JaLCDOI 10.18926/fest/11477
Title Alternative Efficient Chain Extension Reaction of Poly (butylene terephthalate) by using Crystallization
FullText URL 012_167_171.pdf
Author Ihara, Seiji| Shiroma, Hisashi| Yamazaki, Shinichi| Kimura, Kunio|
Abstract Plastics are quite important materials for not only industrial usages but also our daily life. Many plastics are difficult to reuse because they are susceptible to UV, hydrolysis and so on leading to the reduction of molecular weight. Among them, poly (butylenes terephthalate) (PBT) is a valuable materials prepared by polycondensation reaction, and PBT has the same limitation to reuse. Hence, efficient chain extension reaction for recovered PBT has been needed to improve the properties damaged by chain scission. In this study, new chain extension reaction had been examined by using crystallization as pre-treatment. Isothermal crystallization at 161℃ concentrated the chain end-groups on the surface of the crystals, and chain extension reaction at 210℃, which was lower than the melting temperature of PBT, enhanced the molecular weight significantly compared with the reaction over the melting temperature. It concluded that the pre-treatment of crystallization was favorable for the efficient chain extension reaction and this result provided the new technology for the effective reuse of the plastics.
Keywords Polyester material recycle crystallization chain extension reaction
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 167
End Page 171
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002314029
JaLCDOI 10.18926/fest/11475
Title Alternative Material Recycling of Municipal Waste Slags by Using Phase Separation of Glass
FullText URL 012_161_165.pdf
Author Imaoka, Takuya| Sakida, Shinichi| Nanba, Tokuro| Miura, Yoshinari|
Abstract A novel recycling process of municipal waste slags obtaining Fe-free colorless materials was developed by using a phase separation of borosilicate glass. B(2)O(3) was added to a simulated waste slag to promote the phase separation. The slag glasses were heat-treated above glass transition temperatures, from which phase separation was successfully induced. The phase-separated slag glasses were still colored in black due to Fe ions, and after soaking in acid, they were successfully bleached, obtaining colorless solids. According to compositional analyses, no Fe ions were confirmed in the remaining insolubles, indicating that Fe ions were preferentially incorporated into the borate-rich phases soluble in acid. The main constituent of the colorless solids was SiO(2) and the end products obtained in the present process were expected as an alternative of pure silica glass.
Keywords slag recycling colorless glass phase separation
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 161
End Page 165
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313957
JaLCDOI 10.18926/fest/11473
Title Alternative Acceleration of Formation of Shish under Flow by Addition of Irregular Shaped Particles
FullText URL 012_157_160.pdf
Author Yamazaki, Shinichi| Wakabayashi, Kanji| Mizuma, Kenta| Kimura, Kunio|
Abstract We have shown that the shish was formed from the oriented melt composed of the elongated chains caused by dust particles within the melt via bundle typed nucleation under flow with low shear rate (γ=5s(-1)). This implies that dust particles effectively cause the elongation of chains within the melt. In this work, we observed the crystallization of polypropylene added with irregular shaped particles under shear flow by means of polarizing optical microscope. We prepared various shaped particles such as confetti-like, spherical and rock-like. We found that the size and asymmetric shape of additive particles play an important role for the acceleration of formation of shish.
Keywords shish crystallization polypropylene shear flow elongation injection molding
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 157
End Page 160
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313610
JaLCDOI 10.18926/fest/11471
FullText URL 012_151_156.pdf
Author Chetin Amine Cifci| Ichiminami, Fumikazu|
Abstract More than billions of years, Earth activity and earthquakes have functioned as the most important part in shaping the physical features of our Earth, on both social life and environment. Its unavoidable results always change life styles and city's structures with its positive and negative effects. To diminish those negative effects or avoid precise earthquake hazard, informing society is very crucial that the strong awareness decreases the risk as seen from past experiences all around the world. The research technique is functioned as questionnaire and applied in the area to achieve more realistic information and to maintain the essential arguments. All along the study, it is tried to think up the earthquake phenomena well known and straightforwardly recognized by a considerable quantity of people. Consequently, it is observed in this study that; firstly, telecommunication is most selected item both before and after earthquake in the point of its effectiveness. Secondly, telecommunication tools more preferable though, public announcement more trusting for society as power of affection on personal decision mechanisms. Thirdly, as a new tendency after earthquake, internet preference increased by means of information source about earthquake.
