Hammer Handle Research Articles

Data of clinical otorhinolaryngologic review of servicemen of armed forces of Ukraine are at implementation of the educational firing

Lately medical help is provided in many medical institution of Ukraine for those servicemen who suffered of the influence of intensive noise during implementation of duties of military service. Before sending in the zone of battle actions for implementation of the assigned tasks, servicemen of certain military branches pass training for improving of their skills, including, handling a weapon. The actual task is to reveal in time violations that can lea to the development of defeat of the auditory system under action of sounds of high intensity in the conditions of realization of battle actions in future. Aim: to define changes in otorhinolaryngologic status of servicemen of AFU during the implementation of the educational firing on a polygon. Materials and methods: the otorhinolaryngologic inspection of 53 servicemen is conducted at age from 18 to 37 and after realization of firing from a rifle armament (gun-machine of Kalashnikov without and with subbarrel grenade launcher) on a polygon. Results and their discussions: After realization of series of shots in parts of servicemen certain changes were revealed in ENT status. During the otoscopy of some patients (11.3%) was revealed the injection of the vessels by the way of handle of hammer, in 5 (9.4%) cases during the otoscopy was marked certain smoothness of the contours of eardrums and reduction of light reflex. Worth mentioning that 10 (18.8%) patients inspected after training felt high-frequency subjective noise. 2 fighters (3.7%) ment ioned moderate dizziness after implementation of shots. 5 (9.4%) servicemen had complaints about a moderate headache after training. Majority of them noted that such a feeling passed during an hour after firing. However, in 7.5% cases such complaints took the place after this term. And exactly at this group of inspected we also looked after changes at an otoscopy. We guided such fighters at a further instrumental inspection for detection of possible violations in functioning of auditory analyzer as a result of the noise influence. To our opinion, such persons should be examined in relation to the presence of preclinical violations in an auditory analyzer and possible increase of individual sensitiveness to noise influence . There is a risk, which in the zone of battle actions in case of acousticbarotrauma the severe defeat of the auditory system can develop in such fighters. Thus, due to the conducted examination by otolaryngologist. increases the possibility of revealing the person with high sensitiveness to the noise influence in time that help determine the limitations that can be applied in this case, It is expedient to use possibility to prevent development of heavy hearing loss and invalidisation of servicemen, that has socio-economic consequences. Conclusions: 1. During the implementation of the educational firing some servicemen can suffer from the violations of the state of the auditory system, which looks like the changes of otoscopic picture and the presence of complaints such as congestion of the ears, dizziness, high-frequency subjective ear noise, headache. 2. The examination of otolaryngologist after implementation of the educational firing of servicemen allows revealing those who has visible changes in the state of ENT-organs. The selection of such persons creates precondition of determination among them group of high risk further development of violations in an auditory analyser.

Real-time processes in the development of action planning

Across species and ages, planning multi-step actions is a hallmark of intelligence and critical for survival. Traditionally, researchers adopt a "top-down" approach to action planning by focusing on the ability to create an internal representation of the world that guides the next step in a multi-step action. However, a top-down approach does not inform on underlying mechanisms, so researchers can only speculate about how and why improvements in planning occur. The current study takes a "bottom-up" approach by testing developmental changes in the real-time, moment-to-moment interplay among perceptual, neural, and motor components of action planning using simultaneous video, motion-tracking, head-mounted eye tracking, and electroencephalography (EEG). Preschoolers (n= 32) and adults (n= 22) grasped a hammer with their dominant hand to pound a peg when the hammer handle pointed in different directions. When the handle pointed toward their non-dominant hand, younger children ("nonadaptive planners") used a habitual overhand grip that interfered with wielding the hammer, whereas adults and older children ("adaptive planners") used an adaptive underhand grip. Adaptive and nonadaptive children differed in when and where they directed their gaze to obtain visual information, neural activation of the motor system before reaching, and straightness oftheir reach trajectories. Nonadaptive children immediately used a habitual overhand grip before gathering visual information, leaving insufficient time to form a plan before acting. Our novel bottom-up approach transcends mere speculation by providing converging evidence that the development of action planning depends on a real-time "tug of war" between habits and information gathering and processing.

Effect of Hammer Type on Generated Mechanical Signals in Impact-Echo Testing.

