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"ABSTRAKTeknik untuk mengetahui RFL remaining fatigue life memiliki beberapa cara antara lain dengan teknik thermography. Dalam studi ini telah dilakukan completely rotating bending fatigue testing sesuai dengan standart JIS Z2274 untuk mengukur nilai Nf Fatigue Life dan untuk mengestimasi nilai RFL dengan teknik thermography. Selama pengujian dengan teknik thermography, perubahan temperature benda uji pada titik kritis diukur dengan menggunkan infrared kamera. Dari hasil pengukuran perubahan temperature tersebut telah dilakukan estimasi nilai RFL. Material yang dipakai adalah S45C. Pengujian dilakukan dalam putaran 1600 rpm dengan kondisi suhu lingkungan 25 C. Akhirnya dapat disimpulkan bahwa nilai RFL hasil estimasi dengan teknik thermograpy sangat mendekati dengan nilai RFL hasil pengujian.

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ABSTRACTThere are several techniques to estimate the RFL remaining fatigue life such as thermography techniques. In this study, rotating bending fatigue testing has been done completely with the standard JIS Z2274 to measure the value of Nf Fatigue Life and to estimate the value of the RFL using thermography techniques. During the testing with the techniques, the positive of temperature gradient of the specimen at the critical point is measured by using the infrared camera. From the result of temperature change, the RFL value can be estimated. The material used is S45C. The test is carried out in 1600 rpm with ambient temperature of 25 C. Finally, it can be concluded that the estimated RFL value with thermograpy technique is very close to the value of RFL test result."

"This book, set within a social gerontology and transport behaviour studies paradigm, examines current debates and issues around transport for older people and its relationship to health and wellbeing for individuals and society as a whole."

"This book provides a concise discussion of fatigue crack growth (FCG) failure and lifing analysis methods for metallic aircraft structures and components. After a reasonably concise historical review, surveys are made of (i) the importance of fatigue for aircraft structural failures and the sources of fatigue nucleation and cracking, (ii) contemporary FCG lifing methods, and (iii) the Quantitative Fractography (QF) required for determining the actual FCG behaviour. These surveys are followed by the main part of the book, which is a discussion, using case histories, of the applicabilities of Linear Elastic Fracture Mechanics (LEFM) and non-LEFM methods for analysing service fatigue failures and full- and sub-scale test results. This discussion is derived primarily from the experiences of the Defence Science and Technology Group in Melbourne, Australia, and the Netherlands Aerospace Centre, Marknesse, the Netherlands."

"ABSTRAKFatigue strength merupakan poin penting yang perlu diperhatikan dalam dunia keteknikan. Fatigue strength dipengaruhi oleh korosi, kekasaran permukaan, dsb. Terdapat beberapa metode yang bisa digunakan untuk meningkatkan fatigue strength, salah satunya yakni dengan surface treatment seperti heat treatment, ultrasonic impact treatment, Galvanisasi dsb. Dalam studi ini, simulasi untuk memprediksi fatigue life terhadap galvanized and non-galvanized S45C dengan menggunakan metode elemen hingga (commercial software) telah dilakukan untuk mengetahui besar pengaruh dari galvanized material dan non-galvanized spesimen. Hasil dari simulasi didapatkan bahwa nilai fatigue strength dari non-galvanized spesimen adalah sekitar 95% dibandingkan dengan data dari eksperimen. Lalu simulasi dilanjutkan untuk galvanized spesimen. Fatigue strength dari galvanized specimen sekitar 25% lebih tinggi dari non-galvanized spesimen. Sehingga bisa disimpulkan bahwa software bisa digunakan untuk memprediksi fatigue strength.

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ABSTRACT

Fatigue strength is an important point that needs to be considered in the world of engineering. Fatigue strength is affected by corrosion, surface roughness, etc. There are several methods that can be used to increase fatigue strength, one of them is surface treatments such as heat treatment, ultrasonic impact treatment, Galvanization, etc. In this study, a simulation to predict the fatigue life of galvanized and non-galvanized S45C by using the finite element method (commercial software) has been carried out to determine the effect of galvanized material and non-galvanized specimens. The results of the simulation show that the fatigue strength value of non-galvanized specimens is about 95% compared to the data from the experiments. Then the simulation is continued for the galvanized specimen. Fatigue strength of galvanized specimens is about 25% higher than non-galvanized specimens. So it can be concluded that software can be used to predict fatigue strength."

