Evaluasi Sistem Manajemen K3 Terhadap Metode Pemancangan Jack-in Pile

Pekerjaan Pekerjaan pondasi menggunakan metode jack-in pile sering kali menjadi pilihan pada proyek-proyek konstruksi di Surabaya. Meskipun lebih praktis dibandingkan metode lain, metode ini tetap menggunakan banyak alat berat sehingga kontraktor perlu memperhatikan penerapan peraturan untuk keselamatan para pekerjanya. Penelitian ini bertujuan untuk mengetahui apakah sistem manajemen K3 yang telah diterapkan oleh Perusahaan-Perusahaan kontraktor pemancangan sudah sesuai dengan peraturan yang ada atau tidak, serta mengetahui faktor-faktor yang memungkinkan terjadinya kecelakaan kerja. Dari hasil 2 metode penelitian yang dilakukan, didapatkan hasil yang cukup berbeda. Hasil wawancara tidak sesuai dengan hasil observasi di lapangan. Persentase penerapan yang mencapai 87,5% pada saat wawancara ternyata berbeda jauh dengan Kenyataannya yang hanya mencapai persentase 53,85%. Dari hasil ini dapat disimpulkan bahwa belum semua sistem manajemen K3 yang direncanakan oleh Perusahaan-Perusahaan kontraktor pemancangan diaplikasikan dengan baik di lapangan. Perusahaan tidak pernah menyediakan rambu-rambu K3 yang menyebabkan kesadaran yang rendah dari para pekerjanya untuk mentaati peraturan-peraturan, sebagai contoh, pekerja yang menggunakan helm hanya 38%, operator yang menggunakan pelindung kepala hanya 25%, kebersihan dan ketertiban di proyek masih sangat buruk

Pengaruh Kadar Semen Terhadap Soil Cement Column Pada Tanah Margomulyo - Surabaya

Aplikasi dari soil cement column untuk meningkatkan kekuatan tanah lunak menjadi tanah yang memiliki daya dukung yang tinggi diteliti dalam penelitian ini untuk mengetahui peningkatan kekuatan tanah lunak tersebut dengan waktu setelah dicampur dengan semen dengan kadar yang bervariasi dalam sebuah model test.12 kontainer berupa drum dengan diameter 46cm dan tinggi 80cm berisi tanah lunak Margomulyo digunakan dalam penelitian ini untuk membuat soil cement column. Bubuk semen, cement slurry, dan subtitusi bubuk semen dengan flyash sebanyak 15% digunakan dalam pembuatan soil cement colum berdiameter 300mm.Hasil penelitian menunjukan bahwa penambahan flyash sebanyak 15% terhadap penggunaan bubuk semen dengan kadar sama ternyata menunjukkan kekuatan campuran menjadi lebih tinggi yaitu 31 kg/cm2.Untuk campuran Semen slurry dengan kadar 35% menghasilkan kekuatan sebesar 33 kg/cm2 setelah 28 hari. Sedangkan,penggunaan bubuk semen dengan kadar 35% hanya menghasilkan kekuatan sebesar 18 kg/cm2

Anomalous Stability of nu=1 Bilayer Quantum Hall State

We have studied the fractional and integer quantum Hall (QH) effects in a high-mobility double-layer two-dimensional electron system. We have compared the "stability" of the QH state in balanced and unbalanced double quantum wells. The behavior of the n=1 QH state is found to be strikingly different from all others. It is anomalously stable, though all other states decay, as the electron density is made unbalanced between the two quantum wells. We interpret the peculiar features of the nu=1 state as the consequences of the interlayer quantum coherence developed spontaneously on the basis of the composite-boson picture.Comment: 5 pages, 6 figure

Grain size-dependent magnetic and electric properties in nanosized YMnO3 multiferroic ceramics

Magnetic and electric properties are investigated for the nanosized YMnO3 samples with different grain sizes (25 nm to 200 nm) synthesized by a modified Pechini method. It shows that magnetic and electric properties are strongly dependent on the grain size. The magnetic characterization indicates that with increasing grain size, the antiferromagnetic (AFM) transition temperature increases from 52 to 74 K. A corresponding shift of the dielectric anomaly is observed, indicating a strong correlation between the electric polarization and the magnetic ordering. Further analysis suggests that the rising of AFM transition temperature with increasing grain size should be from the structural origin, in which the strength of AFM interaction as well as the electrical polarization is dependent on the in-plane lattice parameters. Furthermore, among all samples, the sample with grain size of 95 nm is found to have the smallest leakage current density (< 1 μA/cm2)

