Judul: Model Pertambahan Partisi Biomassa Tanaman Kedelai (Glycine Max (L.) Merrill)
Abstrak: Kedelai (Glycine max (L.) merill) merupakan tanaman dikotil yang termasuk kedalam kelas leguminosae. Model kedelai merupakan penyederhanaan sistem pertumbuhan dan perkembangan kedelai yang dapat digambarkan secara empiris dari penelitian langsung di lapang. Radiasi yang sampai di tanaman akan mempengaruhi suhu permukaan tanaman. Radiasi tersebut akan dikoreksi secara fisiologis dengan sudut daun dan kehijauan daun. Suhu permukaan daun akan mempengaruhi proporsi biomassa tanaman secara empiris. Berdasarkan hasil analisa secara empiris respon partisi biomassa terhadap suhu permukaan tidak spontan, terdapat jeda hari disetiap organnya. Respon suhu permukaan daun terhadap partisi akar memberikan jeda 22 hari dari awal tanam, batang 2 hari, daun 18 hari, dan polong 1 hari lebih cepat dari hari awal kemunculan polong. Fungsi partisi yang diperoleh digunakan untuk membangun model pertumbuhan dan perkembangan tanaman kedelai. Model yang dihasilkan nilainya berbeda dengan hasil observasi, sehingga memodelkan partisi biomassa dari suhu permukaan daun belum dapat dilakukan.
Keyword: kehijauan daun, proporsi biomassa, sudut daun, suhu permukaan daun

Judul: Pendugaan Pertumbuhan dalam Model Simulasi Kedelai (Glycine Max (L.) Merrill) dengan Pendekatan Neraca Energi
Abstrak: Radiasi matahari yang diintersepsi oleh daun akan dikonversi menjadi energi melalui neraca energi daun tanaman. Proses yang kompleks neraca energi daun tanaman dapat dimodelkan untuk memprediksi pertumbuhan biomassa. Energi intersepsi matahari terukur pada perlakuan N0% M0 rata - rata diatas 400 J/m2, dan perlakuan N50% M0 rata - rata dibawah 250 J/m2. Pertumbuhan biomassa pada 12 MST tanaman kedelai N0% M0 mempunyai berat 61 gram sedangkan N50% M0 mempunyai berat 36 gram. Neraca energi daun tanaman terdiri dari energi H (sensible heat flux) dan energi HL (latent heat flux). Nilai kedua energi tersebut didapat dari nilai β (Bowen ratio) yang mengambarkan rasio energi H dan HL. Semakin tinggi nilai β maka proporsi energi yang terkonversi untuk melakukan penguapan air (HL) oleh daun tanaman lebih besar dibandingkan dengan energi untuk memanaskan udara (H). Hubungan antara hasil model dan hasil observasi berdasarkan uji plot 1:1 pada perlakuan N0% M0 dan N50% M0 menghasilkan nilai koefisien determinasi 0.98 dan 0.94 pada setiap perlakuan. Hasil pengujian dengan uji t berpasangan antara hasil model dan hasil observasi pada perlakuan N0% M0 menunjukkan hasil yang tidak berbeda nyata (P>0.05) dengan P-Value 0.72, tetapi perlakuan N50% M0 menunjukkan hasil yang berbeda nyata (P<0.05) dengan P-Value 0.01.
Keyword: Bowen ratio, latent heat flux, sensible heat flux

Judul: Exchange Market Pressure and Central Bank Intervention for Three ASEAN Countries
Abstrak: Two of the exchange rate systems which are adopted by many countries are the floating and the fixed exchange rate system. Both the exchange rate systems have different characteristics. Countries that implement fixed exchange rates system tend to set their domestic currency exchange rate at a certain point. On the contrary, countries which implement floating exchange rate system tend to let their domestic currency exchange rate to move flexibly and thus their value will always change according to the demand and supply of the currency in the foreign exchange market. Countries which implement floating exchange rate system are facing the risk of fluctuation in the exchange rate of their domestic currency against foreign currencies. The currency exchange rate fluctuation may be caused by economic problems such as a financial crisis. A country can also be potentially affected by other countries’ earlier financial crisis. This effect could potentially happen if these countries are in the same region, such as ASEAN. The 1997 ASEAN economic crisis was an example of a country’s financial crisis could affect other countries. At that time, some countries such as Indonesia, Malaysia and Thailand had to change their currency exchange rate system from the fixed exchange rate system to the floating exchange rate system due to the high costs which has to be incurred if they were to enforce the fixed exchange rate system. During 2002 until 2012, the domestic exchange rate of Indonesia, Malaysia and Thailand against the U.S. dollar had tended to fluctuate. If the domestic currency exchange rate fluctuated excessively then the central bank would intervene to stabilize the exchange rate in the foreign exchange market. The pressure on domestic currency exchange rate pressures has forced the central bank to intervene. The amount of those pressures can be analyzed by calculating the Exchange Market Pressure (EMP) index. Apart from that, the time when interventions are done by the central bank can be known based on EMP by calculating the Exchange Market Intervention (EMI) index. The purposes of this study were to determine the level of international pressure on the currency exchange market and monetary authorities intervene in three ASEAN countries, as well as to determine the effect of the monetary authorities intervene on the exchange rate of the domestic currency against the U.S. dollar in those three ASEAN countries. Based on the EMP index calculation results which are obtained during 2002 to 2012 period, the exchange rate of Indonesia, Malaysia and Thailand’s domestic currency had always fluctuated and the results of the EMP index indicated that each country were under diverse level of currency exchange rate appreciation and depreciation pressures. Thailand was the country with the highest currency exchange rate pressure compared to Indonesia and Malaysia. The results on the intervention index calculation showed that Indonesia, Malaysia and Thailand have intervention index between zero and one and more than one. We can also see from the intervention index that Indonesia and Thailand implement the controlled floating currency exchange rate instead of the freely floating one. Based on the calculation of the currency exchange rate by comparing
Keyword: exchange rate, exchange market pressure, intervention