"In 2011, massive flooding and inundation in the Chao Phraya River basin, in Thailand, caused

serious damage to various activities for a prolonged period of time. Although snapshot images of

the inundated area are available, detailed information including temporal changes of the inundated

areas and the relationship with meteorological and hydrological conditions are not well

documented, particularly for the middle and upper sections of the basin. Therefore, we conducted

an analysis using two types of satellite data, HJ-1A and Envisat, to better understand behavior of

the large-scale inundation occurred in 2011, focusing on the middle section of the Chao Phraya

River basin. In the analysis, water surface in selected domains was extracted using the NDWI value

calculated from HJ-1A data. The threshold value of the Envisat ASAR image was then adjusted so

that the inundated area estimated from Envisat gives the closest possible match with that estimated

from HJ-1A. Finally, the inundated area was estimated for the whole study domain based on the

same threshold value from the Envisat data. Results indicated that the inundated area began to

extend along the Yom and Nan rivers in early August and continued to spread down to the Nakhon

Sawan city area until October. A significant increase in inundated areas occurred between Sep. 2

and Sep. l3, during which higher rainfall intensity was observed. Even after the water level in

rivers receded below the bank-full elevation, large areas were left inundated along rivers,

particularly over lowlying marsh and paddy fields. In addition, several areas located far from

rivers were also inundated, which was likely a consequence of water ponding in paddy fields."

"The aim of the present study is to estimate some mortalitymeasures such as the age specific death rates (ASDRA), infantmortality rate (IME) and me table crude death rate (CDR) for male,female and both sexes of Bangladesh in 2005. For this purpose, twoabridged life tables, one for male and other for female wereconstructed using the corresponding secondary data on lifeexpectancy at birth of Bangladesh in 2005 taken from Islam (2003).These were compared to the values in 199] and it was observed thatthese rates were showing decreasing trend during 1991-2005.Moreover, a mathematical model was fitted to the number ofpersons surviving at an exact age x (lx) only for male of Bangladeshin 2005. Model validation technique, cross validity predictionpower (C VFP) and F-test, showed that the mathematical model wasvalid and hence, fit is well. Instantaneous force of mortality ( |J. X )only for male of Bangladesh in 2005 was estimated And it wasfound that |.L X exhibited decreasing trend up to age 20-24 andincreasing in the remaining age group but rapidly increasing afterage 50 years to infinity."

"Quality of work life sangat penting untuk diteliti di PT ACS karena mengalami peningkatan kasus yang mengacu pada indikator quality of work life. Penelitian ini bertujuan untuk menguji pengaruh self-efficacy dan safety climate terhadap quality of work life dan pengaruh tidak langsung melalui mediasi perceived fatigue. Data empiris dikumpulkan dari 628 pelaut di PT ACS, dengan menggunakan metode survei online. Studi ini di analisis menggunakan Structural Equation Modeling (SEM) dan confirmatory factor analysis untuk menguji tujuh hipotesis yang diajukan. Hasil penelitian menunjukkan bahwa Self-efficacy dan safety climate berpengaruh positif terhadap quality of work life secara langsung. Dengan demikian, penelitian ini menunjukkan bahwa self-efficacy dan safety climate penting untuk quality of work life pelaut, memiliki efek langsung positif signifikan. Selain itu, dukungan self-efficacy juga terbukti berpengaruh negatif terhadap perceived fatigue. Lebih lanjut, penelitian ini diharapkan dapat memberikan kontribusi bagi pengambil kebijakan di bidang sumber daya manusia untuk mengidentifikasi self-efficacy dalam rekrutmen dan seleksi talenta serta menciptakan safety climate di tempat kerja untuk meningkatkan quality of work life.

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Quality of work life is very important to study at PT ACS because there has been an increase in cases that refer to indicators of quality of work life. This study aims to examine the effect of self-efficacy and safety climate on quality of work life and the indirect effect through mediation of perceived fatigue. Empirical data was collected from 628 seafarers at PT ACS, using an online survey method. This study was analyzed using Structural Equation Modeling (SEM) and confirmatory factor analysis to test the seven proposed hypotheses. The results of the study show that self-efficacy and safety climate have a positive effect on the quality of work life directly. Thus, this study shows that self-efficacy and safety climate are important for seafarers' quality of work life, have a significant positive direct effect. In addition, self-efficacy support has also proven to have a negative effect on perceived fatigue. Furthermore, this research is expected to contribute to policy makers in the field of human resources in identifying self-efficacy in talent recruitment and selection and creating a safety climate in the workplace to improve the quality of work life."

