Returning...

Hi all,

First of all, I want to apologise that this blog was idle for over than five years from 2017.

It is very difficult to manage the blogging behaviour when you had a lot distractions (e.g, office tasks and dramas, family (particularly kids) matters, etc.

I unintentionally opened this blog again last week when I tried to create a WordPress account to start blogging again. While WordPress is awesome but it seems not free with some costs to publish it. So, I remembered this blog and try to open again...and this works...awesome...

So, from now I would try to consistently write something in this blog regularly as a side hobby. I think writing in a blog would be beneficial for us to keep maintain our writing skills.

All right, that is for the intro and see you...

Wellington, 09122024

Jalan Panjang menuju Australia

Dalam kesempatan yang baik ini saya ingin berbagi pengalaman pribadi selama berjuang dan menjadi pemburu beasiswa sampai akhirnya saat ini bisa kuliah di Curtin University, Perth, Western Australia tahun 2017. Sebelumnya sempat menjadi pertanyaan di benak kenapa harus kuliah ke luar negeri dan setelah berbincang dengan salah satu rekan senior di kantor yang pernah kuliah di Jepang, beliau berpendapat bahwa kuliah di luar negeri akan menambah pengalaman kita dan merubah cara pandang kita karena akan bergaul dengan teman – teman dari berbagai negara yang berbeda. 

Semua berawal di bulan November 2013 saat saya terpilih mewakili institusi tempat saya bekerja, Badan Pengkajian dan Penerapan Teknologi (BPPT) sebagai salah satu young scientist untuk mengikuti capacity building program tentang Earth and Ocean Observation di Jepang selama hampir sebulan. Program ini diselenggarakan oleh Kementrian Riset dan Teknologi dengan pembiayaan dari hibah Bank Dunia (World Bank). BPPT mengirim 20 (dua puluh) orang peneliti dan perekayasa muda ke beberapa institusi di Jepang dengan maksud untuk membangun kapasitas dan kompetensi pribadi dengan mengikuti beberapa program pelatihan singkat disana. Selama hampir sebulan kami mengunjungi beberapa tempat seperti Chiba University, Tokyo, Yokohama dan Hiroshima. Kunjungan tersebut benar-benar merubah motivasi dan cara pandang saya. Mengunjungi salah satu negara maju yang identik dengan teknologi canggih membuat saya menyadari bahwa Indonesia sudah tertinggal jauh secara teknologi dengan negara-negara maju. Dan terlebih itu, kunjungan itu telah memicu saya untuk melanjutkan sekolah lagi di salah satu negara maju yang berarti saya harus mendapatkan beasiswa untuk mewujudkan mimpi saya tersebut.

Setelah itu pada akhir tahun 2013, saya mulai mencoba mempelajari cara-cara mendaftar beasiswa ke luar negeri beserta syarat-syaratnya. Salah satu syarat yang terpenting adalah sertifikat bahasa Inggris bisa TOEFL atau IELTS, tetapi saya baru tahu kalo ternyata IELTS lebih banyak diterima di berbagai negara. Untuk itu saya mulai belajar tentang IELTS yang menurut saya agak aneh karena umumnya dari jaman kuliah kita lebih familiar dengan format TOEFL ITP. Kemudian saya mengikuti kursus persiapan IELTS di IALF Kuningan Jakarta yang biayanya cukup buat bayar kos selama empat bulan...hehe. Selama mengikuti kursus itu saya merasa kaget atau kalo boleh dibilang shock karena beberapa alasan. Pertama, karena format IELTS ternyata sangat berbeda dengan TOEFL. Kemudian, trainer-nya adalah expatriat dari Australia yang bisa dibayangkan menyampaikan materi dengan full English dan aksen Australia yang agak aneh bagi orang Indonesia. Yang ketiga adalah teman-teman sekelas saya yang ternyata sudah pada advanced dan bisa mengikuti setiap materi. Intinya saya merasa gagal pada kursus tersebut tapi paling tidak selama kursus saya sudah memfotokopi banyak buku IELTS dari perpustakaan IALF yang mungkin harganya sangat mahal jika membeli sendiri. Belum lagi biaya tes IELTS yang super mahal membuat saya membanting setir kembali ke TOEFL ITP.

