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Analysis of Students’ Difficulties about Rotational Dynamic Topic Based on Resource Theory Rahmawati, I.; Sutopo, S; Zulaikah, S.
Jurnal Pendidikan IPA Indonesia Vol 6, No 1 (2017): April 2017
Publisher : Program Studi Pendidikan IPA Fakultas Matematika dan Ilmu Pengetahuan Alam (FMIPA)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jpii.v6i1.9514

Abstract

Students’ difficulties commonly are analyzed based on misconception theory. This paper aimed to analyze students’ difficulties on the rotational dynamic based on resource theory. The subject of research consisted of 108 first-year undergraduate students of Physics Education, State University of Malang. Firstly, the students were asked to solve 15 multiple-choice questions and gave open explanation. We then implemened a constant comparative method to identify and categorize some resources that students employed in solving several problems that most the students failed to respond correctly. The results indicated that the students had difficulties in solving problems related to the torque and the equilibrium of rigid body. The students’ difficulties were not merely caused by the lack of correct knowledge. Instead, they have the correct knowledge or resources but they activated them on inappropriate context. The students will be successfully used the resources to solve problems if they activated them in the right context.
Analysis of Students Difficulties about Rotational Dynamic Topic Based on Resource Theory Rahmawati, I.; Sutopo, S; Zulaikah, S.
Jurnal Pendidikan IPA Indonesia Vol 6, No 1 (2017): April 2017
Publisher : Program Studi Pendidikan IPA Fakultas Matematika dan Ilmu Pengetahuan Alam (FMIPA)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.15294/jpii.v6i1.9514

Abstract

Students difficulties commonly are analyzed based on misconception theory. This paper aimed to analyze students difficulties on the rotational dynamic based on resource theory. The subject of research consisted of 108 first-year undergraduate students of Physics Education, State University of Malang. Firstly, the students were asked to solve 15 multiple-choice questions and gave open explanation. We then implemened a constant comparative method to identify and categorize some resources that students employed in solving several problems that most the students failed to respond correctly. The results indicated that the students had difficulties in solving problems related to the torque and the equilibrium of rigid body. The students difficulties were not merely caused by the lack of correct knowledge. Instead, they have the correct knowledge or resources but they activated them on inappropriate context. The students will be successfully used the resources to solve problems if they activated them in the right context.
SISTEM PENYARADAN PADA EKSPLOITASI HUTAN PINUS DI JAWA TENGAH Sutopo, S; Idris, Maman M
Jurnal Penelitian Hasil Hutan Vol 2, No 3 (1985): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1985.2.3.1-9

Abstract

A paper  mill  is to  be erected  in Cilacap, Central Java in the near future. The raw material  must  come  from  the hilly pine  forests  in  the  Pekalongan  and Banyumas  area. The  mills daily intake ranges between 1,000-1,500 m3 of  relatively small  diameter  pine  logs. Therefore manual yarding  system  must  be improved  to increase its productivity. One way to do this is to yard  with a  wheeled  cariage.The purpose of this investigation  is to  determine the feasibility of  this yarding system in hilly pine forest terrain. The investigation reveals the following   :Yarding system by  Roda II is favourable  in  the  hilly pine  forest area in Central Java.This system increases  the  income  per  manday  approximately  by 31%  compared to the  traditional system (ngglebeg) for a  distance of  1,0 km,  and  18%  for a distance of  2.0 km.Yarding productivity by Roda II is approximately  1.58  m3 per day.
Lapisan Perkerasan Komposit Batu Pecah pada Kontruksi Jalan Hutan Rahardjo, Rahardjo; Suparto, S; Sutopo, S
Jurnal Penelitian Hasil Hutan Vol 4, No 2 (1987): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1987.4.2.50-55

