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Verifying that logic control satisfies some desirable properties is essential to the proper and safe functioning of a manufacturing system. Input order robustness is one such property that has not been thoroughly explored. If a logic controller is input order robust for all sets of inputs whose elements can arrive in any order and whose order should not affect the logic controller's final state or set of outputs, then the logic controller behaves the same in these regards irrespective of the inputs' order. This paper develops a procedure to verify input order robustness for logic controllers implemented in a variety of formalisms, and demonstrates its application on Event-Condition-Action Modular Finite-State Machines (ECA MFSM) and IEC 61499 controllers. Additionally, this verification is extended to a class of networks of controllers, and the computational complexity of such verifications are discussed.

In recent years, many pastoral farmers in New Zealand reduced or withheld phosphorus (P) fertilizer application to their pasture in response to rising fertilizer costs and falling prices in farm produce. When P fertilizer application is withheld, pasture and animal production relies on the P reserves accumulated in the soil from the previous P fertilizer applications. A field‐plot experiment superimposed on irrigated pastures that had received long‐term annual superphosphate (SP) fertilizer applications for 25 years was conducted to examine the forms of P accumulated from the previous SP applications contributing to plant‐available P. The long‐term SP applications were withheld, and the soil was subjected to treatments of no fertilizer (nil), P only, sulphur (S) only, or both P and S, each with P and S at two rates in a split‐plot design with four replicates that ran for 6 years. Soil samples (0–75 mm deep) collected from the trial each year were subjected to a sequential P fractionation scheme....

The popular and widely used 15nitrogen (N)–isotope dilution method for estimating biological N fixation (BNF) of pasture and tree legumes relies largely on the ability to overcome the principal source of error due to the problem of selecting appropriate reference plants. A field experiment was conducted to evaluate the suitability of 12 non‐N2‐fixing plants (i.e., nonlegumes) as reference plants for estimating the BNF of three pasture legumes (white clover, Trifolium repens L.; lucerne, Medicago sativa; and red clover, Trifolium pratense L.) in standard ryegrass–white clover (RWC) and multispecies pastures (MSP) under dry‐land and irrigation systems, over four seasons in Canterbury, New Zealand. The 15N‐isotope dilution method involving field 15N‐microplots was used to estimate BNF. Non‐N2‐fixing plants were used either singly or in combination as reference plants to estimate the BNF of the three legumes. Results obtained showed that, on the whole, 15N‐enrichment values of legumes and nonlegumes ...

In this paper, the methods to rapidly deploy closed-loop control systems are presented. A flexible real-time embedded platform based on reconfigurable computing technologies is established, on which control blocks consisting of optimized control algorithms are set up. By employing control blocks, a set of tools aiming to shorten the development cycle of embedded control systems are developed. Compare to conventional ways, the tools give controller developers much faster ways to construct required controllers with higher flexibility.

In grassed-down fruit orchards, understorey plant residues have been shown to constitute an important source of soil organic matter and plant nutrients in biological and integrated fruit production systems. Under these systems, contrasting understorey plant residue types and different orchard treeline management practices may affect the decomposition rates and nutrient release from these residues. Although a recent field study has found these factors to be important, their detailed comparisons have not been conducted. In the present study, two incubation experiments were conducted concurrently in the laboratory at 25°C for 110 days. Experiment I examined the relationships between residue quality characteristics and decomposition rates of a range of six organic residues and three understorey plant residues from biological and integrated fruit orchard systems. A control treatment without added residue was also studied. All residues were analyzed for important biochemical quality factors. Experiment...

Although amounts and patterns of nitrogen mineralization from decomposing crop residues and other organic materials are known to be affected by their initial chemical composition and quality (e.g., C/N ratio, lignin and soluble polyphenol concentrations), published results differed in which properties correlated best with the N release. Six crop residues (leguminous and non-leguminous) and two organic materials (spent mushroom compost and dairy pond sludge) were incubated to determine the release of mineral N and its relationships to residue chemical composition. A previously proposed equation for calculating plant residue quality index (PRQI) was modified to PRQIM (Plant residue quality index-modified) to include C/N, lignin/N and polyphenol/N ratios of crop residues and organic materials so as to integrate these three major variables, which control the residue decomposition and nutrient release. The PRQIM was significantly and highly correlated with N release not only for the data obtained in the present study but also for three independent data sets obtained from the literature for a wide variety of organic materials ranging from arable crop residues, tropical savanna woodland litter and leguminous tree prunings.

Although considerable progress has been made in relating extractable soil S to plant S availability, most of these studies determined the extractable soil S at the beginning of the experiment to use as an index of soil S status. This bears little or no relationship to the S taken up by plants during the entire growing season. The present study investigates the changes in extractable soil S with time and relates these to changes in plant S uptake. Six soils with different long-term fertiliser histories (0, 21, 42 kg of S as superphosphate ha−1 applied since 1952) and animal camping treatments (camp and non-camp) were used in two pot systems (with and without plants). Carrier-free 35SO4–S was added to the soils, to provide the information on the transformations of recently added S between the different extractable S forms in soils and whether these transformations could predict plant-available S. The soils were pre-conditioned and then transferred to the glasshouse, where one set of pots were planted with perennial ryegrass (Lolium perenne L.) while the other set was left uncropped. Periodic plant harvests and soil samplings at four weekly intervals were conducted over a period of 20 weeks to determine plant S uptake and amounts of extractable soil S and 35S forms using five extractants. Same extractions of soil S and 35S were conducted for the initial soils. Results showed that HI-reducible and total soil S extracted by CaCl2, KH2PO4 and by KCl at 40 °C were utilised significantly by plants but not those extracted by NaHCO3 and NaOH extractants. However, after the 8th week, plants continued to take up S even though levels of S extracted from the soil by CaCl2, KH2PO4 and by KCl at 40 °C remained low and unchanged. These results suggest that soil S taken up by plants after the 8th week period originated directly from the mineralisation of soil organic S from S pools other than those present in the extractable soil S forms. Similar results were shown by 35S data, thereby confirming the complexity of determining plant S availability based on soil S extraction methods.

S mineralization in soils with different fertilizer histories [0, 188 and 376 kg superphosphate (SP) ha/year applied since 1952] and animal camping treatments (camp and non-camp soils) was determined simultaneously under the same glasshouse conditions using three different methods (i.e. open incubation, pots with and without plants). Results obtained showed that amounts and patterns of soil S mineralized differed from one system to the other. In the open incubation system, the pattern of S mineralization showed a rapid release of S in the first 4 weeks followed by no substantial release during the remaining 20 weeks of incubation. In both pot systems, S mineralization was slow initially and increased significantly with time. Total amounts of 32S mineralized in the open incubation system ranged from 7.5 to 11.9 µg S/g soil, while corresponding values for pot systems were 2.3–3.7 and 2.3–5.9 µg S/g soil for pots with and without plants, respectively. Rates of soil 32S mineralization with time as fitted by regression models were different in the three systems, showing the differential impact of leaching, crop removal and plant effects on soil S mineralization. Similar results were obtained using radioactive 35S tracer. Overall, the results suggested that contrary to commonly postulated ideas, soil S mineralization determined by periodic leaching of soil in the open incubation system does not simulate crop removal of S or provide a means of predicting plant S availability.

It is generally recognized that in order for arable farming systems to remain sustainable in the long term, they need to be productive and their soil fertility must be maintained to continue to provide viable yields with minimum detrimental effects on soil and environmental quality. The use of biological nitrogen fixation (BNF) as the main source of nitrogen (N) for crops is an important sustainable management strategy. Amounts of BNF in four pairs of conventional and organic mixed cropping farms, each with three stages of pasture establishment in Canterbury, New Zealand were compared under farmers' field conditions over a period of one year using the 15N isotope dilution technique. Composite topsoil (0–75 mm) samples were taken from all sites at the beginning and end of the trials. These were analyzed for soil pH and available nutrients according to New Zealand “MAF Quick Test” methods. In addition, at the end of the trials, soil samples at four depths (0–50, 50–100, 100–150, 150–200 mm) were taken from ...

In this paper, an efficient micromachining process, which combines micro electro discharge machining (MEDM) with ultrasonic vibration, is proposed to improve the surface roughness of micromould inserts. The introduction of ultrasound is aimed at improving the surface quality by means of the accelerated expulsion of debris out of the small gap between the electrode and the workpiece. Experimental results show that the surface roughness of the machined workpiece is improved.

Major objectives of this study were to evaluate the effects of organic, conventional and integrated orchard fruit production systems on the quality and quantity of soil organic matter in orchard floors and to identify sensitive soil organic matter indicators. Seventeen different soil organic matter parameters were studied. These were soil aggregate stability (AS), total nitrogen (TN), total carbon (TC). carbon/nitrogen ratio, rnicrobial biomass N (BN), microbial biomass C (BC), BC:BN; BC:TC; BN:TN; hot-water extractable C (HC), hot-water extractable carbohydrate (HCA), HCA:HC: humin N (hum N), humin C (hum C), hum C:TC: hum N:TN and potentially mineralizable N (Pot N). They were based largely on soil organic matter characteristics and fractions extracted sequentially by different extractants from soils collected from the alleys and treelines of organic, conventional, and integrated grassed-down apple orchard types from both commercial and experimental sites in Canterbury, New Zealand A total of 12 apple orchards were investigated. Soil samples collected from these orchards (0-75 mm depth) were analysed for TC. TN. BC. BN, Pot N. AS and also sequentially extracted for labile and stable soil organic matter fractions using cold and hot water, acid mixtures (hydrochlorie:hydroflouric acids, HC1:HF) and alkalis (sodium pyrophosphate and sodium hydroxide. Na 4 P 2 O 7 and NaOH). Only TN. BN, and BN:TN showed significant interaction effects and all these were associated with soil N. Overall, combining orchards according to similar management systems, results obtained showed no significant differences between experimental and commercial orchards. However, sensitive indicators capable of distinguishing significant differences between different orchard management systems were BC, BC:TC and HCA:HC while HCA:HC distinguished significantly between treelines and alleys within each group of the same orchard type.

Effects of cropping systems on soil organic matter (SOM) in a pair of conventional and biodynamic mixed cropping farms were investigated. Soil samples (0–75 and 75–150-mm depths) were analysed for total carbon (TC), total nitrogen (TN), microbial biomass C (BC) and microbial biomass N (BN), and sequentially extracted for labile and stable SOM using cold water, hot water, acid mixtures and alkalis. In the biodynamic farm, TC and TN decreased with increasing period of cropping but the reverse occurred under pastures. These were not shown in soils from the conventional farm, probably due to N fertilizer additions. Under pastures, increases in SOM were attributed to greater biological N2 fixation and the return of plant residues and excreta from grazing animals. Overall, sensitive SOM quality indicators found for labile SOM were BN, BN:TN and HC:TC, and for stable SOM were HCl/HFC, HCl/HFC:TC, humin C, humin N, humin C:TC and humin N:TN. The BN and BN:TN were better indicators than BC and BC:TC. The humin fraction was strongly related to both labile and stable SOM fractions suggesting that humin contained non-extractable strongly complexed SOM components with mineral matter and also non-extractable plant and microbial residual components.

In a previous study, the understorey biomass production and biological nitrogen (N) fixation of a grassed‐down organic apple orchard were presented. The aim of this paper is to report the results of a similar study of two conventional orchards in a nearby location and to compare the present results with those of the organic orchard. Biological N2 fixation was determined in the field using the 15N isotopic dilution technique and the experiments were conducted over a two‐year period. Present results showed that substantial amounts of N (112 to 143 kg N ha‐1.2 years‐1) were fixed in the understorey of the conventional orchard and these were not significantly different from those of the organic orchard. However, the N2 fixation was sustained in the conventional, but not in the organic orchards in the second year, probably due to regular additions of fertilizers in the conventional orchards. In both orchards, N2 fixation was better correlated with clover than total dry matter yield. Seasonal effects f...

Quantitative field measurements of biological nitrogen fixation (BNF) and biomass production by four different understorey pastures in a Pinus radiata-pasture agroforestry system were determined over a period of one year. The trees were two years old at the beginning of this study and the understorey pastures were being cut and removed for silage. The BNF was determined using the 15N dilution technique. Pastures of ryegrass+clover, cocksfoot+clover, phalaris+clover and lucerne were used. Substantial amounts of BNF were found (71 to 230 kg N ha−1 year−1) with lucerne showing the highest N fixation. However, lucerne derived only 71 to 72% of its N from the atmosphere (%Ndfa) during the spring/summer period compared to 83–97% with clovers, thus the net N demand from the soil was substantially higher with lucerne. This caused increased N stress to the trees. Clover in ryegrass+clover pasture fixed more N than the other grass+clover pastures. Although pasture position in relation to trees did not affect annual pasture total DMY and %Ndfa, pastures north of tree row grew better than those in other positions. Trees significantly affected the BNF of legumes and the botanical composition of pastures with highest BNF and legume production occurring in pastures midway between two rows of trees. These results suggest that it would be advantageous to evaluate different legumes and grasses for tolerance of shade and moisture stress in future studies. As the trees studied were only 1.5 to 3 m in height, their effects on BNF, seasonal pasture biomass production and botanical composition are expected to increase with tree dominance in the ecosystem with time. Amounts of N fixed were related to the productivity (i.e. dry matter and N yield) and seasonal persistence of the legumes. The productivity was high in spring and summer and low in autumn and winter.

One of the basic requirements for sustainable management of soils is to ensure that soil fertility is maintained in a productive state and conditions so as to enable the soil to continue to provide viable economic yields with minimum degradation of soil quality and quantity. The practice of supplying nitrogen to fruit trees from biological nitrogen fixation by pasture legumes in the understorey vegetation of orchards is a sustainable means of maintaining soil fertility. Quantitative field measurements of amounts of biomass production and biological nitrogen fixation by three different kinds of understorey vegetation in an organic apple orchard in Canterbury, New Zealand was conducted over a period of two years. Results obtained showed that understorey herbage biomass production varied from 8 to 12 t ha‐1 and biological nitrogen fixation varied from 118 to 126 kg N ha‐1 over the period of two years. Nitrogen fixation was significantly correlated with clover dry matter production. Results were affe...

Summary Changes in quantity and composition of soil organic matter (SOM) in pasture receiving annual superphosphate (SP) applications for 41 years at 0 (control), 188 and 376 kg SP ha−1a−1 were investigated in soil samples collected from 0–75 and 75–150 mm depths by determining total carbon (TC), total nitrogen (TN), biomass C (BC), biomass N (BN) and subjecting the soils to sequential extraction using cold water, hot water, a mixture of hydrochloric (0.1 M HC1) and hydrofluoric (0.3 M HF) acids (HCl/HF), and sodium pyrophosphate (Na4P2O7) followed by sodium hydroxide (NaOH) for extracting labile and stable SOM fractions. There were significant differences in some SOM fractions between control (0) and SP treatments (188 and 376), especially in the topsoil (0–75 mm) but these were not observed between the two SP treatments. Soil TN (0–75 mm), BN and BN: TN ratio (0–75 and 75–150 mm depths) and the proportion of hot–water–extractable C (HC) in soil TC (HC:TC) (0–75 mm) were significantly greater in the SP treatments than in the control. HC1/HF extractable C and the proportions of soil TC as HC1/HF extractable C (HC1/HF extractable C: TC) were smaller in the topsoil of SP treatments than in the control. Similar results were observed in humin N: TN ratio and the proportions of soil TC as cold–water–extractable carbohydrate (CWcC: TC) and of soil HC as hot–water–extractable carbohydrate (HWcC : HC). Increases in the proportion of labile fraction in SOM were reflected in values of BN, BC: BN, BN: TN, HWcC : HC and HC: TC whereas decreases in the proportion of stable fraction in SOM were found in humin N: TN and HCl/HF–extractable C: TC ratios. Increases in labile SOM (BN and N–containing compounds such as amino acids and amino sugars, which were extractable by hot water but were not present as carbohydrate) and decreases in stable SOM (HC1/ HF–extractable C and humin fraction) in soils under pastures treated with annual SP applications compared with the control were attributed to pasture improvement and the amelioration of P and S deficiency, resulting in a greater return of plant residues and animal excreta and also an increase in clover growth and associated biological N2 fixation. The additional labile SOM in SP treatments compared with that of the control was not associated with the soil mineral Al and Fe components.

Summary The reactions of two organic (citrate and fulvate) and two inorganic (chloride and phosphogypsum) calcium compounds were studied during leaching of columns of unsaturated acidic soil. The potential of these compounds to decrease the aluminium concentration in the soil solution and remove exchangeable aluminium, and their effects on soil acidity are described. The calcium citrate solution increased the soil solution pH from 5 to a maximum value of 7 in the upper portion of the column. In contrast, the fulvate, calcium chloride and phosphogypsum solutions had little effect on soil-solution pH. Treatment with calcium citrate, or fulvate solution that contained 51 mm Na, removed most of the exchangeable aluminium from the column. The cation exchange sites in the upper portion of the column were saturated with calcium, and the cation exchange capacity of the soil was increased from 35 to c. 80 mmolc kg−1 in the calcium citrate treatment. Leachate from this treatment contained low (< 2 mm) calcium concentrations and high aluminium concentrations. In contrast, the above changes were not shown by the calcium chloride and phosphogypsum treatments. In these treatments the calcium concentration in the leachate was equal to that in the inflowing solution, which indicated that calcium was transported through the entire column. These results suggest that calcium alone was ineffective in displacing aluminium from the cation exchange sites and a strong complexing agent such as citrate or fulvate is needed to mobilize the exchangeable aluminium.