Tahun 2014, berbekal skor TOEFL ITP 507 saya mencoba melamar beberapa beasiswa. Disamping itu dalam tahun itu saya juga mengikuti beberapa tes TOEFL lagi dengan kenaikan skor yang tidak signifikan hanya berkisar 10 point. Sepanjang tahun itu beasiswa yang saya apply diantaranya Australia Award Scholarship, New Zealand Award Scholarship, USAID Prestasi dan Postgraduate Training GEBCO di US yang semuanya berakhir dengan kegagalan. Disamping itu saya juga tetap belajar TOEFL dengan kursus di salah satu tempat kursus inggris di Jakarta dan belajar IELTS secara otodidak.

Tahun 2015 setelah stag belajar TOEFL ITP, saya mencoba untuk kembali ke IELTS dengan mengikuti kursus persiapan IELTS di LBI UI Salemba selama dua kali dengan alasan tempat kursus tersebut relatif lebih murah dibanding tempat kursus IELTS yang lain di Jakarta.  Disamping itu saya juga mengikuti beberapa tes TOEFL lagi dengan kenaikan skor hanya 530. Berbekal skor tersebut saya mencoba apply lebih banyak beasiswa lagi diantaranya Australia Award Scholarship, New Zealand Award Scholarship, USAID Prestasi, Brunei Government Scholarship, Chevening, Korean Government Scholarship, VLROS Belgia, Postgraduate Training GEBCO di US dan Riset-Pro Kementrian Ristek dan semuanya berakhir dengan surat penolakan. Selama itu juga saya belum berani mengambil tes IELTS yang biayanya selangit padahal sudah mengikuti dua kursus lagi. Di tahun tersebut sebenarnya saya berhasil lolos beasiswa USAID Prestasi ke US, tetapi beberapa hari menjelang masa Pre-Departure training mendadak saya jatuh sakit dan harus istirahat beberapa bulan sehingga terpaksa mengundurkan diri dari beasiswa tersebut. Saya juga belum kepikiran untuk mencoba LPDP yang lagi popular saat itu karena skor bahasa Inggris saya masih dibawah persyaratan. Setelah itu saya bertemu secara tidak sengaja di media sosial dengan salah satu guru IELTS yang sekarang menjadi teman baik saya. Beliau adalah salah satu guru IELTS di Indonesia lulusan Cambridge University UK. Saya belajar tips dan rahasia mengerjakan soal-soal IELTS yang tidak saya dapatkan dari tempat-tempat kursus yang saya ikuti sebelumnya. Beliau jugalah yang meyakinkan saya untuk berani mengambil tes IELTS. Akhirnya pada akhir 2015, saya beranikan untuk mengambil tes IELTS dan Alhamdulillah skor saya 6.5 dimana cukup untuk mendaftar beasiswa ke luar negeri.

Berbekal skor IELTS tersebut saya mencoba peruntungan untuk mendaftar beasiswa LPDP 2016 dengan bantuan salah satu teman baik yang sudah menjadi awardee LPDP untuk mengoreksi essay saya. Bersamaan dengan itu saya juga mendaftar beberapa universitas di luar negeri sebagai persiapan aplikasi beasiswa lain jika tidak lolos LPDP dan alhamdulillah surat penerimaan (LoA) dari universitas-universitas tersebut tidak dengan susah saya terima. Sejauh itu saya sudah mengantongi empat LoA dr Universitas di Australia dan Belanda. Berbekal modal tersebut dengan keyakinan pribadi saya mendaftar beasiswa LPDP, Australia Award Scholarship dan Riset-Pro Kementrian Ristek. Singkat kata, kemudian saya mengikuti seleksi beasiswa LPDP dan dinyatakan lolos seleksi beasiswa. Selang beberapa bulan kemudian saya juga dipanggil seleksi beasiswa Australia Award Scholarship dan kemudian dinyatakan lolos seleksi, disamping surat keputusan lolos beasiswa Riset-Pro Kementrian Ristek karena saya sudah mengantongi beberapa LoA dan siap berangkat kuliah di luar negeri. Tanpa mengecilkan kedua beasiswa lain, saya memilih beasiswa Australia Award Scholarship sebagai platform untuk kuliah di Australia karena memang sudah saya idam-idamkan sebelumnya dan untuk mengikuti jejak senior dan inspirator saya, Pak Made Andi Arsana.