Keywords Awareness of earthquake Importance of information Relative reliability of sources Internet and public announcement
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 151
End Page 156
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313418
JaLCDOI 10.18926/fest/11467
Title Alternative Rows-of-houses Preservation in Maniwa City of Katsuyama Area, Okayama Prefecture
FullText URL 012_141_149.pdf
Author Luo, Yanjuan| Ichiminami, Fumikazu|
Abstract The aim of the study is to explain the present condition of the rows-of-houses preservation policy of Okayama Prefecture and to examine the samples in Maniwa city, Katsuyama area. Besides, the interview investigation was mainly conducted for residents in the rows-of-houses of preservation area in Katsuyama for giving the concluding remarks about the findings. The traditional private houses in Katsuyama preservation area were partially restored in the 1985-89 and 1993-97 fiscal years by the subsidy from the prefecture. Furthermore, Katsuyamacho at that time founded the subsidy system for maintaining rows-of-houses preservation area (about 25.3 ha) independently in 1993, restored 9 private houses, and made and updated the shop curtains; "Noren". In the point of the observable items, the ground warehouse of structures with gable tile-roofing is visible and it is also in use. Moreover, a latticed window structure, a white wall, and a sea cucumber wall constitute the charm of new rows-of-houses. A stone pavement follows on the riverside at the site facing the Asahi River. There are the remains of an arrival-and-departure place of a flat boat and a brewery, etc. According to our investigation in 2002, the residents were satisfied with "It is easy to live quietly", "the beauty of a natural landscape", "harmony of rows-of-houses and a shop curtain", and "a historical atmosphere", but the recognition of "the creation of active rows-of-houses" was unexpectedly low. Therefore, cooperation between residents and informational sharing are much more required. Consequently, since both the visitors and the residents are satisfied very much with each facilities, such as the whole rows-of-houses, a samurai residence, a brewery, and a restaurant etc., town planning is well organized and attained the priority targets.
Keywords Rows-of-houses Preservation Katsuyama area Visitors Residents
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 141
End Page 149
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313778
JaLCDOI 10.18926/fest/11465
Title Alternative A Survey Study of Residential Awareness on Utilization Function of Agricultural Water and Its Maintenance --A case study in Niwase and Natsukawa of Okayama City, Okayama Prefecture
FullText URL 012_131_140.pdf
Author Makino, Tota| Matsuoka, Takanobu| Qi, Zhiyong| Shinabe, Yosihiro|
Abstract The agricultural water has manifold functions for farming at community level. However, along with the difficulties to maintain the agriculture water path that are caused by the decreasing of farmers and the aging of the society, the agricultural water is losing its functions even that as water resource for local community. This paper presents a survey of the residential awareness on regional water utilization to find the possibility for the maintenance of agricultural water path. Economic evaluation is tried for the regional warter utilization function. This study is carried out at a regional level that covers both farming households and non farmers. Following three points can be confirmed based on the results of questionnaire survey. Firstly, local citizens admit that the agricultural water does have some values (3,037 Yen per household per year). Secondly, the higher the environmental awareness is, and the longer the citizen has lived there, the higher evaluation to function of the agricultural water can be observed. Thirdly, even within those who is holding high evaluation to the agricultural water, it is thought to be quite difficult to maintain the agricultural water path due to the aging of the society and uneven distribution of the participants.
Keywords agricultural water manifold functions for farming at community level local citizens maintenance Contingent Valuation Method
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 131
End Page 140
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313592
JaLCDOI 10.18926/fest/11462
Title Alternative Comparison of micrometeorological environments inside and outside an oriental pickling melon greenhouse.
