Effect of water to cement ratio and replacement percentage of recycled concrete aggregate on the concrete strength

Fine Recycled Concrete Aggregate (FRCA) is one of the construction waste can be recycled. It can be the aggregate to replace the natural aggregate in concrete since we know the physical properties of materials are hard and strong. Demand for sand in the concrete production has been increased which become the problems in the concrete industry. This work deals with the effect of concrete incorporating with FRCA as partial replacement of sand. The percentage of natural sand replaced by the FRCA was 0%, 15%, 20%, 25%, 30%, 45% and 60%. Other than that, water cement ratio was manipulated variable started form 0.40, 0.45, 0.50, 0.55 and 0.60. In short, 20% replacement was the most suitable interaction of FRCA in the concrete occur that contribute to increasing in compressive strength. The porosity properties of FRCA been neutralized on that replacement percentage by the present of optimum filler effect generated form the very fine FRCA particle during the mixing process. Meanwhile, 0.50 water cement ratio was optimum condition for cement hydration process using FRCA as partial sand replacement

Model Prediksi Kecelakaan Yang Melibatkan Pengguna Sepeda Di Kota Malang Dan Kota Blitar

Perkembangan teknologi yang tinggi di zaman modernisasi ini menuntut adanya perkembangan transportasi yang mumpuni. Namun ketidaksempurnaan hubungan dengan pertumbuhan penduduk menyebabkan timbulnya masalah yakni kecelakaan lalu lintas. Kecelakaan lalu lintas merupakan suatu keadaan yang melibatkan segala jenis kendaraan termasuk sepeda. Penelitian ini membahas tentang karakteristik pengguna sepeda; karakteristik jalan berupa fungsi jalan,,lebar jalan,jumlah lajur,lebar bahu jalan; serta karakteristik kecelakaan berupa jumlah dan kondisi korban, lokasi kejadian, dan jenis kecelakaan.Metode analisis yang digunakan pada penelitian ini adalah analisis deskriptif frekuensi dan Generalized Linier Model. Data diperoleh menggunakan survei volume lalu lintas,survei kecepatan, pengukuran geometrik dan dari badan-badan pemerintah terkait. Dari penelitian ini dapat disimpulkan bahwa di Kota Malang dan Kota Blitar pengguna sepeda yang sering terlibat kecelakaan berjenis kelamin laki-laki dan berusia diatas 55 tahun. Untuk karakteristik geometrik di Kota Malang adalah lebar lajur 2-4.7 meter, jumlah lajur 2-4 buah, lebar bahu 0-2.5 meter, kecepatan 41.5-55.8 km.jam dan Arus lalu lintas 611-5578 smp/jam. Sedangkan karakteristik Kota Blitar adalah lebar lajur 2-4,7 meter, jumlah lajur 2 buah, lebar bahu antara 0,5-2,3 meter, kecepatan 43,12-54,3 km/jam dan arus lalu lintas 65-1245 smp/jam. Model prediksi kecelakaan di Kota Malang yang dihasilkan kurang akurat, berikut merupakan modelnya BA=1.61x10-1 FLOW0.279 EXP(-0.312 SW). Model prediksi kecelakaan di Kota Blitar yang dihasilkan kurang akurat, berikut model tersebut ditampilkan BA=3.68x10-1 FLOW0.21

Dual-Band Bandpass Filter with Dumbbell Shaped Defective Ground Structure

A dumbbell shaped defective ground structure (DGS) is implemented to improve the performance of an existing dual-band bandpass filter topology. The filter design is based on parallel-coupled lines connected to matched transmission lines. Various positions and dimensions of dumbbell DGSs are implemented and their effects on the filter performance are investigated. It is found that the utilisation of dumbbell shaped DGSs in this topology improve the steepness of the responses for the first and second passbands with centre frequencies of 1.365 and 2.932 GHz respectively. The optimised dimensions of the DGS are 5 x 5 mm2 for both its rectangular slots connected by a 0.5 mm narrow slot width. The optimised positions of the DGSs are located at the centre and the edges of the parallel-coupled lines. The simulated and measured results of the filter are analysed and discussed in this paper

Indoor Radon Concentration in Dwellings of Baghdad City and In Dora Refinery Using Rad-7 Detector

