Judul: Analisis Beban Kerja dan Korelasinya terhadap Produktivitas Kerja pada Proses Produksi CPO di PMS Semuntai PTPN XIII Pasir, Kaltim.
Abstrak: The processing of fresh fruit bunch (FFB) into crude palm oil (CPO) is basically an oil extraction process which takes place in 8 processing stations,which are loading ramp, sterilizer, thresher, screw press, clarifying, kernel plant, boiler, and engine room. FFB processing activities in a palm oil mill with a capacity of 50 tones FFB hour-1go on 24 hours daily. The palm oil mill still uses men power as tool and engine operators which are arranged into night work and day work shifts. This mill has a dynamic working system so that there is a close relationship between technology as a machine and human as a labor. A relatively heavy work, noisy work environment, and hot temperature could result in a risk of exhaustion, work accident, and lowering work productivity. Analysis of workload through direct heart rate measurement of the operator when performing work on the station can provide the actual workload condition that occured. This study aims to analyze the level of workload and its correlation to work productivity in palm oil processing plant with a capacity of 50 tonnes FFB hour-1, as well as analyzing the number and distribution of optimal labor based on workload level, energy consumption and labor duration. This research was conducted at Semuntai Palm Oil Mill, which belongs to PT Perkebunan Nusantara XIII. The research activities carried out at 8 processing stations involving 18 operators. Heart rate analysis was conducted to determine operator’s workload level qualitatively and quantitatively using a Heart Rate Monitor. Heart rate measurement began with the step test calibration to determine the characteristics of the heart rate of each operator and was followed by measuring subject’s heart rate when performing work on each processing station. Workload level indicator (qualitative) was presented in the terminology of Increase Ratio of Heart Rate - IRHR (Syuaib 2002), while the rate of energy consumption (quantitative workload) was presented in the terminology of Total Energy Cost (TEC) in the unit of kcal per time. In addition to energy consumption we also measured labor productivity of operator for each day work and night work shift. Value of labor productivity could be seen from the TBS capacity that could be processed by each operator on his station and the effective time that needed to accomplish the job. Measurement of ambient condition of work environment on processing stations included noise levels, temperature, and humidity. The ambient condition of work environment showed that noise level at processing stations varied between 77.73 and 108.40 dB, with the highest level occuring at engine room. Work environment temperature at processing stations varied between 27.50 and 36.43 C, where the highest temperature also occured at engine room. Relative humidity at processing stations varied between 21.19 and 71.1 % where the highest level occured at clarifying station. The result showed that the level of workload in general was “light” to “moderate” with the Increase Ratio of Heart Rate (IRHR) value of 1.15 to 1.74. The highest workload level occured at boiler station with IRHR value of 1.74. The effective work time needed to accomplish the whole work target
Keyword: Palm oil mill, workload, FFB processing

Judul: Workload analysis and optimization of harvesting procedure at sari lembah subur oil palm Plantation, Riau
Abstrak: Nowdays, oil palm harvesting process is still done manually which led to many variations in quality of harvest, workburden or physical disorder. This study aimed to determine the rate of energy consumption, workburden level and recovery time so that the best procedure of harvesting can be obtanined based on the productivity and labor’s capacity. This research was conducted with heart rate analysis approach, the standard time of harvest and work productivity. This study was conducted at 8 harvesters that have been observed as subjects that grouped by age, variations in topography and the use of harvesting equipment. The result showed that the rate of energy consumption for subjects aged < 30 years was higher than subject aged > 30 years. Based on the topography, harvesting which is done in terraced area required energy consumption rate more than flat area. Based on the using of tools, harvesting which is done using “egrek” have energy consumption rate higher than “dodos”. Working in pairs can be the best alternative for harvesting oil palm in F-B-D, T-K-E and F-KE. At F-B-D condition harvesting activities is done by 2 people aged > 30 years old. Then, at T-K-E and F-K-E, harvesting is conducted by 3 harvesters that consisted of 1 person aged > 30 years for doing the first subsystem and 2 people aged < 30 years for doing the second subsystem.
Keyword: working procedure, palm oil, harvest, energy comsumption rate

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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