Digital Signal Processing (DSP) is a modern digital technique for processing signals. Such digital manipulation technique is computationally intensive. Hence, DSPs are traditionally deployed on modern desktop computers, or on specialized processors called digital signal processors (DSPs). Development and verification of real-time DSP algorithm, on low-power battery-operated device, is a challenging task. The absence of an available real-time operating system on these devices further delays the development and design verification process. In this paper, a methodology to implement health monitoring DSP algorithms onto wireless sensor node (WSN) hardware is proposed. Firstly, a DSP pre-processing technique was investigated and identified for benchmarking. Secondly, a suitable DSP hardware platform for DSP deployment was investigated. Thirdly, a Real-Time (RT) Hardware-in-the-Loop (HIL) simulator system was developed to verify the DSP algorithm implementation. It is shown that the proposed methodology and RT HIL simulator system compliment each other; The RT HIL simulator system is the next best thing to a real testbed.

SUMMARYA field plot experiment of 271 days duration was conducted on New Zealand irrigated pastures, commencing in the summer (January) 1988, on a Templeton silt loam soil (Udic Ustochrept) by applying35sulphur (35S)-labelled urine (250 μCi/g S with 1300 μg S/ml) to field plots (600 × 600 mm) at a rate equivalent to that normally occurring in sheep urine patches (150 ml/0·03 m2) to investigate the distribution, transformations and recovery of urinary S in pasture soil–plant systems and sources of plant-available soil S as influenced by the available soil moisture at the time of urine application and varying amounts of applied irrigation water. Results obtained showed thatc.55–90% of35S-labelled urine was incorporated into soil sulphate (SO42−), ester SO42− and carbon (C)-bonded S fractions within the major plant rooting zone (0–300 mm), as early as 27 days after urine application. Hydriodic acid (Hl)-reducible and C-bonded soil S fractions showed no consistent trend of incorporation. On day 271, labelled-S was found in soil SO42−, Hl-reducible S and C-bonded S fractions to a soil depth of 500 mm, indicating that not only SO42− but also organic S fractions from soils and35S-labelled urine were leached beyond the major rooting zone. A large proportion (c.59–75%) of35S-labelled urine was not recovered in pasture soil–plant systems over a 271-day period, presumably due to leaching losses beyond the 0–300 mm soil depth. This estimated leaching loss was comparable to that (75%) predicted using the S model developed by the New Zealand Ministry of Agriculture. The recovery of urinary S in soil–plant systems over a 271-day period was not affected by different amounts of irrigation water applied 7 days after urine application to soil at either 50 or 75% available water holding capacity (AWHC). However, significantly lower S recovery occurred when urinary S was applied to the soil at 25% AWHC than at field capacity, suggesting that urinary S applied at field capacity might not have sufficient time to be adsorbed by soil particles, enter soil micropores or be immobilized by soil micro-organisms. Both soil ester SO42− and calcium phosphate-extractable soil S in urine-treated soils were found to be major S sources for pasture S uptake. Labelled S from35S-labelled urine accounted forc.12–47% of total S in pasture herbage.

In this paper, we investigate FPGA based wireless sensor node for distributed process monitoring. The research uses Collaborative Clusters of wireless sensor nodes concept to achieve distributed monitoring. To demonstrate the concept, a virtual chemical process unit in a typical chemical plant is used as an example application. The paper also presents the implementation of wireless sensor node with FPGA as the secondary processor. The sensor nodes will measure and pre-process raw data from sensor source before sending them to a higher order node in the network in order to achieve real-time monitoring. To enable the sensor nodes for rapid creation of wireless sensing applications, an improved system setup is proposed and the results of the implementation will be discussed.

Estimation of sulphur (S) fertiliser requirements in grazed pastures is crucial in sustaining pasture and animal production and in ensuring efficient use of S fertiliser resources in New Zealand. Different S cycling models have been developed worldwide to estimate pasture S requirements in grazed pastures. This review examined the S model developed in New Zealand by the Ministry of Agriculture and Fisheries (MAF) with the major aim of identifying limitations associated with and future research requirements for improving the applicability of this model. The review showed that the MAF S model incorporates most of the processes which contribute to S gains and losses from the S cycle under steady state conditions. However, S transfer rates within and between soil, plant, and animal S pools are not considered. The contribution of soil organic S to pasture plants is incorporated into this model by using the empirical pasture development index (PDI), the MAF soil sulphate (SO4 2-) “Quick test” (i.e., 0....

Although over 40% of excretal S is returned to intensively sheep ‐grazed pastures as faecal S, limited information is available on faecal S fractions, their water solubility and temporal distribution. This study reports results obtained from sheep faeces returned to grazed pastures which have received long‐term annual sulphate applications for 15–20 years. Five freshly‐voided sheep faecal samples ( 80%) faecal S fraction, regardless of faecal total S content or the time of year faecal samples were deposited. Faecal ester SO4 2‐ and inorganic _SO4 2‐fractions accounted for 3.3–7.1% and 0.1–1...

Failures of critical factory equipment are one of the main reasons for production stoppages and a regular maintenance schedule is required to ensure continuous operation of production line. However, regular maintenance can be both costly and inefficient. Vibrations are present in all machinery with moving parts and it had always been regarded as an indicator of the health and condition of rotating machinery. With advances in technology, what used to be a mechanic's hunch can now be measured and with reasonable accuracy. This paper present a proof-of-concept implementation of machine diagnostic on chip using an intelligent wireless sensor node, capable of processing and analyzing vibration signals from Micro-electromechanical (MEMS) sensors. Special design considerations were also made to allow the wireless sensor node to be reconfigurable and modular at both the hardware and software level. A custom fixed-point library was implemented to tackle accuracy issues in dealing with small numbers without the use of floating point numbers in resource scarce platforms.