Abstract

The use of pavement in Indonesian forest road construction at present is not common practice. Paving of logging roads is still considered too expensive, especially when its construction is not rational and effective. Information on pavement design especially with regard to its composition should help forest companies in solving their forest road construction problems.This investigation looks into the problem of finding the proper composition of crushed gravel and sand or rock dust for the construction of pavements. This kind of pavement is thought to have high shearing strength, stability and density.A series of laboratory test were conducted for this purpose, employing factorial analysis .A performance test in the field was conducted to compare with the Telford system using paired samples.The investigations revealed the following:- Crushed rock had significant influence on the shearing strength of the pavement. This material mixed with rock dust showed significant interaction.- Rock dust itself and water did not have significant effect on the shearing strength of pavement.- The use of water may help  facilitate the compaction process guiding the filler material into the voids among the crushed rock particles.- The proper composition turned out to be three units of crushed rock and two units of rock dust, resulting in a shearing strength of 0,226 kg/cm2.- Crushed rock composite made better pavement than the Telford system, resulting in lower settling of subgrade.- Based on the above, it is recommended to use a mixture of 2-3size crushed rock and rock dust in the proportion of 3 : 2 for pavement of forest roads, using smooth drum roller to obtain proper compaction.
STABILISASI TANAH LIAT DENGAN KAPUR PADA KONSTRUKSI BADAN JALAN HUTAN DI PULAU LAUT Suparto, Rahardjo S; Sutopo, S
Jurnal Penelitian Hasil Hutan Vol 1, No 2 (1984): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1984.1.2.11-22

Abstract

Subgrade  construction is an important part in forest  road building,  Subgrade soils with a high clay content  could  not be used satisfactorily as forest  road construction material  unless it is treated  to increase its stability.  The improvement of the  physical characteristics of clay  soils  related  to  subgrade  construction  can  be achieved  by  mixing  lime  of certain proportion into   the soil. The purpose of this investigation  is to determine the amount  of lime required for subgrade stabilization  which  have high clay content  in Pulau Laut,  South  Kalimantan The investigation  reveals the following :1.  The  efective  amount   of  lime  stabilization of  soils  is 7 percent of  the dry  weight  of  the  soil, resulting  in the following  physical  properties  :-  Bearing capacity  is 167 kg/cm2 at air dry  condition,-  Percent  of swell is 2.3,-  Plasticity index  is 25.5,  and-  pH is 9.00.2.  Stabilization   with  7 percent  lime is most  effective  for use in forest  road subgrade containing  about  66% clay. 
PENGARUH KERUSAKAN DAN KELERENGAN JALAN HUTAN TERHADAP PRODUKTIVITAS PENGANGKUTAN KAYU STUDI KASUS DI KALIMANTAN BARAT Sutopo, S; Suparto, Rahardjo S
Jurnal Penelitian Hasil Hutan Vol 5, No 7 (1988): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1988.5.7.420-424

