Untangling process complexity in logistics delivery services with unpredictable service sequences: a mixed-method study of chemical tanker port calls

We explore the complexity issue relevant to a logistics service process characterized by unpredictable service stages and service sequences in the context of chemical tankers’ call in the Port of Houston. The operational dimensions of uncertainty and conflict surrounding process complexity are examined through a mixed-methods approach using both qualitative and quantitative data collected from the Port of Houston. We propose a taxonomy to classify several uncertainty and conflict factors emerged from our qualitative analysis, including structural conflict, structural uncertainty, infrastructural conflict, and infrastructural uncertainty. The case study findings are validated and triangulated by a quantitative analysis which quantifies the time and cost impacts of unproductive chemical tanker movement on port-call service performance. We contribute to the complexity theory by introducing four dimensions of process complexity to the stream of process-oriented logistics service research. These four complexity dimensions can be used by managers to untangle their process complexity. Our pseudo-service-stage based mapping technique will also be valuable for managers to visualize their service processes with unpredictable service sequences. Finally, we call for future research on synchronization across operational processes between service stages.     

Environmental Protection in Coastal Recreation Sites in Antalya,Turkey

This study was designed to evaluate different approaches to the protection of the environments of coastal recreation sites in and around Antalya, Turkey. Data was collected by means of a survey of coastal recreation sites and six categories were evaluated: environmental protection, infrastructure facilities, water conservation, energy conservation, waste management, and protection of the natural environment. The results indicated that there was a clear motivation among site managers or authorities for environmental protection (p < .05), infrastructure facilities (p < .001), water conservation (p < .05), energy conservation (p < .05) and the protection of the natural environment (p < .001) but waste management was not accorded a priority. The quality of coastal recreation largely relies on the attractiveness and naturalness of the environment. Although good quality site management largely depends on the awareness and willingness of individual site managers, more proactive approaches toward better environmental protection of recreation sites along the Turkish Mediterranean coast might be effective in improving their sustainable use, particularly in the absence of proper site planning.     

Environmental protection motivation in coastal zone land‐use legislation

Abstract

Analysis of recent substantive coastal land use management laws shows that their main thrust is to provide for protection of the coastal environment from adverse impacts of uncontrolled development. The four purposes cited most frequently among laws of 17 states were: Protection of wildlife and fisheries, protection of ecosystems or the natural environment, control of development, and enhancement of esthetic values. Other purposes were to: Protect life and property, enhance public recreation, conserve soil, and protect water resources. Development and economic purposes were cited in relatively few laws.     

Valuing Recreation and Amenities at San Diego County Beaches

Abstract

Policymakers and analysts concerned with coastal issues often need economic value information to evaluate policies that affect beach recreation. This paper presents economic values associated with beach recreation in San Diego County generated from a recreation demand model that explains a beach user's choice of which beach to visit. These include estimates of the economic values of a beach day, beach closures, and beach amenities.     

An empirical model for estimating berth and sailing times of mega container ships

ABSTRACT

We provide two empirical models for calculating the sailing time and berth time of maritime container liner networks to effectively model the ambiguity associated with sea and port contingency for ex-ante decisions of fleet deployment and route planning. The models are based on recorded AIS data of 110 mega vessels including all the operating container mega vessels with a capacity of 16,000 TEU or more during the summer of 2015. The models are able to estimate the sailing time (with R² of 0.974) and the berth time (with R² of 0.895) without knowledge of any operational-level explanatory variables. The models are validated against the published East Asia–North Europe services. Moreover, the study reveals that vessel operators adopt different berthing and sailing strategies even under the same conditions.     