To sum up, secara total ada kurang lebih 15 beasiswa yang gagal saya dapatkan sebelum mendapatkan beasiswa tahun 2016. Pernah terbersit di benak jikalau di tahun 2016 saya juga gagal mendapatkan beasiswa di luar negeri, saya akan banting setir kuliah di dalam negeri. Kepada teman-teman pemburu beasiswa, semoga kisah saya ini bisa member semangat dan inspirasi.

Percayalah bahwa jika satu pintu ditutup maka masih ada banyak pintu yang menunggu kita untuk mengetuk dan membukanya….

In life…there is one thing I have learnt and I learnt it in a hard way…

If you fight for what you want the best you could…but you would give the result to Him in humility…

He will listen and help you…(Mr. Y, 2016)

Perth, Feb 2018

End of Summer

The Benefits and Drawbacks of Coastal Development, A General Perception...

Significant development of coastal area has become a major concern in many countries since this area is closely related with diversity and complexity. Saleh et al., (2016: p.2) mention that coastal area as a community that has complex potentials in relation with its development such as social, administrative, physical, economical, political and biophysical perspective. Several issues and impacts have been risen up in line with the development of coastal area. It is argued here that coastal development will be beneficial for residents in some ways. This essay tries to cover both positive and negative impacts as the result of coastal area development including several issues that follow it in environmental, social and economic perspectives.

Economically, coastal area promises many great business opportunities. Thanh (2006: p.1) notes that the wealth of natural resources and other natural conditions benefits has trigged the coastal zone to become an area of active economic development and high population density with the significant growth of water way and ports, agriculture, fisheries, industry, mining, and tourism. In social perspective, coastal development has brought several merits. For instance, Ahmed (2005: p.17), finds in tourism industry that the development of coastal area can establish renewed local pride in their culture and increasing the cross-cultural exchanges among the local people and the tourists. The residents are also benefited with the improvement of infrastructures and transportation facilities. Moreover, he also claims that this development can encourage the growth of traditional festivals and other cultural events in coastal area. This factor can also promote local and traditional crafts and souvenirs.

However, these great improvements have already led to several threats. Thanh (2006: p.1) argues that coastal disasters (floods, erosion, sedimentation, salt intrusion and oil spills), pollution at various levels (oil, organic compounds, pesticide and heavy metals) and damage of habitats and decrease of living organisms are some of the serious consequences as the impacts of economic activities in coastal area. Ahmed (2005: p.16) also identifies in the coastal tourism that the local people will loss of advantages economically if the investors own and manage tourist industry by themselves and not involving local communities. In social context, he also indicates that the residents cannot comfortably use the overdevelopment of supporting facilities, shopping and transportation systems. These improvements also bring several cultural degradations. Ahmed (2015: p.2) believes that the increasing of social degradation and criminality in coastal area happened as the result of the modernization in that area.

There are several approaches that can be taken to minimize those negative effects. Since its complexity, coastal areas need to be managed in an integrated way. One term that has been proposed is Integrated Coastal Zone Management (ICZM).  According to Post and Lundin (1996: p.7), ICZM is government process that covers institutional and legal framework to make sure that the management and development plans of coastal area is integrated with environment and social goals also involving all the stakeholders.

In conclusion, coastal development cannot be avoided as a part of modernization. There are merits and drawbacks as the consequences of this development. I believe, with an integrated and appropriate management system, the development of coastal area will bring many advantages for the residents. 

Selecting an Appropriate Mapping Technology: Drones vs Terrestrial Surveying, A General Perspective

Monitoring and observing the condition of natural resources and phenomenon becomes a major concern in many countries. Fancy et al. (2009) believe that those monitoring programs can help stakeholders to develop an understanding of status and trends of the natural, hence it can be a basis for decision-making for the long-term protection of natural resources such as coral reefs, deserts, arctic tundra, prairie grasslands, caves, and tropical rainforests.  One of the most effective tools to monitor and observe natural condition is by using maps. Mapping of natural condition has become a common strategy in a natural reserve design. Flather et al. (1997) comment that maps can make planners and researchers in a strategic position to describe natural patterns and to study the processes behind the pattern. It is important, then, to understand what kinds of method and technology that can be utilized to create maps. This essay will examine two different mapping technologies, terrestrial survey and Unmanned Aerial Vehicle, in term of efficiency, effectiveness, final maps products, costs and operating limitations then suggest that an Unmanned Aerial Vehicle can be an effective tool in wide areas mapping.

