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Wildfires, occurred in transmission line corridors, seriously affect the security and stability of power grids. In order to reduce the effects of wildfire on power grids, a logistic regression (LR) model was employed to assess the risk distribution of wildfire occurrences in transmission line corridors. Guizhou Province which locates at south-west of China was taken as the study region. An inventory dataset of Guizhou Province including 14 wildfire-related variables and historical wildfire occurrences were assembled. After the multicollinearity analysis of wildfire-related variables, the occurrence probability of wildfires in the study region was calculated by the LR model. And a wildfire risk distribution map was drawn in a resolution of 1 km × 1 km for visualization. The wildfires happened from January to May 2020 was applied to the validity of wildfire risk distribution map. The results shows that 82.65% of fire points were happened in the area with the third and fourth risk level. It indicates that the proposed method can be used to provide technical support for the maintenance staffs to carry out differentiation technology and strategy for wildfire protections.

This thesis transforms the choice of marching route into risky two-level decision-making by analyzing feasible alternative routes, road conditions and their occurrence probability. Based on the decision tree method, the thesis depicts a two-level decision tree of marching route. After calculating the expected marching time along each alternative route, the thesis identifies two-level optimal marching route based on the minimal expected loss criterion. The result of example analysis proves that the method is effective, and describes the process of multi-level decision-making of marching route in a clearer way.

In recent years, bird damage has become one of the major hidden dangers of power grid security. How to reduce the harm of bird activities to power equipment and promote the harmonious coexistence of human and birds has become a new social topic for power grid enterprises to carry out transmission line operation and maintenance work. Due to the wide distribution area of transmission lines, it is a waste of human and material resources to drive away birds blindly, and it needs a long time to adhere, so it is difficult to effectively prevent bird damage. Therefore, the prediction of the probability of bird damage is a powerful tool which can effectively reduce bird damage. This paper provides an effective method to predict bird damage. Firstly, the effects of topography, surrounding environment, voltage class, tower type, wire arrangement and season on bird damage are analyzed respectively. Then, multiple linear regression is used to establish the model between the occurrence probability and characteristic factors of bird damage, and correlation coefficient is used to evaluate the accuracy of the model. Experimental results show that the proposed model has high accuracy and reliability.

In this paper, we present a novel imaging strategy of SAR for ship detection. We firstly divide surveillance area into many adjacent cells. By introducing Bayesian approach, the target occurrence probability of each cell is obtained. Based on the probability, a target-searching strategy is proposed and interest cells are determined for SAR imaging. This imaging strategy only images regions where target-presence probability is high. Reduction of imaging in no-target areas promises this novel imaging strategy more efficient and low time cost.

Raising the speed of high-speed railway train provides great convenience for people to travel, but once an emergency occurs, the consequences are incalculable. Because of the uncertainties in the development process of railway emergencies, emergency decision-making often needs to be adjusted according to the changes of the state of the incident, that is, dynamic adjustment. Aiming at the dynamic adjustment of railway emergency plan, the emergency decision-making process is divided into several stages according to the key nodes. At each stage, the perceived utility value under the combination of the corresponding scheme and the scenario is obtained, and the utility risk function is derived by combining the utility value with its occurrence probability. Considering the utility risk under different situations of the same scheme, the utility risk entropy of the emergency response scheme is obtained, and the best scheme at the current moment is selected. Finally, an example is given to verify the effectiveness of the proposed method.

Due to technical trends requiring high memory bandwidth, the number of output buffers is increasing which generates non-linear power/ground noise associated with simultaneous switching output (SSO). However, the SSO also causes fluctuation in output responses of buffers remaining in steady states. In this paper, for the first time, impacts of SSO buffers on steady state output responses and signal integrity of high-speed channel are analyzed based on statistical method. Output step responses not only for pull-up/down transitions but also steady states affected by SSO are obtained using transient simulator. Then, occurrence probability of each SSO combination is mapped to corresponding output response to generate output response probability density functions (PDFs). Using the derived PDFs statistical eye-diagrams are derived to validate the impacts of SSO on overall shape of the eye-diagram. Finally, the proposed method is compared with conventional statistical method.