FullText URL 012_125_130.pdf
Author Morimoto, Yuji| Hirano, Emi| Miura, Takeshi|
Abstract The use of greenhouses has rapidly increased after 1965, and the area became 11 times of 1965 as of 2001. Meteorological conditions and soil moisture environments inside a greenhouse are significantly different from those in the open field. These differences should be understandable to establish accurate predictions of water consumption and evapotranspiration inside a greenhouse which play important roles in the design of any irrigation system. This study aims to estimate the micrometeorological conditions inside an oriental pickling melon greenhouse which can be used for evapotranspiration calculations. Therefore, micrometeorological data were measured inside and outside the greenhouse for the comparison purposes. The results of this study may be summarized as: (1) Solar radiation inside the greenhouse was decreased about 30% of that of outside it by plastic film and frame. (2) Net radiation during the daytime inside the greenhouse was almost the same as the absorbed total short-wave radiation. (3) The difference of daytime mean air temperature inside and outside the greenhouse was between 3 and 4 degree Celsius in day average. (4) Both relative humidity and saturation deficit inside the greenhouse were higher than outside, and those were affected by ventilation. (5) Wind speed inside the greenhouse was greatly affected by opening rate of the house side.
Keywords greenhouse micrometeorology oriental pickling melon
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 125
End Page 130
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313863
JaLCDOI 10.18926/fest/11460
Title Alternative Measurement of root system with growth of oriental pickling melon.
FullText URL 012_119_123.pdf
Author Hirano, Emi| Morimoto, Yuji| Miura, Takeshi|
Abstract It is important to clarify how the soil moisture changes by irrigation and how moisture is consumed by absorption of root, to plan irrigation appropriately in upland field. And, it is thought that clarifying the growth of the root can be important information in the water management, because the amount and the pattern of root water uptake change depending on the growth stage. However, there are not too much a lot of researches that measure the root, in addition, the example intended for crops of 'Gourd family (scientific name:Cucurbitaceae)' is not found. Therefore, for oriental pickling melon, it measured how for the root system to grow up as crop grew every three weeks. The results of this study may be summarized as: 1) Root amount increased with the growth of crops, and the majority of the root existed to 20cm in depth. A lot of rootlets with the role of water uptake existed outside of from 10 to 20cm. 2) Root length has grown up in horizontal and vertical direction at a dash at the stage of growing initial. 3) It was able to be confirmed to the growth of the ground part and the root that the length and amount either also had implications. Moreover, root amount and plant caver ratio drew similar curve.
Keywords root growth oriental pickling melon
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 119
End Page 123
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313695
JaLCDOI 10.18926/fest/11454
FullText URL 012_107_117.pdf
Author Akhtar M. Shahbaz| Oki, Yoko| Adachi, Tadashi| Khan Md. H. R.|
Abstract Acclimation to orthophosphate (Pi) deprivation via highly coordinated Pi-starvation induced (PSI) classical mechanisms such as copious quantities of H(+) and carboxylates (OAs) exudation, remodeling and modification of root architecture by increasing structural and functional plasticity, enhanced uptake rate and increased synthesis of Pi transporters would reduce or eliminate our current overreliance on expensive, polluting, and nonrenewable Pi-fertilizers. These complicated but elegant morphological, physiological, biochemical and molecular adjustments of Pi-starved plants provide an excellent example of how the unique flexibility of plant metabolism and energy transduction helps them to cope in a typically stressful environment. Pi-starved roots possess enhanced H(+)-ATPase and PEPCase which could result in increasing H(+) efflux and OAs exudations in the root vicinity. This would lead to the rhizosphere acidification, which thereby contribute to the solublization and assimilation of mineral Pi from environment. To visualize the dissolution of sparingly soluble Ca-phosphate and rhizospheric pH changes (in situ), genetically diverse Brassica cultivars were grown on agar media. Newly formed Ca-phosphate was suspended in agar containing other essential nutriens. With NH(4)(+) applied as the N source, the precipitate dissolved in the root vicinity and this was ascribed to acidification. No dissolution was occurred with No(3)(-)-nutrition. In order to observe the pH changes at the media-root interface (rhizosphere), an image analysis was carried out after embedding the roots in agar containing bromocresol purple as pH indicator. Efficient cultivar 'Brown Raya' showed greater decrease in pH than P-inefficient 'B.S.A' in the culture media. Hydroponically grown cultivars were compared with respect to P-utilization efficiency (PUE), P-stress factor (PSF), and Ca- and P-uptake at P-starvation. PUE, and Ca- and P-uptake correlated significantly (P<0.01) with biomass accumulation, indicating that higher P-uptake of efficient cultivars was because of their higher Ca-uptake, which in turn was related to their better P-acquisition and PUE. Remodelling of root architecture of efficient cultivars helped the cultivars to establish a better rooting system, which provided basis for tolerance under P-starvation.