The most common method to survey and map an area is using conventional terrestrial surveying. The terrestrial survey usually uses total station equipment and prism reflectors to measure distance and angle from one point to other points in earth surface. The terrestrial survey needs at least two persons to conduct the survey, one person for operating the total station instrument and another person for taking a prism target to the intended position (Lee et al. 2013). However, in actual condition, conducting terrestrial survey can be more effective by four persons or more. Terrestrial surveying is a famous mapping method for small and narrow areas since it uses simple equipments and conducted by foot survey. Lee et al. (2013) also argue that this method is also very adequate for monitoring natural phenomenon changes in detail at a small area.

UAV or Unmanned Aerial Vehicle or sometimes known as drone is an aerial robot that piloted remotely (Colomina & Molina 2014, cited in ICAO 2011). Klemas (2015) says ‘UAVs are powered aircraft operated remotely or autonomously with preprogrammed flight planning’. This technology can be used to obtain high-resolution earth surface images at a lower cost so it can increase operational flexibility and bigger adaptability. As a final result, data that obtained from UAV can be created as maps then can be a powerful tool to monitor and to observe environment phenomenon.

Firstly, efficiency is an important factor in surveying and mapping. UAV technologies are more efficient than terrestrial surveying since this technology can minimize time consumption and improve cost-effectiveness (Tapete et al. 2015, cited in Liu & Yang, 2015). Koh & Wich (2012) have proven with their drone equipment that used for rainforest mapping in Sumatra, Indonesia that it can fly autonomously for a total flight time of 25 minutes and can cover a distance of 15 km. In addition, UAV systems have better coverage of mapping than terrestrial survey. For instance, in 2012, Zarco-Tejada et al. (2014) conducted research about the use of AUV for olive orchards plants mapping in Alcolea, Cordoba, Southern Spain. Using a UAV system that has approximately 63 km/hours of ground speed and flight 200 m above land surface then the maps that generated for one area can cover 92.58 ha and the map has an overlap 80 – 90 % between each other. It means that in one time of flight, this equipment can map and cover wider coverage areas than a terrestrial survey. The coverage superiority and time saving are some evidence that UAV system is an efficient technology for mapping.

On the other hand, terrestrial survey method has lower time consume than UAV survey. A terrestrial survey requires at least four persons to conduct the survey to get an optimal field operation. Hill & Geosystems (2008) have proven by conducting a topographic survey of a car park with 0.57 hectare using terrestrial survey and total time consume was 135 minutes. Similarly, Lee et al. (2013) conducted a survey study in Gosapo Beach, the west coast of Korea. This area is characterized by the macro-tidal condition with a maximum tidal range over 6 m during the spring tidal period, which means that during high tide, the survey operation cannot be done because all of the coastal lines are covered by water. Lee has proven that using terrestrial survey with four survey persons and the time efficiency is just 10 meters per minute. Koh & Wich (2012) also report in his study of assessment and monitoring of Orang Utan populations in Sumatra, Indonesia that using ground surveys can cost up to $250,000 for a two-year survey cycle. It means that terrestrial survey is time-consuming, financially expensive, and logistically challenging in remote areas. Due to this high cost, surveys cannot be conducted regularly and as a result, governments and researchers will lack appropriate data for analysis and monitoring of population trends.

Secondly, a UAV system can cover of difficult and dangerous areas effectively since it uses an unmanned vehicle that can fly far from the operator so the operator itself can be placed in a safe location. These remote areas are difficult to access and consequently, study and monitoring of these areas are impossible to be done. ‘some remote tropical forests have never been surveyed for biodiversity due to difficult and inaccessible terrain’ (Koh & Wich 2012, cited in Palace, M. et al. 2008).  UAVs also have been proven as an effective tool to map a dangerous location. For example, UAVs have replaced manned aircraft in studies of remote and dangerous areas, such as the complex coastal topography and polar regions (Klemas 2015). Another example in Japan in 2011 when earthquake and tsunami hit Fukushima Daiichi Nuclear Power Plant on Japan’s eastern coast and released significant quantities of radioactive material. After that incident, (Martin et al. 2016) conducted high-resolution radiation mapping using a UAV system to remedy large contaminated region of Japan surrounding the Fukushima Plant. The survey then successfully record and map contamination at the meter scale and furthermore chooses some appropriate remediation actions for the site. That action, of course, cannot be done by foot-based surveying like terrestrial survey since it can be very dangerous for human to enter the radiation contaminated areas. In the future, water environment emergency monitoring method using UAV system is still explored and will be developed (Liu et al. 2010).