The impact-echo diagnostic method is a well-known nondestructive pulse compression test method, which can be relatively easily used for the testing of concrete and reinforced concrete elements. The evaluation of the measurement with this method is based on the analysis of the signal itself in the time and frequency domains. This allows acquisition of information on the velocity of the mechanical wave, the resonant frequency of the specimen or on the presence of internal defects. The ability to interpret these measurements depends on the experience of the diagnostic technician. The advent of classification algorithms in the field of machine learning has brought an increasing number of applications where the entire interpretation phase can be considerably simplified with the help of classification models. However, this automated evaluation procedure must be provided with the information of whether the signal acquired by the test equipment has actually been measured under optimally set conditions. This paper proposes a procedure for the mutual comparison of different measuring setups with a variable tip type, hammer handle and impact force. These three variables were used for a series of measurements which were subsequently compared with each other using multi-criteria evaluation. This offers a tool for the evaluation of measured data and their filtering. As an output of the designed method, each measurement is marked by a score value, which represents how well the acquired signal fit the weight demands for each observed feature of the signal. The method allows the adjustment of selected demands for a specific application by means of set thresholds. This approach enables the understanding of characteristics of the signal in the automated pre-processing of measured data, where computing power is limited. Thus, this solution is potentially suitable for remote long-term observations with sensor arrays or for acoustic emission signals pre-processing.

Measurement of coupling forces at the power tool handle-hand interface

This study explored a low-cost system for measurement of coupling forces imposed by the hand on a handle under static and dynamic conditions, and its feasibility for applications to hand-held power tools. The properties of thin-film, flexible and trim-able resistive sensors (FlexiForce) were explored in view of their applicability for measurements of the hand-handle interface forces. The sensors showed very good linearity, while considerable differences were evident in the sensitivity amongst different sensors. The appropriate locations of the sensors on the handle surface were subsequently determined on the basis of the hand-handle geometry and reported force distributions. The validity of the measurement system was investigated for measuring the hand grip and push forces with eight subjects grasping five different stationary instrumented handles (cylindrical: 32, 38 and 43 mm diameter; and elliptical: 32 × 38 and 38 × 44 mm) considering two different positions of the sensors on the handle. The validity of the measurement system was also investigated under vibration for the 38 and 43 mm diameter cylindrical handles. The results showed good linearity and repeatability of the sensors for all subjects and handles under static as well as vibration conditions, while the sensors' outputs differed for each handle. The feasibility of the measurement system was also examined for measurements of hand forces on a power chisel hammer handle. The evaluations were conducted with three subjects grasping the power chisel handle under stationary as well as vibrating conditions, and different combinations of hand grip, push and coupling forces. The measurements revealed very good correlations between the hand forces estimated from the FlexiForce sensors and the reference values for the stationary as well as the vibrating tool. Relevance to industryThe measurement of hand-handle interface forces is vital for assessing the hand-transmitted vibration exposure and musculoskeletal loads. The low cost and flexible sensors, proposed in the study, could be conveniently applied to the curved surfaces of real power tool handles in the field to measure hand grip and push forces, and the forces exerted on the palm and the fingers. The most significant benefits of the sensors lie with its minimal cost and applicability to the real tool handles.

The role of object affordances and center of gravity in eye movements toward isolated daily-life objects.

The purpose of the current study was to investigate to what extent low-level versus high-level effects determine where the eyes land on isolated daily-life objects. We operationalized low-level effects as eye movements toward an object's center of gravity (CoG) or the absolute object center (OC) and high-level effects as visuomotor priming by object affordances. In two experiments, we asked participants to make saccades toward peripherally presented photographs of graspable objects (e.g., a hammer) and to either categorize them (Experiment 1) or to discriminate them from visually matched nonobjects (Experiment 2). Objects were rotated such that their graspable part (e.g., the hammer's handle) pointed toward either the left or the right whereas their action-performing part (e.g., the hammer's head) pointed toward the other side. We found that early-triggered saccades were neither biased toward the object's graspable part nor toward its action-performing part. Instead, participants' eyes landed near the CoG/OC. Only longer-latency initial saccades and refixations were subject to high-level influences, being significantly biased toward the object's action-performing part. Our comparison with eye movements toward visually matched nonobjects revealed that the latter was not merely the consequence of a low-level effect of shape, texture, asymmetry, or saliency. Instead, we interpret it as a higher-level, object-based affordance effect that requires time, and to some extent also foveation, in order to build up and to overcome default saccadic-programming mechanisms.

