Efficient Production Techniques Research Articles

Current North Korean Economy: Overview and Prospects for Change

IntroductionThe North Korea of the 1990s was associated with stark images of economic disruption and famine. Although economic distress and famine have subsided since 1998, North Korean food shortages and industrial recession have persisted to the present. Battered by a nearly bankrupted economy and continuous shortages of capital, energy and food, North Korea (the North) has recently been opening its doors to strike political and economic deals.North Korea's economy has resulted in low industrial productivity and efficiency, technological backwardness, and, in the end, economic stagnation. The North Korean economy withered to the point that almost all of its sectors no longer functioned properly. Confronted with economic difficulties and no options for rehabilitating the economy without international help, the North undertook drastic measures for reforming its economy. The move has been toward a market economy with a price mechanism aimed at fostering industrialization, deviating from its traditional planned economy. Rudimentary market economics have gradually been introduced to the North's centralized economic system and its functions.Economic System and Its DysfunctionThe North possessed a unique type of command economy based on a system of self-reliance, Juche. The North's economy was characterized by state ownership of means of production and centralized economic planning and command, and emphasized military development. The North's economy got into trouble as it grew more complex, having difficulties in controlling the many intertwined variables of the economic system in the absence of a market mechanism for allocating resources and distribution. The centrally planned system lacked entrepreneurship, and the North's central planning did not allow the profit motive and did not reward innovation and enterprise.The prices of goods and services were derived from labor costs, not through the pricing mechanism of supply-and-demand interactions. The North's commercial management system was made up of wholesale commerce, which was controlled by the central government, and retail commerce, which was controlled by the regional governments. The government was therefore the North's sole source for the production and distribution of goods.1As a result, there was no private gain incentive to managers or workers for improving product quality or developing more efficient production techniques. Enterprise managers and workers actually resisted government-imposed innovations because higher and sometimes-unrealistic production targets usually accompanied them. Innovation also lagged because of a lack of competition. Entrepreneurs were essentially government-owned monopolies, and the North's innovation was often resisted. There were no new startup firms, driven by the profit motive, to introduce better products, superior managerial techniques, or more efficient production methods.Over an extended period, enterprises produced the same products with the same techniques, even as both the products and techniques became increasingly obsolete by world standards. The individual worker lacked motivation to work hard because there were few material incentives. Because of the low priority assigned to consumer goods in the production plans, only a limited array of inferior goods and services was available to consumers. The North's economic self-sufficiency also isolated its enterprise from import competition. The North kept recording minus growth or economic stagnation in most of the 1990s, and with all the efforts and measures on its part there were hardly any signs of economic recovery, as shown in Table 2.Changing Economic Situation and Reform MeasuresThe North's workers found it increasingly difficult to make ends meet on their wages, which companies were often not able to pay regularly due to frequent suspension of operations because of power shortages and a lack of basic raw materials and intermediate products. …

Femtosecond laser writing of nanostructures on bulk Al via its ablation in air and liquids

We report on the formation of self-organized nanostructures (NS) on bulk Al under its ablation in air and liquids with femtoseconds (fs) laser pulses. In case of exposure into liquids, NS are regularly formed on the Al surface with an average period of about 200 nm, independent of the laser polarization. A dispersion of Al nanoparticles (NPs) into the liquid additionally occurs. Irregular nano-bumps are produced when the irradiation is performed in air. NP dispersions as well as NS formed on Al surface show a characteristic absorption peak in the near UV which has been attributed to plasmon oscillation of electrons. The wings of this peak extending to the visible, lead to a distinct yellow coloration of the processed Al surface and the liquid dispersions. Ultrafast laser processing of bulk Al in liquids may be potentially a promising technique for efficient production of nanosized aluminum.

Aib e substrato na produção de mudas de mirtilo cv. "Climax" através de microestaquia