Abstract

Timber transportation   productivity  decreases  when  forest  road  is  deteriorated   and  the  8lope  is large. This  study tried  to  investigate  the  effect  of  slope  and road  damage  on  timber  transportation  productivity,  and was carried out at the PT Sari Bumi  Kusuma  forest  company   areas in  West Kalimantan in  1987.The  investigation   results are as follows:Slope difference of  5% has significant   effect  on  transportation  productivity.  On  flat,   medium   and  steep  slopes, the productivities  are 265,   219 and  132  m3.  km/hr,   respectively.Transportation   productivity  is significantly influenced   by  a difference  of  15% damage  on  the  road. Productivities on  relatively   good  road, medium damaged  and  badly  damaged  roads  are  292,213  and  136 m3.km/hr, respectively.On flat  and  badly  damaged  roads  (at a damage  level greater  than  30%),   transportation  productivity  is reduced  64% which  caused  significant   financial  loss.  The  allowable  road damage  on  (at  terrain  without   causing financial  loss is 40%.On  medium   terrain  and  medium   damaged  roads  (at  damage  levels  between 15% and  30%), the  loss is significant. Medium damaged  (between 15%  and  30%) and heavy  damaged roads (greater than 30%) caused  transportation productivities  to  be decreased  as much as 25% and 58%,  respectively,   The allowable  road damage on medium   terrain without   causing financial  loss is 26%.On steep  terrain,   transportation   productivity is decreased  significantly i.e. 58% of  those on medium  damaged  roads (between   15% and  30%).  A  maximum   road damage  of  18%  is allowable  without  causing financial  loss.There  is  a significanf   interaction   between  slope  and road  damage.  The  steeper  the  slope  and  the  heavier  the  road damage,  the  larger  the  decrease in  transportation   productivity.In  the  transportation   distance of 60 km  and  the  timber  price  of  US$ 70/m3,  if timber  transportation  productivity decreases 30%,  it is strongly  suggested  to  repair damaged  road  immediatly   in order  to prevent   financial  losses.
PENGGUNAAN TANAH LIAT SEBAGAI BARAN KONSTRUKSI LAPISAN AUS JALAN HUTAN Using clay. soil for wearing course material of forest roads Sutopo, S
Jurnal Penelitian Hasil Hutan Vol 8, No 3 (1990): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1990.8.3.109 - 114.

Abstract

Oil type  of forest areaB in Indonesia is dominated by  c"lay.  This soil is poor. when used a  forest road construction material but its engineering properties can be improved by certain treatments.C"lay soils can be used aB binding materialaof wearing course construction. An investigation wa. carried out, using the mi:cture of soil, lime and crushed rock with the following results: 1. Lime haB a highly significant influence on the binding strength of materaUfor wearing course of forest road& It proportion is 1~  on weight bas~.                                    2. According to laboratory test, the use of cruthed rock has a highly significant influence on wearingcource  tre"lth.Percentagesof separated materials at 0%. 2590. 50% and 75% cmshed rock mixture are 1,0%. 2,5%, 26,B'foand 66.5%reapectively.3. An effective crushed rock percentase for clay 11oil wearingcourse construction is 25%. Among the material mixtUre(soU, lime and cmshed rock) have significant interaction.       
KEMUNGKINAN PENGGUNAAN LATEX UNTUK STABILISASI BADAN JALAN HUTAN Suparto, Rahardjo S; Sutopo, S
Jurnal Penelitian Hasil Hutan Vol 3, No 3 (1986): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1986.3.3.13-18

Abstract

Among  the many known  stabilized methods  and materials that can be applied to improve forest  road stability,  latex is thought  of as one such material  that deserves trying.   This experiment  is to asses the possibility  of  using latex as a stabilizing  agent,The fol/owing   conclusions  are in order: Latex  can be used as stabilizing  agent for  clayey soils as subgrade  material.  A  4% latex content turned out to be effective  to keep swelling,  due to soaking  in water,  within a limit of 4,3%. Degree of compaction  has no significant  effect  of swell.  Degree of  compaction  and percentage  of  latex  content  has significant  effect  on bearing capacity.  Latex  may  be recommended   as an alternative  material for  stabilizing subgrade soil in forest  road construction.
PENGARUH APLIKASI PUPUK POLYHALITE DAN KCL TERHADAP KADAR K DAN PERTUMBUHAN BIBIT TANAMAN JERUK PAMELO (CITRUS MAXIMA) DI KEBUN PERCOBAAN BALITJESTRO, BATU Suntari, Retno; Sutopo, S; Maudyansa, Aryo Gilang
Jurnal Tanah dan Sumberdaya Lahan Vol 7, No 1 (2020)
Publisher : Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/ub.jtsl.2020.007.1.11

