Development and Usability of the Specific Heat Capacity Application Kit Among Form 4 Students

This study aims to develop an application kit for the specific heat capacity subtopic of the topic of heat and assess the degree of usefulness of the application kit for specific heat capacity among form four students in Malaysia. This development design study based on constructivism theory uses the ADDIE model. A total of 36 Form 4 students were chosen as research participants using a simple random sample procedure to assess the usability level of the application kit. The study tool utilized is a 4-point Likert scale expert validity assessment form and a research question form on the usability of the Specific Heat Capacity Application Kit. The expert approval percentage approach is used to assess expert validity. The Cronbach Alpha reliability coefficient was calculated using the Statistical Package for the Social Sciences (SPSS) software, and the data for the usability study questions were analyzed using descriptive statistical analysis to determine the mean value and standard deviation. The study's findings revealed that the expert approval value for the application kit and instrument was high, with 95.5% and 97.5%, respectively. It received a high dependability rating of 0.82 for the research instrument. The findings also revealed that the application kit is entirely usable (M = 3.84, SP = 0.36). As a result, this application kit is appropriate for use as teaching and learning material for the Form 4 subtopic of specific heat capacity. This application kit will aid in the development of a more active and two-way learning environment between the learner and the instructor, as well as improve the learner's comprehension of the Specific Heat Capacity subtopic

One-Side-Electrode-Type Fluidic Sensing Mechanism Inspired from Fish Cupula

Penambahbaikan reka bentuk penderia berasaskan silikon direalisasikan dengan teknik fabrikasi kompleks yang mungkin mengurangkan keteguhan dan kebolehpercayaan penderia. Selain itu, kebanyakan penderia aliran semasa hanya mampu mengukur aliran dalam satu arah dan memerlukan lebih daripada satu penderia untuk meningkatkan keupayaan terutamanya untuk penderiaan pelbagai arah. Masalah-masalah ini boleh ditambah baik dengan menggunakan sistem bendalir untuk pengukuran aliran bawah air yang diinspirasikan daripada mekanisma kupula pada badan ikan. Kupula menjadi pengantara daya-daya seretan dalam suasana sekeliling dan memindahkan pergerakan kepada sel-sel rambut untuk mendorong isyarat sel saraf. Reka bentuk penderia aliran yang dicadangkan dalam kajian ini terdiri daripada elektrod-satu-sisi dan membran berbentuk kubah yang diintegrasi dengan saluran mikro. Apabila aliran mengenai membran, ia memberikan pesongan dan menganjak elektrolit di dalam saluran mikro. Elektrod, melalui lapisan penebat mengesan pergerakan elektrolit dan memberi perubahan dalam kemuatan. Dalam peringkat reka bentuk, simulasi telah dimulakan dengan memilih tiga jenis struktur termasuk bentuk segi empat tepat dan silinder sel rambut dan juga bentuk kubah. Struktur kubah didapati lebih sesuai untuk penderiaan pelbagai arah kerana struktur simetri yang membenarkan daya seretan yang tetap dari arah yang berbeza. Parameter membran berbentuk kubah seperti dimensi dan bahan-bahan telah diubah dan disimulasi. Disebabkan oleh mekanisma penderiaan baru, penderia tekanan yang mempunyai membran rata telah difabrikasi sebagai ujian awal. Kedua-dua membran berbentuk kubah dan membran rata telah difabrikasi menggunakan proses litografi lembut. Kemudian, penderia tekanan berasaskan bendalir telah dicirikan berdasarkan kesan getaran dan suhu. Ujian kebolehpercayaan penderia tekanan untuk getaran dan suhu telah menunjukkan ralat pengukuran penderia ialah 3% oleh getaran lebih 25 Hz pada pecutan ± 2G dan 4%, untuk julat suhu daripada 10 hingga 50oC. Untuk pencirian penderia aliran berasaskan bendalir, frekuensi operasi dan masa tindak balas masing-masing adalah 1.2 kHz dan 0.35 s. Penderia ini dapat mengukur kadar aliran serendah 10 cm/s di dalam air, dengan resolusi 5 cm/s. Ujian berarahan menunjukkan bahawa penderia itu mampu untuk mengesan aliran dalam pelbagai arah dan sudut yang berbeza, di samping dapat mengesan objek bergerak pada jarak dekat. ________________________________________________________________________________________________________________________ Enhancement of silicon-based sensor designs is often realized using complex fabrication techniques which may reduce the robustness and reliability of the sensor. Also, most current flow sensors are only capable of measuring in one direction, requiring more than one sensor to improve capability, especially for multidirectional sensing. These problems may be enhanced using a fluidic system for underwater flow measurement, as inspired from the cupula mechanism on fish bodies. A cupula mediates the drags forces in the surrounding environment and transfers the movements into hair cells to induce the neuron signals. The proposed flow sensor design in this research consists of a one-side-electrode and dome-shaped membrane integrated with a microchannel. When the flow hits the membrane, it provides deflection and displaces the electrolyte inside the microchannel. The electrode, via its insulator layer senses the movement of the electrolyte and gives a change in capacitance value. During the design stage, the simulation was started by selecting three types of structure, including rectangular and cylinder shape of hair cell and also the dome-shaped. The dome structure has been found to be more suitable for multidirectional sensing due to its symmetry structure, which allows the constant drag force from different directions. Dome-shaped membrane parameters such as dimension and materials were varied and simulated. Due to the new sensing mechanism, the pressure sensor that has flat membrane was fabricated as a preliminary test. Both a dome-shaped membrane and flat membrane were fabricated using the soft lithography process. Then, a fluidic based pressure sensor was characterized based on vibration and temperature effect. A reliability test for the pressure sensor for vibration and temperature has demonstrated that the sensor measurement error was 3% by vibration over 25 Hz at acceleration ±2G and 4%, for a temperature range from 10 to 50oC. For the fluidic based flow sensor characterization, operating frequency and time response were 1.2 kHz and 0.35 s, respectively. This sensor was able to measure the flow rate at rates as low as 10 cm/s in water, with a resolution of 5 cm/s. The directionality test has shown that the sensor is capable of detecting flow in different direction and angle, while also being able to detect a moving object at close range