Embora no Sul do Brasil o mirtilo esteja sendo pesquisado e produzido como uma nova alternativa na fruticultura, a maioria das mudas produzidas são obtidas pela propagação vegetativa, através do uso de estacas, e os resultados obtidos são insatisfatórios. Dessa forma, o objetivo deste trabalho foi testar a capacidade de enraizamento de mirtilo "rabbiteye", através da técnica de microestaquia. Microestacas provenientes de plantas aclimatadas de Vaccinium ashey Reade, cv. "Climax", obtidas através de micropropagação, foram testadas. O experimento foi conduzido em casa de vegetação usando dois tipos de microestacas (média e apical), dois substratos (areia e Plantmax®) e três concentrações de AIB (0, 1000 e 2000mg L-1). Aos 60 dias após a instalação do experimento, foi avaliada a percentagem de microestacas enraizadas, a percentagem de microestacas sobreviventes, o número médio de raízes por microestaca, o comprimento médio das raízes e o comprimento da raiz mais desenvolvida. Concluiu-se que a microestaquia pode ser uma técnica eficiente na produção de mudas de mirtilo, através do uso de plantas-matrizes micropropagadas. O emprego de microestacas oriundas da porção mediana proporcionou elevados índices de enraizamento e sobrevivência, independentemente da concentração de AIB utilizada. Por outro lado, para microestacas apicais, a aplicação de AIB foi fundamental para o enraizamento.

Nutrient optimization for the production of citric acid by Aspergillus niger NRRL 567 grown on peat moss enriched with glucose

Citric acid is an effective remediation agent for soils contaminated by heavy metals. The large-scale field use of this organic acid requires the development of efficient production techniques using low cost substrates such as sugar rich wastes. To develop such techniques, the objective of the project was to simultaneously optimize the initial glucose, nitrogen (N), phosphorus (P) and NaCl levels of a nutrient solution used to wet peat moss (PM) simulating a sugar rich waste on which Aspergillus niger NRRL 567 was grown to produce citric acid. Seventeen different combinations of nutrients were tested to grow A. niger at 30 °C for 48 and 72 h, and to measure the resulting citric acid production. With the central composite design method (CCD), the results were used to produce a second order equation defining citric acid production as a function of initial glucose, N, P and NaCl levels. Initial glucose and N levels were found to have a significant positive and negative effect on citric acid production, while P and NaCl were found to have a limited positive and an insignificant effect, respectively. A peak citric acid production of 82 g kg −1 dry peat moss (DPM) was reached after 72 h with the following optimized nutrient solution, in terms of g kg −1 DPM: 967.9 glucose, 15.4 (NH 4) 2SO 4, 43.9 KH 2PO 4 and 4.0 NaCl. This represented a 50% increase in production, over a shorter fermentation period, compared to a basal nutrient solution optimize solely for initial glucose level.

Impact of de-coupling agricultural support on dairy investment and milk production volume in Finland

This study analyses the impacts of de-coupling of agricultural support from production in Finland. A dynamic agricultural sector model, which includes 17 production regions and endogenous investments and technical change, is used in the analysis. Investment in different production techniques is dependent on the relative profitability and the spread of each technique in the population of heterogeneous farms. There are relatively few large farms which use efficient production techniques in Finland. De-coupling weakens the incentive for investment in dairy production and causes a temporary but significant slow down in dairy investments and technical change. Consequently, de-coupling is likely to result in a significant drop in milk and beef production in the next 10–20 year period if no corrective measures are taken in agricultural policy in less-favoured areas such as Finland. However, a slow recovery of investment and output levels are expected in the long run.

Efficient Production of Polyploid Plants via Protoplast Culture of Iris fulva

In protoplast culture of the Louisiana iris species, Iris fulva (2n=42), N6 medium supplemented with 1 mg/l 2,4-D, 1 mg/l kinetin, 200 mg/l casein hydrolysate, 250 mg/l proline, 0.3 M glucose and 2.5 g/l gellan gum was suitable for cell division and colony formation. When colonies formed were transferred to plant growth regulator free MS medium, 61 plant lines were regenerated via somatic embryogenesis. Flow cytometric analysis revealed that leaf tissue of I. fulva consisted of 2C, 4C and 6C cells. Consequently, we identified this species as polysomatic in the genus Iris. Such polysomaty was also recognized in the suspension calli. Sixty one plant lines obtained by protoplast culture consisted of 25 diploid (41.0%), 1 triploid (1.6%), 29 tetraploid (47.5%) and 6 hexaploid lines (9.9%). In addition, chromosome analysis showed that somatic chromosome numbers of the diploid, hypertriploid and tetraploid lines were 2n=42, 67 and 84, respectively. On the other hand, all lines regenerated from suspension culture of I. fulva were diploid lines in contrast to the results from protoplast culture. Thus, it can be concluded that protoplast culture of this species is an efficient technique for production of polyploid plants.