Hypersensitive Response-Like Reaction Is Associated with Hybrid Necrosis in Interspecific Crosses between Tetraploid Wheat and Aegilops tauschii Coss

BACKGROUND: Hybrid speciation is classified into homoploid and polyploid based on ploidy level. Common wheat is an allohexaploid species that originated from a naturally occurring interploidy cross between tetraploid wheat and diploid wild wheat Aegilops tauschii Coss. Aegilops tauschii provides wide naturally occurring genetic variation. Sometimes its triploid hybrids with tetraploid wheat show the following four types of hybrid growth abnormalities: types II and III hybrid necrosis, hybrid chlorosis, and severe growth abortion. The growth abnormalities in the triploid hybrids could act as postzygotic hybridization barriers to prevent formation of hexaploid wheat. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report on the geographical and phylogenetic distribution of Ae. tauschii accessions inducing the hybrid growth abnormalities and showed that they are widely distributed across growth habitats in Ae. tauschii. Molecular and cytological characterization of the type III necrosis phenotype was performed. The hybrid abnormality causing accessions were widely distributed across growth habitats in Ae. tauschii. Transcriptome analysis showed that a number of defense-related genes such as pathogenesis-related genes were highly up-regulated in the type III necrosis lines. Transmission electron microscope observation revealed that cell death occurred accompanied by generation of reactive oxygen species in leaves undergoing type III necrosis. The reduction of photosynthetic activity occurred prior to the appearance of necrotic symptoms on the leaves exhibiting hybrid necrosis. CONCLUSIONS/SIGNIFICANCE: Taking these results together strongly suggests that an autoimmune response might be triggered by intergenomic incompatibility between the tetraploid wheat and Ae. tauschii genomes in type III necrosis, and that genetically programmed cell death could be regarded as a hypersensitive response-like cell death similar to that observed in Arabidopsis intraspecific and Nicotiana interspecific hybrids. Only Ae. tauschii accessions without such inhibiting factors could be candidates for the D-genome donor for the present hexaploid wheat

Stereotactic body radiotherapy for stage I lung cancer and small lung metastasis: evaluation of an immobilization system for suppression of respiratory tumor movement and preliminary results

<p>Abstract</p> <p>Background</p> <p>In stereotactic body radiotherapy (SBRT) for lung tumors, reducing tumor movement is necessary. In this study, we evaluated changes in tumor movement and percutaneous oxygen saturation (SpO₂) levels, and preliminary clinical results of SBRT using the BodyFIX immobilization system.</p> <p>Methods</p> <p>Between 2004 and 2006, 53 consecutive patients were treated for 55 lesions; 42 were stage I non-small cell lung cancer (NSCLC), 10 were metastatic lung cancers, and 3 were local recurrences of NSCLC. Tumor movement was measured with fluoroscopy under breath holding, free breathing on a couch, and free breathing in the BodyFIX system. SpO₂levels were measured with a finger pulseoximeter under each condition. The delivered dose was 44, 48 or 52 Gy, depending on tumor diameter, in 4 fractions over 10 or 11 days.</p> <p>Results</p> <p>By using the BodyFIX system, respiratory tumor movements were significantly reduced compared with the free-breathing condition in both craniocaudal and lateral directions, although the amplitude of reduction in the craniocaudal direction was 3 mm or more in only 27% of the patients. The average SpO₂did not decrease by using the system. At 3 years, the local control rate was 80% for all lesions. Overall survival was 76%, cause-specific survival was 92%, and local progression-free survival was 76% at 3 years in primary NSCLC patients. Grade 2 radiation pneumonitis developed in 7 patients.</p> <p>Conclusion</p> <p>Respiratory tumor movement was modestly suppressed by the BodyFIX system, while the SpO₂level did not decrease. It was considered a simple and effective method for SBRT of lung tumors. Preliminary results were encouraging.</p