Article Per Year (5 Year)
p-Index From 2021 - 2026
0.659
P-Index
This Author published in this journals
All Journal Agromet Indonesian Journal of Agricultural Science Jurnal Matematika & Sains Jurnal Tataloka Jurnal Sains Dirgantara JURNAL METEOROLOGI DAN GEOFISIKA Jurnal Tanah dan Iklim Jurnal Meteorologi dan Geofisika
Tri Wahyu Hadi
Graduate Program Of Earth Sciences, Faculty Of Earth Sciences And Technology, Institut Teknologi Bandung, Bandung, Indonesia
Agriculture, Biological Sciences & Forestry Civil Engineering, Building, Construction & Architecture Earth & Planetary Sciences Education Energy Mathematics Physics

Published : 19 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 19 Documents
Search

 1   2 
Downward Propagating Equatorial Kelvin Wave over the Eastern Indian Ocean as Revealed from Radiosonde and GPS Radio Occultation (CHAMP) Data Noersomadi Noersomadi; Tri Wahyu Hadi
Jurnal Matematika & Sains Vol 15, No 1 (2010)
Publisher : Institut Teknologi Bandung

Show Abstract | Download Original | Original Source | Check in Google Scholar

Abstract

Vertical propagation of equatorial Kelvin wave and its correlation with convective activity over the eastern Indian Ocean were investigated through analyses and inter-comparisons of radiosonde and GPS/CHAMP occultation data. The radiosonde data from 80 balloon launchings were obtained in the period of August 5 to 14, 2005 over the region of 1.640 N - 6.20 S, 88.20 E- 97.340 E surrounding the cruise track of R/V Mirai during Tropical Ocean and Climate Study (TOCS) campaigned. Results of radiosonde data analyses show a variation in the height of cold point tropopause (CPT) associated with Kelvin wave activities. In addition, coexisting strong convective activities were also detected during August 9 to 11, 2005.  The characteristics of equatorial Kelvin wave were further investigated by fitting a sinusoidal approximation by assuming zonal wave number 1 and 2 to the GPS/CHAMP temperature perturbations using non linear inversion algorithm. It is found that the periodicity of observed Kelvin wave is about 5 - 6 days. Inter-comparisons of low-pass filtered of height-time cross section of perturbation temperature from both radiosonde and GPS/CHAMP data showed downward propagation Kelvin wave, which was more pronounced during August 11 to 14, 2005. Furthermore, an increase in the potential and kinetic energy of the downward propagating Kelvin wave was observed prior to the occurrence of strong convection, which is believed as convectively coupled equatorial Kelvin wave.
PENENTUAN NILAI AMBANG CURAH HUJAN UNTUK DETEKSI DINI KEKERINGAN PADA TANAMAN PADI SAWAH: STUDI KASUS PROVINSI JAWA BARAT DAN SULAWESI SELATAN Surmaini, Elza; Hadi, Tri Wahyu; Subagyono, Kasdi; Puspito, Nanang Tyasbudi
Jurnal Tanah dan Iklim (Indonesian Soil and Climate Journal) Vol 38, No 2 (2014)
Publisher : Balai Besar Penelitian dan Pengembangan Sumberdaya Lahan Pertanian