Modeling and simulation of artificial hair cell sensor for underwater applications

This article uses finite volume and finite element methods for optimization of the artificial hair cell sensor. The performance of the sensor was investigated for different materials such as sicon and polysilicon and by varying hair cell dimensions including width and length. The silicon material which has low young modulus was proposed based on the simulation performance. The performance of the hair cell sensor was achieved by increasing the hair cell length while increasing the width did not significantly influence the performance. The performance of the sensor was studied for its viscous force, deflection, von mises stress and sensitivity. From the simulation, the hair cell with a length of 1600 μm and 80 μm width was suggested for the subsequent analysis. Another way to improve the performance was by modifying the hair cell geometry and it was proved that the modified hair cell was more sensitive, based on the deflection. The angle of flow that hit the hair cell also affected the deflection of the sensor where the zero angle flow which was parallel to the substrate was the most effective angle. The limitations of the performance of hair cell for various fluid velocity were also discussed in this paper

Analytical Analysis of Flexible Microfluidic Based Pressure Sensor Based on Triple-Channel Design

In designing a flexible microfluidic-based pressure sensor, the microchannel plays an important role in maximizing the sensor's performance. Similarly, the material used for the sensor's membrane is crucial in achieving optimal performance. This study presents an analytical analysis and FEA simulation of the membrane and microchannel of the flexible pressure sensor, aimed at optimizing it design and material selection. Different types of materials, including two commonly used polymers, Polyimide (PI) and Polydimethylsiloxane (PDMS) were evaluated. Moreover, different designs of the microchannel, including single-channel, double-channel, and triple-channel, were analyzed. The applied pressure, width of the microchannel, and length of the microchannel were varied to study the normalized resistance of the microchannel and maximize the performance of the pressure sensor. The results showed that the triple-channel design produced the highest normalized resistance. To achieve maximum performance, it is found that using a membrane with a large area facing the applied pressure was optimal in terms of dimensions. In conclusion, optimizing the microchannel and membrane design and material selection is crucial in improving the overall performance of flexible microfluidic-based pressure sensors

Performance experiment and numerical prediction of the copper based hair cell sensor for underwater sensing

This paper demonstrates the performance experiment and numerical prediction of the copper based hair cell for underwater sensing. Generally, the hair cell consists of the single cantilever that attached perpendicular to the substrate and integrated with strain gage (Kyowa type: KFG-1N-120-C1-11). The hair cell sensor was simulated using different flow rates to study the pressure and the strain distribution acting on the sensor by using computational fluid dynamic and finite element analysis approach. High performance sensor can be achieved by increasing the length of the hair cell and also using low Young Modulus material. The hair cell has been fabricated for dimension of 8000 μm length, 2000 μm width and 100 μm thickness, where the copper was chosen due to its mechanical properties. The response time for a sensor to respond completely to a change in input is about 50 m/s and the sensitivity in terms of output voltage and input flow rate is 0.2 mV/ms-1. Also, the result obtained in the simulation is aligned with the experimental result. The experiment for moving object detection proved that this sensor is able to detect the moving object and it is necessary for underwater applications, especially for monitoring and surveillance

Drag force acting on the biomimetic flow sensor based artificial hair cell using CFD simulation

980-986This paper demonstrates the modeling of the biomimetic flow sensor based artificial hair cell using computational fluid dynamic (CFD) approach. Velocity of fluid, length of hair cell and also the angle of flow to the hair cell were varied in order to study the hydrodynamic parameter such as velocity and the drag distribution. Dag force acting on the hair cells linearly increased as the flow velocity and the length of hair cell increased. Maximum drag for hair cell length was 8 mm which equaled to 7 mN/ms-1 based on the drag force and the fluid velocity. For different angle of flow, the drag force is at maximum when the flow was parallel with the substrate and approaching zero when the flow angle was perpendicular. To improve the hair cell, the dome-shaped structure was proposed and discussed for multi directional flow measurement