Judul: Bowen Ratio and Evapotranspiration Dynamics: The Influence of Season and Diurnal Micrometeorological Variables
Abstrak: Tanaman membutuhkan air untuk mengoptimalkan proses biofisik dimana kebutuhan air dapat dikuantifikasi sebagai evapotranspirasi (ET). Rasio Bowen merupakan salah satu metode yang umum digunakan untuk praktik pertanian. Metode rasio Bowen digunakan untuk mengestimasi ET pada PTPN VI di Provinsi Jambi periode 2014-2015 menggunakan data observasi mikrometeorologi dan melihat pengaruh komponen mikrometeorologi seperti radiasi neto (Rnetto), fluks bahang (laten LE dan terasa H), tekanan uap aktual (ea), kelembaban tanah (SM), kecepatan angin (WS), suhu udara (Ta), fluks bahang tanah (G), dan LE-H terhadap pola harian dan diurnal. Hasil penelitian menunjukan bahwa pola harian rasio Bowen dipengaruhi secara kuat oleh LE-H, LE, H, SM ditunjukan dengan koefisien korelasi sebesar -0.85, -0.75, 0.84, -0.58. Pola diurnal rasio Bowen dipengaruhi oleh ea dengan koefisien korelasi sebesar -0.52 sedangankan pola harian ET dipengaruhi secara kuat oleh Rnetto, LE-H, H, rasio Bowen dengan koefisien korelasi sebesar 0.85, 0.95, -0.63, -0.75. WS, Ta, Rnetto, G, ea, RH dan LE-H mempengaruhi pola diurnal ET dengan korelasi sebesar 0.72, 0.72, 0.96, 0.89, 0.51, -0.64 dan 0.9. Nilai rasio Bowen yang konstan tidak akan akurat untuk menentukan ET karena perbedaan nilai maksimum rasio Bowen sebesar 10 kali lipat dari nilai minimum. Periode Desember 2014 – November 2015 menunjukan bahwa terdapat 7 bulan dimana curah hujan > ET (musim basah Desember 2014-April 2015, November 2015) dan 5 bulan dimana curah hujan < ET (musim kering May 2015-Oktober 2015). Kelapa sawit sangat rentan selama periode kering panjang ini yang disebabkan oleh fenomena El Nino kuat., Plant requires water to optimize its biophysical processes and this requirement can be quantified as evapotranspiration (ET). Bowen ratio is one method commonly used for agricultural practices. Bowen ratio method used to estimate ET from PTPN VI in Jambi province for the period 2014-2015 using observed micrometeorology data and looked at the strength of micrometeorological components in influencing the daily and diurnal patterns, which include net radiation (Rnetto), heat fluxes (latent LE and sensible H heat), actual vapour pressure (ea), soil moisture (SM), wind speed (WS), air temperature (Ta), ground heat fluxes (G), and LE-H. We found that the daily pattern of Bowen ratio was strongly influenced by LE-H, LE, H, SM shown by correlation coefficient of -0.85, - 0.75, 0.84, -0.58 respectively. Diurnal pattern of Bowen ratio was affected by ea with correlation coefficient of -0.52 while daily ET were strongly influence by Rnetto, LE-H, H, Bowen ratio with correlation coefficient of 0.85, 0.95, -0.63, - 0.75 respectively. WS, Ta, Rnetto, G, ea, RH and LE-H affected diurnal ET with correlation coefficient of 0.72, 0.72, 0.96, 0.89, 0.51, -0.64 and 0.9 respectively. Constant Bowen ratio value will not accurately estimate ET because maximum value is 10 times greater than minimum value. Within this period of 2014-2015 there were 7 months where rainfall > ET (wet period December 2014-April 2015, November 2015) and 5 months where rainfall < ET (dry period May 2015 - October 2015). During this long dry period of 2015, caused by strong El Nino events, oil palm become vulnerable to drought.
