Stability analysis of mathematical model on the effect of modern lifestyles towards the immune system

During the last century, lifestyles have changed globally not only in the western countries but also in the developing countries. As a result, the percentages of common fatal diseases, such as obesity, diabetes, cardiovascular disease, and cancer, have dramatically increased, especially in youth. This paper aims to mathematically examine the impact of modern lifestyle on health. Furthermore, we formulate a dynamical model for the impact of a balanced diet, regular exercise and sufficient sleep on the immune system and its processes. We present a stability model of the immune system that includes a cycle of phase-specific vitamins. Ordinary differential equations are used to model the system to describe the functioning of immune cells. The model considers three populations: normal cells, immune cells, and vitamin interventions. The results show that a balanced diet and a healthy lifestyle can boost the immune system and improve its processes to protect a human body from pathogens. In conclusion, a balanced diet and physical activity reduce the percentage of fatal disease risk. Furthermore, it is vital to raise awareness about healthy habits and promote healthy eating, especially for the youth

THE CONTRIBUTION OF UPPER LIMB JOINTS IN THE DEVELOPMENT OF RACKET VELOCITY IN THE BADMINTON SMASH

The contributions of the upper limb joints in developing the racket-head velocity were calculated using the 3D video analysis technique. The performance of 13 male players in the single and double competitions during the Thomas/Uber Cup 2000 was recorded. The major contributor to the mean racket-head's linear velocity of 34.6 ms·1 at impact was the wrist (26.5 %). The statistical analysis carried out showed that the dynamics of wrist served to increase the speed of the racket at impact. However, the study showed no significant correlation between the racket speed at impact and the velocity· of the shuttlecock after impact. A relationship between racket speed and post-impact acceleration of shuttlecock did exist

DETERMINATION OF TORQUES AT UPPER LIMB JOINTS DURING JUMPING IN BADMINTON SMASH VIA KANE’S METHOD

The paper discusses determination of torque forces at the upper limb joints, namely shoulder, elbow and wrist, using 2-dimensional Kane’s mathematical model of a three-link system, comprises of upper arm, lower arm and hand-racket segments. A planar threelink kinematic chain model is developed and the inverse dynamic method is applied. Kinematic data from 2 professional badminton players in a Thomas Cup’s Tournament are taken as input in the dynamics equation and torques calculated. The result shows that the elbow joint produced the highest value of torque during contact while performing the jumping smash activity

A STUDY ON THE ACCURACY OF THREE-DIMENSIONAL SPACE RECONSTRUCTION FOR POLES SYSTEM ON A 6 x 6 m2 FIELD

An investigation on space reconstruction error for the poles system, which covers an area of 6 x 6 m2 field, is carried out using a three video camera system. Two sets of location for the poles are tested. The result of the RMS error shows a superiority of the positioning the control points at the corners of the court, compared to that of the sides of the court

MUSCLE ACTIVITY DURING GAIT ON A TREADMILL: A COMPARISON BETWEEN ANTERIOR CRUCIATE LIGAMENTS (ACL) AND NORMAL SUBJECT'S

The aims of this research are to investigate and compare the muscles activity during gait on a treadmill for ACL subjects who underwent surgery and did not undergo surgery, and comparing them with normal subjects. The question that need to be solved is do the ACL subject who underwent or did not undergo surgery shows similar muscles force compared to normal subject? Walking activity of 12 subjects on a treadmill were captured using Vimn Nexus system and electrompgraphy (EMG) and analyzed. As a result, the comparison between ACL subjects shows that subject who underwent and did not undergo surgery used mainly soleus and gluteus maximus muscles, similar to normal subjects but the muscle forces produced were different. Besides, range of all ACL subjects' muscles who went through surgery was found to be similar to normal subject's

EFFECTS OF VARYING BACKPACK LOADS ON TRUNK INCLINATION DURING LEVEL WALKING IN CHILDREN

Several studies have been completed to determine the effects of backpack load on the dchanges of posture and gait pattern. The study on the trunk posture usually consists of the trunk inclination angle and range of motion. The purpose of this paper is to study the effects of load carriage on the trunk inclination angle of children while walking with different loads. Two male subjects, aged 6 years old were asked to walk at their comfortable speeds while carrying their schoolbags with load 0%, 10%, and 20% of body weight. The children were required to walk on an 8 m track a few times before their movement was recorded. The result showed that carrying heavy load of 10% and 20% of body weight induced a significant increase in forward lean of the trunk

ANALYSIS OF BACKPACK RESPONSE TO TRUNK MOTION DURING LOAD CARRIAGE ACTIVITY

A backpack vibration system consists of a backpack?human trunk system, was developed to examine the backpack’s response to trunk motion when carrying a load and to determine which damping and stiffness parameters give the best result for a stable backpack vibration system. The vibration system was analysed using different values for the damping and spring coefficients in the displacement and velocity equations of the backpack vibration system. Given a backpack mass of 3.5 kg, the vibration system oscillates with a stable condition damping value of c = 2 Nsmm-1 and a stiffness value of k = 5 Nmm-1

THE ANALYSIS OF THE JUMPING SMASH IN THE GAME OF BADMINTON

An investigation on the prevalence of jumping smash in a badminton game is carried out using a six video camera system. The data was collected during the Thomas/Uber Cup 2000 competition, which was held in Kuala Lumpur, Malaysia. Thirteen male players in the single and double competitions were studied. The trials were digitized using the Peak Motus 2000 system. The result from the chi square analysis showed that majority of the jumps and landing occurred in only one foot. And from the correlation analysis, it was found that the angular velocity of the ankle at the maximum value prior to take off was strongly correlated with the center of mass vertical velocity (r =0.546, P =0.001)

A COMPARATIVE STUDY ON KINEMATICS PARAMETERS BETWEEN THE SEPAK KUDA SERVE AND THE SEPAK SILA SERVE IN SEPAK TAKRAW

The most important and effective skill in a sepak takraw game is the serve. In 1995, during the 18th SEA Games, a new technique of serving, 'sepak kuda' was introduced. The sepak kuda serve is well known as the most powerful serve compared to the more traditional serve of 'sepak sila'. The purpose of this study was to make a comparative study on kinematics parameters in both techniques in order to identify specific characteristics of the serves and consequently to give gUidelines for training and mastering especially on the new technique to coaches and players

THREE-DIMENSIONAL CINEMATOGRAPHIC ANALYSIS: ENLARGING A CALIBRATED VOLUME

Doing research in open games requires a calibrating system as large as the size of the playing court. In this paper a new reference structure, poles system, which could encompass the size of a playing court, is developed. Comparisons between the currently available frame and the poles systems are made. The results showed that the poles are comparable to those obtained using the Peak calibration frame, despite the difference in the dimensions of the structures, the location of the control points, as well as the physical characteristics of the structures