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21082/jti.v38n2.2014.79-87

Abstract

Abstrak. Defisit curah hujan dalam periode tertentu merupakan faktor dominan yang menentukan kekeringan agronomis. Oleh karena itu, nilai ambang curah hujan sebelum waktu tanam yang berpotensi menyebabkan kekeringan perlu diketahui untuk deteksi dini. Penelitian ini bertujuan untuk mengkonfirmasi bahwa penurunan curah hujan menyebabkan kekeringan agronomis pada tanaman padi sawah dan menentukan nilai ambang curah hujan yang berpotensi menyebabkan pada musim kemarau. Nilai ambang curah hujan dianalisis secara statistik menggunakan persamaan regresi polinomial antara Indeks Dampak Kekeringan Padi (IDKP) dengan curah hujan dan debit sungai. Model GR4J digunakan untuk menentukan korelasi antara curah hujan dan debit serta mensimulasi debit sungai pada tahun-tahun El Niño. Hasil analisis menunjukkan bahwa curah hujan cukup akurat digunakan sebagai indikator untuk deteksi dini kekeringan agronomis tanaman padi pada sawah tadah hujan dan sawah irigasi. Nilai ambang curah hujan pada sawah tadah hujan adalah 60-70 mm, sedangkan untuk sawah irigasi adalah 20 mm. Abstract. Prolonged deficit of rainfall is a dominant factor affecting drought severity. Therefore, rainfall threshold prior to planting time that potentially lead to agronomic drought need to be identified for early detection purpose. This research aimed to confirm the adequacy of rainfall for measuring drought on paddy rice, and to assess rainfall thresholds as indicator of drought on paddy rice during dry season planting. Rainfall thresholds were statistically analyzed using a polynomial regression between Paddy Drought Impact Index (PDII) and rainfall and river discharge. GR4J model was used to assess correlation between rainfall and river discharge and to simulate river discharge in El Niño years. We deduce that rainfall is an appropriate indicator for early detection agronomic drought for both rainfed and irrigated paddy rice. We also emphasize that the drought events should be predicted by rainfall thresholds whose values are 20 mm for irrigated paddy field and between 60 mm to 70 mm in rainfed paddy field.
ANALISIS VARIASI GEOGRAFIS POLA HUJAN DI WILAYAH PAPUA Rouw, Aser; Hadi, Tri Wahyu; H.K., Bayong Tjasyono; Hadi, Safwan
Jurnal Tanah dan Iklim (Indonesian Soil and Climate Journal) Vol 38, No 1 (2014)
Publisher : Balai Besar Penelitian dan Pengembangan Sumberdaya Lahan Pertanian

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21082/jti.v38n1.2014.25-34

Abstract

Abstrak. Studi ini menekankan pada sejauh mana aspek variasi geografis pola hujan di wilayah Papua berdasarkan terminologi pola hujan monsunal (A), ekuatorial (B), dan lokal (C) yang telah dikaji secara saintifik dan digunakan dalam operasional prakiraan musim di Indonesia. Analisis dilakukan pada data rata-rata curah hujan bulanan dari 362 stasiun penakar hujan di seluruh wilayah Papua mulai dari tahun 1901-2010 dengan panjang pengamatan 5-100 tahun menggunakan analisis PCA, cluster dan analisis spasial. Ditemukan 21 cluster variasi pola hujan di wilayah Papua, yaitu: (i) pola monsunal A dengan variasi pola, A1, A2, A3, A4, A5, dan A6, (ii) pola hujan ekuatorial B dengan variasi B1, B2, B3, B4, B5, B6, B7, B8, B9, dan B10, serta (iii) pola hujan lokal C dengan variasi C1 dan C2. Secara geografis pola hujan tersebut bervariasi menurut tiga area geografis utama, yaitu 7 cluster pola hujan: A2, A3, A4, A5 B6, B7, dan B8 di dataran rendah utara; 5 cluster pola hujan: A1, B3, B4, B5, dan B9 di deretan pegunungan tengah; dan 9 cluster pola hujan: A, A6, B, B1, B2, B10, C, C1, dan C2 di dataran rendah selatan Papua. Temuan pola hujan berimplikasi pada dua hal pokok dari sektor pertanian di wilayah Papua, yaitu pewilayahan komoditas pertanian, dan strategi budidya pertanian dengan mempertimbangkan keadaan klimatologis pola hujan serta variabilitas temporalnya. Abstract. This study emphasizes on the variation aspects of the geographical rainfall patterns in the Papua region based on the terminology of the A, B, and C rainfall patterns in Indonesian archipelago that have been scientifically assessed and used in seasonal forecasting in Indonesian. Analyses were performed on an average monthly rainfall of 362 rain gauges with the distributed observation length of 5 to 100 years (from 1901 to 2010) using PCA, cluster, and spatial analyses. It was found that there were 21 clusters of rainfall patterns in the Papua region Variation patterns of the monsoon A rainfall: A1, A2, A3, A4, A5, and A6; the equatorial rainfall pattern B: B1, B2, B3, B4, B5, B6, B7, B8, B9, and B10, and the local rainfall patterns C: C1 and C2. Geographically, the rainfall patterns vary according to three main areas, namely seven clusters in the northern lowlands: A2, A3, A4, A5 B6, B7, and B8; 5 clusters in the central mountain range: A1, B3, B4, B5, and B9; and 9 clusters in the southern lowlands: A, A6, B, B1, B2, B10, C, C1, and C2. The findings of the rainfall patterns have implications for two major issues of the agricultural sector, viz.,, zoning of agricultural commodities, and planting strategy by considering the state of climatological rainfall patterns and its temporal variabilities.
Analysis of Synoptic Disturbance in Maritim Continent Using Spherical Harmonics Transformation Method Sayful Amri; Faiz Rohman Fajary; Tri Wahyu Hadi
Agromet Vol. 34 No. 2 (2020): DECEMBER 2020
Publisher : PERHIMPI (Indonesian Association of Agricultural Meteorology)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29244/j.agromet.34.2.89-99

