Nature And Properties Of Soils

Global forest resources assessment 2000 : main report

Anthropometric measurements for ergonomic design of students’ furniture in India

Anthropometry is a key element of ergonomic studies for addressing the problem of fitting the tasks/products to user characteristics, but there is a gap between anthropometric data and their application for designing ergonomic products and environments. This research was conducted to review the literature on the methodology and applications of anthropometry for the ergonomic design of products and environments, and to identify where further research is needed to improve its application and evaluation protocols. One hundred and sixteen papers meeting the inclusion criteria were reviewed. Although a number of anthropometric investigations have been conducted to improve the design of products/environments for different users, further research seems to be necessary, particularly for special groups, such as children, the elderly and people with disabilities. Different anthropometric measurement methods/techniques and fitting criteria are discussed regarding their applicability for various design applications. This review also highlights methodological issues (sampling considerations and prototype evaluation and testing) that should be considered in future research to ensure a user-centred approach of the design process. Practitioner Summary: A literature review was conducted on the methodology and applications of anthropometry for the ergonomic design of products/environments. This review emphasises the need for anthropometric research to design for special groups, such as children, the elderly and people with disabilities, and methodological issues that should be considered in future research. Abbreviations: 1D: one-dimensional; 2D: two-dimensional; 3D: three-dimensional; HF/E: Human Factors/Ergonomics; PCA: Principal Components Analysis; CA: Cluster Analysis; DHM: Digital Human Modelling.

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A review of the methodology and applications of anthropometry in ergonomics and product design.

Motor-manual tree felling and processing (MMTFP) is among the most used options in timber harvesting operations and it is formally known to be a heavy job exposing the workers to safety hazards and harmful factors. Nevertheless, both workload and exposure depend on many operational, organizational, and worker-related parameters. Few studies have evaluated the ergonomics of such operations and fewer have been carried out using an integrated approach able to collect and interpret data for more than one ergonomic parameter. This study evaluated the ergonomic conditions of task-based MMTFP operations in flatland poplar forests by the means of workload, exposure to noise, and risk of musculoskeletal disorders. A fully-automatic approach was used to collect and pair the heart rate and noise exposure data that was complemented by video recording to collect postural data. Workload experienced by the worker was evaluated in terms of heart rate reserve (%HRR), indicating a heavy load during the productive time (%HRR = 46%); exposure to noise was calculated at the task and study level, exceeding (LAeq = 97.15 dB(A); LEX,8h = 96.18 dB(A)) the acceptable limits; and the risk of musculoskeletal disorders was evaluated using the concepts and procedures of the Ovako Working Posture Analysis System, indicating a high postural risk index (PRI = 275), which can cause musculoskeletal disorders (MSD). For more conclusive results, the research should be extended to cover the relevant variability factors.

Workload, Exposure to Noise, and Risk of Musculoskeletal Disorders: A Case Study of Motor-Manual Tree Feeling and Processing in Poplar Clear Cuts

In this study, the necessary anthropometric measurements of classroom furniture used in Turkish higher education were carried out. The static anthropometric measurements of 13 dimensions from 1049 students were obtained while they are standing and sitting. The data obtained was analyzed to determine the limit values to be used in classroom and laboratory design. The dimensions of school desks and chairs were compared with the student’s anthropometric measurements. For male students, the average weight was found as 69.50 kg, stature as 1749 mm, and popliteal height as 433 mm. For female students, the average weight was found as 56.02 kg, stature as 1618 mm, and popliteal height as 421 mm values. According to these anthropometric measurements, it was observed that there was a mismatch between popliteal height and seat height, knee height and desk clearance, buttock to popliteal length and seat depth. The percentile values concerning the ergonomic design of school desks and chairs in our classrooms were presented. The results show that there are significant differences between the anthropometric measures of Turkish students and other nations compared.

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An analysis of biomechanical and anthropometric parameters on classroom furniture design

The use of small-scale harvesting equipment continues to grow in forestry in many regions of the world. This equipment includes various devices and methods used to harvesting that generally are smaller, less expensive and less productive than advanced forestry machines. The objective of this study is to compare the efficiency of five alternative extraction methods implemented in a harvesting unit located in a mixed beech and oak forest ecosystem in northwestern Turkey. A continuous time study was conducted during primary transport operations that included skidding with animal power, skidding with farm tractor, hauling with farm tractor, hauling with forest tractor, and extraction by skyline. Timber was skidded uphill on a skid trail, and an average skidding distance of 100 m for all haulage methods was considered. Average slope of the harvesting unit ranged from 20 to 40 %. Average productivities for respective haulage methods were 3.80, 6.25, 2.80, 5.25 and 10.09 m3/h. Significant differences were found between productivity of haulage methods using one-way analysis of variance. The extraction by skyline, skidding with farm tractor, and hauling with forest tractor were determined to be the most statistically different methods, the productivity of these methods was found significantly higher than the other methods. Skid trails are useful for shortening distances during forest operations and skidding with farm tractor is a productive method in small-scale forestry of Turkey.

