DESAIN DIDAKTIS MATERI AJAR HUKUM KEKEKALAN MOMENTUM SUDUT BERDASARKAN HAMBATAN BELAJAR SISWA SMA KELAS XI

Dewasa ini, kebanyakan penelitian hanya fokus pada media, metode, dan model pembelajaran, namun kurang memerhatikan konten dari materi yang akan diajarkan. Sehingga, kurang memerhatikan hambatan-hambatan belajar yang dialami siswa dalam pembelajaran. Materi ajar hukum kekekalan momentum sudut merupakan materi fisika yang dianggap sulit oleh siswa karena mereka tidak mampu memahami konsep, memasukkan variabel kedalam persamaan, melakukan perhitungan matematis, dan memberikan analisis pemanfaatan hukum kekekalan momentum sudut. Penelitian ini bertujuan untuk mengetahui hambatan-hambatan yang bersifat epistimologi dan mencari desain didaktis terbaik untuk konsep hukum kekekalan momentum bagi siswa SMA kelas XI berdasarkan hambatan-hambatan yang dialami oleh siswa. Desain didaktis awal disusun berdasarkan hasil TKR (Tes Kemampuan Responden) pada kelas XII dan implementasi desain dilakukan di kelas XI. Penelitian dilakukan pada sekolah yang sama, dengan asumsi bahwa siswa-siswi setiap tingkatan kelas pada sekolah tersebut memiliki kemampuan belajar yang relatif sama. Setelah dilakukan dua kali implementasi desain dan tiga kali revisi desain, diketahuilah beberapa hambatan siswa yang bersifat epistimologis dan didapatlah desain didaktis akhir yang dapat digunakan oleh para guru sebagai pedoman ataupun referensi dalam pembelajaran materi ajar hukum kekekalan momentum sudut di kelas.;---Nowadays, a lot of researches just focus on medias, methods, and instructional models, but few researchers care about the content of the material. Therefore, they don’t care about learning obstacles students undergo during the learning procces. The conservation of angular momentum is one of physics branch which students impress as one of the most difficult because they lack of understanding the concept, lack of aranging the variables to the equation, lack of doing mathematical calculation, and lack of giving analitical explanation about the benefit of the concept. The purposes of this research are for knowing students epistimological obstacles and arranging the best didactical design of the conservation of angular momentum law for Senior High School student grade 11 based on students learning obstacles. The initial didactical design was arranged based on RCT (Respondents Capability Test) that given to the 12 grade students and the design was implemented to the 11 grade students. This research was done on the same school by assumtion that students’s learning capability at every levels of grade are relatively same. After twice implementations and three times design revised were done, it shows some epistimological obstacles and gives the eventual didactical design which can be used by teachers as an orientation and refference on teaching the conservation of angular momentum law

Power-efficient adaptive behavior through a shape-changing elastic robot

The adaptive morphology of a robot, such as shape adaptation, plays a significant role in adapting its behaviors. Shape adaptation should ideally be achieved without considerable cost, like the power required to deform the robot’s body, and therefore, it is reasonably considered as the last resort in classical rigid robots. However, the last decade has seen an increasing interest in soft robots: robots that can achieve deformability through their inherent material properties or structural compliance. Nevertheless, the dynamics of these types of robots is often complex and therefore it is difficult to substantiate whether the cost like the required power for changing its shape will be worthwhile to achieve the desired behavior. This article presents an approach in the development and analysis of a shape-changing locomoting robot, which relies on the ability of elastic beams to deform and vibrate. Through a proper use of elastic materials and the robot’s vibration-based dynamics, it will be shown both analytically and experimentally how shape adaptation can be designed such that it leads to desirable behaviors, with better power efficiency compared to when the robot solely relies on changing its control input. The results encourage emerging direction in robotics that investigates approaches to change robots’ behaviors through their adaptive morphology. </jats:p

Is the dewatering of Palm Oil Mill Effluent (POME) feasible? Effect of temperature on POME's rheological properties and compressive behavior

The current treatment process of Palm Oil Mill Effluent (POME) has been a cause of concern over recent years as POME is known to cause greenhouse gas emission as well as water pollution. An alternative for POME treatment process optimization is to eliminate the conventional cooling ponds and introduce a dewatering device such as a thickener. The thickener will assist in the solid-liquid separation, removal of microbes and other impurities from the wastewater. The latter will contribute to making the anaerobic digesters used to treat POME more efficient by allowing a means of control on the digesters’ load. However, to be able to design and predict the performance of the thickener unit; essential rheological properties of the suspension have to be determined. The rheological characteristics and the compressive behavior of POME have not been studied previously nor has the implementation of such a dewatering device in the POME treatment process. This paper attempts to bridge the gap on the rheological characteristics, the compressive behavior and the effect of temperature on the rheological properties of POME through batch settling and batch filtration experiments. Data such as the compressive yield stress, the hindered settling function, and the diffusivity function for POME have been extracted and evaluated