Abstract

This study aims to modify the idea of ​​WK99-analyzing the existence of signature in wave-number and frequency spectrum when the analyzed Outgoing Longwave Radiation (OLR) data is associated with a unique phenomenon in Maritime Continent (MC), Borneo vortex (BV). Although BV is often related to easterly equatorial wave disturbances, there was no specific study to examine its behavior in the spectral domain. The purpose of this study is to develop a method to diagnose certain signatures of BV through spectrum analysis of OLR data when BV occurs. In contrast to previous studies, to present the unique phenomenon in MC as a target for diagnostics, spectrum analysis is performed by Spherical Harmonics (SH). The results of the OLR data spectrum comparison when BV occurs with the OLR data spectrum when BV does not occur that in the anti-symmetrical component when BV occurs, the tropical depression-mixed Rossby gravity (TD-MRG) wave spectrum is stronger, especially in zonal wave-numbers 5 to 10 and frequencies 0.12 to 0.2. Similar to the anti-symmetrical component, the TD-MRG spectrum of the symmetrical component is also stronger at zonal wave-numbers 5 to 10 and frequencies 0.12 to 0.2. Moreover, the westward-propagating inertio-gravity (WIG) wave spectrum in the symmetrical component is also stronger at the time of BV than when there is no BV, especially at zonal wave-numbers 7 to 13 and frequencies 0.38 to 0.5. It can be concluded that when BV occurs, equatorial waves that propagate to the west, especially the types of TD-MRG and WIG waves are stronger than when BV did not occur. The results of durational grouped spectrum analysis of OLR data when BV occurs indicate that the longer the duration of BV occurs, the stronger the spectrum of TD-MRG and WIG wave types gets.
PREDICTION OF DROUGHT IMPACT ON RICE PADDIES IN WEST JAVA USING ANALOGUE DOWNSCALING METHOD Elza Surmaini; Tri Wahyu Hadi; Kasdi Subagyono; Nanang Tyasbudi Puspito
Indonesian Journal of Agricultural Science Vol 16, No 1 (2015): April 2015
Publisher : Indonesian Agency for Agricultural Research and Development

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21082/ijas.v16n1.2015.p21-30

Abstract

Indonesia consistently experiences dry climatic conditions and droughts during El Niño, with significant consequences for rice production. To mitigate the impacts of such droughts, robust, simple and timely rainfall forecast is critically important for predicting drought prior to planting time over rice growing areas in Indonesia. The main objective of this study was to predict drought in rice growing areas using ensemble seasonal prediction. The skill of National Oceanic and Atmospheric Administration’s (NOAA’s) seasonal prediction model Climate Forecast System version 2 (CFSv2) for predicting rice drought in West Java was investigated in a series of hindcast experiments in 1989-2010. The Constructed Analogue (CA) method was employed to produce downscaled local rainfall prediction with stream function (y) and velocity potential (c) at 850 hPa as predictors and observed rainfall as predictant. We used forty two rain gauges in northern part of West Java in Indramayu, Cirebon, Sumedang and Majalengka Districts. To be able to quantify the uncertainties, a multi-window scheme for predictors was applied to obtain ensemble rainfall prediction. Drought events in dry season planting were predicted by rainfall thresholds. The skill of downscaled rainfall prediction was assessed using Relative Operating Characteristics (ROC) method. Results of the study showed that the skills of the probabilistic seasonal prediction for early detection of rice area drought were found to range from 62% to 82% with an improved lead time of 2-4 months. The lead time of 2-4 months provided sufficient time for practical policy makers, extension workers and farmers to cope with drought by preparing suitable farming practices and equipments.
POLA KERENTANAN PESISIR INDONESIA TERHADAP DAMPAK PERUBAHAN IKLIM SEBAGAI BASIS PERENCANAAN ADAPTASI Djoko Santoso Abi Suroso; Tri Wahyu Hadi; Hamzah Latief; Edi Riawan
TATALOKA Vol 13, No 2 (2011): Volume 13 Number 2, May 2011
Publisher : Diponegoro University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (982.369 KB) | DOI: 10.14710/tataloka.13.2.108-118