A Comparison of Productivity in Five Small-Scale Harvesting Systems

In this study, a total number of 114 workers who were in 3 different groups in terms of age and work underwent audiometric analysis. In order to determine whether there was a statistically significant difference between the hearing loss levels of the workers who were included in the study, variance analysis was applied with the help of the data obtained as a result of the evaluation. Correlation and regression analysis were applied in order to determine the relations between hearing loss and their age and their time of work. As a result of the variance analysis, statistically significant differences were found at 500, 2000 and 4000 Hz frequencies. The most specific difference was observed among chainsaw machine operators at 4000 Hz frequency, which was determined by the variance analysis. As a result of the correlation analysis, significant relations were found between time of work and hearing loss in 0.01 confidence level and between age and hearing loss in 0.05 confidence level. Forest workers using chainsaw machines should be informed, they should wear or use protective materials and less noising chainsaw machines should be used if possible and workers should undergo audiometric tests when they start work and once a year.

Noise induced hearing loss of forest workers in Turkey.

The soil-bearing capacity is one of the important criteria in dimensioning the superstructure. In Turkey, predictability of California Bearing Ratio values, which may be used in the planning and dimensioning of forest roads, of which about 26% lacks the superstructure, by using soil mechanical properties (cost and time efficient parameters that are easier to determine) is investigated. Simple linear regression, multiple linear regression, artificial neural networks and adaptive network–based fuzzy inference system methods were utilized. Two hundred sixty-four California Bearing Ratio values obtained from the project carried out on the forest roads of Bartin Forest Operation Directorate were used in both the production of training-test data and the creation of models. Statistical performance of the models was assessed by means of parameters such as root-mean-square error, mean absolute error and R2. The obtained results show that the bearing capacity values predicted by artificial neural networks and adaptive network based fuzzy inference system models display significantly better performance than the simple linear regression and multiple linear regression models. While the highest prediction capacity belongs to adaptive network based fuzzy inference system (0.969–0.991), it is followed by artificial neural networks (R2 = 0.796–0.974), multiple linear regression (R2 = 0.796) and simple linear regression (R2 = 0.554). What makes the algorithms superior than the traditional statistical models is the fact that they have many processing neurons, each with local connections, and thus have higher error tolerance. On the other hand, for the forest and rural roads, which play an important role in rural development of the forest peasants, to be able to operate all-seasons, superstructure should be immediately built in order to minimize the wear on the roads.

Prediction of soil-bearing capacity on forest roads by statistical approaches

Agricultural tractors in various types and dimensions are generally used in forest depots in Turkey for loading and stacking the forest products. In recent years, using machines for loading forest products has increased more and more due to the high productivity obtained from the machines and hardships in finding skilled workers. However, the risks accompanying these developments threaten the health of the operators working in loading machines. This study was applied on machines (145) working in loading and stacking operations in forest depots within the borders of the Western Black Sea Region. In the region, tractors on which loading equipment is mounted (85%) and original loading machines (15%) are used for loading and stacking operations. The average noise level that the operators were exposed to during the operations was above the hazard limit; for tractors without cabins on which the loading equipment is mounted, it was 93.5 dB (A) and with a noise level of 77.7 dB(A), it was below the warning limit for tractors with original cabins. In the operation, machines older than 20 years and/or machines with broken static and dynamic structures should be replaced. Instead of tractors with mounted loading equipment that are intensively used in the region and easily purchased due to their low cost, the use of original loading machines should be encouraged. In order to minimize the noise carried to the operators, the use of tractors with original cabins should be increased. While choosing places for forest depots, steeply sloped areas should be avoided, and the roughness of the ground should be reduced by covering the ground of existing depots with stabilized material.

	 

	Key words: Ergonomics, forestry, loading tractors, noise.

https://www.academicjournals.org/article/article1380896457_Melemez and Tunay.pdf

Metin Tunay

Papers

An analysis of biomechanical and anthropometric parameters on classroom furniture design

A Comparison of Productivity in Five Small-Scale Harvesting Systems

Noise induced hearing loss of forest workers in Turkey.

Prediction of soil-bearing capacity on forest roads by statistical approaches

The investigation of the ergonomic aspects of the noise caused by agricultural tractors used in Turkish forestry.