR]

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ABSTRAK Reactor Cavity Cooling System (RCCS) adalah salah satu sistem keselamatan pada Reaktor Daya Non Komersial (RDNK). Untuk mensimulasikan keadaaan tersebut, dibuat prototype Heater Element System (HES) yang merupakan sistem pemanas listrik dan berfungsi untuk memberikan kalor pada simulator dinding RPV (wall) seperti pada acuan RPV tipe HTGR. Tujuan penelitian adalah untuk memperoleh karakteristik temperatur selama pemanasan prototype HES hingga mencapai temperature 400°C berdasarkan posisi vertikal dan horizontal HES. Metode pengamatan dilakukan dengan menggunakan kamera infra merah NEC tipe TH9100ML sebagai alat ukur temperatur dan alat visualisasi ditribusi temperatur. Hasil pengamatan menunjukkan, bahwa kehilangan kalor pada prototipe HES pada posisi vertikal lebih kecil dibandingankan pada posisi horizontal hal ini disebabkan karena luas permukaan pada posisi horizontal sebesar 7,260 cm2 lebih memungkinkan untuk kehilangan kalor lebih besar. Posisi vertikal temperatur yang dicapai pada wall prototipe HES lebih tinggi dibandingkan pada posisi horizontal. Kata Kunci: RCCS, Heater Element System, kamera infra merah, temperatur ABSTRACT Reactor Cavity Cooling System (RCCS) is one of the safety systems in Non-Commercial Power Reactors (RDNK). To simulate this situation, a prototype Heater Element System (HES) was made using electric heating system as a heat sources and it serves to provide radiation heat to the RPV wall simulator as the reference of the RPV of HTGR type. The purpose of this study was to obtain the temperature characteristics during the heating of the HES prototype to reach temperatures of 400°C base on HES position, horizontal and vertical positions. The observation method was carried out using a TH9100ML infrared camera NEC type as a temperature measurement and a temperature distribution base on visualization. The observations show that the heat loss in the HES prototype in the vertical position is smaller than in the horizontal position because this is because the surface area in the horizontal position 7.260 cm2 is more likely to lose more heat. The vertical position the temperature achieved on the HES prototype wall is higher than in the horizontal position. Keywords: RCCS, Heater Element System, infrared camera, temperature

Jurnal ini menjelaskan tentang perhitungan cooling capacity yang dibutuhkan pada Kapal Tanker 17500 LTDW, perhitungan cooling capacity bertujuan untuk mengetahui daya compressor yang dibutuhkan pada system pendingin. Metode yang digunakan adalah menghitung cooling capacity berdasarkan GA (General Arranggement) yang mencakup beberapa parameter yaitu jumlah orang, jumlah jendela, volume ruangan, equipment, dan panas dari lampu. Sehingga didapatkan perhitungan Heat Calculation, Air Capacity, dan Cooling capacity pada sebuah kapal tanker. Hasil penelitian ini menunjukkan bahwa cooling capacity kapal Tanker 17500 LTDW sebesar 487,87 kW.

Indonesia memiliki hasil panen komoditas pertanian yang melimpah salah satunya adalah kedelai. Kedelai biasa digunakan dalam pembuatan makanan seperti tempe, tahu, kecap dan lain-lain. Pada proses pembuatan makanan tersebut kedelai mengalami proses pemanasan yang dapat mengurangi kandungan senyawa bioaktif pada kedelai. Suatu upaya yang dapat dilakukan untuk meningkatkan kandungan senyawa bioaktif pada kedelai yaitu dengan elisitasi. Elisitasi adalah suatu metode yang memberikan kondisi tidak nyaman pada tanaman menggunakan media atau senyawa (elisitor) sehingga dapat membentuk metabolit sekunder yang berfungsi sebagai media pertahanan. Elisitor dapat berupa biotik (mikroorganisme, jamur dan herbivora) dan abiotik (ion logam berat, angin dan sinar UV). Elisitasi dalam beberapa penelitian dapat menggunakan kejut listrik dan temperatur sehingga kombinasi kejut listrik dan suhu diharapkan dapat berpotensi dalam peningkatan pembentukan metabolit sekunder. Mekanisme yang terjadi yaitu pemberian cekaman (lingkungan yang ekstrem) oleh kedua faktor tersebut akan memicu pembentukan gen-gen dan hormon yang dapat memicu terbentuknya metabolit sekunder sebagai pertahanan diri.