Inter-radar interference of densely deployed automotive FMCW radars can cause miss detection and/or false detection of the target, i.e. ghost target detection. As the occurrence probability of narrowband interference is relatively large in fast chirp FMCW radars, this paper proposes a novel concept of packet-based FMCW radar using CSMA (Carrier Sense Multiple Access) technique to mitigate narrowband interference of FMCW radars. This paper defines available frequency resources for the packet based FMCW radars and proposes two CSMA schemes, i.e. single carrier sense based CSMA scheme and double carrier sense based CSMA scheme for packet based FMCW radars. It also evaluates narrowband interference mitigation performance of the proposed packet based FMCW radars using CSMA by computer simulations.

As a result of the increasing share of distributed generation in electric supply, the probability of unintentional electrical islands is also increasing. Unintentional islands occur when sub-grids with balanced active and reactive power are separated. Stable unintentional islands are hard to detect and pose a risk for normal grid operation as well as in the case of grid faults. This paper presents a novel method to estimate the occurrence probability of unintentional islands before a grid disconnection occurs. For this purpose, active and reactive power at potential disconnection points and additional information about electrical loads or distributed generation are determined and evaluated. This method can also be used to predict the development of the unintentional island probability. With the knowledge of possible electrical islands, preventive measures can be taken. A specific procedure for reactive power adjustment, based on the islanding prediction, is presented.

With the strengthening of the awareness of environmental protection, the pollution of the water area by vessels and their related activities has attracted more and more attention.In this paper, the source term analysis of accident risk sources and the establishment of risk assessment standards are carried out. Taking Hunan Province as an example, relevant data of the recent 10 years are collected through field investigation, and the accident occurrence probability and accident pollution amount of Hunan Province and other cities and states are studied.At the same time, the accident risk levels of Hunan Province and other cities and states are calculated, and relevant countermeasures are proposed for the medium high risk areas.

Civil aviation flight accidents are commonly recognized as low probability events. For the purpose of rational assessment of flight accident risk, information diffusion technique is adopted to develop the risk analysis model for flight accidents. To demonstrate its applicability, flight accident numbers of the latest 10 years (2008-2017) of China are selected as observation samples, and flight accident risk is calculated by using the proposed model. Analysis of the result shows that the number of flight accidents ranged over a big span. The 4 highest occurrence probability of flight accidents are 3-6 times per year (P>0.08), however it is quite rare that the number of China air transportation accident is large than 10 (P=0.2426). In average, there is about 6 flight accidents per year. The model provides a way for the estimation of flight accident risk which will contribute to civil aviation safety decision-making.

Study of the sporadic Es layers occurrence probability based on the ionospheric oblique sounding data was carried out. The methodology of reflections from the regular E and sporadic Es layers separation based on the oblique sounding data was developed. The probability of sporadic Es layers occurrence on high-latitude radio paths under different geomagnetic perturbation conditions was assessed.

This work analyzes the occurrence probability of the Z-component trace on topside-sounding ionograms in the experiments aboard the Interkosmos-19 satellite and the space station Mir. The orbit height of Mir was around 350 km, while the perigee and the apogee of Interkosmos-19 were at 500 km and 950 km from the Earth surface.

This paper investigates the Random Telegraph Signal (RTS) in Single Photon Avalanche Diodes (SPADs). The test-chip features SPADs with different architectures implemented in 150 nm CMOS technology. The test-chip has been irradiated with 21 MeV proton beam. RTS occurrence probability has been investigated in two different architectures. RTS measurements allowed to investigate the defect responsible for RTS phenomenon.