Development of a work in progress (WIP) quality testing system is complex and requires significant effort in design, coding and integration the software with hardware components. On top of that, various regulations and testing procedures need to be observed during the testing. This paper presents a distributed control application platform (DCAP) to improve the development time and allow reusability. The platform includes building blocks, template libraries, best practices, and design patterns which can be easily deployed in various applications. A case study of developing a semiconductor WIP bond quality testing system was used to validate the platform together with an industrial partner. The result shows that a configurable, flexible and extensible WIP bond quality testing system can be developed using the platform in a shorter period of time. The WIP quality testing system can be configured to perform both destructive and non-destructive testing of wire bonding, ball bonding and die bonding by applying force to measure. The DCAP platform helps in providing the building blocks for manufacturing execution and control applications. The cross-platform nature with extensibility and flexibility features will help in various future industrial and research applications development.

This paper investigates the use of giant magneto resistive (GMR) sensor as a part of wireless sensor node to detect the vibrations of machines for equipment health monitoring purpose. In this study, a GMR sensor is connected through a signal conditioner to a wireless node. By exploiting the sensitivity of GMR sensors to near-field changes in magnetic flux, it is postulated that GMR sensor could detect vibration of a ferromagnetic structure without contact. The wireless GMR sensor node samples the signal of the sensor and transmits it wirelessly to a personal computer to display the frequency spectrum. Preliminary tests indicated that the sensor is able to detect the vibration of a 440-Hz tuning fork and the increase vibration due to imbalance of a rotor on a fault simulator. Vibration analysis is one way to observe the health condition of a machine. Moving parts of a machine generate vibrations, which can be observed in the frequency spectrum of approximately 10 Hz to S kHz. Faults of typical rotating machinery such as misalignment, imbalance and bearing wear out will produce increased amplitudes of vibration and exhibit frequency harmonics. As such, the condition of bearings and other moving components can be monitored. This study demonstrates the feasibility of using wireless GMR sensor node for detection of vibrations of a ferromagnetic structure.

Topsoils (0–75 mm) from four soil types with different sulphate retention capacities were collected from stock camp and non-camp (main grazing area) sites of grazed pastures in New Zealand which had been annually fertilized with superphosphate for more than 15 years. These soils were analysed for different S fractions and incubated at 30°C for 10 weeks using an open incubation technique in order to assess the extent of S mineralization and the release of soluble soil organic S from camp and non-camp soils during incubation. The soils were preleached with 0.01 M KCl, followed by 0.04 M Ca(H2PO4)2 before being incubated. Pre-incubation leachates and weekly 0.01 M KCl leachates were analysed for mineralized S (i.e., hydriodic acid-reducible S) and total S. Soluble organic S was estimated as the difference between these two S fractions. Results obtained show higher cumulative amounts of all three S fractions in leachates over a 10-week incubation period in camp than in non-camp soils, suggesting that higher mineralization occurred in camp soils. Cumulative amounts of mineralized S from camp and non-camp soils showed a linear relationship with duration of incubation (R 2≥0.985***), while the cumulative release of soluble organic S followed a quadratic relationship (R 2≥0.975***). A significant proportion (14.6%–40.8%) of total S release in KCl leachates was soluble organic S, indcating that organic S should be taken into account when assessing S mineralization. Mineralized S and soluble organic S were best correlated with 0.01 M CaCl2-extractable soil inorganic S (R 2=0.767***) and 0.04 M Ca(H2PO4)2-extractable soil inorganic S(R 2=0.823***), respectively. Soil sulphate retention capacity was found to influence amounts of mineralized S and soluble organic S, and thus periodic leaching with KCl to remove mineralized S from soils may not adequately reflect the extent of soil S mineralization in high sulphate-retentive soils. In low (

Topsoils (0–75 mm) from four different soil types were collected from stock camp and non-camp (main grazing area) areas of grazed pastures in New Zealand, which had been fertilised annually with superphosphate for more than 15 years, in order to assess the effects of grazing animals on the status and distribution of soil S fractions and organic matter. These soils were analysed for organic C, total N, total S, C-bonded S, hydriodic acid-reducible S, 0.01 M CaCl2, and 0.04 M Ca(H2PO4)2-extractable S fractions, and soil pH. Soil inorganic and organic S fractions extracted by NaHCO3 and NaOH extractants were also determined. The results obtained showed that camp soils contain higher soil pH, organic C, total N, total S, organic (C-bonded S and hydriodic acid-reducible S) and inorganic S fractions, NaHCO3-and NaOH-extractable soil S fractions but a lower anion retention capacity than non-camp soils, attributed to a higher return of plant litter and animal excreta to camp soils. In both soils, total S, organic S, C-bonded S, and hydriodic acid-reducible S were significantly correlated with organic C (r≥0.90***, ***P≤0.001) and total N (r≥0.95***), suggesting that C, N, and S are integral components of soil organic matter. However, C: N : S ratios tended to be lower in camp (60: 5.6: 1–103: 7.2: 1) than in non-camp soils (60:6.1:1–117:8.3:1). Most (>95%) of the total soil S in camp and non-camp soils is present as organic S, while the remainder is readily soluble and adsorbed S (i.e. Ca(H2PO4)2-extractable S). C-bonded S and hydriodic acid-reducible S constituted 55%–74% and 26%–45% of total S, respectively, reflecting a regular return of plant litter and animal excreta to the grazed pastures. NaHCO3, and especially NaOH, extracted significantly higher amounts of total soil S (13%–22% and 49%–75%, respectively) than Ca(H2PO4)2 or CaCl2 ( 45%) contain higher levels of C-bonded and hydriodic acid-reducible S fractions than those of low sulphate retention soils (

A laboratory study was conducted to investigate whether the Zn‐Na acetate solution, used for trapping H2S in the Johnson‐Nishita method (1952), could be used to quantitatively determine 35S and 32S in the same trapping solution, as the Zn‐Na acetate solution allows more sensitive S determination using methylene blue than does the bismuth sulphide colour development of H2S trapped in NaOH solution. Results obtained using the Zn‐Na acetate solution were variable compared with those obtained from the normal procedure of using NaOH as the H2S trapping solution, indicating that the Zn‐Na acetate solution was unsuitable, probably because of the rapid transformation of H2S to water‐insoluble ZnS. The applicability of methylene blue development for H2S trapped in NaOH solution was also investigated. Results showed that 32S could be determined quantitatively provided methylene blue colour development was conducted less than 30 minutes after the removal of H2S‐trapping NaOH solution from the Johnson‐Nishit...

