Judul: Termoregulatory response and shade occupation behaviour of dairy heifers PFH offered diet content
Abstrak: A research was conducted to study, the effect of energy diets and environmental conditions on termoregulatory and behaviour responses of dairy heifers. A 4 x 4 latin square design was used for data analysis using 4 dairy heifers and 4 treatments of feed energy for 21 days periods. The treatments were A (TDN : 55%), B (TDN : 60%), C (TDN : 65%), and D (TDN : 70%). All diets content 12 – 15 % of CP. Observed variables were environment factors (air temperature, relative humidty, THI, wind speed, and solar radiation) and termoregulatory responses (Tr, mTs, Tb, HR and RR), TDN intake, animal growth and their behaviour especially shade occupation. Data were analized by variance and/or regression analysis followed by the LSD for any significant difference among treatments. The results showed that TDN intake for A, B, C, D were 4.2, 4.3, 4.4 and 4.3 kg/d, respectively. There was no differences in body gain among treatments (P>0.05). The treatments significantly influenced the thermoregulatory responses (P<0.01). The D treatment resulted in more heat stress than that of the other treatments. Shade occupation showed significantly correlated to environtmental factors or TDN intake (P<0.01). It was concluded that the animals under 60-65% of TDN intake showed optimum growth rate without experiencing of severe heat stress; The combination of environmental conditions and higher feed energy intake increased heat load on dairy heifers.
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Judul: Upper critical temperature of Fries Holland heifers based on physiological responseses for feeding management using Artificial Neural Network simulation.
Abstrak: The management strategy was carried out by predicting the heifer critical temperature determination based on physiological response on feeding management trough ANN simulation. The purpose of this research was to determined the critical temperature for FH heifer based on physiological response with on different feeding time which was fed concentrate that contains different TDN. The objective of the present study is to evaluate physiological responses of dairy heifer to feeding time when fed concentrate differences in TDN content. Six dairy heifers were randomly allocated to 1 of 6 treatments: two feeding times (5 am/6 pm or 8 am/4 pm) of concentrate with 70 % or 75 % of concentrate unsupplemented or supplemented with 3.5 % coconut oil, in each of 6 periods of 14 d each in 6 x 6 Latin square design. The environmental conditions (air temperature, relatitive humidity, temperature humidity index, radiation, and wind velocity) and animals responses (rectal temperature, skin temperature, body temperature, heart rate, respiration rate, feed consumption, feed comsumption rate, chewing rate, and average daily gain) were then measured. The environmental condition were measured daily at 1 h intervals from 5 am to 8 pm. The animals responses were measured at the 4th, 8th, 12th, 14th, day of each periode at 1 h intervals from 5 am to 8pm, Tukey’s test and LSD were used for statististical analysis among treatments. The heifer critical temperature determination with physiological response indicator on feeding management was simulated by using Artificial Neural Networks (ANN) analysis. Artificial Neural Network (ANN) simulation for industrial engineering is used to define critical temperature of Fries Holland (FH) heifer based on physiological responses on models to predict rectal temperature, skin temperature, heart rate and respiratory rate, using ambient temperature and humidity inputs. The research was conducted using six dairy cattle in Bogor and Jakarta. The heifers were fed 6 am and 3 pm daily. The environmental condition (Ta, Rh, THI, and Va) and physiological responses (rectal temperature, skin temperature, heart rate, and respiration rate) were then measured for 14 days in two months at 1 h intervals started from 5 am to 8 pm. By using this ANN simulation. The critical temperature for FH heifer were defined, from rectal temperature at Ta 26 0C and Rh 86 % at Bogor, and at Ta 26 0C and Rh 88 % at Jakarta, from skin temperature at Ta 31 0C and Rh 86 % at Bogor, and at Ta 32.5 0C and Rh 88 % at Jakarta, from heart rate at Ta 24.5 0C and Rh 78 % at Bogor, and at Ta 23.5 0C and Rh 88 % in Jakarta, from respiratory rate at Ta 22.5 0C and Rh 78 % at Bogor, and Ta 23.5 0C and Rh 78 % at Jakarta. The result of this research was physiological response was lower in FH heifers which was fed at 05.00 am and 06.00 pm compared to the heifers which was fed at 08.00 am and 04.00 pm. The critical temperature on FH heifer was increased on heifers which was fed at 05.00 am and 06.00 pm
Keyword: ANN, coconut oil, feeding time, high critical temperature, physiological responses, coconut oil, TDN

Judul: Konstruksi aritmetika kurva eliptik F(2m) supersingular dan non-supersingular untuk skema kunci publik ElGamal
Abstrak: Algoritme ElGamal adalah salah satu algoritme kunci publik dengan aritmetik modular p yang mempunyai struktur grip siklik Z(p). Tingkat keanaman algoritme ini terletak pada pemecahan masalah logaritme diskret dari Z(p). Akan tetapi, tingkat keamanan tadi tahun ke tahun semakin menurun yang disebabkan kemampuan pemecahan algoritme diskret semakin meningkat. Untuk memenuhi tingkat keamanan yang memadai dibutuhkan p yang cukup besar yang menyebabkan proses enkripsi dan dekripsi menjadi lambat.
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