Keyword: Latent heat fluxes, Net radiation, Sensible heat fluxes, Temporal analysis  ET, Water requirement

Judul: Relationship Between Net Ecosystem Exchange (NEE) and Evapotranspiration (ET) in Oil Palm: Control of Water Availability and VPD on Water Use Efficiency (WUE)
Abstrak: Perkebunan kelapa sawit merupakan salah satu ekosistem terestrial yang berperan penting dalam siklus karbon global serta memiliki kemampuan menyerap karbon sekitar 76 ton CO2 per hektar per tahun. Fluks air dan karbon pada agroekosistem menjadi fokus dari studi hubungan pangan-energi-air. Penelitian ini dilakukan di PT Perkebunan Nusantara (PTPN) VI, Batanghari, Jambi dengan tujuan untuk menganalisis hubungan antara Net Ecosystem Exchange (NEE) dan evapotranspirasi (ET) di perkebunan kelapa sawit dalam rentang diurnal selama periode basah dan kering. Analisis menggunakan data periode basah bulan April 2015, Oktober 2017, dan Januari 2018 serta periode kering bulan Juli 2015, Agustus 2019, dan Juli 2020. Pengukuran dilakukan dengan menggunakan metode Eddy Covariance (EC) yang menghasilkan data Net Ecosystem Exchange (NEE) (µmol/m2/s) dan evapotranspirasi (ET) (mmol/m2/s). Hubungan antara Net Ecosystem Exchange (NEE) dan evapotranspirasi (ET) dianalisis dengan menggunakan koefisien determinasi (R^2) dan koefisien korelasi (r) dengan metode Pearson. Hasil penelitian menunjukkan adanya hubungan antara NEE dan ET selama periode basah dan kering yang berada pada kategori sangat kuat. Pada periode basah dan kering diurnal, koefisien determinasi (R^2) sebesar 0,958 dan 0,879, sedangkan koefisien korelasi (r) sebesar 0,979 dan 0,937. Adapun periode basah dan kering siang hari (R^2) sebesar 0,923 dan 0,810, sedangkan (r) sebesar 0,962 dan 0,9. Hubungan antara NEE dan ET kemudian dikaitkan dengan Water Use Efficiency (WUE) sebagai rasio antara NEE/ET (g CO2/kg H2O). Nilai WUE selama periode basah dan kering cenderung tinggi pada pagi hari dan menurun menjelang siang hari dengan rata-rata WUE periode basah yaitu 3,452 g CO2/kg H2O dan periode kering sebesar 3,361 g CO2/kg H2O. Selain itu, ditemukan bahwa WUE dapat menurun pada kondisi VPD yang tinggi. Kecenderungan terjadinya penurunan pada variabel yang dianalisis selama periode kering dan periode basah dikarenakan adanya perbedaan ketersediaan air., Oil palm plantations are one of the terrestrial ecosystems that play an important role in the global carbon cycle and can absorb carbon around 76 tons of CO2 per hectare per year. Water and carbon fluxes in agroecosystems are the focus of food-energy-water relationship studies. This study was conducted at PT Perkebunan Nusantara (PTPN) VI, Batanghari, Jambi, to analyze the relationship between Net Ecosystem Exchange (NEE) and evapotranspiration (ET) in oil palm plantations in a diurnal range during wet and dry periods. The analysis used data from the wet periods of April 2015, October 2017, and January 2018 and the dry periods of July 2015, August 2019, and July 2020. Measurements were made using the Eddy Covariance (EC) method, which produced Net Ecosystem Exchange (NEE) (µmol/m2/s) and evapotranspiration (ET) (mmol/m2/s) data. The relationship between Net Ecosystem Exchange (NEE) and evapotranspiration (ET) was analyzed using the coefficient of determination (R^2) and correlation coefficient (r) with the Pearson method. The results showed a relationship between NEE and ET during wet and dry periods which was in the very strong category. In diurnal wet and dry periods, the coefficient of determination (R^2) was 0.958 and 0.879, while the correlation coefficient (r) was 0.979 and 0.937. As for the diurnal wet and dry period, the coefficient of determination (R^2) is 0.923 and 0.810, while (r) is 0.962 and 0.9. The relationship
Keyword: evapotranspiration, net ecosystem exchange, palm oil, vapor pressure defici, water use efficiency

Judul: Grup dan Homomorfisma Grup pada Rubik Revenge
Abstrak: Rubik cube is a kind of puzzle game. A player must arrange rubik sides, which have been disordered, back to the position where every side has the same colour. This paper does not focus on the settlement solution, but instead on proving the existence of a group homomorphism between rubik movement group and S96 symmetric permutation group in rubik revenge. Firstly, it has been proved that rubik movement set is a group. Then, it also has been proved that the M set, which contains numeric labels of 1 until 96 in cubinos sides, is S96 symmetric permutation group.
Keyword: