A BIOECONOMIC ANALYSIS OF THE NORWEGIAN SPRING SPAWNING HERRING (NSSH) STOCK

A biological model belonging to the Beverton-Holt age-structured family for the Norwegian spring spawning herring (Clupea harengus) (NSSH) is simulated, the outcome of which compares well with actual data on the fishery. This model is then combined with an economic model to help investigate how optimal a management policy of constant fishing mortality will be for a fishery such as the NSSH, which has a highly fluctuating stock biomass. For the range of constant values of fishing mortality explored, and a simulation time horizon of 20 years, a constant fishing mortality of 0.15 turns out to be economically optimal. It should be noted that this result is sensitive to variations in the assumptions underlying key variables of the fishery. For example, when a constant rather than variable recruitment was assumed, a different optimal fishing mortality rate was obtained.bioeconomic model, herring optimal management, Resource /Energy Economics and Policy, Q57, Q22, Q28,

Design of Robust Digital Pole Placer for Car Active Suspension with Input Constraint

This chapter deals with the problem of state feedback control for an active quarter-car suspension system with control input constraint. The dynamics of the suspension system is first formed in terms of the control objectives: ride comfort, suspension deflection, and maximum actuator control force. The control task is formulated as robustly placing the closed poles in a desired region against different passenger load. Since digital computers are widely used in the vehicle industry, a new saturated controller design method is presented for regional pole-placement of uncertain discrete time systems. The constraint of control input saturation is considered in the design phase. The desired dynamic performance for uncertain discrete-time systems is represented by the settling time and damping ratio. A sufficient condition is derived to place the poles in a desired region. The design is formulated in terms of linear matrix inequality optimization. The effectiveness of the proposed design is illustrated by applying it to a quarter?car active suspension system. Different road tests for the proposed controller are carried out: step and bump disturbances. The proposed design achieves the desired oscillation damping due to road disturbances in addition to passenger comfort. The results are compared with the passive suspension system

A Comparative Taxonomy of Parallel Algorithms for RNA Secondary Structure Prediction

RNA molecules have been discovered playing crucial roles in numerous biological and medical procedures and processes. RNA structures determination have become a major problem in the biology context. Recently, computer scientists have empowered the biologists with RNA secondary structures that ease an understanding of the RNA functions and roles. Detecting RNA secondary structure is an NP-hard problem, especially in pseudoknotted RNA structures. The detection process is also time-consuming; as a result, an alternative approach such as using parallel architectures is a desirable option. The main goal in this paper is to do an intensive investigation of parallel methods used in the literature to solve the demanding issues, related to the RNA secondary structure prediction methods. Then, we introduce a new taxonomy for the parallel RNA folding methods. Based on this proposed taxonomy, a systematic and scientific comparison is performed among these existing methods

Self-rated health status, functional difficulties in health domains and non-communicable diseases in Oman: Evidence from the World Health Survey in Oman

This paper examined the pattern of self-rated Health (SRH) status, functional difficulties in health domains and non-communicable diseases among the Omani adult people. The paper also evaluated the association of SRH with the health functional difficulties and the chronic diseases. The data for the study obtained from the 2008 Oman World Health survey, involving a nationally representative sample of 3,770 Omani adult respondents of age 18 and above. Both descriptive and inferential statistical techniques, such as frequency distribution, bivariate analysis with chi-square test, factor analysis, multiple linear regression and logistic regression analysis were used for data analysis. The study revealed a very high rate of perceived good health status among Omani adults, as 78% of the adults rated their health as good or very good, while only 4% rated their health as bad or very bad and 18% as moderate. Female, elderly adult, people with low level of education, poor and widowed/divorced/separated were more likely to rate their health as bad or very bad. Poor SRH significantly associated with higher prevalence of all chronic diseases as well as higher functional difficulties of health domains. SRH can be used as a health screening tool in the national health care system, and health providers should incorporate it in their clinical practice. Appropriate intervention and policy measure should be taken to improve the health of the sub-groups of people with poor SRH, difficulties, and chronic diseases that have been identified in this study

Biotic and Abiotic Stresses of Major Fruit Crops in Oman: A Review

Oman is located in an arid region of the world that is characterized by adverse climatic conditions, including heat and drought. In recent years, it has also been affected by climate turbulence and the occurrence of severe weather, such as cyclones and heat/cold waves affecting large agricultural areas of the country. Fruit cultivation area represents 31% of the total cultivated area (97,239.58 ha) in the country. However, the production share is only 17% of the total crop production in the country (2.6 million tons). About 90% of the fruit cultivation area is dominated by date palm, banana, lime, and mango. In addition to the abiotic stresses, such as drought, heat, and salinity, major fruit crops have declined in recent years due to various biotic stressors, primarily insect pests, and diseases. For several decades, the date palm has suffered from the Dubas bug and in recent years from Red Palm Weevil. Lime has been infected with Witch’s Broom Disease of Lime (WBDL) caused by ‘Candidatus Phytoplasma aurantifolia’ that has led to the decline of production to 25% from its peak in the nineties. Banana is Oman`s second-largest fruit crop in production and export. It has also been the subject of studies due to losses incurred by farmers during pre-and post-harvest stages, in addition to several pests and diseases that affect bananas in Oman. Mango is another major fruit crop that is primarily cultivated in northern Oman. Severe infection with mango decline has led to the eradication of mango orchards from many regions of Oman, particularly in Batinah Coast, where increased salinity has led to a decline in mango yield. Research conducted in Oman has investigated several aspects of these challenges. This review paper summarizes the outcome from studies conducted in the country and proposes directions towards resolving current and future challenges to the fruit industry

State of knowledge on emergency response and crisis management: evidence of sample secondary students of Bangladesh

In the era of late modernity, individual vulnerability is affected by various threats and risks. Consequently, people need to be aware of these and fit in more than ever before. To help people become competent in this changing world and to prepare for future threats, academic institutions play a vital role. To understand such an academic role, a part of the literature has highlighted how a student can better learn emergency responses (ER) and crisis management (CM). Nevertheless, very little literature has focused on how a developing country’s students, particularly teenagers, learn and understand ER and CM. Focusing on such gaps in the literature, this study aims to understand a sample of Bangladeshi secondary students’ state of knowledge related to ER and CM. With the help of cluster sampling, the researcher distributed a survey among a sample of 360 students between 9th and 12th standard from two southern districts respectively Khulna and Noakhali, which are also disaster-prone areas of Bangladesh. Adopting Krathwohl’s model of knowledge typology, such as factual knowledge, conceptual knowledge, procedural knowledge, and metacognitive knowledge, the researcher collected and evaluated the data with descriptive statistics. The findings of this study show that even though most of the students are familiar with different ER- and CM-related keywords, they have limited deeper knowledge. Furthermore, there was a significant knowledge difference between the genders. Similarly, the lack of training in the academic environment also makes these young students vulnerable to any kind of threat from their surroundings that could affect the districts’ weak institutional and legislative structure. The scholarship of this study, which has policymakers and young academics as its possible audience, could assist them in raising the knowledge levels of students by adding new information to textbooks with illustrations and by setting up drills

Effectiveness of Educational Supervision in Sultanate of Oman as Perceived by Teachers

The study aimed at identifying the effectiveness of educational supervision in public schools in the Sultanate of Oman. To achieve the aim of the study, a questionnaire was designed. It consisted of 49 items distributed into five domains. The domains are: enhancement of instructional and learning processes; school's activities and media; implementation, assessment, and development of curriculum; assessment of instructional and learning process; and teachers’ professional development. The validity and reliability of the questionnaire were examined. The sample of the study consisted of 592 male and female teachers. The results showed that educational supervision in Oman had high effectiveness on enhancement of instructional and learning processes, school's activities and media, whereas, it had medium effectiveness on the other three domains. Based on the results, few recommendations have been suggested

Moment Generating Functions of Complementary Exponential-Geometric Distribution Based on k-th Lower Record Values

The complementary exponential-geometric (CEG) distribution is a useful model for analyzing lifetime data. For this distribution, some recurrence relations satisfied by marginal and joint moment generating functions of k-th lower record values were established. They enable the computation of the means, variances, and covariances of k-th lower record values for all sample sizes in a simple and efficient recursive manner. Means, variances, and covariances of lower record values were tabulated from samples of sizes up to 10 for various values of the parameters