SummarySulphur (S) cycling and losses in irrigated, sheep-grazed pastures receiving annual superphosphate (SP) applications for 35 years at rates of 0, 188 and 376 kg/ha were studied using a mass-balance approach which accounted both for S inputs to and outputs from the soil-plant-animal system. Total recoveries of applied S in the 188 and 376 kg SP/ha treatments were estimated to be 35·2 and 21·2% respectively. Over 65·0% of the applied S was not recovered, and this was attributed to leaching losses beyond the major rooting zone (0–300 mm), lateral S transfer by irrigation water and cxcretal S transfer to stock camps. The lower S recovery in the 376 compared with the 188 kg/ha per year treatment was probably due to a higher accumulation of soil phosphorus (P), which might have competed with sulphate (SO42-) for adsorption sites on soil colloids. Superphosphate applications resulted in the accumulation of soil organic S (S0) fractions (hydriodic acid-reducible and carbonbonded S) to a soil depth of 300 mm in both camp and non-camp areas. However, an increase in SP applications from 188 to 376 kg/ha per year did not lead to a further accumulation of soil S0 fractions. Approximately 50% of this additional S input was estimated to be leached beyond the 300 mm depth. The presence of soil So fractions at 300 mm soil depth, especially in camp areas, suggests that leaching occurred, involving not only SO42- but also So fractions from soil, plant litter, root residues and animal excreta, as the soil had a low SO42- retention capacity. These leaching losses may limit the ability of soil S reserves to sustain adequate S for pasture production when S fertilizer application is withheld.

SummaryPhosphorus (P) cycling and losses in irrigated, sheep-grazed pastures receiving superphosphate (SP) applications for 35 years at annual rates of 0, 188 and 376 kg/ha were studied using a massbalance approach which accounted both for P inputs to and outputs from the soil-plant-animal system. Total recoveries of applied P in the soil-plant-animal systems in the 188 and 376 kg SP/ha treatments were 94 and 83% respectively. Approximately 52–53% of the applied P was recovered in the soil within the major plant rooting zone (0–300 mm soil depth). These data suggest that P leaching losses from SP fertilizer, plant litter, root residue and sheep faeces were unlikely to occur beyond the major plant rooting zone. However, the transfer of excretal P to stock camps and the transport of P from SP fertilizer, plant litter and sheep faeces via the irrigation water along the border from the top to the bottom of the irrigated border strip accounted for less than 6% of the applied P. Superphosphate applications resulted in the accumulation of both soil inorganic and organic P fractions to a depth of 225 mm. The accumulation of soil inorganic P was most pronounced when SP was applied annually at the rate of 376 kg/ha, which was in excess of pasture P requirements.

Diagnosis and Recommended Integrated System (DRIS) norms and indices for N, P, K, Ca and Mg were developed for apple trees in Canterbury, New Zealand, based on surveys of nutrient levels of apple leaves in field experiments before and after N and K fertiliser applications and in four orchard surveys over a period of three years. Comparisons were made between calculated norms based on mean sufficiency nutrient levels and published norms. Results obtained showed that calculated norms and indices from sufficiency range provide a good indication of the order of apple nutrient requirements. High N and low Ca were identified as major nutrient problems. The best period for sampling leaves for nutrient analysis is at 3 to 5 months after blossom (i.e., December to January in New Zealand).

The radiocarbon dating of volcanic ash (tephra) deposits in New Zealand has been difficult on sites remote from the eruption, which contain either little carbon or degraded and contaminated charcoal. Although many studies of contamination removal from macroscopic charcoals from tephra sequences have been made, little attention has been paid to those containing no visible charcoal, because of the difficulty of obtaining sufficient carbon for radiometric dating. We report here experiments using accelerator mass spectrometry to establish a reliable method for dating a low-carbon aeolian and peat deposit containing a tephra horizon. Results so far demonstrate that improvements to existing chemical pretreatment methods are possible, and that dates obtained on oxidized fine-grained residues can approach the maximum age determined on good quality charred wood samples.

Changes in soil pH, exchangeable aluminium (Al), calcium (Ca), magnesium (Mg), and potassium (K) and extractable manganese (Mn) were investigated after urea fertigation of a sandy loam soil in an apple orchard in New Zealand. Urea at three rates (0, 25, 50 kg N ha−1 yr−1 or 0, 16.9, 33.8 g N emitter−1 yr−1) was applied in 4 equal fertigations. Soil cores at 4 profile depths (0–10, 10–20, 20–40 and 40–60 cm) directly below and 20 cm from the emitter were sampled approximately 4 weeks after each fertigation and in the following winter. Results obtained showed that the largest changes in soil pH and cations occurred in soils directly below the emitter in the 50 kg N ha−1 yr−1 treatment where the soil pH decreased by 1.6 pH units at all soil depths. The lowest pH of 4.3 was observed at a depth of 27 cm. Exchangeable Al and extractable Mn levels increased to 11 meq kg−1 and 78µg g−1 respectively. Estimated losses of Ca, Mg and K from the upper soil profile depth (0–10 cm) represented 23, 63 and 27% of their respective total exchangeable levels. At lower profile depths (>20 cm), accumulation of displaced K was evident. Variable, and generally non-significant, chemical changes recorded in soils 20 cm from the emitter were attributed to restricted lateral water movement, and therefore urea movement, down the profile.

This paper investigates a ARM and FPGA-based hybrid-processors real-time embedded Linux platform. This platform is designed as a general purpose embedded system that can be fitted into a number of applications such as digital controller, embedded web server or base station in wireless sensor networks. However, its hybrid-processors feature makes it a perfect experimental platform for scientific research. In this paper, we will discuss some of the basic functions as well as advanced features of this platform. We will also discuss briefly how this platform could be useful for a scientific research by sharing computational load in hybrid-processors.

