Effect of compaction pressure on consolidation behaviour of unsaturated silty soil

The effect of compaction pressure on subsequent soil behaviour during isotropic consolidation has been investigated by conducting controlled-suction triaxial tests on samples of an unsaturated compacted silty soil. A comprehensive set of laboratory experiments was carried out in a double-walled triaxial apparatus on samples of unsaturated soil that were prepared using two different compaction pressures. The axis translation technique was used for creating the desired suctions in the samples. In the experiments, the soil samples were subjected to isotropic consolidation under constant suctions. The results show that different compaction pressures produce different fabrics in a soil and therefore affect the behaviour of the soil. The results also show that the value of yield stress and the location of the loading¿collapse (LC) yield curve are functions of soil fabric. Furthermore, it is shown that the slopes of normal consolidation lines for densely and loosely compacted samples differ in unsaturated conditions but are the same in saturated soils. A comparison is made between the behaviour of the dense and loose samples, and the difference in the behaviour is explained

Facet modulation selective epitaxy–a technique for quantum-well wire doublet fabrication

The technique of facet modulation selective epitaxy and its application to quantum-well wire doublet fabrication are described. Successful fabrication of wire doublets in the AlxGa1–xAs material system is achieved. The smallest wire fabricated has a crescent cross section less than 140 Å thick and less than 1400 Å wide. Backscattered electron images, transmission electron micrographs, cathodoluminescence spectra, and spectrally resolved cathodoluminescence images of the wire doublets are presented

Improving an Organization Declining Performance

PT Nusantara Turbin dan Propulsi (NTP) is one of trusted excellence center leading in South East Asia in the field of engineering, maintenance, repair and overhaul of gas turbines and rotating equipment. PT NTP has two strategic business units, namely Aero Engine Services and Industrial Turbine Services. PT NTP facing a problem in achieving the target in terms of revenue and timeliness of project completion that led to customer dissatisfaction and also there is geopolitical issue that affects the company financial performance. Those problems are the overcome challenges of the company in the future. In accordance with those problems, this final project will discuss improvements an organization declining performance. Two methods were used to find out problem that occurred at NTP, first is quantitative; by distributed questionnaires among fulltime employees, and second is qualitative; by conduted interviews with managers and employees. Questionnaires spread to Managers, Supervisor, and Staffs were aims to analyze level of organization, groups, and individual. Organization criteria (by Mckinsey) are strategy, structure, system, skill, staff, style, and shared values. Group (by Thomas Cummings and Cristopher Worley) are task structure, group composition, team functioning, and group norms. Individual (by McShane and Von Glinow) motivation, ability, role of perception, and situational factors. To improve an organization declining performance, organization can be diagnosed at three different levels, namely individual level, group level, and organizational level. Those three levels are the main factor to improve an organization declining performance. Based on this analysis, it can be determined the level of organization that led to a declining performance of organization. The result of the analysis of the information obtained from PT NTP concluded that the level of organizational is the causes of the organization declining performance. The analysis that conducted is by improving the elements that derived from the Mckinsey 7-S framework, namely strategy, system, structure, skill, staff, style, and shared values. The implementation plan of those improvements is applied using the eight-step model of change from John P. Kotter. Keywords: Organization declining performance, organizational level, Mckinsey 7-S framewor

Effect of recent flood on ichthyoplankton and juvenile fish assemblage changes in Kuantan River revealed through DNA barcoding

Identifying early life stages of fishes to the species level is one of the challenging task for the taxonomist as the information on key morphological characters are overlapping between genetically closer individuals. Universal DNA barcode (cytochrome oxidase C subunit 1) gene sequence helped tremendously in species level identification of early life stages of fishes. This study was aimed to address the effect of recent monsoon on assemblage changes in Ichthyoplankton and juvenile fishes of Kuantan river, Whereby, the samples were identified to the species level using COX1 gene sequencing. Samples were collected using modified bubu light trap net between April 2015 and December 2015 in Kuantan river and its all tributaries. Fish larvae/juvenile size ranged from 3mm to 100mm, with most abundant individual belong to size class <10mm. A total of 28 species belong to 15 families were successfully identified to the species level from the total of 58 barcodes generated from 372 larval/juvenile samples collected. Unlike the previous study, significant shift in species assemblage has been recorded in this study. Statistical analysis showed significant effect of salinity and suspended particulate on the species distribution and abundance. The dominant fishes belong to the cyprinidae family followed by toxotidae, ambasidae and eleotridae compared to the previous study (Ariidae, Lactaridae and Lutjanidae). It could be concluded that the recent flood (mid-December 2014 to January 2015) in east peninsular Malaysia will have greater positive impact on Kuantan river fish diversity in near future

Feeding ecology and food preferences of carcinoscorpius rotundicauda collected from the Pahang nesting grounds

