The Impact of Uncertainty Factors on the Decision-Making Process of Logistics Management

The article is a contribution to the discussion on the possibilities of effective logistic decisions under the conditions of uncertainty. Variable and unpredictable factors, which create the conditions of uncertainty, not only directly affect logistic processes (positive or negative impact), but can also be a determinant of making decisions. Logistics management, because it is referred to in the context of decision-making, is currently defined by the quality of management decisions taken, including factors which often constitute only partially quantifiable sets. The main goal of the article is to show the strength of the dependence between the occurrence of uncertainty factors and the type of decision. On the basis of decision-making theory, the types of decisions were defined, and then a set of factors that are most important for a given type of decision was selected. The results of the analysis allowed the strength of the influence of uncertainty factors on making logistics decisions to be determined. On this basis, a catalog of key decisions was selected, including decision types, and also the effects of decisions taken under uncertainty were determined. The study and the results of the analysis should be treated rather as a voice in the ongoing discussion. Due to the unpredictability of some uncertainty factors, the research field in the discussed problem remains open.

SISTEM PAKAR PENDIAGNOSA PENYAKIT ANAK MENGGUNAKAN CERTAINTY FACTOR (CF)

SISTEM PAKAR PENDIAGNOSA PENYAKIT ANAK MENGGUNAKAN CERTAINTY FACTOR (CF)ABSTRAKTelah dibangun sistem pakar untuk mendiagnosa penyakit anak dengan penanganan faktor ketidakpastian menggunakan certainty factor (CF). Tahapan pembangunan sistem ini dimulai dengan mengakuisisi pengetahuan dari dokter ahli anak kemudian membangun basis pengetahuan dan memberikan nilai CF pada setiap gejala yang terkait dengan suatu penyakit anak dalam range nilai 0 dan1. Dengan memilih gejala-gejala penyakit yang dilihat atau dirasakan maka sistem dapat mendiagnosa penyakit anak dengan menampilkan tiga penyakit dengan nilai CF terbesar yang diurutkan secara descending.Kata kunci : Certainty faktor, sistem pakar, penyakit anak EXPERT SYSTEM FOR DIAGNOSING CHILD DISEASE BY USING CERTAINTY FACTOR (CF)ABSTRACTAn expert system has been conducted for diagnosing child disease by using certainty factor (CF) with uncertainty variable. This conducting phase was started by acquiring the pediatrician’s knowledge which was then followed by conducting knowledge base and giving CF value on every symptom which bonds to a child disease on 0 to 1 range. By choosing the syptoms of the disease that have been observed or felt, the system would be able to diagnose the child disease by showing the three diseases which have been listed descendingly from the biggest CF value.Keywords: certainty factor, expert system, child disease

Assessment of the Uncertainty in Corrosion Models for Ship Steels

The corrosion model proposed by Melchers (2003) is compared with the one of Guedes Soares and Garbatov (1999) for a range of parameters that is considered representative of the situations to occur in corrosion of ships and offshore platforms. The differences in the model predictions are represented by a model uncertainty variable and the bias and uncertainty is determined for representative corrosion periods of 7, 15 and 25 years. Is concluded that the average bias is generally within 10% and the standard deviation is of the order of 10% for periods of the order up to 15 years. For shorter durations even better correlations are obtained. For durations of the order of 25 years the mean bias can go up to 20% in limit conditions although in the most common situations it is within 12%.