Keywords Brassica Bromocresol purple H(+) -efflux Rhizospheirc pH changes and acidification PUE
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 107
End Page 117
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313432
JaLCDOI 10.18926/fest/11450
FullText URL 012_099_106.pdf
Author Akhtar M. Shahbaz| Oki, Yoko| Adachi, Tadashi| Khan Md. H. R|
Abstract As a rule, ion uptake by plant cells and roots has features of saturation kinetics. This is in accordance with the assumption of control, as for example by the number of binding sites of ions (carriers, permeases), or the capacity of the proton efflux pumps, in the plasma membrane and tonoplast. Solute transport across membranes is carrier mediated transport. Protein macromolecules integrated into the membrane matrix seems to be the carriers. The carrier-mediated process is subject to kinetics assumig that the number of carriers (binding sites) in the membranes is limited. Kinetics of ion transport through a membrane is considered equivalent to relationship between an enzyme and its substrate. To obtain plants of different P status, two genetically diverse Brassica cultivars (P-tolerant 'Con-1' and P-sensitive 'Gold Rush') were grown for several weeks in nutrient solution culture media. P-uptake kinetics of the roots with intact plants in short-term experiments by monitoring P depletion in culture media revealed that P-tolerant 'Con-1' cultivar had favorable characteristics for P-uptake because of high I(max) or V(max) and low K(m) or 1/2 I(max) value than P-sensitive 'Gold Rush' cultivar. By plotting relative growth rate (RGR) and internal P-concentration (PNC) among P-tolerant (group I; Brown Raya, Con-1, Rainbow, Dunkled and Peela Raya) and P-sensitive (group II; Toria, Sultan Raya, B.S.A, Toria Selection and Gold Rush) cultivars revealed that group I cultivars showed large metabolic fraction and small structural fraction than group II cultivars which provided basis for P-stress tolerance.
Keywords Brassica Membrane binding sites Carrier-mediated transport I(max) or V(max), K(m) Pi-uptake rate RGR
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 99
End Page 106
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002314027
JaLCDOI 10.18926/fest/11446
FullText URL 012_091_098.pdf
Author Akhtar M. Shahbaz| Oki, Yoko| Adachi, Tadashi| Khan Md. H. R.|
Abstract The potential of a crop favorably respond to breeding/selection and bioengineering programs depends upon the nature and magnitude of genetic variability. For effective selection, information on nature and magnitude of variation in population, association of character with dry matter yield and among themselves and the extent of environmental influence on the expression of these characters are necessary. The estimates of genetic parameters help in understanding the role of various plant traits in establishing the growth behavior of cultivars under a given set of environmental conditions. Genetic analysis leads us to a clear understanding of different morphological, physiological and genetic characters and also the type and extent of their contribution to dry matter yield. Six Brassica cultivars were grown in a P-deficient sandy loam soil for 49 days after sowing. Significant variations were observed for all the characters in all the cultivars used in the experiment. All the characters showed high heritability coupled with high genetic advance. Heritability (h(2)) is an approximate measure of the expression of a character. The highest estimates of broad sense heritability (h(2)= 0.90) and relative expected genetic advance (85.72%) were noted for root dry matter (RDM), while the estimate of expected genetic advance at 10% selection intensity was quite high (ΔG = 85.30c㎡) for leaf area per plant. The estimates of coheritability were positive and relatively higher for rootshoot ratio (RSR) in combination with shoot dry matter (SDM) (coh(2) = 2.002) and phosphorus use efficiency (PUE) (coh(2) = 1.875), whereas coheritability estimates were negative between leaf area per plant and RSR (coh(2) = -0.2010) indicating lack of association between these traits. High heritability with high genetic advance was exhibited by all the studied plant traits of cultivars evidencing that the traits could be further improved through individual plant selection. The innate variations within the Brassica gene-pool impel to drive a concentrated effort to understand the basis of adaptability. Access to the relevant genetic traits and information will provide necessary tools to select the optimal combinations of alleles adapted to local and changing growing environments especially nutrient stress conditions such as phosphorus (P) starvation.
