Hand Drill Research Articles

Особенности нормативно-методического обеспечения оценки профессиональных рисков

The objective of the study was to examine the peculiarities of practical application of the effective regulatory and legal documents used for occupational risk assessment. Regulatory and legal acts, methodological and guiding documents as well as state standards regulating occupational risk assessment have been analyzed; the application of certain methodologies of occupational risk assessment for employees of primary occupations engaged in copper and zinc ores extraction and processing was tested by two methods, i.e., the matrix method using the RiskProf online service and the method according to R 2.2.3969—23. The final assessment of the occupational risk of health disorders of employees of primary occupations was performed by the matrix method, considering a hazard (hazardous event), severity, and the probability of possible events. For all professional groups, the occupational risk assessed by the matrix method corresponded to the average level. The occupational risk assessment of employees’ health disorders in accordance with R 2.2.3969—23 demonstrated that the risk among employees of various occupations has been very high. The application of two methods of occupational risk assessment provided significant inconsistency in results. The risk analysis based on the retrospective data including earlier implemented risks in the form of occupational illnesses provided a more negative forecast; whereas the detected risks require a higher prioritization when developing measures to improve working conditions. As a result of the integrated occupational risk assessment, a very high risk category has been established for sinkers on hand drills (5 points), high for sinkers of drilling rigs and drivers of loading and delivery machines (4 points); for the other employees, the risk category complied with the average level. The obtained results demonstrate that only the use of both methodologies has ensured an objective occupational risk assessment considering expected (potential) and implemented risks.

Historical Quarry Landscapes of Three Finnish Granites

The quarry landscapes of Virolahti, Uusikaupunki, and Vehmaa are results of quarry operations during the most important periods of natural stone quarrying in Finland. The quarry landscape in Virolahti was formed in connection to the quarrying of red Virolahti pyterlite for the construction of St. Petersburg in Russia from the middle of 1700s to the beginning of the 1900s, while in Uusikaupunki, the quarry landscape is connected to the start of the modern Finnish stone industry and the National Romantic architecture at the beginning of the 1900s. The quarry landscape in Vehmaa is related to the start of the modern Finnish stone industry and export of Finnish granite at the beginning of the 1900s. In Virolahti, several small quarries can be seen, while in Vehmaa, a tendency towards fewer, but larger quarries start to emerge. In each area, human settlement was formed around the quarries. The geological basis for all areas is a rock type suitable for natural stone quarrying. The geotechnical features of each rock type indicate high resistance to wear and the products from these areas are early examples of durable construction. The quarry landscapes represent well the typical quarrying technology of the time and its development from channelling by chisels through hand drilling to mechanical drilling and blasting. The quarry areas form unique industrial and cultural heritage landscapes in Finland.

Hand drill shape optimization using Open CASCADE library and the steepest descent method

In this article, compliance optimization with the steepest descent method of the hand drill bits shapes for metal drilling is presented. The analysis of stress, displacements and compliance of the solid with random shape can be performed using the finite element method. In the case of a high number of optimization iterations, each analysis needs automatic modifications of geometry, mesh and boundary conditions. The Open CASCADE library can be used in the fast and automatic construction of modified models. It allows for fast reanalysis for each derivative of the objective function in the optimization process. The motivation of this research is to fill the gap in the literature on drilling technology. Most of the contemporary research is devoted to the oil and gas industry, while optimization of the hand drill bits used in metal drilling is rare. Compliance optimization allows us to find the shape which guarantees a greater stiffness for the specified loading conditions and a given amount of material. Although the obtained compliance was low, further experimental research would be needed to apply new solutions in drilling practice. This will involve the construction of the drill bit tips and the development of a heat treatment process

The Surgical Method of Craniectomy Differentially Affects Acute Seizures, Brain Deformation and Behavior in a TBI Animal Model.