The need for protecting information stored in the personal computer prompts the development of masquerade detection system (MDS) which raises an alert whenever it detects an anomaly in user behavior. The audit log analysis of local access to files is an effective way to detect masquerader. Due to privacy limitations of file content, most file based detection algorithms mainly focus on the file paths. These methods either formulate the file paths as multiple local features and then input into the classifier, or compare the current file paths with the past ones. However, few works take file actions into account, such as delivering the file to the external drive. By contrast, in this paper we simultaneously consider the file actions and the file paths, and propose a MDS based on the temporal and spatial analysis of file access records (TempatMDS). On the one hand, spatial analysis concentrates on the file path and models path relationships between files accessed in different periods of time, called sub-activity in this paper, as a file access network. Then activity classes are extracted from the network to indicate the user's assignments and the anomaly score of sub-activity is defined as negatively related to the closeness of sub-activity with the activity class. On the other hand, under the assumption that the user usually accesses certain files depend on current assignments in a repetitive way, temporal analysis constructs the file actions sequences from sub-activities, and formulates the anomaly score of sub-activity as negatively related to the sequence occurrence probability. Finally, the ultimate detection result is determined by fusing the anomaly scores from the spatial and temporal analysis in a robust manner. The effectiveness of TempatMDS is clearly demonstrated by its excellent performances on a collected dataset, involving the real file access records from 10 users in our lab and attack data simulated by impersonating the genuine user, in comparison with state-of-the-arts.

Internet threat monitoring (ITM) has been exten­sively performed by several organizations. To effectively analyze and grasp the trends of various security threats on the Internet, efficient analysis and event detection from traffic observed by ITM systems are desired. This paper reports the first attempt to adopt a network-state evaluation method which focuses on the occurrence probability matrices of the correlation coefficient of traffic observables for event detection in traffic observed by an ITM system.

The causes of decametric radio emission from Jupiter and their activities have considered at length. Some remarkable effects about the satellite Io of Jupiter and non-Io related sources responsible for decametric emissions as recorded in our observatories at Kalyani (22.97° N, 88.43° E) and at Kolkata (22.58° N, 88.42° E) at 20.1 MHz for the period from January 2011 to March 2015 have been critically examined. The probability of detecting radio sources A, B, and C against Jupiter's Central Meridian Longitude (CML) have taken into consideration. We have examined the occurrence probability against Io phase and CML and also plotted the year vs. average duration of presence of Jupiter in West Bengal sky for the years 2011 to 2015, showing that the Jupiter is in declining phase in the northern hemisphere. A comparison of the occurrences of Io and non-Io events of all the three categories during spring, summer, autumn and winter have then been made, analyzing the probability of occurrences of Io related and non-Io related events during the four seasons. Finally some typical records have been chosen to illustrate the characteristic variations of the received radio signals associated with different types of events.

To achieve workflow retrieving and compliance checking based on behavior, it is necessary to identify the behavioral profiles of workflow models. Since the execution timing and the occurrence probability of tasks are crucial to choose appropriate workflows, it is significant to conduct exact quantitative analysis on the ordering relations by considering the time constraints and occurrence probabilities of tasks in workflow models. In this paper, the quantitative ordering relations are formally defined and an algorithm is proposed to efficiently compute the ordering relations with time and probability constraints based on complete firing sequences. Experiments show that the algorithm works well. Refereed/Peer-reviewed

Increasing redundant paths in transmission grids has always been thought to be a tool to enhance service reliability. However, network equations by intertwining power flows through redundant paths impose more limits on systems with more redundancy. Accordingly, autonomous removing of a few lines may relief capacity limit violations in some contingency events thereby enhancing service reliability. This paper aims to study impacts of manual removing of transmission lines on composite system reliability. For doing so, the existing model is extended to consider optimal transmission switching (OTS) as a remedial action. The model minimizes total damage cost imposed by load curtailments. The extended model is formulated in mixed integer linear programming (MILP) format that can be easily solved via commercial solvers. The model is applied to likely contingencies wherein violations in capacity limits are encountered. Then, the results along with occurrence probability of the contingencies are taken into use to calculate load point and system oriented reliability indices. Simulation results on the modified reliability test system (MRTS) demonstrate great enhancements in service reliability when OTS is realized.

Green Light Optimized Speed Advisory (GLOSA) systems aim at giving ideal target speed recommendations to the driver when approaching a traffic light to lower CO 2 emissions (and fuel consumption) and to reduce the number of unnecessary stops. These systems have been shown to work well with static traffic light programs, unfortunately, a large portion of traffic lights in inner cities are adaptive and can change their behaviour with almost no lead time. This paper presents and validates (using field tests and simulation) a method to help overcome this problem and forecast fully and semi-adaptive traffic lights. First, we transformed the state graph of the traffic light controller into a transition graph focusing on signal changes and their occurrence probability. We then reduced routing possibilities within the graph using real life observations and recorded detector data of the traffic light. We further optimized our system in terms of needed storage and computationally efficiency. Our results show that in 80% of all cases we could predict signal changes 15s in the future with a high enough accuracy to enable GLOSA for adaptive traffic lights.

Since finding and extracting a fixed signature for metamorphic viruses is hard due to the fact that, their shape changes frequently. Virus writers by using obfuscation methods make their viruses undetectable, in order to disable anti viruses to detect them easily, which ends in metamorphic viruses. We used hidden Markov model to propose the Detection Sphere method. We used three elements of a string occurrence probability, specifically-located character occurrence probability, and the amount of virus similarity to a family of viruses. The 94% detection rate result is magnificent in contrary to other anti-viruses which are less than 30%. More research and investment in multi-factor methods in hidden Markov model are recommended to detect viruses and malwares.

Sporadic E (E s ) layers have been detected by an ionosonde during 2008 to 2011 at Qingdao (36°N, 120°E), China. At the same time, we have observed nocturnal Na layers by a lidar with a horizontal distance of only ∼30 m away from the ionosonde. In order to study the correlation between the occurrences of E s and sporadic Na (Na s ) layers, we can compare the E s occurrence rate during the period of Na s layers with that during the entire observation period of Na layer. It should be noted that the E s occurrence rate during the observation period of Na layer could be different with the nighttime mean E s occurrence rate. Based on the four years simultaneous and closely colocated observations at Qingdao, it is found that the temporal coverage of Na data possessed remarkably seasonal and nocturnal distribution asymmetry. Consequently the E s occurrence probability during Na data period (11%) was different with the nighttime mean E s occurrence probability (20%).

In this paper, the reliability prediction approaches and flowchart based on PoF(Physics-of-Failure) of mechanical structure and system under multi-mechanism are discussed. Nowadays, the structure and load condition of mechanical products become more and more complicated, and the failure mode becomes more difficult to identify. It is necessary to use PoF method to build model and analysis failure problem. In the method, the effect of factors and interaction between different failure modes are considered, the stochastic PoF model was used to simulate and analysis reliability, predict the occurrence probability of the failure, and the correlation between two failure modes is given, the reliability index and the lifetime etc. are given also.

Vehicle speed control is one of the main methods to ensure the safety of freeway work zone. In order to control vehicle running speed reasonably in freeway work zone, the research of adaptive speed control of freeway work zone is carried out. Based on the analysis of the speed change law of the vehicles nearby freeway work zone, combined with the electronic sensor technology and data transmission technology, an adaptive vehicle speed control measure of freeway work zone based on ITS is proposed. Then the theoretical framework of adaptive speed control measure in freeway work zone is built, and the effectiveness validation of the solution is taken. The measure could decrease the speed difference between the upstream and downstream vehicles, as well as reducing the occurrence probability of traffic accidents such as rear-end. Meanwhile, it can effectively improve the traffic capacity of freeway work zone on the premise of ensuring safety.

Freak wave may cause danger to ships or people who active at coastal area. Prediction of freak wave can provide early alarm information and hence reduce risks of hazards. However, due to the unclear of freak wave mechanism, deterministic prediction is not possible but stochastic method can be used for research of occurrence probability of freak waves. In this study, nonlinear wave theory is considered for derivation of freak wave occurrence probability. It is function of number of waves and kurtosis of water elevation. Field data from long-term measurements were used for validation which demonstrates the existence of bias. The average root-mean-square-error is 22.4% which is acceptable.