Thirdly, UAV offers variety products not only contour maps but also three-dimensional maps and photographic maps, then these maps can be combined with other data using GIS software. Fedra & Feoli (1998) explain that a geographic information system (GIS) consist of several software tools can be utilized to obtain, handle, process and display geographical data. Papakonstantinou et al. (2016) show in a survey that conducted in Eressos and Neapolis coastline, Greece in 2015 that UAV system can be a powerful tool for classification, generates 3D images and maps of coastal morphology, so it can be used for analyzing changes in coastal monitoring such as erosion in coastal zones. It then can be a powerful tool in urban and environmental planning. Grecea et al. (2016) suggest that 3D models of objects from UAV survey also can be combined with other data using a web Geographic Information System (GIS) then this information system can be accessed on-line by many stakeholders for many purposes. On the other hand, terrestrial survey can only create limited products than UAV system since the survey equipments are much simpler than UAV technology. In general, the data processing steps are only downloading data from survey equipment, process the data using simple software and creating two-dimensional contour maps (El et al. 2002).

Fourthly, another thing that should be considered in choosing a mapping method is products and operation cost. UAVs system consists of several high-technology equipments such as unmanned aircraft, Global Navigation Satellite Systems (GNSS) such as GPS and Inertial Navigation Systems (INS) which is used to keep the UAV remains stable (Colomina & Molina 2014). Those equipments are not cheap and need adequate money investment to get it. Klemas (2015) illustrates that a cheap UAV system has a price over than $10,000 and the price depends on their capability, stability, range and instrument payload. Neitzel & Klonowski (2012) also argue that the cost of UAV survey can be approximately 100,000 euros which means that only a small number of countries can spend their money easily for this kind of survey. However, Koh & Wich (2012) from Department of Environmental Systems Science, ETH Zurich, Switzerland have developed a low-cost unmanned aerial vehicle for surveying and mapping forests and biodiversity with total cost is just around $2,000. It means that in the future the low-cost UAV will be developed further; hence it can encourage many countries to use this technology. On the other hand, the price of one set of terrestrial survey equipment is just around $5,000. As a result, this equipment is more affordable than a UAV system and many companies and institutions have owned it.

Lastly, operating a UAV equipment is not as simple as our imagination and there are many challenges to operating it. Albaker & Rahim (2009) believe that the ability to navigate in urban or unknown terrain is very important in a UAV survey since there are many different types and sizes of obstacles that can endanger the equipment. Although a UAV system has tools to be used in difficult terrain, a good piloting skill of its operator is compulsory otherwise the equipment can hit or drop in a remote area that can lead to the damage of the equipment. In addition, Siebert & Teizer (2014) note that strong thermal winds can cause air turbulences for the UAV. Wind gusts of more than 40 km/h can endanger to the UAV and the survey needs to be canceled. They also suggest that high-populated areas need to be avoided in UAV survey since there are many bystanders (pedestrians or other traffic) that can be endangered. Other environmental hazards such as trees and building also should also be avoided during the survey, the potential of collision to these obstructions can endanger the equipment. Another factor that should be counted is equipment’s power supply. Simic et al. (2015) investigate that the electric power supply is another important limitation for UAV survey and it can influence to its range and endurance. As increasing battery system size is not a suitable solution due to its weight, so they conducted research to investigate the possibility of using wireless energy transfer to UAV during the survey via electrical power transmission. In contrast, a terrestrial survey can be conducted much simpler than UAV survey. The terrestrial survey can be conducted easier in areas with complex topographic terrain, many environmental obstacles and high populated. The main obstacle of the terrestrial survey is only the weather since the equipment is usually not water resistant so the survey cannot be conducted during the rain.