Keywords Brassica Coheritability Genetic advance Genetic variability P-starvation Selection intensity
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 91
End Page 98
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313657
JaLCDOI 10.18926/fest/11443
FullText URL 012_083_089.pdf
Author Khan Md. H. R.| Rahman Md. K.| Rouf A. J. M. A.| Sattar G. S.| Akhtar M. S.| Oki, Yoko| Adachi, Tadashi|
Abstract The pH values in the profiles of unburnt (agricultural land) soils were found to increase as a function of soil depth and burning (400 to 1000℃) of the soils increased average pH by 8%. The average sand content of the burnt (soil around brick kilns) soil profiles was increased by 245%, while 39 and 36% decreased the silt and clay contents. Soil organic carbon (Corg) in the unburnt soils (0-20 cm) at different agro-ecological zones in the eastern region of Bangladesh ranged from 0.8 and 1.4%, whereas the content of microbial biomass carbon (Cmic) in the studied unburnt soils ranged between 5 and 7% of the total Corg, suggesting that the microbial biomass releasing considerable amounts of carbon in soil while burning of the soils drastically reduced this contribution to about 1%. The values of soil Cmic in the unburnt soils were approximately 2 to 6 times higher in the topsoils than the subsoils (20-60 cm). Variable rainfall, temperature and soil fertility had an overriding influence, which was reflected by the average minimum (276 μg g(-1)) and maximum (439) amounts of soil Cmic in Moulvibazar and Cox' Bazar sites. The Cmic decreased upon soil burning by 92% of its original average value (346 μg g(-1)) in the soil profile of up to 100 cm. Burning of topsoils strikingly increased the Corg/Cmic ratio by about 6 to 9 times, while reduced the C/N ratio by about 1.5 to 2.5 times. The average loss of Corg, available and total N due to burning of the soils were 66, 72 and 44% (increase over average content of unburnt soil: IOAC), respectively, which suggests that the burning of the soils offset the essential roles of soil microorganisms, reduced soil fertility and soil microbial contribution.
Keywords brick burning C/N ratio microbial biomass carbon soil organic carbon ratio of microbial biomass to organic carbon.
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 83
End Page 89
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313396
JaLCDOI 10.18926/fest/11441
FullText URL 012_077_081.pdf
Author Khan Md. H. R.| Mohiuddin M.| Rahman M.| Akhtar M. S.| Oki, Yoko| Adachi, Tadashi|
Abstract Studies on the existing non-symbiotic diazotrophic systems still are the most promising for better use of biological nitrogen fixation (BNF) in agriculture. The possibilities for the extension of nitrogen fixation to rice plants still speculative. The prospect of extension of N(2)-fixation to other plants was originally formulated to simulate the possibilities for the biological use of atmospheric nitrogen in order to overcome the ecological and economical problems of nitrogenous fertilizers. In view of this, the present study was conducted for the characterization and identification of N(2)-fixing bacterial strains at the maturity (110 days) stage in rhizosphere of rice (BR 10, Oryza sativa L.) grown in Brahmaputra Alluvium soil of Bangladesh. The soil is characterized as 'Inceptisol' order and 'Aquept' suborder. It was identified as 'Dhamrai series', had 'silt' texture, pH 6.0 and 6.8 C/N ratio. The present results of the microbial tests on the rice rhizosphere soil demonstrated that out of 401 isolates, only 94 were branded as nitrogen fixing organisms per gram of soil, which is about 23.4% of the total isolates. Based on the selection criteria, four individual strains were selected for identification. Biochemical tests were conducted for proper identification. They were identified as Closteridium spp., Klebsiella spp., Bacillus spp. and Azospirllum spp.