In power systems the occurrence probability of operating points close to network limits may be increased as a result of high wind penetration. Consequences of such scenarios include inefficient exploitation of both wind and economic resources. A well chosen allocation of wind capacity not only is in line with the trend of renewables integration in power systems but also allows for limiting the occurrence probability of unsafe operating points that may require costly remedies. In this work, a voltage stability constrained optimal power flow (VSC-OPF) framework is presented for transmission system planning and applied to wind capacity allocation. This framework captures multiple wind and demand scenarios within the OPF. The pattern of wind capacity allocation is studied in order to assess its impact on voltage stability and the total wind capacity allocation. The results emphasize the effect of the capacity allocation pattern on improvement of voltage stability.

Point mutations in conserved gene sequences are used as the trace marker for determination of evolutionary distance among the species. Novel method is based on calculation of nucleotide occurrence probability in fixed size moving window and determination of high order central moments. Description of nucleotide occurrence probability can provide high accuracy point mutation detection, and the insight into local sequence.

According to many gas leak investigation statistic data, the occurrence probability of several objects or devices, e.g., tank or valve, is very high. In other words, Visual information plays an important role in gas source localization. In this paper, a simple and robust object detection technique for locating the suspicious gas sources is proposed. The scale invariant feature transform (SIFT) descriptor is invariant to image translations, rotations, scale changes, and robust to illumination changes. Numerous evaluation tests have been demonstrated that the robustness and repeatability of the SIFT descriptor outperforms other methods. Therefore, we use SIFT feature matching method to detect plausible gas sources. Experimental results show the efficiency and practicality of the approach for localizing a leaking ethanol bottle in complex indoor environments.

We found that the discrepancy between different finger vein templates of the same finger affects the identification results more seriously than the similarity of templates of different fingers does. Some areas on templates have stable values while some other areas are variable. We propose the Occurrence Probability Matrix (OPM), which is a property of a finger, to define the stability. When matching two templates using OPM, the areas of higher stability make more contribution to the result and those of lower stability make less contribution. In this way, OPM can enhance the similarity of templates of the same finger and drop off the influence of the unsteady areas. In a finger vein verification system running for a long time, we can get enough templates of every finger to generate an effective OPM. But it does not mean that using more templates can get a better OPM. So, we fatherly propose a strategy to select typical templates purposely from all templates of a finger to calculate the OPM. Experimental results show that by simply using OPM calculated from all existing templates, the EER of the system is reduced from 9.8% to 7.6%. And by using the OPM calculated from selected typical templates by our strategy, the EER of the system is further reduced from 7.6% to 3.1%.

Transport safety is a serious issue of today's society. Hence investigating the effects of accidents and the interventions of reducing the negative impacts are of global interests as well. Based on mathematical, economic probability theories, our research provides an appropriate model for this purpose.

Fault tree analysis (FTA) is a popular methodology for system reliability analysis. The occurrence probability of the basic event is accurate in traditional fault tree (FT). Owe to the lack of the reliability data, especially in early design stage; a large amount of uncertainties may be included in FTA. In this study, the Dempster-Shafer (D-S) evidence theory is employed to quantify the uncertainty of the FTA and to aggregate the different evaluation information of multiple experts on the occurrence probability of basic event. The evidential network (EN) is used to propagate the uncertainty in FTA. The FT of the aero-engine damage caused by low pressure of lubricating oil is analyzed.

This paper presents an investigation of a research project titled “Innovative Seating Systems” by BMW Group “Research and Technology” Team. It is based on my idea and reports about “Benefits of using Bionic Seats in Roadster cars” which is submitted and accepted by BMW Group Co-Creation Lab in March 2010. In this paper, three BMW Group revolutionary innovative seating systems, Bionic Seat, Ergo Seat and Formfitting seat Space Comfort Shell will be investigated in terms of comfort and safety. They will be studied and examined by various virtual applications to visualize their reactions and finally be judged. These three conceptual seats will be utilized and tested by current massaging systems, Active and Passive Safety options as well. Moreover, whiplash effect during rear impact and its occurrence probability would be calculated.