Uji coba dapur pemanas terbuka dengan ukuran panjang 1100 mm, lebar 900 mm, tinggi 700 mm dan dinding terbuat dari bahan bata tahan api dan bata merah mampu menghasilkan temperatur panas 9250 C dibanding dengan dapur pemanas tertutup hanya mampu menghasilkan temperatur panas 7200C. Hasil uji kekerasan setelah logam ditempa panas dan dilanjutkan proses pendinginan oli, angka kekerasan tertinggi pada pendinginan oli SAE 40 sebesar 88 HRB dan angka kekerasan terendah pada pendinginan oli SAE 140 sebesar 85 HRB. Angka kekerasan semakin menurun disebabkan viskositas oli semakin kental, akibatnya laju pendinginan semakin lambat dan besar butirnya semakin kasar, sehingga logam mudah ditempa panas. Pengamatan struktur mikro pada bagian permukaan logam hasil tempa panas pendinginan oli dengan pembesaran 200 x secara umum lebih dominan terbentuk fasa ferit dibanding fasa perlit dan bagian melintang logam hasil tempa panas pendinginan oli dengan pembesaran 200 x, secara umum baja karbon rendah dan baja karbon tinggi telah menyatu. Fasa ferit sifatnya ulet, kekerasannya rendah dan fasa perlit sifatnya keras tetapi getas. Pada pendinginan oli tidak terbentuk fasa martensit yang sifatnya sangat keras dan getas, hal ini disebabkan pada saat proses pendinginan seluruh jenis oli fasa austenit tidak dapat bertransformasi menjadi fasa martensit. DOI: https://doi.org/10.26905/abdimas.v3i1.2248

The purpose of this research was to determined the shelf life of packaged palm sugar at various temperatures and relative humidity (RH) storage using Arrhenius model based on changes in water content. The palm sugars were packed with 0.675 mm polyethylene packaging and stored at 15, 25, 30 and 35°C at RH of 77% and 98%. Measured parameters included the determination of critical parameters of palm sugar, initial moisture content and critical moisture content of palm sugar, changes in moisture content during storage. The Arrhenius model approach was used in this study to predict the shelf life period of palm sugar. The results showed that the texture was one of palm sugar critical parameters. Initial moisture content and critical moisture content of palm sugar were obtained at 1.51% (db) and 6.80% (db), respectively. Increase in moisture content of palm sugar occurred in various temperature variations and RH storage. The higher the storage temperature, the higher the moisture content of the palm sugar, which was characterized by the greater slope of moisture content relationship graph with respect to storage period at both RH 77% and 98%. The longest duration of palm sugar occurred at 15°C, RH 77%; the shortest duration occurred at 35°C, RH 98%. Keywords: palm sugar, packaging, relative humidity, temperature, shelf life ABSTRAK Tujuan dari penelitian in adalah menentukan umur simpan gula semut dalam kemasan pada berbagai suhu dan RH penyimpanan mengunakan model Arrhenius berdasarkan perubahan kadar air. Gula semut dikemas menggunakan kemasan polietilen ketabalan 0,675 mm dan disimpan pada suhu 15, 25, 30 dan 35oC pada RH 77% dan 98%. Parameter yang diukur antara lain penetuan parameter kritis gula semut, kadar air awal dan kadar air kritis gula semut, perubahan kadar air selama penyimpanan. Pendekatan model Arrhenius digunakan dalam penelitan ini untuk memprediksi umur simpan gula semut. Hasil menunjukkan bahwa tekstur merupakan salah satu parameter kritis gula semut. Kadar air awal dan kadar air kritis gula semut diperoleh masing-masing 1,51 % (db) dan 6,80% (db). Terjadi peningkatan kadar air gula semut pada berbagai variasi suhu dan RH penyimpanan. Semakin tinggi suhu penyimpanan maka kenaiakn kadar air gula semut semakin besar yang ditandai dengan semakin besar kemiringan grafik hubungan kadar air terhadap waktu penyimpanan baik pada RH 77% dan 98%. Umur simpan gula semut paling lama terjadi pada suhu 15oC RH 77% dan umur simpan gula semut yang paling pendek terjadi pada suhu 35oC RH 98%. Kata kunci: gula semut, kelembaban relatif, kemasan, temperatur, umur simpan

Copyright of Technisches Messen is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)