Traumatic brain injury (TBI) is the leading cause of morbidity and mortality worldwide. Multiple injury models have been developed to study this neurological disorder. One such model is the lateral fluid-percussion injury (LFPI) rodent model. The LFPI model can be generated with different surgical procedures that could affect the injury and be reflected in neurobehavioral dysfunction and acute EEG changes. A craniectomy was performed either with a trephine hand drill or with a trephine electric drill that was centered over the left hemisphere of adult, male Sprague Dawley rats. Sham craniectomy groups were assessed by hand-drilled (ShamHMRI) and electric-drilled (ShamEMRI) to evaluate by MRI. Then, TBI was induced in separate groups (TBIH) and (TBIE) using a fluid-percussion device. Sham-injured rats (ShamH/ShamE) underwent the same surgical procedures as the TBI rats. During the same surgery session, rats were implanted with screw and microwire electrodes positioned in the neocortex and hippocampus and the EEG activity was recorded 24 hours for the first 7 days after TBI for assessing the acute EEG seizure and Gamma Event Coupling (GEC). The electric drilling craniectomy induced greater tissue damage and sensorimotor deficits compared to the hand drill. Analysis of the EEG revealed acute seizures in at least one animal from each group after the procedure. Both TBI and Sham rats from the electric drill groups had a significant greater total number of seizures than the animals that were craniectomized manually (p<0.05). Similarly, EEG functional connectivity was lower in ShamE compared to ShamH rats. These results suggest that electrical versus hand drilling craniectomies produce cortical injury in addition to the LFPI which increases the likelihood for acute post-traumatic seizures. Differences in the surgical approach could be one reason for the variability in the injury that makes it difficult to replicate results between preclinical TBI studies.

KAJIAN STUDI GEOTEKNIK KLASIFIKASI TANAH PERMUKAAN UNTUK PERENCANAAN PEMBANGUNAN DIKAWASAN UNIVERSITAS SAMUDRA

Soil classification is a science that aims to study ways to differentiate soil properties and divide soil into classes based on general characteristics. The aim of this research is to determine the physical properties of the land surface and determine the classification of surface land in the Samudra University area to be mapped based on soil type using ArcGis. 38 undisturbed soil samples were taken using a hand drill and 38 soil samples were tested in the laboratory to determine the physical properties of the soil and to map research results for surface soil types using Arcgis with the kriging interpolation method. From the test results, the lowest water content was at point 35 with a value of 4 55% and the highest was at point 5 with a value of 62 64%. The lowest liquid limit was at point 1 with a value of 15 65% and the highest was at point 13 with a value of 47 99% and the lowest plasticity index was at point 5 with a value of 5 70% and the highest at point 3 with a value of 26 93% while the lowest filter analysis was at points 10 and 12 with a value of 0% and the highest was at point 5 with a value of 40 74%. From the research results, it was concluded that the soil types in the Ocean University area received 7 classification groups based on AASHTO with the most dominant group being group A.2-6 with 19 points.

PROSES REPAIRING RACK SPAREPART MOBIL KHUSUS PART CRASH PAD MAIN ASSY

The car spare parts rack is one of the products ordered from PT. Y which is produced by PT. TH. Apart from that, PT. TH also accepts the shelf repair process if there is damage due to use. This research was conducted to find out the process of repairing car spare parts racks specifically for crash pad main assembly. The research method uses literature study and observation. Observations were carried out at PT. TH as the company in charge of repairing all rack spare parts from PT. Y. The shelf repair process generally includes steps to repair or restore the condition of damaged shelves, the process includes checking damage, measuring and cutting hollow steel for the shelf frame, welding process, cleaning welding marks, replacing shelf wheels, painting, installing parts. , installation of bases and roof racks, installation of rack covering mica, naming of racks and quality control process. Machines and equipment used in the shelf repair process include welding machines, grinders, hand drills, cutting wheels, compressors and anglers. This shelf repair procedure is in accordance with the SOP from PT. Y so that it can produce product improvements whose quality is guaranteed.

The Surgical Method of Craniectomy Differentially Affects Acute Seizures, Brain Deformation, and Behavior in a Traumatic Brain Injury Animal Model.

