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Pertumbuhan sektor pembinaan seperti pembinaan kemudahan infrastruktur, perumahan dan bangunan telah banyak memberi sumbangan kepada pertumbuhan ekonomi negara. Hasil daripada kerancakan pertumbuhan ini, keperluan terhadap guna tenaga di dalam memenuhi permintaan pembangunan menjadi semakin meningkat. Namun begitu, sektor pembinaan pada masa sekarang masih lagi bergantung kepada khidmat gunatenaga asing akibat kekurangan gunatenaga tempatan yang kurang berminat menyebabkan kehadiran buruh asing di tapak pembinaan boleh dikatakan sangat ketara. Malah, terdapat di sesetengah tapak pembinaan hampir 90 peratus daripada pekerjanya adalah buruh asing. Melihat kepada keadaan ini satu kajian telah dilakukan bagi mengkaji faktor-faktor penyebab buruh asing menjadi pilihan utama kontraktor berbanding dengan buruh tempatan. Kajian ini dibataskan kepada 21 buah syarikat kontraktor di negeri Pulau Pinang dan juga negeri Kedah bagi semua kelas iaitu kelas A hingga F. Data yang dikumpul melalui kaedah borang soal selidik dianalisis menggunakan perisian Microsoft Excel dan SPSS. Dapatan kajian mendapati 60.90 peratus daripada keseluruhan buruh di tapak bina adalah buruh asing. Manakala faktor-faktor buruh asing menjadi pilihan responden berbanding buruh tempatan adalah disebabkan faktor upah yang murah, kemahiran kerja yang tinggi, tahan lasak, sanggup bekerja lebih masa, disiplin kerja yang tinggi serta boleh bekerja di dalam kumpulan yang besar. Dapatan kajian terhadap ciri-ciri pilihan kontraktor dalam pemilihan buruh, bagi buruh asing ciri-ciri seperti upah yang rendah, pekerja lelaki berumur 18 tahun sehingga 40 tahun, ketahanan kerja, kerja lebih masa serta kemahiran yang tinggi menjadikan mereka sebagai pilihan utama responden berbanding dengan buruh tempatan.

Structural casing or conductor pipe provides a foundation for deepwater well and is designed to withstand the expected axial and bending loads. A very conservative design approach with worst case scenario is usually adopted for structural casing in exploration wells because the lack of information and high risk associated to deepwater operations cannot be underrated. This paper will present the evolution from a conservative to a fit-for-purpose engineering design approach. A design review with the latest interpretation of regional geological understanding derived from actual drilling experience was performed to quantify the associated uncertainties in the design phase. The result was compared with an independent analysis and validated during the actual installation performed by rig contractor. The project team supplemented this paper with a case study by sharing the conductor installation results from the jetting operation. In the early stage of deepwater exploration wells in Southeast Asia (SEA) region, many operators set their first string or structural /conductor pipe at around «80 m below mudline. This is a normal industry practice adopted from experiences in the GOM deepwater operation or operators' own experience in their deepwater field. This structural casing is generally jetted down with internal jetting BHA and drilled in riserless mode to the predetermined depth. This first string will not be cemented, and a subsequent surface casing will be installed and cemented to seabed. These two (2) strings will provide the foundation for a deepwater well to withstand the expected load, which are axial loads and bending loads. The conservative design generally uses a large size structural pipe like 36 in. OD with wall thickness from 1.5 in. to 2.0 in. WT. The second surface casing typically uses a large size pipe like 20 in. OD with moderate wall thickness. A weld-on connector are generally used for both structural and surface casings to accommodate the expected axial and bending load resulting from the installation of BOP and marine riser. The paper will describe the progression and transformation from the conservative to a fit-for-purpose design by optimizing the structural casing setting depth, its wall thickness and employing slim well architecture specifically for shallow well objectives below mudline. The most significant finding is that the slim design has proven to be suitable and was successfully installed in three (3) ultra- deepwater exploration wells in Brunei. This paper also will share the Company's experience and observation during the structural conductor installations to achieve efficient execution during jetting operations. The novelty of the fit-for-purpose design is in the ability to change the design norm resulting in substantial cost savings to the company and meeting the well objectives.

Voltage collapse event is identified as complex and localized in nature but its effect is extensive once occurred. The vital effect of voltage collapse would be the total system collapse or blackouts which would cost a large loss to utility companies. Eventually, on- line monitoring of power system stability has become an important factor for electric power utilities. The last utmost option to avert voltage collapse incident from occurring is by the implementation of under voltage load shedding scheme. The identification of location for load shedding is the main motivation of the study. The weakest bus in a power system is identified as the location for load shedding. This location is obtained using voltage stability index Ld. The performance and effectiveness of Ld index is compared with Fast Voltage Stability Index (FVSI) and Le Index. The results obtained indicate that Ld Index can be used to identify the weak bus in a power system and consequently for the placement of UVLS relays in a power system network.