Abstract

Most part of Indonesian coastal areas are vulnerable to inundation potential due to global sea level rise. This inundation is predicted to cause permanent flood and worsen abrasion along coastal zone where many populations live, also will threaten impor-tant infrastructures and economic assets, as well as well known tourism areas. To anticipate these various harming potential impacts, planning of adaptation to climate change is needed. In order to achieve the appropriate and effective adaptation planning, coastalvulnerability pattern needs to be recognized first, so that to suit the region’s characteristics. To recognize this coastal vulnerability pattern, certain similar characteristics need to be found represented by a group of indicators. Therefore, a method of analysis which is able to classify information into a certain group based on several similar characteristics is needed, that is so called as cluster method. By using cluster method and through iterative experiments, this study has succeeded in identifying coastal vulnerability patterns to inundation caused by global sea level rise. The experiments concluded that there are five indicators which clearly control the coastal vulnerability pattern; they are inundation area, infrastructures, population density, built area, and non-settlement area. This study also concludes that of the 325 districts/cities on Indonesian coastal, they can be classified into six patterns of vulnerability. Twenty three districts/cities among them (7.07%) are classified as highly vulnerable cluster, which generally characterized as high inunda-tion ratio value, high infrastructures value, high population density value, high settlement areas value, and low non-settlement areas value. Thus, several adaptation options consist of population control, revision of coastal spatial plans, and adjustment of infra-structures.
ANALISIS DATA BLR DAN EAR DALAM MENGKAJI FENOMENA MJO DAN KETERKAITANNYA DENGAN CURAH HUJAN DI ATAS KOTOTABANG DAN SEKITARNYA Eddy Hermawan; Arief Suryantoro; Mega Puspawardhany; Tri Wahyu Hadi; Udjianna S. Pasaribu; Findy Renggono
Jurnal Sains Dirgantara Vol 4, No.1 Desember (2006)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (637.24 KB)