Study on coated–liquid–liquid trimetal composite casting hammer

In order to solve the problems of the fracture of the hammer head and the poor wear resistant of hammer handle in working conditions, the coated liquid–liquid trimetallic composite casting hammer was proposed. The core handler needed to be coated by high impact toughness and high wear resistant liquid high carbon high chromium steel to improve wear resistant of hammer handle. Then liquid high chromium cast iron was poured when the surface of liquid high carbon high chromium steel formed into certain thickness solid. The experimental results show that the wear resistant of the high carbon high chromium is as 3·2 times as low alloy steel. The perfect metallurgical bonding interface under the liquid–solid volume ratio of 8∶1 can be achieved by liquid–solid casting at 1565°C after the preheating 300°C.

Research on the New Combined Type Crusher Hammer

To solve the problems of installed trival, resource waste, hammerhead falling off and improve the poor abrasion resistance of hammer handle under the crusher hammers working condition, the new combined type crusher hammers were designed by connecting separated hammer handle and separated hammer head. When hammer head were worn badly, we just replaced hammer head and don't have to remove the shaft rod. This design can save a lot of time and labor force, improve production efficiency and we can save a lot of resources by reusing the hammer handle; At the same time, hammer tip was casted with liquid-liquid bimetal composite casting technology of casting, under the premise of guaranteeing the wear-resisting, which can also ensure that the impact toughness of the joint. Validated by actual working condition, hammer handle can be replaced at least five times for this design of hammer, and each group has 24 hammer heads, every 5 sets of hammer heads can save 1200 kg metallic materials, 1800 KWh and CO2 emissions dropped by 1795 kg.

Study on Bimetal Compound Casting Technology of Hammers

For the characteristics of the hammer handle is under bending stress and impact constantly alternating and the the main of the hammer is Withstand strong impact and friction in use，the paper designed a new type of composite casting process of hammerhead. It has two wear block imbedding in the below of the hammer ，and it set in on both sides of the axis of the hummer wiche with Inverted trapezoidal dovetail structure. The wear block was cast by high chromium cast iron, and it is properly heat treatment and surface cleaning before casting, but Into the mold after re-heated to temperature above 600 °C，At the same time，poured into the cast high-manganese steel quickly，so the block and hammer handle fused together，the block of composite hammer does not wear off in the use, and the wear resistance of the hummer improved significantly.

Improving Products’ Ergonomic Value Using Intelligent Decision Support System

During the process of defining suitable design solutions, a designer has to consider a wide range of influential factors. Ergonomics certainly belongs to more complex ones. Less experienced designers could encounter several problems during this design stage. Although some literature can be found about ergonomic design of hand tools, a designer still has to have amassed quite a lot of experience and knowledge in the field of ergonomic, in order to choose and carry out appropriate design and redesign actions. Existing computer tools for ergonomic design are not able to assist a designer with higher level advice within design process. An intelligent decision support system has been developed in order to overcome this bottleneck. This paper presents a knowledge base, containing ergonomic design knowledge specific for hand tools design. A pneumatic hammer handle design is used as a case study to show how ergonomic design knowledge built in the system is used to improve the ergonomic value of the product.

Ergonomic design knowledge built in the intelligent decision support system

Existing computer tools for ergonomic design are unable to assist designers with higher level advice within design processes. Thus, design engineers need to rely on their own knowledge and experience when making crucial decisions relating to products’ ergonomic parameters. An intelligent decision support system has been developed in order to overcome this bottleneck. This paper presents a knowledge base, containing ergonomic design knowledge specific for hand tool design. A pneumatic hammer handle design is used as a case study in order to show how ergonomic design knowledge built within this system is used to improve the ergonomic value of a product. Relevance to industry Engineers in small and medium-size enterprises (SME's) or young designers are in an unenviable position as their knowledge domains and experiences are minimal. When applying decision support system discussed here, even SME's could appear on the market with optimal designed products with relatively minor influence on development budget. Consequently their role on the market will be aggrandised.

