Yuni Rahmawati

In the six years from 2010 to 2015, the peak load in the East Java region increased by an average of 284MW per year. Karangkates Substation is part of an interconnected electrical system that supplies Java Island. To ensure a high level of reliability in its service, it is necessary to prepare for load growth to make sure that it does not exceed its ideal conditions, therefore special analysis of transformer capacity is needed. Using the Holt-Winters (HW) method as a reference for processing the data can be used as a reference in planning and anticipating the growing electricity demand. The results of this study are with the accuracy of the HW method with mean absolute percentage error (MAPE) = 2.645%, while the accuracy of the fuzzy time series (FTS) method = 6.399%. A forecast result done with HW methods shows the transformer at the substation Karangkates reached its normal working capacity in March 2018 at 99.583% of installed capacity and exceeded the maximum capacity in April 2018 at 101.493% of installed capacity.

Pelatihan Rancangan Evaluasi Pembelajaran Bagi Guru di Desa Sumbersuko Kecamatan Wagir Kabupaten Malang

In general, one of the main components used in electric power systems is a transformer. In principles, this equipment uses a magnetic process through the pairing winding where a cooling system is also applied to maintain the expected operational performance and to maintain heat transfer during the power delivery. In fact, load demand changes fluctuate depending on the behavior of energy users. This research is conducted to evaluate heat transfer in a three-phase transformer. This work also takes into the flowing current gradually based on the heat generated in the transformer. To cover these objectives, the analysis is directed to the power transformer optimization using the Artificial Salmon Tracking Algorithm (ASTA) for performing heat flow rates on-demand changes. The results obtained indicate that ASTA has a potential implementation for determining the optimal heat transfer. The demand changes have affected the power loss detected in both windings which are migrated out of heat through the cooling and fluid systems.

Recently, alternative energy becomes a popular issue associated with decreasing fossil energy source consumption. Moreover, this aim leads to renewable energy conservation for exploring potential sources, such as, solar and wind energy, which are more familiar than other energy sources. However, renewable energy usage is very dependent on the existing technology development which is applied to catch the natural energy sources. These works are subjected to study and estimate the downstream speed on the wind energy as a potential renewable energy source which is utilized for the wind farm energy harvesting. These works also consider the 24 hours operation based on technical parameters of the wind turbine and natural wind speed performances. These studies are demonstrated on the random surface roughness performing using an artificial salmon tracking algorithm. Results show that the random surface roughness influences the pattern of wind dispersion and wind speed reduction, as well as sweeping areas affected by the wind. It also has an impact on energy production related to the wind farm energy harvesting. Regarding the surface roughness within 0.01-0.936 randomly, the downstream speed covers 3.842-5.053 m/s. In particular, the wake decay also contributes to the wind sweeping in the harvesting potential energy area. By considering the hub high of 10 m, the highest downstream leads to the slowest speed on the constant wind flows.

Penelitian ini bertujuan untuk mengungkap signifikansi hubungan antara perilaku positif dalam praktikum (X1)dan keterlaksanaan bimbingan karir (X2)secara simultan terhadap kesiapan berkarir di dunia industri dan besar kontribusinya. Jumlah sampel sebanyak 157 siswa dengan menggunakan teknik simple random sampling. Pengambilan data menggunakan kuesioner tertutup yang telah memenuhi kriteria validitas dan reliabilitas. Teknik analisis data menggunakan analisis regresi ganda. Hasil dari penelitian ini adalah terdapat hubungan yang positif dan signifikan antara (X1) dan (X2) terhadap (Y) secara simultan dengan nilai psig < pstandart yaitu 0,000 < 0,05. Besarnya kontribusi (X1) dan (X2) terhadap (Y) sebesar 14,00% dengan persamaan garis regresi Y= 12,496 + 0,276X1 + 0,359X2.