Traumatic brain injury (TBI) is the leading cause of morbidity and mortality worldwide. Multiple injury models have been developed to study this neurological disorder. One such model is the lateral fluid percussion injury (LFPI) rodent model. The LFPI model can be generated with different surgical procedures that could affect the injury and be reflected in neurobehavioral dysfunction and acute electroencephalograph (EEG) changes. A craniectomy was performed either with a trephine hand drill or with a trephine electric drill that was centered over the left hemisphere of adult, male Sprague Dawley rats. Sham craniectomy groups were assessed by hand-drilled (ShamHMRI) and electric-drilled (ShamEMRI) to evaluate by magnetic resonance imaging (MRI). Then, TBI was induced in separate groups, (TBIH) and (TBIE), using a fluid-percussion device. Sham-injured rats (ShamH/ShamE) underwent the same surgical procedures as the TBI rats. During the same surgery session, rats were implanted with screw and microwire electrodes positioned in the neocortex and hippocampus and the EEG activity was recorded 24 h for the first 7 days after TBI for assessing the acute EEG seizure and gamma event coupling. The electric drilling craniectomy induced greater tissue damage and sensorimotor deficits compared with the hand drill. Analysis of the EEG revealed acute seizures in at least one animal from each group after the procedure. Both TBI and Sham rats from the electric drill groups had a significant greater total number of seizures than the animals that were craniectomized manually (p < 0.05). Similarly, EEG functional connectivity was lower in ShamE compared with ShamH rats. These results suggest that electrical versus hand-drilling craniectomies produce cortical injury in addition to the LFPI which increases the likelihood for acute post-traumatic seizures. Differences in the surgical approach could be one reason for the variability in the injury that makes it difficult to replicate results between preclinical TBI studies.

Unveiling the potential of Moringa oleifera Lam. gums: An investigation into optimal tapping strategies

To optimize the best tapping technique for enhanced gum production with minimal injury to the trees, suitable Moringa oleifera Lam. trees were selected for experimentation, and the trees were treated with different tapping techniques for moringa gum production. When gum inducer was applied to trees treated with battery and hand-operated drills with ½ inch drill bit diameter and 1.0 in. drilling diameter, the gum yield was about fifteen times higher than when the inducer was not applied. It was about four times higher for trees treated with hand-operated drills and 1.0 in. drilling diameter. When employing the Gum tapping blazer-75 to develop a blaze, the average gum production was 1.29 times higher than when using a chisel. Bore hole developed with 1.0 in. diameter hand drill with inducer application yielded the highest total gum yield, followed by ½ inch diameter hand drill and ½ inch battery operated drill with inducer application, blaze developed with Gum tapping blazer-75, bore hole developed with 1.0 in. diameter hand drill without inducer application, blaze developed with chisel, bore hole developed with ½ inch hand drill without inducer application, and bore hole developed with battery operated drill having ½ inch drill bit without inducer application, respectively. A regular increasing trend in moringa gum yield was observed almost in all the treatments with an increase in environmental temperature, which indicates that moringa gum can be tapped throughout the year but a higher quantity of gum may be collected during April–September. When employing the Gum tapping blazer-75, blaze is produced on the tree trunk with ease and sharp edges. The use of developed blazer made blazing faster compared with blaze making using chisel. Gum production was higher with gum inducer technology than with any other method when it came to tapping moringa gum from Moringa oleifera trees using a hand drill. Data on quality characteristics determined for engineering can be used as references in development of equipments and machineries for processing and value addition of moringa gum while chemical properties for various applications in food, pharmaceutical and cosmetic industries for development of high value products.

Modified Tap-drilling Technique for Mid-cervical Pedicle Screw Placement: A Case Series of 473 Consecutive Screws.

Retrospective cohort study. To report our modified tap-drilling technique for mid-cervical pedicle screw placement and to evaluate its safety and accuracy. Cervical pedicle screw fixation, which provides a strong stabilization, has been a major concern due to the potential risks to neurovascular structures despite its increasing use. Several insertion techniques have been described so far to improve the cervical pedicle screw placement accuracy. This study retrospectively reviewed patients who underwent mid-cervical (C3-C6) pedicle screw fixation between September 2005 and September 2020. Laminectomy, laminoforaminotomy, or notch-referred anatomic landmark methods were used to adjust the entry point and the direction of the screws. After the cortical bone was removed at the entry point with a diamond burr, the cancellous bone was slowly drilled with a hand drill starting from 8 to 10 millimeters in length. Then, all of the bone walls were checked with a ball-tip probe to determine if there was any breach. The procedure was repeated several times. After completing the drilling, the screw was inserted without tapping. The breach rate of pedicle screws was analyzed on postoperative computed tomography scans. A total of 473 mid-cervical pedicle screws were placed in 122 consecutive patients. No navigation or computer-assisted system was used, and the first 2 authors inserted all of the screws. All patients completed the surgery, and no evident intraoperative complications occurred. Postoperative CT scans were obtained for 405 screws. Although deviation was observed for 131 pedicle screws, a critical deviation was observed for only 25 pedicle screws. Cervical pedicle screw insertion is a risky but applicable technique. Checking all of the bone walls with a ball-tip probe before gradually advancing the hand drill in small amounts, as presented in this article, may lead to the safe and effective placement of cervical pedicle screws.

