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The problem lies in the inconsistent quality of M10 hexagonal head bolts with a spacing of 1.5 mm, a bolt length of 100 mm and slow production speed for manual production. The purpose of the analysis is to obtain consistent, standard, and productive quality of M10 hexagonal head bolts with a spacing of 1.5 mm, a bolt length of 100 mm. The analysis method includes the selection of AISI 1040 raw materials with a diameter of 10 mm in the form of rolls, the determination of the production process through raw material inspection, diameter reduction from 10 mm to 9.8 mm, the formation of hexagonal heads with a machine, cutting the length of the bolts and the bolt end chamfer, making M10 threads with a range of 1.5 mm with a machine, hardening, 10 m thick Zinc coating, thread profile inspection, sample hardness test, and sample tensile test. The results of mass production with the machine obtained a hexagonal head bolt with a thread size of M10x1.5 mm, a bolt length of 100 mm, a capacity of 500 units/hour in accordance with the ISO 9001:2015 standard with a hardness of 30 HRC and a tensile strength of 830 MPa at a cost of Rp. 1133/bolt and a process duration of 8.3 minutes/bolt which implies that product quality can be more guaranteed to be consistent and uniform.

The demand for lightweight materials with high mechanical strength has driven the development of aluminum alloys, particularly Al-Mg-Si, through deformation processes such as cold rolling. This study aims to analyze the effect of varying degrees of cold rolling deformation on the grain aspect ratio and macrohardness of homogenized Al-Mg-Si alloys. Deformation was applied at three thickness reduction levels—5%, 10%, and 20%—followed by microstructural characterization using optical microscopy and macrohardness testing in accordance with ASTM E-18 standards. The results show that increasing deformation levels lead to elongated grain morphology, with the grain aspect ratio rising from 1.16 to 2.07 and macrohardness increasing from 46.64 HRE to 62 HRE. The emergence of slip lines and grain flattening indicates the occurrence of intense plastic deformation, while work hardening results from dislocation accumulation that impedes further slip motion. These findings confirm a strong correlation between microstructural evolution and mechanical property enhancement in cold-deformed Al-Mg-Si alloys. This research contributes to the optimization of cold rolling parameters to produce engineering materials with a desirable balance of strength, formability, and fatigue resistance for applications in the mining and heavy manufacturing industries.

Spring steel is one type of material that is widely used in various engineering applications, such as vehicle suspension systems and equipment that require resistance to dynamic loads. Spring steel possesses various mechanical characteristics that are strongly influenced by the microstructure of the material. These characteristics remain consistently affected throughout the entire material. Heating that occurs due to exposure to flame can alter certain microstructural properties of spring steel and affect its performance. In this study, an analysis was carried out on all changes in the microstructure of spring steel caused by flame heating, as well as its effect on the hardness of the material. The results of the study showed that heating can indeed cause changes in the microstructural phase and a decrease in fatigue resistance of the spring steel.

Hypertension or high blood pressure is defined as a continuous increase in blood pressure that exceeds normal limits (Nuraini et al., 2023). Hypertension occurs due to several factors, the first being modifiable and non-modifiable factors. Among the modifiable risk factors for hypertension are smoking and obesity. People who smoke more than one pack of cigarettes per day will be twice as vulnerable as people who do not smoke (Luh et al., 2020). The purpose of this study was to determine the correlational between smoking and BMI with the incidence of hypertension in adult men in Alassumur Lor Besuk Probolinggo. The research design used an Correlational Analytic with a cross-sectional approach. The population in this study was 35 with a total sampling technique. The research instrument used a questionnaire, then the data obtained will be tested by Spearman rank. The results of the study obtained the smoking variable ρ = 0.018, the BMI variable ρ = 0.071. This shows that there is a corelation between smoking behavior and BMI with the incidence of hypertension. Smoking behavior that is increasingly uncontrolled will cause hypertension and accumulation of fat on the walls of blood vessels can cause narrowing and hardening, increasing blood flow resistance and ultimately increasing blood pressure. It is hoped that respondents will reduce their smoking habits and start a healthy life by maintaining a diet, exercising regularly and eating nutritious foods.

Linux kernel security is a critical aspect of ensuring the integrity and stability of operating systems. Vulnerabilities like Dirty COW (CVE-2016-5195) illustrate how exploitative threats can severely impact systems, particularly those that are not regularly updated. This study analyzes the working mechanism of Dirty COW, its impact, and mitigation strategies based on Linux kernel hardening techniques, including the use of security modules like SELinux and AppArmor, as well as the Address Space Layout Randomization (ASLR) technique. Through attack simulations and mitigation evaluations, the findings emphasize the importance of regularly applying kernel patches to maintain system security. This study aims to provide practical guidance for enhancing Linux kernel resilience against exploitation attacks.