Instantaneous Segmental Energy Symmetry Index as Gait Compensation Indicator in Asymmetrical Walking

Purpose: Human body constantly adapts to optimise the energy expenditure. A better understanding of the mechanical energetic costs in lower extremities helps identify the compensatory mechanism adopted in asymmetrical gait. This paper proposes the use of instantaneous segmental energy and normalised symmetry index (SInorm) to examine asymmetrical gait. This approach can provide better overview of gait quality allowing identification of change in segmental energy during different gait phases and contribution of each segment in compensating abnormal walking. Method: An experimental study was carried out to validate this method. Twenty healthy subjects were recruited. Asymmetrical gait was simulated by restricting knee motion during walking using a knee brace. Mechanical energy was determined for each segment of the left and right limbs. Normalised Symmetry Index (SInorm) was then calculated to examine bilateral differences in segmental energy during stance phase and swing phase. Statistical analysis using ANOVA and Tukey-Kramer multiple comparison test to identify asymmetry of the segmental energy (p-value &lt; 0.05). Result: Significant asymmetry of segmental energy occurred during swing phase. Greater asymmetry was observed in kinetic energy than in potential energy. The affected limb segments produced lower kinetic energy than the normal limb. At asymmetrical state, potential energy of the affected limb’s foot and thigh were lower than that of the normal segments while the inverse was true for thigh segment. Conclusion: These results suggested that in asymmetrical gait, a form of compensatory mechanism is adopted to walk. This can be observed in the change of instantaneous segmental energy during walking

Evaluation of gait symmetry in poliomyelitis subjects : Comparison of a conventional knee ankle foot orthosis (KAFO) and a new powered KAFO.

Background: Compared to able-bodied subjects, subjects with post polio syndrome and poliomyelitis demonstrate a preference for weight-bearing on the non-paretic limb, causing gait asymmetry. Objectives: The purpose of this study was to evaluate the gait symmetry of the poliomyelitis subjects when ambulating with either a drop- locked knee ankle foot orthosis (KAFO) or a newly developed powered KAFO. Methods: Seven subjects with poliomyelitis who routinely wore conventional KAFOs participated in this study, and received training to enable them to ambulate with the powered KAFO on level ground, prior to gait analysis. Results: There were no significant differences in the gait symmetry index (SI) of step length (P=0.085), stance time (P=0.082), double limb support time (P=0.929) or speed of walking (p=0.325) between the two test conditions. However, using the new powered KAFO improved the SI in step width (P=0.037), swing time (P=0.014), stance phase percentage (P=0.008) and knee flexion during swing phase (p≤0.001) compared to wearing the dropped locked KAFO. Conclusion: The use of a powered KAFO for ambulation by poliomyelitis subjects affects gait symmetry in the base of support, swing time, stance phase percentage and knee flexion during swing phase

Perencanaan dan pembuatan mesin pemisah beras kapasitas 100 kg/jam

Di daerah pedesaan, padi yang diolah menjadi beras setelah melalui proses penggilingan dan pemolesan umumnya langsung dimasukkan kedalam proses pengepakan sehingga kualitas beras yang dihasilkan tidak begitu bagus karena terdapat banyaknya campuran antara beras kepala, beras patah serta menir. Dan akibatnya harga jual beras menjadi turun serta harga padi juga menjadi turun. Mesin ini menggunakan 4 (empat) tingkatan yang mana pada tingkatan pertama untuk menghasilkan beras kepala, tingkatan kedua untuk beras campuran antara beras kepala dan beras patah, tingkatan ketiga untuk menghasilkan beras patah dan terakhir adalah menir. Dalam perancangan mesin pemisah ini juga terdapat sebuah poros eksentris yang berfungsi untuk mengatur gerakan maju mundur sehingga proses pemisahan dapat berlangsung. Mesin yang direncanakan menggunakan motor 0,5 HP dengan putaran 1410 rpm, sedangkan putaran mesin yang dirancang sebesar 350 rpm untuk memisahkan beras dengan kapasitas sebesar 100 kg/jam

Real-time wireless ambulatory gait monitoring system incorporating online periodical gait evaluations