A light-powered self-rotating liquid crystal elastomer drill

Self-oscillating systems can directly convert ambient energy to mechanical work, and new type self-oscillating systems are worth designing for applications in energy harvesters, engines, and actuators. Taking inspiration from the hand drill, we have developed a novel self-rotating drill system, which is consist of a turnplate and a liquid crystal elastomer (LCE) fiber under steady illumination. To investigate the self-rotating behaviors of the LCE drill, we have proposed a nonlinear theoretical model of the LCE drill under steady illumination based on the well-established dynamic LCE model. Numerical calculation reveals that the LCE drill can undergo a supercritical Hopf bifurcation between the static regime and the self-rotation regime. The self-rotation of drill originates from the contraction of winding portion of LCE fiber in illumination at winding state, and its continuous periodic motion is sustained by the interrelation between light energy and damping dissipation. The Hopf bifurcation conditions are also investigated in detail, as well as the vital system parameters affecting its frequency and amplitude. In contrast to the abundant existing self-oscillating systems, this self-rotating drill stands out due to its simple and lightweight structure, customizable dimensions, and high speed, and thus facilitates the design of compact and integrated systems, enhancing their applicability in microdevices and systems. This bears great significance in fields like micro-robotics, micro-sensors, and medical instruments, enabling the realization of smaller and higher-performance devices.

Tripod Fixation of Periacetabular Metastatic Lesions Using the IlluminOss Device.

Percutaneous tripod fixation of periacetabular lesions is performed at our institution for patients with metastatic bone disease and a need for quick return to systemic therapy. We have begun to use the IlluminOss Photodynamic Bone Stabilization System instead of the metal implants previously described in the literature because of the success of the IlluminOss implant in fixing fragility fractures about the pelvis. At our institution, the procedure is performed in the interventional radiology suite in order to allow for the use of 3D radiographic imaging and vector guidance systems. The patient is positioned prone for the transcolumnar PSIS-to-AIIS implant and posterior column/ischial tuberosity implant or supine for the anterior column/superior pubic ramus implant. Following a small incision, a Jamshidi needle with a trocar is utilized to enter the bone at the chosen start point. A hand drill is utilized to advance the Jamshidi needle according to the planned vector; alternatively, a curved or straight awl can be utilized. The 1.2-mm guidewire is placed and reamed. We place both the transcolumnar and posterior column wires at the same time to ensure that there is no interference. The balloon catheter for the IlluminOss is assembled on the back table and inserted according to the implant technique guide. The balloon is inflated and observed on radiographs in order to ensure that the cavity is filled. Monomer is then cured, and the patient is flipped for the subsequent implant. Following placement of the 3 IlluminOss devices, adjunct treatments such as cement acetabuloplasty or cryoablation can be performed. Alternative treatments include traditional open fixation of impending or nondisplaced acetabular fractures in the operating room, or percutaneous implant placement in the operating room. Implant placement may be performed with the patient in the supine, lateral, or prone position, depending on surgeon preference. Alternative implants include standard metal implants such as plates and screws, or cement augmentation either alone or with percutaneous screws. Finally, ablation alone may be an alternative option, depending on tumor histology. Open treatment of acetabular fractures is a more morbid procedure, given the larger incision, increased blood loss, longer time under anesthesia, and increased length of recovery. Percutaneous fixation may be performed in either the operating room or interventional radiology suite, depending on the specific equipment setup at an individual institution. At our institution, we prefer utilizing the interventional radiology suite as it allows for more precise implant placement through the use of an image-based vector guidance system and 3D fluoroscopy to accurately identify safe corridors. The use of percutaneous fixation allows for faster recovery and earlier return to systemic therapy. Because the IlluminOss implant is radiolucent, it allows for better evaluation of disease progression and can better accommodate nonlinear corridors or fill a lytic lesion to provide stability. Postoperatively, we expect the patient to be weight-bearing as tolerated with use of an assistive device. We expect the small incisions to fully heal within 2 weeks. Patients should be able to return to systemic therapy as indicated earlier than with an open procedure. The use of a hand drill with the Jamshidi needle and trocar can help adjust a drilled pathway and allow for close adherence to a planned vector.Vector guidance systems can be useful to fully capture the area at risk for fracture and to provide maximal stability with the expandable implant, but they are not necessary to perform the procedure.Placing both posterior implants at the same time can be helpful to avoid interference. This is accomplished by drilling and placing the guidewire for both implants prior to reaming and placing the balloon implant. CT = Computed tomographyPSIS = posterior superior iliac spineAIIS = anterior inferior iliac spine.

Low‐cost tools for large‐scale seed scarification: efficiency in two species from South American arid lands

The use of native plants for arid land restoration requires the application of pre‐germination treatments to alleviate seed dormancy mechanisms. As it is known, scarification allows several valuable species to overcome the primary forms of dormancy. However, supplying large quantities of scarified seeds at a low cost represents a significant challenge. In this context, our objective was to evaluate locally constructed machines accessible to people of degraded lands in a state of poverty. The effectiveness was evaluated by comparing two native shrubs from South American arid lands, Larrea divaricata and L. cuneifolia. Four treatments were applied: control (T0), mechanical scarification with a hand drill equipped with sandpaper on its head (T1), and mechanical scarification for 15 seconds (T2) and 30 seconds (T3) with a self‐constructed machine, capable of regulating pressure and speed. For both species, the germination probability was higher with T2 (0.82 ± 0.02) compared to T0 (0.28 ± 0.03) and T1 (0.65 ± 0.03). T3 presented intermediate values (0.75 ± 0.03) but did not differ significantly from T1 and T2. Our results show the effectiveness of a locally constructed seed scarification tool to upscale seed‐based restoration in arid lands.

Peatmass Change and Water Level Influencing Regenerated Melaleuca Forest after a Fire in U Minh Thuong National Park, Vietnam

Following the largest forest fire in Vietnam in 2002, various activities were undertaken to sustain the mangrove forest on peat soil remnants in the Mekong Delta region. These activities included promoting natural regeneration, afforestation, and rapid forest restoration measures, in addition to other protective measures such as rainwater retention to maintain moisture levels for fire prevention. However, two critical challenges emerged: allowing the forest to naturally regenerate would lead to annual forest fires but maintaining a constant water level through year-round water retention would harm biodiversity. The study was conducted in U Minh Thuong National Park to address forest regeneration. After a major forest fire in Vietnam, various measures were taken to promote forest regeneration, including afforestation, silvicultural solutions, and hydrological techniques such as rainwater storage to maintain humidity and prevent future fires. A hand drill was used to collect samples, and a total of 15 plots were set up to survey the growth of the forest at three peat thickness levels. At each of the three collection sites, samples of one kg were collected and labeled according to the site as UTM1, UTM2, and UTM3. The samples were then sent to the laboratory of the Southern Institute of Forestry Science for analysis. There was a relationship between the chemical indicators of peat and the evolution of the Melaleuca forest. Peat thickness and flooding regime significantly influenced the growth of the Melaleuca forest, while another identified relationship was between peat chemical indicators and forest growth. The chemical composition of peat water changed significantly due to the rainy and dry seasons, with nutrient content and pH affecting forest growth. Peat thickness and flooding regime were essential in regulating forest growth. These studies highlight the importance of considering multiple factors, such as peat thickness and chemical properties, when developing effective forest restoration strategies. By understanding the relationship between peat thickness, chemical properties, and forest growth, forest managers can develop targeted strategies to promote regeneration while minimizing negative impacts on biodiversity.

Study of Sediment Deposit Characteristics based on Geotechnical Properties and Geographic Information System (GIS) Approaches

Several sedimentation processes occur in the downstream area between river mouths and the sea. One of the effects of this sedimentation process is the occurrence of siltation around the coast. Not infrequently, this disrupts sea passages when the ship is about to head to the pier or go to sea. Kuala Beach is one of the locations in Pangkalpinang where the sedimentation process continues to occur enough to disrupt the smooth flow of sea traffic. This study aims to provide an overview and analysis of results related to sediment characteristics, spatial analysis of deposits, and predictions of deposition rates around Kuala Beach, Pangkalpinang City. This research was conducted using the following methods: 1) Method of investigating sediment characteristics by collecting data through field testing in the form of hand drills and laboratory testing, 2) Spatial analysis method by mapping the area of sedimentation based on the results of sediment characteristic tests using Agisoft Metashape and QGIS. The results of this study note that sediment deposits are dominated by sediments with sandy grain characteristics (SP symbol based on the Unified Soil Classification System) and a fine grain content (passing sieve number 200) of around 1-3%. The pattern of distribution of sediment deposits is known to have relatively flat contours and relatively uniform characteristics down to a depth of 1.5 m. The coefficient of grain uniformity (Cu) is in the range of 2.43-8.2 with the tendency of uniformity level getting higher to the southeast. The coefficient of grain gradation (Cc) is in the range of 0.44-1.64 with the tendency of the gradation level getting better to the southeast.

NITROGEN USE EFFICIENCY IN SUNFLOWER (HELIANTHUS ANNUUS L.) INFLUENCED BY VARIOUS FERTIGATION AND BED PLANTING TECHNIQUES

Low nitrogen fertilizer use efficiency and high losses of nitrogen are the critical challenges being faced by sunflower grower. To address these concerns, an experiment was carried out during spring 2021 at the Agronomic research area of the Agriculture University, Faisalabad. The randomized complete block design experiment was used with three replications under split plot arrangement. The 5m x 3m net plot size was kept with sowing procedures retained in the main plot and nitrogen application techniques kept in the sub plot. The experiment was planted on 20-02-2021. The matured crop was reaped on 18 June, 2021 manually. The single row hand drill was used to sow sunflower crop. The 75 cm line to line and 25 cm plant to plant distance was maintained. The results indicated that plant population ranged from 73 to 74 with maximum plant height of 174.33 cm, stem diameter (3.70 cm), head diameter (23.13 cm), number of achenes per head (1237.6), 1000-achene weight (68.17 g), highest biological yield (10.92 t ha-1), achene yield (3.22 t ha-1), harvest index (29.48 %) and protein contents (29.03 %) was observed in treatment where nitrogen was applied by fertigation method and sunflower was sown on beds. But maximum oil contents (41.78 %) were observed where nitrogen was side dressed and flat sowing technique was adopted for crop sowing. It is found that use of fertigation method of nitrogen application and bed planting techniques proved to be the best combination for improving growth, yield &amp; yield relating attributes and improve fertilizer use efficiency with lower nitrogen losses for sunflower (Hybrid-33) under agro-climatic conditions of Faisalabad.

PENGENALAN DAN PELATIHAN PENGAMBILAN SAMPEL TANAH DISTURBED DAN UNDISTURBED UNTUK SISWA SMK 7 BIDANG KEAHLIAN KONSTRUKSI JALAN, IRIGASI, DAN JEMBATAN

&lt;p&gt;One of the challenges faced by students from SMK is the learning atmosphere and learning system applied by PTV. This is due to the gap between the SMK curriculum and PTV. State Vocational High School (SMKN) 7 Semarang is one of the vocational schools located in the city of Semarang. SMKN 7 Semarang has 8 expertise competencies, one of which is competence in the field of civil engineering, namely Building Construction, Sanitation and Maintenance (KGSP) and Road, Irrigation, and Bridge Construction (KJIJ). Students of SMKN 7 Semarang already have a basic understanding of civil engineering, but when they enter the PTV world, they still experience difficulties in several fields. Therefore, to bridge and fill the gap from the SMK curriculum to PTV, it is necessary to introduce and train related fields of civil engineering, one of which is field testing. Semarang State Polytechnic as one of the universities has competent human resources to provide solutions to these problems. The PKM team provided introduction and training on the use of hand drill and vane shear tools used for soil testing. The hand drill is used to take disturbed and undisturbed soil samples, while the shear vane is used to determine the shear condition of the soil. After conducting the introduction and training activities, students can better understand how to use the test equipment. In addition, students also understand better in analyzing soil data obtained from testing.&lt;/p&gt;

Identification of candidate paleotsunami deposit from sediment layers drilled in Seubadeh located in South Aceh of Indonesia