"Untuk mengetahui kekuatan struktur doubler dalam menahan terjadinya kegagalan akibat retakan yang disebabkan oleh cyclic loading, diperlukan suatu analisis tersendiri yang tidak terdapat pada panduan Structural Repair Manual (SRM). Cyclic loading dapat mengurangi kekuatan skin doubler secara bertahap (fatigue) hingga mencapai kegagalan (fracture). Pada penelitian ini akan dilakukan analisis crack growth rate dan jumlah siklus pembebanan yang dibutuhkan untuk memunculkan retakan dengan panjang tertentu (fatigue cycle) terhadap struktur doubler fuselage skin pesawat Boeing 737-900 Extended Range dengan station number 360-380 di antara stringer 6L-7L pada setiap panjang retakan dan ketinggian terbang simulasi. Analisis dilakukan menggunakan pendekatan numerik dengan metode Modified Virtual Crack Closure Integral (MVCCI) untuk mendapatkan nilai Stress Intensity Factor (SIF) melalui software berbasis metode elemen hingga. Melalui nilai yang diperoleh dapat diketahui bahwa nilai crack growth rate dan fatigue cycle berbanding lurus terhadap variasi panjang retakan dan ketinggian terbang simulasi yang diberikan. Nilai crack growth rate paling rendah terjadi pada struktur doubler dengan panjang retakan 8,5 mm dan kondisi terbang 5000 feet yaitu sebesar 2,964 mm/cycle, dan nilai tertinggi sebesar 5,471 mm/cycle terjadi pada struktur doubler dengan panjang retakan 51 mm dan kondisi terbang 40000 feet. Sedangkan, nilai fatigue cycle paling rendah terjadi pada struktur doubler dengan panjang retakan 8,5 mm dan kondisi terbang 40000 feet yaitu sebesar 2,540 cycle, dan nilai tertinggi sebesar 5,470 cycle terjadi pada struktur doubler dengan panjang retakan 51 mm dan kondisi terbang 5000 feet."

"Pekerja operator pesawat angkut merupakan pekerjaan yang sangat berisiko terjadi dehidrasi dan penurunan fungsi ginjal karena sebagian besar pekerja di PT X pada waktu istirahat lebih memilih untuk bertahan di dalam kabin pesawat angkut daripada beristirahat di base camp serta banyak pekerja yang tidak membawa minum saat bekerja. Penyakit ginjal kronis memberikan efek terhadap biaya kesehatan yang sangat besar dan penurunan tingkat produktivitas. Oleh karena itu, diadakan program hidrasi di PT X. Program hidrasi dilakukan dengan cara pekerja dianjurkan mengkonsumsi air 2,5 L saat bekerja. Program hidrasi dilaksanakan selama 1 tahun. Metode: Penelitian dilakukan dengan desain kohort retrospektif. Untuk membandingkan perubahan nilai GFR menggunakan uji perbandingan rerata (untuk data numerik) serta Uji McNemar (untuk data kategorik). Untuk menilai faktor yang berhubungan terhadap perubahan GFR digunakan analisis regresi logistik. Hasil: Fungsi ginjal pada operator pesawat angkut setelah program hidrasi antara 2019 dan 2021 mengalami perbaikan (mc nemar p< 0,001).Analisis bivariat menunjukkan bahwa factor individu yang berpengaruh terhadap perubahan fungsi ginjal adalah obesitas. Kesimpulan: Terdapat peningkatan fungsi ginjal pada operator pesawat angkut setelah kebijakan program hidrasi antara 2019 dan 2021.Program hidrasi dengan 2,5 L air selama 1 tahun dapat memperbaiki status dehidrasi pada pekerja dan berbeda bermakna pada pekerja non obes.

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Crane operator workers are very risky for dehydration and decreased kidney function. Most of the workers in PT X during their break prefer to stay in the cabin of the transport plane rather than rest at the base camp, and many workers do not bring a drink to work. Chronic kidney disease affects enormous health costs and reduced productivity levels. Therefore, a hydration program was held at PT X. The hydration program is carried out so that workers are advised to consume 2.5 L of water while working. The hydration program is implemented for one year. Methods: The study was conducted with a retrospective cohort design. We compared changes in the value of GFR before and after the hydration program using the mean comparison test (for numerical data) and McNemar's test (for categorical data). A logistic regression test was performed to assess the factors associated with changes in GFR. Results: Kidney function in crane operator workers after the hydration program policy between 2019 and 2021 were improved (McNemar p <0.001). Bivariate analysis shows that the individual factors affecting kidney function changes were obesity. Conclusion: There was improved kidney function in crane operator workers after the hydration program policy between 2019 and 2021. A hydration program with 2.5 L of water for one year can enhance the status of dehydration in workers and significantly different in non-obese workers."