puputyusda apriliana - Academia.edu (original) (raw)

Uploads

Papers by puputyusda apriliana

The threat posed to protected areas by the illegal killing of wildlife is countered principally b... more The threat posed to protected areas by the illegal killing of wildlife is countered principally by ranger patrols that aim to detect and deter potential offenders. Deterring poaching is a fundamental conservation objective, but its achievement is difficult to identify, especially when the prime source of information comes in the form of the patrols' own records, which inevitably contain biases. The most common metric of deterrence is a plot of illegal activities detected per unit of patrol effort (CPUE) against patrol effort (CPUE-E). We devised a simple, mechanistic model of law breaking and law enforcement in which we simulated deterrence alongside exogenous changes in the frequency of offences under different temporal patterns of enforcement effort. The CPUE-E plots were not reliable indicators of deterrence. However, plots of change in CPUE over change in effort (CPUE-E) reliably identified deterrence, regardless of the temporal distribution of effort or any exogenous change in illegal activity levels as long as the time lag between patrol effort and subsequent behavioral change among offenders was approximately known. The CPUE-E plots offered a robust, simple metric for monitoring patrol effectiveness; were no more conceptually complicated than the basic CPUE-E plots; and required no specialist knowledge or software to produce. Our findings demonstrate the need to account for temporal autocorrelation in patrol data and to consider appropriate (and poaching-activity-specific) intervals for aggregation. They also reveal important gaps in understanding of deterrence in this context, especially the mechanisms by which it occurs. In practical applications, we recommend the use of CPUE-E plots in preference to other basic metrics and advise that deterrence should be suspected only if there is a clear negative slope. Distinct types of illegal activity should not be grouped together for analysis, especially if the signs of their occurrence have different persistence times in the environment.

Recently, the need for a more efficient method for ship route planning was raised due to the fina... more Recently, the need for a more efficient method for ship route planning was raised due to the financial crisis in the shipping industry, a strengthening of emission regulations, and the limitations of the existing methods. So far, numerous ship route planning methods have been developed, but most of them do not correctly reflect the effect of a change of the ship speed in the path-determination stage. For this study, a ship route planning problem was formulated as an optimization problem. To solve this, a method for a simultaneous determination of the path and the speed of a ship is proposed. To check the efficiency and the applicability of the proposed method, sensitivity analyses and a comparative test regarding some other methods was performed. The proposed method was applied to various examples of ship route planning and the results show that the proposed method can reduce the total fuel consumption compared with the other methods.

Protected areas are fundamental for conservation, yet are constantly threatened by illegal activi... more Protected areas are fundamental for conservation, yet are constantly threatened by illegal activities, such as cattle encroachment and wildlife poaching, which reduce biodiversity. Law enforcement is an essential component of reducing illegal activities. Although necessary, law enforcement is costly and its effectiveness in the field is rarely monitored. Improving ranger patrol efficiency is likely to decrease illegal activity occurrence and benefit biodiversity conservation, without additional resource implications. Using ranger-collected data, we develop a method to improve ranger patrol allocation, targeting different combinations of conservation priorities, and predict that detections of illegal activities can be greatly improved. In a field test in Queen Elizabeth Protected Area, Uganda, we increased detections of illegal activities in some cases by over 250% without a change in ranger resources. This easily implemented method can be used in any protected area where data on the distribution of illegal activities are collected, and improve law-enforcement efficiency in resource-limited settings.

\Ve consider n points (nodes), some or all pairs of which arc connected by a branch; the length o... more \Ve consider n points (nodes), some or all pairs of which arc connected by a branch; the length of each branch is given. \Ve restrict ourselves to the case where at least one path exists between any two nodes. \Ve now consider two problems.

The threat posed to protected areas by the illegal killing of wildlife is countered principally b... more The threat posed to protected areas by the illegal killing of wildlife is countered principally by ranger patrols that aim to detect and deter potential offenders. Deterring poaching is a fundamental conservation objective, but its achievement is difficult to identify, especially when the prime source of information comes in the form of the patrols' own records, which inevitably contain biases. The most common metric of deterrence is a plot of illegal activities detected per unit of patrol effort (CPUE) against patrol effort (CPUE-E). We devised a simple, mechanistic model of law breaking and law enforcement in which we simulated deterrence alongside exogenous changes in the frequency of offences under different temporal patterns of enforcement effort. The CPUE-E plots were not reliable indicators of deterrence. However, plots of change in CPUE over change in effort (CPUE-E) reliably identified deterrence, regardless of the temporal distribution of effort or any exogenous change in illegal activity levels as long as the time lag between patrol effort and subsequent behavioral change among offenders was approximately known. The CPUE-E plots offered a robust, simple metric for monitoring patrol effectiveness; were no more conceptually complicated than the basic CPUE-E plots; and required no specialist knowledge or software to produce. Our findings demonstrate the need to account for temporal autocorrelation in patrol data and to consider appropriate (and poaching-activity-specific) intervals for aggregation. They also reveal important gaps in understanding of deterrence in this context, especially the mechanisms by which it occurs. In practical applications, we recommend the use of CPUE-E plots in preference to other basic metrics and advise that deterrence should be suspected only if there is a clear negative slope. Distinct types of illegal activity should not be grouped together for analysis, especially if the signs of their occurrence have different persistence times in the environment.

Recently, the need for a more efficient method for ship route planning was raised due to the fina... more Recently, the need for a more efficient method for ship route planning was raised due to the financial crisis in the shipping industry, a strengthening of emission regulations, and the limitations of the existing methods. So far, numerous ship route planning methods have been developed, but most of them do not correctly reflect the effect of a change of the ship speed in the path-determination stage. For this study, a ship route planning problem was formulated as an optimization problem. To solve this, a method for a simultaneous determination of the path and the speed of a ship is proposed. To check the efficiency and the applicability of the proposed method, sensitivity analyses and a comparative test regarding some other methods was performed. The proposed method was applied to various examples of ship route planning and the results show that the proposed method can reduce the total fuel consumption compared with the other methods.

Protected areas are fundamental for conservation, yet are constantly threatened by illegal activi... more Protected areas are fundamental for conservation, yet are constantly threatened by illegal activities, such as cattle encroachment and wildlife poaching, which reduce biodiversity. Law enforcement is an essential component of reducing illegal activities. Although necessary, law enforcement is costly and its effectiveness in the field is rarely monitored. Improving ranger patrol efficiency is likely to decrease illegal activity occurrence and benefit biodiversity conservation, without additional resource implications. Using ranger-collected data, we develop a method to improve ranger patrol allocation, targeting different combinations of conservation priorities, and predict that detections of illegal activities can be greatly improved. In a field test in Queen Elizabeth Protected Area, Uganda, we increased detections of illegal activities in some cases by over 250% without a change in ranger resources. This easily implemented method can be used in any protected area where data on the distribution of illegal activities are collected, and improve law-enforcement efficiency in resource-limited settings.

\Ve consider n points (nodes), some or all pairs of which arc connected by a branch; the length o... more \Ve consider n points (nodes), some or all pairs of which arc connected by a branch; the length of each branch is given. \Ve restrict ourselves to the case where at least one path exists between any two nodes. \Ve now consider two problems.