Abstract

This paper is mainly concerned to the analysis of Madden Julian Oscillation (MJO) phenomena crossing over Kototabang, West Sumatere and surrounding areas using Boundary Layer Radar (BLR) and Equatorial Atmosphere Radar (EAR) data taken from September to December 2001 as cintinuing studied by Indriaty (2005). We are interested to continue, especially on the effect of MJO phenomena on the daily rainfall intensity distribution over Kototabang and surrounding area. We divided data into two steps analysis. First is the vertical profile analysi using BLR and EAR data, and the second step is surface analysis using RAINFALL INTENSITY DATA FROM TAKEN FROM THREE METEOROLOGICAL STATIONS IN wEST sUMATERA. tHEY ARE bADAN mETEOROLOGI DAN gEOFISIKA (bmg) Sicicin station (0.6˚LS; 100.22˚BT), BMG-Padangpanjang station (0.5˚LS; 100.41˚BT) and Statsiun Pengamat Dirgantara (SPD) LAPAN Kototabang (0.2˚LS; 100.32˚BT). The vertical profile of zonal-vertical wind vector of EAR data analysis shows that the pre-dominant wind mived to east direction, especially in surface layer, while in the upper troposhere the pre-dominant wind moved to the opposite direction, especially from September to December 2001. This result looks a siminar with the schematic theory of the MJO cross section along equator that described by Matthews (2000). A simiinar result is also shown by the BLR data analysis. Both EAR and BLR data are siminar each other. Since the MJO phenomena is expected passing over Kototabang around mid of November to mid of December 2001, we are interested to analysis the as already mentioned above using the global wavelet spectrum technique. The result shows that their pre-dominant peak ascillation is about 48 days. This result is consistent with the Outgoing Longwave Radiation (OLR) anomaly taken from infra-red sensor of satellite that already been done by Matthews (2000). While, the cross correlation function (CCF) analysis between zonal wind and rainfall data shows unsignificant (very small) value. We suspect that the surface rainfall intensity over Kototabang and surrounding area is not mainly dominanted by MJO phenomena.
VARIASI DIURNAL UAP AIR DI LAPISAN TROPOSFER BAWAH SAAT MADDEN JULIAN OSCILLATION FASE AKTIF MEMASUKI KAWASAN BARAT INDONESIA BERBASIS ANALISIS DATA GPS (DIURNAL VARIATION OF LOW LEVEL MOISTURE WHEN THE ACTIVE PHASE OF MADDEN JULIAN OSCILLATION ENTERING AREA OF WESTERN INDONESIA BASED ON GPS DATA ANALYSIS) Aries Kristianto; Tri Wahyu Hadi; Dudy Darmawan Wijaya
Jurnal Sains Dirgantara Vol 13, No 1 (2015)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1298.139 KB)

Abstract

Uap air di lapisan troposfer bawah (Low-level Moisture/LLM) berperan dalam pertumbuhan awan hujan. Teknologi Global Positioning System (GPS) mampu mengekstraksi uap air LLM dengan menerapkan metode kombinasi selisih uap air total hasil ekstrasi groundbased GPS dengan Precipitable Water Vapor (PWV) di lapisan troposfer atas ECMWF. Variasi diurnal LLM berbasis data GPS di beberapa kawasan yang ada di bagian barat Indonesia, yaitu wilayah Jawa bagian Barat dianalisis terutama saat fase aktif Madden Julian Oscillation (MJO) sebagai salah satu variabilitas dominan yang sangat penting di daerah tropis. Kejadian MJO November 2009 di wilayah Jawa bagian Barat memberikan dampak terhadap variasi harian LLM, dimana anomali hariannya meningkat seiring dengan menurunnya anomali OLR saat MJO onset, dan menurun saat pasca MJO. Di bagian utara menunjukkan konsentrasi LLM menurun dari barat-timur, sedangkan di bagian selatan konsentrasinya meningkat. Variasi dari utara-selatan menunjukkan konsentrasi LLM yang cenderung berubah-ubah, sementara di bagian timur peningkatan uap air ke arah selatan sesuai dengan analisis vektor angin. Variasi diurnal LLM November 2009 saat fase MJO aktif secara umum konsentrasinya lebih tinggi dibandingkan pra dan pasca MJO. Dari analisis indeks konvektif citra satelit MTSAT IR1 juga menunjukkan LLM saat MJO berkaitan dengan aktivitas konvektif, baik pada periode pra-MJO, saat onset, aktif hingga pasca MJO.Kata Kunci: LLM,GPS, MJO, OLR
PENGGUNAAN METODE ASPECT SENSITIVITY DALAM PENENTUAN TINGGI LAPISAN TROPOPAUSE DI SAAT MJO AKTIF MELINTAS KAWASAN KOTOTABANG DAN SEKITARNYA Eddy Hermawan; Irma Nurlela; Tri Wahyu Hadi
Jurnal Sains Dirgantara Vol 5, No.1 Desember (2007)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (447.882 KB)