This study is conducted to identify prehistoric tsunami deposit (paleotsunami) in Seubadeh village, located in South Aceh Regency, Aceh province, Indonesia. Regional morphologic and seismic characteristics suggest that Seubadeh village is an area that stores tsunami deposits, both new tsunami deposits and prehistoric tsunami deposits. Therefore, in this study, the search for paleotsunami deposits was carried out in Seubadeh village. The tsunami deposit samples were taken at several points in Seubadeh village using a hand drill with a depth of more than 2 m. Sediment classification of the collected samples using Troels-Smith method shows a candidate layer of paleotsunami tsunami deposit was found between two clay deposits. The layer is dominated by plant roots and shell material. In addition, the sediment samples were sieved using a mesh to evaluate the grain size distribution of clay, silt and sand. The results of the grain size distribution and color evaluation of the respective layer are presented. The results of the analysis of the particle size distribution in the sample and the color of the sample indicate that there are 2 layers that show characteristics as a paleotsunami deposit, namely at a depth of about 170-200 cm and 280-292 cm. The paleotsunami deposit found will be further characterized by an emission spectroscopic technique.

Identification possible preserved 2004 Indian Ocean tsunami deposit collected from Pulot Village in Aceh Besar Regency, Indonesia

Identification of the tsunami candidate layers deposited by the Indian Ocean tsunami in 2004 has been successfully performed in Pulot Village, located in Leupung district, Aceh Besar Regency, Aceh Province. Based on a study of tectonic activity before and after the earthquake, Pulot Village was reported as one of the potential locations for finding tsunami deposits. Tsunami sediment is collected by inserting a hand drill into the ground more than 1 m deep. The presence of the 2004 tsunami candidate layers was identified according to the Troels-Smith characteristics. Based on our visual analysis, the prospective tsunami layer is found at a depth of 4 cm with a thickness of 8-38 cm, which is characterized by fine-medium sized dark brown sand deposits on weathered paleo soil layers. The sharp boundaries with the layers above and below it and the presence of organic material (plant roots, stems and anthropogenic material) can also be clearly observed in the tsunami deposit layers. The candidate layer for the 2004 tsunami deposit found will be further studied geochemically using a laser-induced breakdown spectroscopy (LIBS) instrument.

Influence of the drill bit tip geometry on the rotary drilling process performed with a hand-held hydraulic drill

Abstract In the mining and construction industries, hand drills are used to carry out many processes related to excavation and auxiliary works. Hand drilling is commonly applied for making small diameter holes, especially in hard-to-reach places. In the case of manual drilling, an important parameter is drilling resistance, especially torque. Drilling tools are subject to wear, which has a negative impact on the process of drilling, including resistance and efficiency. A blunt tool lowers the drilling speed and puts more strain on the operator. The article presents the results of laboratory tests of selected parameters of the drilling process carried out with a hydraulic rotary drill. The tests were performed with the use of new drill bits as well as drills characterized by a various degree of wear. The tests were carried out for popular, frequently applied rotary drilling tools, on a unique laboratory stand that enabled setting the feed force and measuring the torque, rotational speed, drilling path, drilling speed as well as the in and out pressure of the drill. A number of characteristics were determined as a function of time and depth of the drilled hole. It was found that tool blunting affects the drilling process in various ways, whereas the intensity of this influence is determined by the type of blunting. The test results can provide a basis for developing a criterion for replacing a drill bit with a new one.

Monitoring and Control System of Parallel Loads Electricity Consumption Based on IOT

This paper discusses the design of a power consumption monitoring using telegrams and LCDs. Monitoring of electrical energy consumption is carried out for overconsumption does not occur as well as safeguarding the electronic devices used. The relay will automatically disconnect the power source in every room when the power is overloaded and this condition is reported via the internet network with the Telegram application. To monitor power usage, it is necessary to measure it. Measurement in this study used a digital multi-meter and the PZEM-004T sensor. Measurements were made on ten electrical loads including Lights, fans, laptop chargers, cell phone chargers, soldering iron, grinders, iron hand drills, drill bits, and circular grinding wheels. The test to compare PZEM-004T and multimeter has been done, resulting in voltage error values of 0.048-1.347% and current error values of 0-35.484%. From the error value obtained in this test, it can be concluded that the PZEM004T is suitable for measuring current and voltage. Automatic control in the relay works when rooms 1, 2, 3, or 4 experience power readings that exceed the desired capacity. It will automatically cut off the voltage from the source so that excess power does not occur, the goal is to protect an electric circuit.