Human gait analysis studies the coordination of human lower extremity in providing propulsion to move forward while maintaining the body balance, with one foot in contact with the ground at all time. Hence, gait analysis plays an important role in clinical settings and rehabilitations. It is widely performed to identify various gait disorders, to assess the functional performance of a patient’s lower limb before and after a surgery or medical treatment, and to evaluate patient’s rehabilitation progress. In engineering, its importance is reflected in the design and development of the prosthetic limb, Functional Electrical Stimulation (FES) system as well as the humanoid robot. Optical motion capture system and force platform are commonly used in gait analysis to quantify human motion. However, these systems are expensive, bulky and can only capture human motion in a dedicated environment i.e. laboratory. As an alternative, this thesis developed a real-time gait monitoring system that utilizes wireless miniature gyroscopes. The miniature gyroscope is small, light-weight, and can capture human motion in both indoor and outdoor environments. More importantly, it is equipped with wireless data transmission, which offers additional benefits. Wireless gyroscope provides relatively larger movement area. It also does not obstruct the natural motion of human lower extremity. Apart from the advantages offered by the wireless gyroscopes, this system also uses several novel methods to assist clinicians and researchers in identifying abnormal gait. These methods evaluate three main aspects of human gait. They are referred as the gait normality test, gait asymmetry analysis, and the estimation of gait dynamic stability. Gait normality test examines a person’s gait relative to normal/healthy individual’s gait that was established by other researchers. Gait asymmetry analysis is an evaluation that examines the bilateral differences between the left and right limbs.The estimation of gait dynamic stability determines human walking stability using nonlinear time series analysis. It uses short-term and long-term maximum Lyapunov exponent to quantify the ability of human neuromuscular locomotor system in maintaining body balance during walking. Experimental study was also conducted to examine the overall capability of this system. This study simulated the abnormal gait by placing a load on one side of the limbs and by wearing a sandal on one foot. These methods successfully altered the inertial property of a person’s lower limb, hence inducing significant differences in spatio-temporal gait parameters between the affected limb and the non-affected limb. As expected, the experimental results were satisfactory. Significant differences between normal and abnormal gait were observed with p < 0.01. These results validated the use of these methods to simulate abnormal gait on a healthy individual. They also demonstrated the viability of this system for future clinical applications

Real-time wireless ambulatory gait monitoring system incorporating online periodical gait evaluations

Human gait analysis studies the coordination of human lower extremity in providing propulsion to move forward while maintaining the body balance, with one foot in contact with the ground at all time. Hence, gait analysis plays an important role in clinical settings and rehabilitations. It is widely performed to identify various gait disorders, to assess the functional performance of a patient’s lower limb before and after a surgery or medical treatment, and to evaluate patient’s rehabilitation progress. In engineering, its importance is reflected in the design and development of the prosthetic limb, Functional Electrical Stimulation (FES) system as well as the humanoid robot. Optical motion capture system and force platform are commonly used in gait analysis to quantify human motion. However, these systems are expensive, bulky and can only capture human motion in a dedicated environment i.e. laboratory. As an alternative, this thesis developed a real-time gait monitoring system that utilizes wireless miniature gyroscopes. The miniature gyroscope is small, light-weight, and can capture human motion in both indoor and outdoor environments. More importantly, it is equipped with wireless data transmission, which offers additional benefits. Wireless gyroscope provides relatively larger movement area. It also does not obstruct the natural motion of human lower extremity. Apart from the advantages offered by the wireless gyroscopes, this system also uses several novel methods to assist clinicians and researchers in identifying abnormal gait. These methods evaluate three main aspects of human gait. They are referred as the gait normality test, gait asymmetry analysis, and the estimation of gait dynamic stability. Gait normality test examines a person’s gait relative to normal/healthy individual’s gait that was established by other researchers. Gait asymmetry analysis is an evaluation that examines the bilateral differences between the left and right limbs.The estimation of gait dynamic stability determines human walking stability using nonlinear time series analysis. It uses short-term and long-term maximum Lyapunov exponent to quantify the ability of human neuromuscular locomotor system in maintaining body balance during walking. Experimental study was also conducted to examine the overall capability of this system. This study simulated the abnormal gait by placing a load on one side of the limbs and by wearing a sandal on one foot. These methods successfully altered the inertial property of a person’s lower limb, hence inducing significant differences in spatio-temporal gait parameters between the affected limb and the non-affected limb. As expected, the experimental results were satisfactory. Significant differences between normal and abnormal gait were observed with p < 0.01. These results validated the use of these methods to simulate abnormal gait on a healthy individual. They also demonstrated the viability of this system for future clinical applications