Keywords Azospirllum spp. Bacillus spp. BNF Closteridium spp. Diazotrophs Klebsiella spp. Oryza sativa L.
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 77
End Page 81
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313950
JaLCDOI 10.18926/fest/11439
FullText URL 012_071_076.pdf
Author Chen W.| Yoshida R.| Kawara, Osami|
Abstract The Asahi River Dam reservoir is one of the important fresh water resources in Okayama, Japan, and its eutrophication has been noted since the 1980s. Therefore, aeration has been applied to control the growth of phytoplankton. In this study, we discussed the effect of aeration and water-intake depth on the water quality distribution in the reservoir, based on numerical simulation and observation. The principal conclusions were as follows:(1) The numerical simulation models applied here reproduced observations fairly well. (2) Water intake from the surfacce layer reduced the concentration of chlorophyll a in the surface layers. Water intake from the middle or bottom layer improved the deficit of dissolved oxygen in the bottom layers. (3) Aeration together with water intake from the middle or bottom layer improved the deficit of dissolved oxygen in the bottom layers.
Keywords the Asahi River Dam Reservoir numerical simulation eutrophication water intake depth dissolved oxygen chlorophylla
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 71
End Page 76
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002314056
JaLCDOI 10.18926/fest/11436
FullText URL 012_063_070.pdf
Author Saif Eideen S. A.| Taniguchi, Takeo|
Abstract The homogenization method is used to model steel fiber reinforced concrete SFRC by converting the random distribution of fibers to a periodic one. The periodic distribution is chosen to hold similar properties of the composite material in both perpendicular directions to represent an average approximation for the random distribution. The material is modeled as a composite with brittle matrix and elastic fibers. Two patterns of the unit cell are examined to establish the homogenized stiffiness matrix in elastic and plastic stages. A rigid plastic bonding is considered between matrix and fibers. The smeared crack model is used to represent the nonlinearity of concrete. The validity of the homogenized model is examined by comparing the numerical results with the experimental results. The results show good agreement with the experimental work when a suitable pattern of the unit cell is used.
Keywords fiber reinforced concrete composite materials homogenization periodicity finite element
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 63
End Page 70
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313536
JaLCDOI 10.18926/fest/11434
FullText URL 012_051_061.pdf
Author Liu Xianbing| Tanaka, Masaru| Matsui, Yasuhiro|
Abstract Serious adverse impacts on the environment and human health from the recycling and disposal of electronic waste have occurred in the past and continue to occur in China today, due to the lack of a national management strategy. With aiming to support the management strategy development, a study was carried out to plan and quantitatively evaluate the optional management frameworks for the selected five main types of large electronic home appliances in Beijing, the capital city and a typically big municipality in China. This paper outlined the main findings yielded from the series of assessment studies which started from the generation amount prediction and material flow analysis of the used electronic appliances, planning and optimization of the collection & transportation frameworks and ended at the economic evaluation of the optional recycling processes for the waste appliances. Although the revenue could be expected from the result of isolated evaluation of the recycling processes, the entire system will be economically unavailable if the used appliances are still collected from the owners at current prices. The traditional understanding of householders on the values of their used appliances should be changed in Beijing and China as a whole. Establishment of a formal collection system that could take back the used appliances at lower prices (less than 40% of the current level) is the key for the construction of a formal management framework with sustainability.