The first time report on the feeding ecology and food preference of mangrove horseshoe crab Carcinoscorpius rotundicauda (Latreille 1802) at their nesting grounds along the Pahang coast is given. Monthly sampling was carried out between March 2010 and February 2011 covering both monsoonal (March to October) and non-monsoonal (November to February) seasons. Major macrobenthic gut contents (bivalves, gastropods, crustaceans, polychaetes and miscellaneous food items including plant materials) were identified using microscopic examination. An electivity index (E1) was calculated for the frequent food items observed in the gut region of C. rotundicauda during monsoon and non-monsoon seasons. The EI was negative for crustaceans and positive for all the other food items including bivalves, gastropods, polychaetes and miscellaneous food items (which include insects, amphipods, Isopods, larval and juvenile stages of fishes, foraminifera and other Annelid worms). It is interesting to note that C. rotundicauda prefered less number of bivalves than polychaetes during non monsoon seasons but it was the reverse during monsoonal period. Male crabs intensely preyed on gastropods and female prefers polychaete worms during the peak mating/nesting season (June - August 2010). Seasonal variations in food composition showed that mollusks formed the main item especially gastropods. Unidentified organic matters in the gut content analysis of C. rotundicauda showed high preference towards plant materials. Gastro Somatic Index (GaSI) analysis showed that the feeding intensity of male crabs was higher during non-monsoon period while it was higher during monsoonal period in female crabs. In conclusion, the feeding ecology of mangrove horseshoe crabs were more similar to its closer and distant conspecifics. However, it was postulated that the higher preference of polychaete worms by the female C. rotundicauda during the peak mating season indicated its role in regulating the nesting behaviour

Macrobenthic community at nesting grounds of horseshoe crabs (Tachypleus gigas and Carcinoscorpius rotundicauda) at Pahang Coast, Malaysia

Macrobenthos consists of the organisms that live at the bottom of the water column and are visible to the naked eye (usually >0.5mm in size) 2.About 80% of the benthic organisms are Epifauna that are living on or are attached to the surface of rocky areas or firm sediments play an important role in ecosystem processes such as nutrient cycling, pollutant metabolism, dispersion and burial, and in secondary production 3.Macro invertebrate species offers a spectrum of responses to environmental stresses and a broad range of responses to different pollutants 4.The food preferences of horseshoe crabs are well studied from the wild environment while the similar studies are still scanty along their nesting groun

Impact of stress on excretion in earthworm (Perionyxexcavatus)

In the present study, the nature of excretory products and the impact of stress on the rate of excretion of the megascolecid earthworm, Perionyx excavatus was studied. Excretion in P. excavatus was analyzed with reference to three aqueous media: tap water, distilled water and 1% Sodium chloride. Clitellate worms (N=5.) were taken for the study and nitrogenous products (ammonia and urea) eliminated in the three media were analyzed for twenty four hours, sampling was carried out at an interval of two hours. In order to assess immediate response in the first one hour, samples were also taken at the end of 30 minutes, 45 minutes and 60 minutes, during the first one hour of observation. After 60 minutes, the worms excreted 0.023 mg ammonia and 1.451 mg urea in the tap water; 0.014 mg ammonia and 1.397 urea in distilled water; and 0.030 and 1.076 mg ammonia and urea in 1% NaCl. After 60 minutes, under heat stress, the worms excreted 0.011 mg ammonia and 0.578 Urea in the tap water; 0.006 mg ammonia and 0.682 mg urea in the distilled water; 0.009 mg ammonia and 0.520 urea in the 1% NaCl solution. Animals exposed to H2 SO4 stress, excreted 0.034 mg ammonia and 1.023 mg urea in the tap water; 0.040 mg ammonia and 0.645 mg ammonia and 0.620 mg urea in the 1 % NaCl solution. The worm survived 24 hours in the tap water excreting ammonia urea in the distilled water; 0.03 mg (0.188 mg) and urea (0.926 mg) and the latter at higher amount indicating that P. excavatus is primarily ureotelic and also capable of excreting ammonia. The worm did not survive beyond eight hours in the distilled water and 1% NaCl. The present study clearly demonstrates that the earthworm P. excavatus is primarily ureotelic and revert to ammonotelism under stress situation

Accumulation and distribution of lead and copper in avicennia marina and rhizophora apiculatafrom Balok Mangrove Forest, Pahang, Malaysia

Bioaccumulation of lead and Copper in Avicennia marina and Rhizophora apiculata was studied. Samples of leaves, barks and roots were collected from Balok mangrove forest, Pahang. Pb and Cu accumulation was higher in Avicennia marina root tissue compared to bark and leaf but lower than surrounding sediment level. The average concentration of Pb in A. marina leaf, bark, root and sediment was observed to be 5.39 ppm, 3.63 ppm, 18.21 ppm and 23.13 ppm, and average Cu concentration was 4.13 ppm, 4.27 ppm, 4.81 ppm and 12.33 ppm, respectively. R. apiculata also showed higher concentration of Pb and Cu in root tissue compared to bark and leaf tissues but lower than surrounding sediment. The average concentration of Pb in R. apiculata leaf, bark, root and sediment was observed to be 4.30 ppm, 2.97 ppm, 22.45 ppm and 31.23 ppm, respectively. The average Cu concentration was 2.93 ppm, 4.71 ppm, 4.81 ppm and 15.52 ppm, respectively. Results of concentration factors (CF) showed that the accumulation of Pb and Cu was higher in A. marina than in R. apiculata

Health Aware Stochastic Planning For Persistent Package Delivery Missions Using Quadrotors

In persistent missions, taking system’s health and capability degradation into account is an essential factor to predict and avoid failures. The state space in health-aware planning problems is often a mixture of continuous vehicle-level and discrete mission-level states. This in particular poses a challenge when the mission domain is partially observable and restricts the use of computationally expensive forward search methods. This paper presents a method that exploits a structure that exists in many health-aware planning problems and performs a two-layer planning scheme. The lower layer exploits the local linearization and Gaussian distribution assumption over vehicle-level states while the higher layer maintains a non-Gaussian distribution over discrete mission-level variables. This two-layer planning scheme allows us to limit the expensive online forward search to the mission-level states, and thus predict system’s behavior over longer horizons in the future. We demonstrate the performance of the method on a long duration package delivery mission using a quadrotor in a partially-observable domain in the presence of constraints and health/capability degradation