The IEC 61499 Function Block is an open standard for distributed control and automation. However, work related to using IEC61499 as code generator for various programming languages is still lacking. In this paper, a methodology for code generation based on XML and EBNF is discussed. Along with this code generator, an Iterative Knowledge Based Data Library (IKBDL) is proposed to improve the accuracy of the target codes. An example of converting XML codes generated from Function Block into SystemC language is demonstrated.

Verification of logic controllers can identify errors during the design stage so they can be remedied and prevent some faults from occurring once the system is running. Input order robustness is the property that multiple inputs arriving in a variety of orders, and regardless of the order, produce the same set of outputs and same final state. Verifying this property ensures determinism of the closed-loop system even if the environment is non-deterministic. Because use of the IEC 61499 standard for distributed control is becoming more widespread, we present the application of input order robustness verification to controllers implemented in this formalism. Open issues with IEC 61499 execution semantics are presented and discussed in relation to input order robustness verification.

Effects of clearfell logging and clearfell logging and burning on forest floor biomass and nutrient status were investigated in a Nothofagus forest in the West Coast of the South Island of New Zealand. Field plots consisting of replications of different intensities of burning were used in the study. Fire consumed most of the non-humus floor components but little of the humus due to substantial amounts of moisture in the humus layer. During burning, mean litter surface temperatures reached 586°C. The burning intensity was considered light to moderate. The quantity of organic matter consumed by fire was about 21 000 kg/ha. Ash weights produced ranged from 3700 to 4400 kg/ha after taking into account the small sample size measured. Nutrient losses in the material consumed by fire were especially high for N (66%), P (35%), and S (51%) but were low for other nutrients studied (

Radiocarbon dates obtained for peats and organic silts from the high rainfall/leaching environment of North Westland have been shown to conflict with known stratigraphic evidence by yielding anomalously young dates. This study examines the effectiveness of 14 chemical pretreatment methods, including classical humus fractionation of soil organic matter, hydrolysis with mineral acids (6 M HC1 and 70% HNO3), and extraction of lipids and cellulose, in removing young carbon contaminants from peat and organic silt samples prior to radiocarbon assay. The criterion chosen for judging the effectiveness of a treatment in removing young contaminants is an increase in 14C age, with the assumption that contamination is largely due to young carbon. Chemical pretreatments were undertaken on peat and organic silt samples taken immediately above (5–0 cm) and below (0–5 cm) a layer of Kawakawa Tephra found at Grahams Terrace in North Westland. Radiocarbon dates, obtained by accelerator mass spectrometer (AMS), sho...

Cutting force and vibration are two major characteristics that reflect the tool state in the milling process. Measurement of vibration on the workpiece or the fixture of the workpiece is one of the indirect methods to evaluate the effects of the cutting force. Currently, there is a lack of tool breakage monitoring solutions using vibration sensor in ball end milling operation. The work described in this paper is aimed at the exploration of an on-line monitoring strategy to make use of accelerometer signals. Our experimental investigations provided sufficient evidence that accelerometer signals are sensitive to tool breakage in ball-nose end milling.

The paper presented the IEC 61499 based run-to-run controller for chemical mechanical planarization process. Experiments show the needs of adjust the removal rate based on the actual data captured from manufacturing line rather than default values to calculate removal rate for every lot and use removal rate to calculate polish time for the next lot which would be polished next in the polish tool. Two key components of the controller namely removal rate calculation and polish time calculation was developed and the result from both components was captured and analyzed.

A field experiment was conducted to determine the effect of frequency of 15N tracer applications on the estimation of nitrogen (N) fixed by clover plants in an established mixed grass/clover pasture using the 15-enrichment technique. The results obtained showed that N derived from the atmosphere (%Ndfa) significantly decreased when 15N tracer was applied daily (87.2%) or at a 30-day interval (76.3%), after the first 30 days of regrowth. This effect did not persist at a further harvest, except on pastures treated with 150 kg N/ha of unlabelled fertiliser N. The estimate of the amount of N fixed was not significantly affected by the frequency of 15N applications but decreased from 36.7 to 19.8 kg N/ha after 60 days with fertiliser N application (150 kg N/ha). The mean daily rate of N fixation increased in the zero N treatment from 0.89 kg N/ha per day during the first 30 days regrowth to 1.36 kg N/ha per day during a subsequent 30 days of uninterrupted growth. Overall, the results showed that the 1...

The effects of two organic (blood and bone, compost) and two inorganic (potassium nitrate, KNO3; ammonium sulphate, (NH4)2 SO4) forms of nitrogen (N) fertilisers on the yield and some quality indices of tomatoes were studied in a pot experiment using Waimairi peaty loam soil obtained from an area currently used for vegetable production. Four rates (0,150, 300, 600 kg N/ha, based on soil bulk density) of each fertiliser form were used. Fruit yield was significantly correlated with foliage N concentration, but not with fruit N concentration. Increasing rates of all N fertilisers, except compost, produced significant increases in fruit yield. Compared with the control, at 600 kg N/ha applied, compost increased fruit yield by 40% only whereas the other N fertilisers studied increased fruit yield by 120%. Fruit quality indices measured showed variable response to treatments. Fruit colour increased significantly on application of blood and bone, (NH4)2 SO4, and KNO3, whereas compost showed no effect. F...

Effects of chloride (Cl) fertilisers (NaCl and KCl) on the ionic composition (K+, Ca2+, Mg2+, Na+, NH+ 4, H2PO- 4, SO2- 4, Cl-, NO- 3), and cation-anion (C-A) balance and ratio of fodder beet (Beta vulgaris L.) were studied under field conditions on two New Zealand soils (Templeton siltloam, Dystic Ustochrept; and Wakanui silt loam, Aquic Eutrochrept). In both soils, at mid season and final harvest, Cl application at 360 kg/ha (590 kg NaCl and 758 kg KCl) increased root K+ and Cl-, and Cl- in tops consistently but not K+ in tops. The sum of cations (SC) and C-A remained unaffected whereas the sum of anions (SA) increased. With increasing rates of NaCl, root cations were not significantly affected whereas topsand root Cl- increased linearly, indicating that Cl- was easily absorbed and accumulated in both tops and roots of the beet crop. The beet crop maintained constant SC and C-A balance within the range of 0–1180 kg NaCl/ha applied, but the SA increased linearly with increasing rates of NaCl app...