Beta-poly(L-malate) production by non-growing microplasmodia of Physarum polycephalum. Effects of metabolic intermediates and inhibitors.

The production of beta-poly(L-malate) (PMLA) by non-growing microplasmodia of Physarum polycephalum was investigated. Growth was minimal in culture medium devoid of nitrogen source, but PMLA production occurred at a substantial rate. The addition of metabolic intermediates, malate, fumarate, succinate, and oxaloacetate, and the omission of hematin showed considerable growth inhibition in the presence of the nitrogen source, while PMLA production per unit biomass increased significantly. The results indicated that PMLA production was dissociated from biomass production under these conditions. The stimulating effect of carbonate on PMLA production was independent on growth. Cultivation in the absence of the nitrogen source and hematin or in the presence of the metabolites may be a useful technique for efficient PMLA production at a minimum of biomass production.

β-Poly(L-malate) production by non-growing microplasmodia of Physarum polycephalum: Effects of metabolic intermediates and inhibitors

The production of β-poly(L-malate) (PMLA) by non-growing microplasmodia of Physarum polycephalum was investigated. Growth was minimal in culture medium devoid of nitrogen source, but PMLA production occurred at a substantial rate. The addition of metabolic intermediates, malate, fumarate, succinate, and oxaloacetate, and the omission of hematin showed considerable growth inhibition in the presence of the nitrogen source, while PMLA production per unit biomass increased significantly. The results indicated that PMLA production was dissociated from biomass production under these conditions. The stimulating effect of carbonate on PMLA production was independent on growth. Cultivation in the absence of the nitrogen source and hematin or in the presence of the metabolites may be a useful technique for efficient PMLA production at a minimum of biomass production.

Growth and Yield of F1 Hybrid Peaches Developed from Doubled Haploids

Doubled haploid peach [Prunus persica (L.) Batsch] lines were cross-pollinated to produce F1 hybrids. F1 hybrids were evaluated at 3, 7, 8, and 9 years after field planting for tree growth as measured by trunk cross-sectional area, and for fruit production as measured by total weight, total number, and production per unit trunk cross-sectional area. Fruit quality of most F1 hybrids was within the range of quality observed in progeny of standard peach cultivars, and tree growth and productivity were similar to those of standard cultivars. F1 hybrids present the possibility of developing scion varieties that can be produced from seed, thus eliminating the need for grafting scions onto rootstocks in situations where specific, adapted rootstocks are not necessary. They could also be used to develop genetically uniform seed-propagated rootstocks. The use of doubled haploid-derived F1 peach hybrids, however, would require reliable, efficient production techniques.

Efficient linac-based production of slow positrons

A novel technique for efficient production of slow positrons is proposed. It is based on the trapping of electroproduced relativistic positrons in a high field magnetic bottle. By introducing a small drift motion the emitted positrons are prevented from re-striking the production target and they undergo extended radiative cooling. By adding high voltage electrostatic trapping the cooling can proceed down to very small transverse momenta. In the simplest version of the method the wide distribution of final longitudinal momenta is conserved until a dedicated extraction procedure converts the trapped positrons into a quasi-continuous beam of very low energy. What comes out is a slow positron beam with the same quality as that obtained with the standard moderation scheme. The conversion efficiency is around 0.01 e +/e − and beam intensities exceeding 10 11 e +/s can be obtained with a moderate linac average current.

Callus culture and plantlet production in Carica papaya (Var. Honey Dew)

In order to develop techniques for efficient callus production and regeneration in Carica papaya (Var. Honey Dew), lamina, petiole, stem and root explants from in vitro plantlets were cultured in media supplemented with 2.0 mg/1 IBA and 0.5 mg/1 BAP. Use of in vitro-grown plantlets as an explant source helped to avoid contamination common in papaya tissue culture. Callusing was maximum in root explants cultured in a modified MS (half-strength) medium. Shoot reganeration was maxium in root-derived callus grown in full-strength modified MS medium supplemented with 0.5 mg/1 IBA and 1 to 2 mg/1 kinetin. A histological study indicated that shoot buds originated from peripheral cell layers of the callus. Each shoot regenerated from callus was subcultured using a multiplication medium. Root formation was induced in all shoots treated in half-strength of modified MS medium containing 2 mg/1 IBA and rooted shoots were transferred successfully to the field.