The location information is very essential to monitoring activities in wireless sensor networks. According to the low accuracy of IAPIT-3D (Improved Approximate Point in Tetrahedron) in beacon-sparse environment, we propose a RSSI-weighted refinement method. It reduces the occurrence probability of the “in-to-out error” by utilizing the improved GRID SCAN. Moreover, the RSSI-weighted method improves the accuracy and decreases the probability of “in-to-out error” simultaneously. The simulation reveals that this method enhances the accuracy relatively to IAPIT-3D and is robust to the low node density.

In order to achieve effective fault injection and support the fault diagnosis verification for PHM (Prognostics & Health Management), a method for importance analysis of failure mode based on EDA simulation is introduced. In this paper, the influence factors of failure mode importance (Effect Severity Ranking (ESR); Occurrence Probability Ranking (OPR); Detection Difficulty Ranking (DDR)) are reasonable described. And based on the EDA simulation, the method for importance analysis is explicated with certain circuit in PHM system. It is validated that the presented method can meet the demands of importance analysis. The presented method can increase the precision of importance analysis, deduce the time cost of analysis, and will be significant to implement the fault injection and fault diagnosis verification for PHM system.

With the aim of extending the method in recommendation ITU-R P.452, this paper derives a new clutter loss calculation method, which yields losses for given occurrence probabilities. We use the knife-edge model to derive a new relation between the clutter losses and occurrence probability, the only essential parameter is the average building height in the area being investigated. The proposed method also makes it possible to take frequency characteristics into account. Numerical examples are given and their results are compared to the clutter losses output by the current method in P.452.

Aiming at the defect of traditional Risk Priority Number(RPN) method in FMECA, a RPN assessment method is put forward which bases on the fault propagation probability and cost, then a corrective actions choice method is presented by gray correlation theory. Firstly, the occurrence probability and cost are calculated according to fault propagation tree. RPN is assessed by the overall risk of the events. This method avoids the subjectivity and inaccuracy of O,S and D' ranking assessment in traditional RPN. Then a gray correlation theory is introduced in to implement corrective actions choice for the failure mode whose RPN value is higher than the acceptable risk. The choice method has made up for the lack of corrective actions choice method in traditional RPN. Finally, an aircraft elevator control sub-systems is taken as an example and RPN assessment method and actions choice method above are used, a better result is obtained.

Although an improvement of hierarchical text classification can be achieved by using hierarchical structure information, existing hierarchical text classification methods suffer from a problem, namely error propagation (especially in large-scale deep hierarchy). In this paper, we define the concept of path-based semantic vector for the presentation of categories based on which prior information provided by training set can be employed in a classifier-independent way to reduce and further eliminate classification errors. In particular, we first propose the occurrence probability based strategy for hierarchical text classification which can help limit errors rate efficiently. Cooccurrence probability is then introduced to correct the classification errors occurred on higher levels of the hierarchy. Extensive experiments show that our hierarchical classification strategies perform well on ODP dataset, even on deep levels of the hierarchy.

In this paper some basic considerations about risk management should be given. The definition of risk implies the terms damage and occurrence probability. There were different kinds of risks known which can be partitioned in technical, economical or juridical reasons. For the evaluation of assets in utilities normally the technical and economical risks were dominant, juridical risks due to contracts and customer claims were secondary in our days.

Since the various industrial accidents have been occurring because of increasing of industrial production and complication of a production system, the demand to introduce the safety system is increasing greatly. In the light of the above background, development of new EMC standard for safety systems is advanced in IEC. This standard is intended to quantify occurrence probability of the dangerous condition resulting from EMC and to provide EMC requirements for the IEC standards of the functional safety. In this paper, we discussed the basic EMC concept for safety systems and the requirement of immunity level in the new IEC standard.