Indoor radon gas (222Rn) has been recognized as one of the health hazards for human. Rn-222 is the most important source of natural radiation and is responsible for approximately half of the received dose from all sources. Most of this dose is from inhalation of the Rn-222 progeny, especially in closed atmospheres. Air radon comes mainly from soil and construction materials. Radon concentration was measured in two room of   9 dwellings from various regions of Baghdad city and in Dora Refinery, electronic detector of radon Rad-7 was used which is an active measurement method. The results show that Radon concentrations of the dwellings were varied from (0) Bq m-3 to (82.6) Bq m-3 with an average activity value of (22.75) Bq m-3.  The results show that radon concentration was high in sample B4 and low in samples B2,B5, B6 ,B8, .and for Dora Refinery the high concentration was (71.3 ) Bq m-3 in sample D11 and low was (0) Bq m-3 in samples D1,D2,D4,D5,D6,D7 and D8 an average activity value 19.2 Bq m-3 . the annual effective dose ranged between ( 0-3.3) mSv/y, with a mean value 0.4 mSv/y for Baghdad city and ranged between (0-2.8) mSv/y with a mean value 0.4 mSv/y for Dora Refinery . These results are lower than the value 1 mSv/y recommended by ICRP report. Keywords: Radon, RAD-7, Baghdad city, Dora Refinery, Annual effective dose

Lessons learnt of the COVID-19 contact tracing strategy in Islamabad Capital Territory, Pakistan using systems thinking processes

The strategy of test, trace and isolate has been promoted and seen as a crucial tool in the fight against the COVID-19 pandemic. As simple as the slogan sounds, effectively implementing it turns into a complex endeavor with multiple moving parts and the need for multisector collaboration. In this study, we apply a systems thinking lens to analyse the design and implementation of the contact tracing strategy for COVID-19 in the district of Islamabad, Pakistan. The data collection included participatory observation, reflective exercises, key informant interviews and participatory workshops with district health managers and health providers. The information gathered was structured using process and stakeholder mapping to identify the lessons learned of the COVID-19 contact tracing strategy. The results showed that the elements crucial for implementation were, good coordination during a crisis, available resources mobilized effectively and establishment of early active surveillance for contact tracing. Furthermore, the main aspects to be improved were lack of preparedness and existing surveillance systems and task shifting leading to impact on regular health services. The results of this study highlight the importance of developing information systems that are coherent with existing processes and resources, even in times of crisis

Non-visualization of lung markings below hemidiaphragm in subtle subpulmonic effusion: an old sign resuscitated

To assess the lack of visibility of vascular markings under the hemidiaphragm on a frontal chest radiograph as a sign of pleural effusion, fifteen patients were collected showing this sign. Pleural effusion was diagnosed by ultrasound, comparison with previous or subsequent chest x-ray or computed tomography. Patients in the study group exhibited this sign in the absence of the classical signs of pleural effusion. In the control group, lack of visibility of blood vessels was observed in only 4.2% cases. Non-visualization of vascular markings below the hemidiaphragm should alert the interpreter to the possible presence of pleural effusion and a lateral or decubitus view or ultrasound examination may be carried out to rule out effusion

Prevalence of Muscle Dysmorphia and Associated Health Activities in Male Medical Students in Karachi, Pakistan

Background: Muscle Dysmorphia (MD) is a subtype of body dysmorphic disorder (BDD) and is currently classified under anxiety disorders (subheading: Obsessive-compulsive disorder) in DSM 5. MD is hypothesized to affect the self-esteem and social outlook of the younger generation. MD shows a higher rate in males and may influence their self-confidence rendering them more prone towards using steroids, supplementary proteins and other drugs to alter their physical outlooks as shown in previous studies. This problem has been on the rise lately due to revolutionary advancement in the media and film industry and the abrupt changes about the standards of physical good looks and body shapes. With the lack of studies done in our population, our study will be helpful to consider the prevalence of the disease in our setting and increase awareness in the general public and clinicians. We hope to help clinicians/ therapists find better options in managing the disease. Materials: We performed a cross-sectional study with a sample size of 246 medical school students in Karachi to collect data through self-administered questionnaires. We used the DSM 5 criteria for the diagnosis of BDD and additional questions on the presence of MD. Nutritional habits, exercise routines, use of supplements and drugs were also obtained for exploratory analysis. Results: Our study predicted the prevalence of MD to be 25%. Other main findings included statistical significant associations between MD and the thoughts and practice of steroid use for muscularity. Conclusion: MD is an underdiagnosed and often unrecognized disease that we believe has significant consequences for the young male population. Further work is needed on this in our part of the world. Our research, we believe, can be a stepping stone for further studies that would incorporate wider populations