Determining the effectiveness of grazing and trampling by livestock in transmitting white clover mosaic and subterranean clover mottle viruses

SummaryGlasshouse and mini‐sward experiments were done to determine the relative roles of grazing and trampling by livestock in transmitting white clover mosaic (WC1MV) and subterranean clover mottle (SCMoV) viruses between clover plants in pastures. Wounding due to grazing was simulated by repeatedly cutting plants with serrated scissors (glasshouse) or mowing (mini‐swards), while wounding due to trampling was simulated by repeatedly bashing plants with the flat end of a wooden hammer handle (glasshouse) or rolling (mini‐swards). In glasshouse experiments, cutting was more effective than bashing in transmitting WC1MV to white clover (Trifolium repens) plants but cutting and bashing transmitted it to subterranean clover (T. subterraneum) plants at similar rates. In an experiment with white clover mini‐swards, mowing was more effective than rolling in transmitting WC1MV, and when both were combined, initially spread exceeded that obtained when the spread from mowing and rolling alone was added together. In glasshouse experiments, bashing was more effective than cutting in transmitting SCMoV to subterranean clover plants. In one experiment, neither mowing nor rolling spread SCMoV in mini‐swards of subterranean clover. When transmission to subterranean clover cultivars which were ‘susceptible’ or ‘moderately susceptible’ to SCMoV was compared in glasshouse experiments, repeated bashing spread the virus more slowly to the ‘moderately susceptible’ cultivars. When mixed with ruminant saliva, infective sap containing WC1MV or SCMoV was still infective to clover plants after 4 wk storage at room temperature. When infective sap was allowed to dry naturally on a metal surface, SCMoV still infected clover plants when the dried sap was taken up in tap water after 4 but not 14 days, while WC1MV was infective after 24 h but not 4 days.These results suggest that grazing and mowing are more effective than trampling at transmitting WC1MV to white clover plants in pastures, while trampling is more effective at spreading SCMoV to subterranean clover. However, both transmitted WC1MV to subterranean clover at similar rates. Possible reasons for these differences are discussed in relation to differences in clover plant morphology and virus‐specific factors.

Studies on the clinical signs of imparment of conductive apparatus due to noise

The author have studied on the clinical signs of impairment of conductive apparatus due to noise in laborers in the extremly noisy sections of a big automobile works in Japan. Morita's otoscopic goniometer modulated by author was used to measure the degree of retraction of ear drum. Reduction of conductive function was principally examined by Onchi's occluded bone conduction method. Following conclusions were obtained:1) By the exposure to noise, the conductive apparatus is more or less impaired besides perceptive apparatus in most of the cases, and its conductive function is reduced almost in half of them.2) The otoscopic findings of impaired conductive apparatus due to noise are retraction of ear drum, and injection of vessels in upper-posterior ouadrant or along the handle of hammer of ear drum. It seems that the retraction of ear drum plays a little role in the decrease of conductive function but injection of vessels plays some role in it.3) According to the various tests, it seems that there are some disorders of occicular chain due to noise and decrease of conductive function based mainly upon these disorders.4) In audiogramm of air conduction, it is found that the hearing loss of the ear which is accompanied by decrease of conductive function is little larger in lower and middle tonerange and is little smaller in high tonerange especially at 4, 000cps than that of the ear which conductive function is not reduced. But it is impossible to find out the decrease of conductive function by only the audiogramm of air conduction on each ear.

A NEW AID IN THE DIAGNOSIS OF MASTOIDITIS

It may be of interest to know what induced us to institute the investigation which we are reporting here. Some time ago, a woman, aged 52, came to us with a moderately acute inflammation of the middle ear. The landmarks in the tympanic membrane were not obliterated, and we did not feel that there was any indication for myringotomy. During the course of our observations, the evidences of inflammation of the ear disappeared. The light reflex returned, and the hearing became acute. The congestion about the hammer handle disappeared. Three weeks after the condition of the middle ear had returned to normal, the patient came back to the office with a tender, edematous swelling near the posterior border of the mastoid. At the operation, pus could not be observed macroscopically in the mastoid cavity. There was, however, a large erosion of bone; the sinus for an area of at least