In this paper, we discussed the methodology of multi layers defect monitoring using probability of occurrence (p) instead of average value. We also show how the probability of occurrence (p) is able to early trigger a defectivity event thus preventing major yield impact compare to average value.

Traditionally, step-by-step procedures determine the way in which tasks must be carried out. Safe work procedures include measures that tend to decrease or eliminate the hazards stemming from the execution of a job, with the workers and the company committing themselves to efficiently preventing accidents at work. Given the great number of tasks involved in the area of distribution, it is necessary to establish critical tasks on the basis of their potential for causing accidents. Therefore, aspects such as severity of damage, frequency of exposure, hazard assessment, probability of occurrence, means of protection, and personnel qualifications & training are fundamental when trying to determine critical tasks. They are also the basis for developing safe work procedures. This research work shows how C.A. La Electricidad de Caracas reinforces safety in its processes and redefines its work procedures according to the Safe Work philosophy.

This paper proposes a systematic evaluation of on-demand failure of protective systems. For a protective system to perform its function, the protective system must satisfy the following requirements: (1) the availability of the protective system, (2) the detection of a plant failure, and (3) the selection of an appropriate protective action, and (4) the performance of the specified protective action. If any one of the requirements is not satisfied, the protective system gets failed. Based on the accident occurrence probability, the improvement of maintenance policy and the re-design of independent protective systems can be considered. An illustrative example of a simple reactor system with several protective systems including operator actions shows the details of the proposed method.

In this paper the influence of a contingency in the series compensation (SC) device allocation and size is evaluated. The SC placement and size are determined using an optimal power flow (OPF) program via the Benders cut technique to include the contingency influence. This problem is solved in two steps: (i) The SC size and placement are determined as an investment OPF subproblem. The SC cost and energy production cost are included in the objective function; (ii) The operation OPF subproblem is solved considering the specified line and generation outages. The Benders cut are generated according to the outage occurrence probability. In this case the objective function is the minimum load shedding and energy production cost. The OPF subproblems are solved using linear programming technique. The IEEE-14 bus and IEEE-118 bus test systems are used to show the effectiveness of the proposed methodology.

In this paper, an information criterion for discriminating two events is proposed. The proposed information criterion is defined by considering the occurrence probability of events. Properties of the criterion are investigated and the criterion is applied to the evaluation and factor selection of the previously proposed discriminant analysis.

The optimum islanding preventing method for the small scale dispersed PV system were evaluated, based on a simulation analysis concerning the occurrence probability of islanding phenomenon in actual operation. As a result, it is sufficient to adopt only one developed measure when the PV penetration ratio to distribution line capacity is less than 20% to 30%. It is necessary to adopt a combination method consisting of 2 or more developed measures when the penetration ratio is more than 40%. The harmonic monitoring method is effective in the case of using it in a combination method.

Assembly techniques using flip chip devices on PWB and ceramic have been available for several years. When Medtronic Micro-Rel decided to introduce this technology or change some of the design, component, or process parameters, failure modes and effects analysis (FMEA) proved to be a useful tool to identify any potential design and process related failure modes. Additional purposes of an FMEA are: to determine the effects of the failure modes; to determine the root cause of the failure modes; to prioritize actions using a ranking system for failure mode effects in terms of failure mode occurrence probability, failure mode effect severity and failure mode detection probability through manufacturing; to identify, implement, and document corrective actions to address failure modes with rankings that are considered unacceptable. The purpose of this paper is to address FMEA by dividing the process into smaller pieces for manageability. Also, this report addresses preliminary FMEA performed early in the evaluation stage of flip chip devices on PWB. Many initial inputs were based on available literature, and many of the evaluations and designed experiments (DOE) performed were driven by the initial FMEA rankings. During development, six DOEs were recorded and performed, addressing various issues related to flip chip attachment. Areas reviewed included solder screening, reflow profiles of the flip chip dice, and underfill dispense parameters. The FMEA was then reevaluated after all evaluations and qualification builds were performed. These findings were used to drive design rules and process parameters.