Hydrogen as an energy carrier: What is known? What do we need to learn? A consideration of the parameters

Hydrogen is at present an important raw material for the synthesis of chemical compounds and for the processing of mineral oil, as well as an essential fuel for space transportation. Starting from present knowledge gained by working with hydrogen, the authors describe research and development needs and suggest some hydrogen energy applications which have early market possibilities. Since technical developments seem to be proceeding well, the main thrust of the paper is concerned with the efficient use of hydrogen as an energy carrier, as well as with the political and economic considerations associated with its introduction to the marketplace. Using the example of solar energy conversion technologies, the paper discusses the most important cost factors associated with the production of solar hydrogen as well as the dynamics of cost developments in the related technologies. It seems appropriate to conclude that with further research and development and with more efficient production techniques and large-scale operation significant cost reductions can be expected. But as long as current energy policies and the energy economy support the practice of not “internalizing” the costs of environmental damage, (and the further costs which ensue from this damage), the opportunity to build up an ecologically defensible energy economy will continue to be missed. The paper gives examples of external costs for energy conversion and relates them to internal costs. Noting that technical problems are increasingly being solved faster than are the non-technical ones, the paper concludes with a plea to continue research on and development of a unified “solar energy and solar hydrogen” system, one which includes all the relevant technical, economic, ecological, and political factors.

Characterization of regiospecific AC- and AD-disulfonate capping of .beta.-cyclodextrin. Capping as an efficient production technique

Etude de la reaction de «coiffage» regioselectif de la β-cyclodextrine en utilisant une serie de dichlorures de sulfonyle aromatiques rigides ClSO 2 ×SO 2 Cl (avec X=methylene-4,4' bis-benzene, oxy-4,4' bis-benzene, carbonyl-4,4' bis-benzene, methyl-9 carbazole-3,6)

Autolysis: A tool for protoplast production from Aspergillus nidulans

The rate and degree of autolysis of Aspergillus nidulans was investigated during a 16 day incubation period. Changes in the activity of chitinase, B -glucanase, α-glucanase, invertase, esterase, acid and alkaline phosphatase and protease liberated into the culture fluid were monitored during growth and autolysis. Protoplasts were released from A. nidulans mycelium by lytic enzymes present in autolytic-phase culture filtrates of the same organism. Maximum protoplast-liberating activity corresponded to both the point of maximum autolysis and maximum lytic enzyme activity. The method described represents a highly efficient and reliable technique for protoplast production from Aspergillus nidulans .

The petroleum exponential (again)

The U.S. production and reserves of liquid and gaseous petroleum have declined since 1960, at least in the lower 48 states. This decline stems from decreased discovery rates, as predicted by M. King Hubbert in the mid‐1950's. Hubbert's once unpopular views were based on statistical analysis of the production history of the petroleum industry, and now, even with inclusion of the statistical perturbation caused by the Prudhoe Bay‐North Alaskan Slope discovery (the largest oil field ever found in the United States), it seems clear again that production is following the exponential curve to depletion of the resource—to the end of the ultimate yield of petroleum from wells in the United States.In a recent report, C. Hall and C. Cleveland of Cornell University show that large atypical discoveries, such as the Prudhoe Bay find, are but minor influences on what now appears to be the crucial intersection of two exponentials [Science, 211, 576–579, 1981]: the production‐per‐drilled‐foot curve of Hubbert, which crosses zero production no later than the year 2005; the other, a curve that plots the energy cost of drilling and extraction with time; that is, the cost‐time rate of how much oil is used to drill and extract oil from the ground. The intersection, if no other discoveries the size of the Prudhoe Bay field are made, could be as early as 1990, the end of the present decade. The inclusion of each Prudhoe‐Bay‐size find extends the year of intersection by only about 6 years. Beyond that point, more than one barrel of petroleum would be expended for each barrel extracted from the ground. The oil exploration‐extraction and refining industry is currently the second most energy‐intensive industry in the U.S., and the message seems clear. Either more efficient drilling and production techniques are discovered, or domestic production will cease well before the end of this century if the Hubbert analysis modified by Hall and Cleveland is correct.

Manufacture and Production of Prestressed Concrete

Reviews the major developments in the manufacture and production of precast and prestressed concrete in North America during the past 25 years and outlines future possibilities affecting the industry. The impetus for getting the precast prestressed industry started was the excitement generated by the construction of Philadelphia's Walnut Lane Bridge. However, the key to the success of the billion dollar industry was the development of efficient and economical mass production techniques.