Topsoil samples (0–75mm) collected at the beginning ofeach growing season over a 35-year period from grazed pastures receiving annual superphosphate applications at rates of 0, 188, and 376 kg/ha per year were analysed for changes in soil organic nitrogen (N), total carbon (C),organic sulphur (So), hydriodic acid-reducible S (HI-reducible S), carbon-bonded S (C-bonded S), and readily-soluble plus adsorbed S. In addition, soils from subsoil depths (75–300 mm) were also sampled at the beginning of each growing season for 3 years to investigate the effects of superphosphate applications on So, readily-soluble plus adsorbed S, microbial S, and arylsulphatase activity. Results obtained showed that over 95% of soil S was in So and the remainder was in readily-soluble plus adsorbed S. Applications of superphosphate to increase S fertiliser inputs from 0 to either 21 or 42 kg S/ha per year, substantially enhanced the accumulation of So, HI-reducible S, and C-bonded S fractions. However, there was no furt...

SUMMARYThe nature and availability of phosphorus in long-term fertilized pasture soils was investigated in a series of field trials, which included liming, N fertilizer and cultivation and involved monitoring plant P uptake and changes in topsoil (0–7·5 cm) P fractions for 2 years (1982–83). Liming increased soil organic P mineralization. This was indicated by significant decreases in extractable organic P and concomitant increases in microbial biomass P in the limed soils, although these changes in soil P had no significant effect on pasture yield and P uptake. On the other hand, N fertilizer increased pasture yield and P uptake but had little effect on the amounts of P in the different soil P fractions. In the cultivated soils, increases in plant-available inorganic P were attributed to the release of P during decomposition of plant residues, while the maintenance of fallow conditions decreased amounts of microbial P in these soils.

Early detection of system failure required continuous monitoring of electro-mechanical system which required embedded prognostics devices. Unfortunately, the current research and industrial solutions do not provide a user friendly and rapidly configurable environment to create 'adaptive microprocessor size with supercomputer performance' embedded solution in order to reduce downtime. Developing a solution for various industrial domains can be too time-consuming because the tools and rapid methods for creating embedded reconfigurable solutions are lacking. In this paper, we present a proof of concept of a rapid configurable embedded development environment using IEC 61499 Functional Blocks. Two test cases, which include an XOR Gate for Field Programmable Gate Array (FPGA) and a PID tank level controller for an ARM based Linux embedded system are used in the paper to discuss the potential of the framework. Finally, a research agenda towards a distributed cluster head/sensor nodes distributed prognostics concept is identified.

Large volume of data generated by manufacturing plants requires suitable techniques for extraction of useful information of the operational status of the process. By distributing the capabilities of data processing close to sensor level, the response time will be reduced and the accuracy of analysis will be improved. A new conceptual sensor node developed for distributed data rectification is presented. The node realizes data collection and nonlinear search within resource-limited systems using the reconfiguration capabilities of an SRAM-based field-programmable gate array. The node can effectively analyze data through online dynamic programming-like algorithms and be applied into a class of problems where the objective is to capture characteristics of sensors data while optimizing performance objective functions.

With the fast changing global business landscape, manufacturing companies are facing increasing challenge to reduce cost of production, increase equipment utilization and provide innovative products in order to compete with countries with low labour cost and production cost. On of the methods is zero down time. Unfortunately, the current research and industrial solution does not provide user friendly development environment to create "Adaptive microprocessor size with supercomputer performance" solution to reduce downtime. Most of the solutions are PC based computer with off the shelf research software tools which is inadequate for the space constraint manufacturing environment in developed countries. On the other hand, to develop solution for various manufacturing domain will take too much time, there is lacking tools available for rapid or adaptive way of create the solution. Therefore, this research is to understand the needs, trends, gaps of manufacturing prognostics and defines the research potential related to rapid embedded system framework for prognostic.

Based on the numerical inverse kinematic algorithm developed for modular robots, this paper presents a new control method, termed joint angle increment redistribution, which makes that the maximum allowable joint rates of a redundant robot can be specifically defined according to the internal and external constrains such as joints, tasks, and environments. For example, if some joints have failures and need to be locked, the corresponding joint angle increments can be redistributed to be zero or very small values. The proposed approach can be readily used for online fault-tolerant control of redundant robots. It also makes the optimal control with multiple performance criteria easy. The effectiveness of the proposed algorithms has been demonstrated by a 7-DOF serial modular robot for the avoidance of joint angle limits.

Soil acidity poses a serious limitation to pasture production in southern Australia. While surface acidity can be overcome by top-dressing with lime, amelioration of subsurface acidity is difficult because of the slow movement of lime to depth. The effectiveness of two organic (citrate and fulvate) and two inorganic calcium compounds (chloride, and phosphogypsum) in ameliorating subsoil acidity was investigated in 25 cm long columns of unsaturated soil by studying the movement of the compounds and their potential to remove exchangeable Al and reduce the Al concentration in the soil solution. Results showed that calcium citrate raised the soil solution pH from 4.5 to a maximum value of 7 in the upper portion of the column, and that calcium chloride, phosphogypsum and the fulvate solution had little effect on soil solution pH. Treatment with calcium citrate or the fulvate solution, that contained 51 mM Na, removed the bulk of the exchangeable Al from the column. The cation exchange sites in the upper 10 cm of the column were saturated with Ca, and the cation exchange capacity of the soil was increased from 3.5 to 8.0 cmolc kg-1 in the calcium citrate treatment. In contrast, the above changes were not shown by the calcium chloride and phosphogypsum treatments. The Ca concentration in the leachate was equivalent to that in the inflowing solution and is evidence of Ca being transported through the entire column. These results suggest that Ca alone was not able to displace Al from the exchange sites and a strong complexing agent such as citrate or fulvate is needed.