Abstract

This paper is mainly concerned to the utilization of aspect sensitivity (Pv/Po) method to define the tropopause height variation over the equatorial Indonesia, nearby Kototabang (0,2˚S; 100,32˚E), Bukittinggi, West Sumatera using the Equatorial Atmosphere Radar (EAR), especially during the Coupling Processes Equatorial Atmosphere (CPEA) Campign I in 2004 is already done. It is very important to be done since the tropopause is the buffer layer between troposphere and stratosphere (and also contrary) that usually called as the Stratosphere-Troposphere Exchanged (STE) (Holton, 1996). Validation's results with the radiosonde data shows that (Pv/Po relatively higher that radiosonde data. They are about 712 meter and 961 meter for Cold Point Tropopause (CPT) and Lapse Rate Tropopause (LRT) version, respectively. The mean difference between CPT and LRT itself is about 248 meter. This is enough valid considering to the maximum difference between of them not more 500 meter ( Haynes and Shepherd, 2001). This result then be applied in determining of tropopause height variation over Kototabang especially when the Madden-Julian Oscillation (MJO) passed over this region from November to December 2001. It shown that there are no significant differences between MJO active and no active on the tropopause height determination about 17.98 km and 17.73 km, respectively. The most interest is the tropopause height variation is larger during the MJO active than non active.To get the better understanding of tropopause height variation, especially with good time and spatial height resolution, the utilization of ERA and other instruments Kototabang are very needed.
REANALISIS WEATHER RESEARCH AND FORECAST - FOUR DIMENSION DATA ASSIMILIATION (WRF-FDDA) UNTUK MENINGKATKAN AKURASI ESTIMASI POTENSI ENERGI ANGIN DI DAERAH LEPAS PANTAI (STUDI KASUS: PANTAI SELATAN JAWA BARAT) Nurry Widya Hesty; Tri Wahyu Hadi
Jurnal Sains Dirgantara Vol 13, No 1 (2015)
Publisher : Lembaga Penerbangan dan Antariksa Nasional

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (669.867 KB)

Abstract

Peta potensi energi angin lepas pantai yang akurat, memiliki resolusi tinggi, dan tidak tergantung pengukuran insitu sangat dibutuhkan untuk mengurangi biaya pengukuran langsung dan mendorong pengembangan teknologi Pembangkit Listrik Tenaga Angin di Indonesia. Dalam penelitian ini, dilakukan teknik asimilasi data nudging FDDA untuk memperbaiki akurasi model cuaca skala meso WRF di lepas pantai selatan Jawa Barat menggunakan data angin permukaan laut Cross-Calibrated Multi-Platform (CCMP) sebagai data asimilasi. Tes sensitifitas dilakukan dengan membandingkan enam buah parameterisasi Planetary Boundary Layer (PBL) terhadap sampel. Hasil uji menyatakan skema PBL Yonsei University (YSU) menjadi skema yang paling mendekati data stasiun pengamatan dan terpilih untuk dijalankan sepanjang 2008. Hasil model diverifikasi dengan data stasiun pengukuran di Sukabumi. Hasil verifikasi menunjukkan asimilasi data FDDA dapat mereduksi nilai RMSE dan menghasilkan pola distribusi angin mirip dengan data stasiun pengukuran.Kata kunci: WRF, FDDA, Potensi angin, Lepas pantai
Co-Authors Agus Safril Al Habib, Abdul Hamid Ardhasena Sopaheluwakan Arief Suryantoro Aries Kristianto Aser Rouw Bayong Tjasyono H. Kasih Djoko Santoso Abi Suroso Dudy Darmawan Wijaya Eddy Hermawan Eddy Hermawan Edi Riawan, Edi Elza Surmaini Elza Surmaini Elza Surmaini Elza Surmaini Faiz Rohman Fajary Findy Renggono Findy Renggono Giriharta, I Wayan Gita H.K., Bayong Tjasyono Hadi, Safwan Hamzah Latief Hutauruk, Rheinhart Hutauruk, Rheinhart C H Indra Gustari Indratno, Sapto Wahyu Irma Nurlela Kasdi Subagyono Kasdi Subagyono Lambok M. Hutasoit M. Ridho Syahputra Mega Puspawardhany Muharsyah, Robi Nanang T. Puspito Nanang Tyasbudi Puspito Noersomadi Noersomadi Nurry Widya Hesty Rahmanto, Edi Safwan Hadi Sayful Amri Subagyono, Kasdi Trilaksono, Nurjanna Joko Trinah Wati Udjianna S. Pasaribu Yoku, Priskila Wilhelmina Yolanda, Selvy