Abstract

There are still many farmers in Indonesia who use a single fertilizer such as N, P, or K fertilizer. While the needs of plant nutrients are not only that nutrients but also other macronutrients. One of single fertilizer used is KCl fertilizer which only contains essential K nutrients and micro Cl nutrient elements. To overcome this problem, another source of K fertilizer that does not contain Cl is used, especially in Pamelo citrus nurseries. POLY4 fertilizer is used as a source of K nutrients, because it has an excess of containing several nutrients such as K (14%), Ca (17%), Mg (6%), and S (19%). This research was conducted at the BALITJESTRO screen house and the Soil Department Laboratory, Faculty of Agriculture, Brawijaya University. The research design used was a completely randomized design with 5 treatments i.e P0 (100% MOP), P1 (50% POLY4 + 50% MOP), P2 (100% POLY4), P3 (150% POLY4), and P4 (200% POLY4). Parameters of this research were plant height, numbers of leaf, soil pH and exchangeable K, and K content in plant. Result of this study indicated that application of 50% POLY4 + 50% MOP (642 kg ha-1 POLY4 + 150 kg ha-1 MOP) significantly affected the height and number of leaves of Pamelo orange seedlings in 12 weeks, respectively 6.39% and 13.6 % compared to 100% MOP/control (300 kg ha-1 MOP). Application of 150% POLY4 (1,927 kg ha-1 POLY4) significantly increased plant K level by 9.40% compared to control (300 kg ha-1 MOP). Application of POLY4 fertilizer had no significant effect on pH and exchangeable K. The best dose of fertilizer in Pamelo citrus nurseries is the application of POLY4 642 kg ha-1 POLY4 + 150 kg ha-1 MOP (50% POLY4 + 50% MOP).
PENGARUH KERUSAKAN DAN KELERENGAN JALAN HUTAN TERHADAP PRODUKTIVITAS PENGANGKUTAN KAYU STUDI KASUS DI KALIMANTAN BARAT Sutopo, S; Suparto, Rahardjo S
Jurnal Penelitian Hasil Hutan Vol 5, No 7 (1988): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3243.007 KB) | DOI: 10.20886/jphh.1988.5.7.420-424

Abstract

Timber transportation   productivity  decreases  when  forest  road  is  deteriorated   and  the  8lope  is large. This  study tried  to  investigate  the  effect  of  slope  and road  damage  on  timber  transportation  productivity,  and was carried out at the PT Sari Bumi  Kusuma  forest  company   areas in  West Kalimantan in  1987.The  investigation   results are as follows:Slope difference of  5% has significant   effect  on  transportation  productivity.  On  flat,   medium   and  steep  slopes, the productivities  are 265,   219 and  132  m3.  km/hr,   respectively.Transportation   productivity  is significantly influenced   by  a difference  of  15% damage  on  the  road. Productivities on  relatively   good  road, medium damaged  and  badly  damaged  roads  are  292,213  and  136 m3.km/hr, respectively.On flat  and  badly  damaged  roads  (at a damage  level greater  than  30%),   transportation  productivity  is reduced  64% which  caused  significant   financial  loss.  The  allowable  road damage  on  (at  terrain  without   causing financial  loss is 40%.On  medium   terrain  and  medium   damaged  roads  (at  damage  levels  between 15% and  30%), the  loss is significant. Medium damaged  (between 15%  and  30%) and heavy  damaged roads (greater than 30%) caused  transportation productivities  to  be decreased  as much as 25% and 58%,  respectively,   The allowable  road damage on medium   terrain without   causing financial  loss is 26%.On steep  terrain,   transportation   productivity is decreased  significantly i.e. 58% of  those on medium  damaged  roads (between   15% and  30%).  A  maximum   road damage  of  18%  is allowable  without  causing financial  loss.There  is  a significanf   interaction   between  slope  and road  damage.  The  steeper  the  slope  and  the  heavier  the  road damage,  the  larger  the  decrease in  transportation   productivity.In  the  transportation   distance of 60 km  and  the  timber  price  of  US$ 70/m3,  if timber  transportation  productivity decreases 30%,  it is strongly  suggested  to  repair damaged  road  immediatly   in order  to prevent   financial  losses.