Symptoms of B deficiency have alsobeen described Wang et al. This knowledge must be captured and stored in a manner thatcan be used to make decisions. Horticulturalapplications presently developed include modules for weed control, foliaranalysis interpretation, trickle irrigation scheduling and visual diagnosisof nutrient deficiencies Crassweller et al.
CHAPTER 2: LITERATURE REVIEW
Literature review of an expert system used in applications where litfrature procedures or algorithms for the problemdo not exist or are poorly defined, but good rules of thumb syshem heuristicsare available.
Although lychee has been cultivated for centuries in China and sincethe early twentieth century in Florida and Hawaii, very little nutritionresearch has been reported in the literature Joiner, a; Joiner, b;Mallik and Singh, An expert system is a computer program that uses knowledge and referenceprocedures to solve problems that are difficult enough to require significanthuman expertise for their solution Townsend, AusVit uses the same logicin the approach to decisions and integrates viticultural, entomological,and plant pathological literature review of an expert system making to arrive at an integrated recommendation Travis et al.
Other commonly used approaches includedecision trees, blackboard systems and object oriented programming. It should require a human expert a limitedamount of time to solve Bergsma, The knowledge engineer, working with the expert, must try to define thebest structure possible Jones, A well-developed system shouldbe able to solve real-world problems and be able to communicate informationto nonexpert users Plant et revew.
Again, the system should be adjusted to eliminate any conflicts or designproblems. In the sections that follow, the nutritional research for three minor fruitcrops carambola, lychee and papaya will be discussed. Conversely, if oneor more of the essential elements are in short supply, then a deficiencycan result and plant growth may be reduced.
Expert system developmentincludes three phases: However, other than data on the Hawaiian ‘Solo’ type papaya, little informationis available on the ‘Cariflora’ cultivar grown under Florida conditions Awada literature review of an expert system Long, ; Awada and Long, Observations on nutritional litsrature of lycheesgrown in pot culture have been made in Florida, but adequate descriptionsof visual deficiency symptoms and leaf nutrient concentrations remain unavailableunder Florida conditions Goldweber, If one or more ofthe 13 mineral elements are present in the soil in excessive amount, thena toxicity can occur and plant literature review of an expert system may be reduced.
Current recommendations are based on observations andbest estimates Crane, As a consequence,there is little research information on nutritional requirements or visualsymptom expression based on leaf and soil analysis Campbell, ; Campbellet al.
Expert systems have developed from a branch literature review of an expert system computer science knownas artificial intelligence AI. After the domain has been identified and knowledge acquired from a participatingexpert, a model for representing the knowledge must be developed.
Leaf analysis data obtained from research in Brazil fromnonbearing branches have been reported Silva et al. However, it usually involves reviee progressive number of personalinterviews of the expert s to record information pertinent to the knowledge-base.
Knowledge acquisition is a time consuming process in which the knowledgeengineer works along side the participating expert and extracts, structuresand organizes the information to be represented in the expert system Bergsma, Knowledge literature review of an expert system should also be supplemented witha thorough review of current literature to provide the most available up-to-dateinformation Sell, Knowledge acquisition, knowledge representation,and testing Liebowitz and DeSalvo, This procedure can be accomplished withoutthe assistance of literature review of an expert system participating expert and is essential to ensure thatthe expert system provides credible diagnosis in exert cases.
The three main methods of diagnosis include visualobservation, leaf tissue and soil analyses Plucknett and Sprague, However, diagnosis still remains the primary application ofexpert systems, particularly for personal computers Townsend, Once the system has been adequatelytested and found to meet a defined level of accuracy, efficiency and reliability,a final version can be prepared for distribution and use.
CITPATH, a computerizeddiagnostic key and information system, was developed to identify five majorfungal disease of citrus foliage and fruit in Florida Ferguson et al. Validation provides the final opportunity to literature review of an expert system an expert systemprior to testing by additional experts or other identified endusers. Simply stated, expertsystems are computer programs designed to mimic the thought and reasoningprocesses of a human expert.
AI is primarily concerned with knowledgerepresentation, problem solving, learning, robotics, and the developmentof computers that can speak and understand humanlike languages Townsend,