Keywords Waste electronic home appliances Management framework Assessment Beijing China
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 51
End Page 61
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313493
JaLCDOI 10.18926/fest/11432
FullText URL 012_041_049.pdf
Author Chaerul Mochammad| Tanaka, Masaru| V. Shekdar Ashok|
Abstract In Indonesia, municipal solid waste (MSW) is becoming increasing complex due to variety of reasons like the increasing quantity of MSW, rising public awareness and municipal administration policies in different cities and surrounding regencies. After the landslide accident at Bandung city disposal site, most of related agencies are trying their level best to improve the situation. Against this backdrop, this paper attempts to analyze the present system of MSW addressing variety of aspects such as quantity and composition of MSW being generated, operational management, legal system as well as financial aspect. The systematic assessment has revealed the problem like lack of legal framework, low coverage, improper waste storage, less encouragement for composting, and lack of proper disposal practices. Finally, an action plan is presenting suggestion for immediate and future addressing the issues like the operational management, institutional, financial aspect, public participation & environmental education.
Keywords municipal solid waste strategic actions Indonesia
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 41
End Page 49
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313633
JaLCDOI 10.18926/fest/11429
Title Alternative Variable selection besed on global score estimation and its numerical investigation
FullText URL 012_029_040.pdf
Author Mori, Yuichi| Fueda, Kaoru| Iizuka, Masaya|
Abstract A variable selection method using global score estimation is proposed, which is applicable as a selection criterion in any multivariate method without external variables such as principal component analysis. This method selects a reasonable subset of variables so that the global scores, e.g. principal component scores, which are computed based on the selected variables, approximate the original global scores as well as possible in the context of the least squares. Three computational steps are proposed to estimate the scores according to how to satisfy the restriction that the estimated global scores are mutually uncorrelated. Three different examples are analyzed to demonstrate the performance and usefulness of the proposed method numerically, in which three steps are evaluated and the results obtained using four cost-saving selection procedures are compared.
Keywords principal components least square orthogonalization cost-saving selection
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 29
End Page 40
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313992
JaLCDOI 10.18926/fest/11425
Title Alternative A mathematical model of Plasmodium falciparum transmission incorporating drug resistance: Simulations of the Solomon Islands situation
FullText URL 012_019_027.pdf
Author Chen, Tiantian| Nishina, Tomohiko| Hisakane, Naoto| Ishikawa, Hirofumi|
Abstract The Solomon Islands are known as a high endemic region of malaria. The resistance of Plasmodium falciparum to chloroquine has been confirmed since 1980 in the Solomon Islands, and the spread of chloroquine resistance is a big hurdle to malaria control. We have constructured the model for P. falciparum making allowance of chloroquine resistance. We distinguish the infection of resistance strains from that of sensitive strains in both the human and the vector populations. Since the overall parasite rate and the parasite rate of gametocytes for P. falciparum are strongly dependent on age, the human population is divided into 7 age groups in the model. The epidemiological parameters are determined by malariological survey in northeastern Guadalcanal (Ishii et al.) and the sporozoite rate in vector population is assumed as 0.1% based on the entomological study (Harada et al.) Our study aims at estimating the effect of mass drug administration under the presence of drug-resistance and also analyzing the escalation of drug-resistance through the transmission model for P. falciparum which can deal with chloroquine resistance.
Keywords Solomon Islands Plasmodium falciparum drug resistance model
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 19
End Page 27
ISSN 1341-9099
language 日本語
File Version publisher
NAID 120002313858
JaLCDOI 10.18926/fest/11423
FullText URL 012_007_018.pdf
Author Imura Keigo| XiaoDong Wang| Ishikawa, Hirofumi|
Abstract The elliptic curve cryptosystem is a popular cryptosystem. Its safety depends on the difficulty of the elliptic curve discrete logarithm problem (ECDLP). From the viewpoint of ECDLP, it is very interesting to determine the order of elliptic curves. We tabulate the order of elliptic curves on the finite field of characteristic two using the Schoof algorithm, which is an efficient algorithm to decide orders. The Schoof algorithm is carried out by O(log(8)q). Because the calculation of y(q2) occupies most of the time used to execute the Schoof algorithm, it is necessary to reduce the amount of y(q2) calculations.
Keywords elliptic curve order division polynomial Schoof algorithm finite field of characteristic two
Publication Title 岡山大学環境理工学部研究報告
Published Date 2007-03-15
Volume volume12
Issue issue1
Start Page 7
End Page 18
ISSN 1341-9099
language 英語
File Version publisher
NAID 120002313838