In conclusion, there are several methods and technologies that can be used to map areas for monitoring and planning purposes. Two of those technologies that have been used widely in many countries are conventional terrestrial surveying and unmanned aerial vehicle. Each of these technologies has own strengths and weaknesses. While terrestrial survey has a predominance to be used in small areas, UAV offers benefits to map large and restricted areas also it can produce a variety of attractive maps.

References

Albaker, B.M. & Rahim, N.A., 2009. A survey of collision avoidance approaches for unmanned aerial vehicles. International Conference for Technical Postgraduates 2009, TECHPOS 2009, (January).

Colomina, I. & Molina, P., 2014. Unmanned aerial systems for photogrammetry and remote sensing: A review. ISPRS Journal of Photogrammetry and Remote Sensing, 92, pp.79–97. Available at: http://dx.doi.org/10.1016/j.isprsjprs.2014.02.013.

El, P. et al., 2002. GPS and Total Stations Data Acquisition and Processing Methodology for Automatic Drawing of Topographic Plans Using ArcCOGO. FIG XXII International Congress, pp.1–13.

Fancy, S.G., Gross, J.E. & Carter, S.L., 2009. Monitoring the condition of natural resources in US national parks. Environmental Monitoring and Assessment, 151(1–4), pp.161–174.

Fedra, K. & Feoli, E., 1998. GIS technology and spatial analysis in coastal zone management. EEZ Technology, pp.171–179.

Flather, C.H. et al., 1997. Identifying gaps in conservation networks: Of indicators and uncertainty in geographic-based analyses. Ecological Applications, 7(2), pp.531–542.

Grecea, C., Herban, S. & Vilceanu, C.-B., 2016. WebGIS Solution for Urban Planning Strategies. Procedia Engineering, 161, pp.1625–1630. Available at: http://linkinghub.elsevier.com/retrieve/pii/S1877705816328661.

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Klemas, V. V., 2015. Coastal and Environmental Remote Sensing from Unmanned Aerial Vehicles: An Overview. Journal of Coastal Research, 315(5), pp.1260–1267. Available at: http://www.bioone.org/doi/10.2112/JCOASTRES-D-15-00005.1.

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Lee, J.M., Park, J.Y. & Choi, J.Y., 2013. Evaluation of sub-aerial topographic surveying techniques using total station and RTK-GPS for applications in macrotidal sand beach environment. Journal of Coastal Research, 65(65), pp.535–540. Available at: http://www.bioone.org/doi/10.2112/SI65-091.1.

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Martin, P.G. et al., 2016. High-resolution radiation mapping to investigate FDNPP derived contaminant migration. Journal of Environmental Radioactivity, 164, pp.26–35. Available at: http://dx.doi.org/10.1016/j.jenvrad.2016.06.025.

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Papakonstantinou, A., Topouzelis, K. & Pavlogeorgatos, G., 2016. Coastline Zones Identification and 3D Coastal Mapping Using UAV Spatial Data. ISPRS International Journal of Geo-Information, 5(6), p.75. Available at: http://www.mdpi.com/2220-9964/5/6/75.

Siebert, S. & Teizer, J., 2014. Mobile 3D mapping for surveying earthwork projects using an Unmanned Aerial Vehicle (UAV) system. Automation in Construction, 41(October), pp.1–14.

Simic, M., Bil, C. & Vojisavljevic, V., 2015. Investigation in wireless power transmission for UAV charging. Procedia Computer Science, 60(1), pp.1846–1855. Available at: http://dx.doi.org/10.1016/j.procs.2015.08.295.

Tapete, D. et al., 2015. Localising deformation along the elevation of linear structures: An experiment with space-borne InSAR and RTK GPS on the Roman Aqueducts in Rome, Italy. Applied Geography, 58, pp.65–83. Available at: http://dx.doi.org/10.1016/j.apgeog.2015.01.009.

Zarco-Tejada, P.J. et al., 2014. Tree height quantification using very high resolution imagery acquired from an unmanned aerial vehicle (UAV) and automatic 3D photo-reconstruction methods. European Journal of Agronomy, 55, pp.89–99. Available at: http://dx.doi.org/10.1016/j.eja.2014.01.004.