Numerical simulation of interference effects for a high-speed catamaran

The simulations of the flow around a high-speed vessel in both catamaran and monohull configurations are carried out by the numerical solution of the Reynold averaged Navier–Stokes (RANS) equations. The goal of the analysis is the investigation of the interference phenomena between the two hulls, with focus on its dependence on the Reynolds number (Re). To this aim, numerical simulations are carried out for values of Re ranging from 10⁶ to 10⁸ for two different values of the Froude number (Fr = 0.30, 0.45). Wave patterns, wave profiles, limiting streamlines, surface pressure and velocity fields are analyzed; comparison is made between the catamaran and the monohull configurations. Dependence of the pressure and viscous resistance coefficients, as well as of the interference factor, on the Reynolds number is investigated. Verification and validation for both resistance coefficients and wave cuts is also performed.     

A product life cycle approach to urban waterfronts: The revitalization of Galveston

Abstract

Urban waterfronts are increasingly the focus of revitalization efforts designed to enhance tourism and recreation. The evolution of urban waterfronts suggests that these resources experience distinct stages of introduction, growth, maturity, decline, and sometimes revitalization. In this paper the product life cycle is broadened to describe the evolution of the waterfront district of Galveston, Texas. Implications of the product life cycle model of urban waterfront revitalization pertain to public policy formation, “product”; development, and management response to different life cycle stages.     

Lessons Learned from Lake Shiwha Project

The Lake Shiwha Project was planned in the late of 1980s about 10 years before establishing ICZM policy and wetland conservation policy in Korea. The project was to build a dike of 12.7 kilometers in the mouth of a estuary, thereby to keep freshwater instead of brackish in the lake and to create land of 110 square kilometers for agriculture and industrial complex by draining out of associated wetland. However the Korean government abandoned keeping freshwater in the lake as soon as completing the dike because of not being able to control of serious pollution in the lake. This article analyzes the characteristics of the project such as bias of feasibility, degree of transformation and time period of loss of goal that led into environment disaster and extracts some implications for lessons.     

Evaluating seaport policy alternatives: a simulation study of terminal leasing policy and system performance

The competitive characteristics of the North American seaport industry have, in theory, been causally linked to excess investment and low terminal throughput productivity. This paper empirically examines the link between seaport authority container terminal leasing policy and throughput productivity. Recent advances in inventory theory applied to service industries suggest the pooling of demand uncertainty can yield lower costs without sacrificing customer service. This concept is applied to a container seaport using simulation. The effort compares key output measures from a realistic base case model of the seaport to those generated by an alternative terminal leasing policy. It is shown that the pooling of demand in a common-user seaport reduces total vessel time in port by 17.1% with no reduction in TEU throughput. Throughput productivity is improved for the highest capacity terminals, while lower capacity terminals are made available for additional users or alternative uses.     

Implementation Challenges for Quota Set-Asides: Policy Analysis to Inform Fisheries Management Decision-Making

Abstract

The implementation of catch share programs can have socio-economic and ecological benefits, yet may also change the distribution of those benefits within a fishery or across communities. Quota set-asides can mitigate the impacts of these changes. During the implementation of the West Coast groundfish trawl catch share program, 10% of the quota was set aside to be used toward five goals in the Adaptive Management Program (AMP). This quota was to serve as an insurance policy during the substantial changes that were expected to occur under the new management regime. However, this program has not yet been fully developed, in part due to delayed decision-making and the controversial nature of allocating quota. Here, we examine and score six policy options for the AMP against four criteria: effectiveness, flexibility, political viability, and implementability. While each of the options has strengths and weaknesses, those that ranked highly include allocating quota pounds (QP) via the status quo and via auction. Our results highlight the drawbacks of delaying contentious decisions, where uncertainty for participants can constrain operational decisions and subsequent economic gains. We demonstrate the utility of this decision-making framework for evaluating tradeoffs between alternatives, especially for a program with multiple, competing objectives.     

Container terminal employees’ perceptions of the effects of sustainable supply chain management on sustainability performance

ABSTRACT

Sustainability has become an important issue in container terminal operations. However, relatively little research has been conducted to assess its association with sustainable supply chain management (SSCM). In this study, SSCM consists of internal sustainability practices and external sustainability collaboration. We empirically examined the effects of internal sustainability practices and external sustainability collaboration on sustainability performance in container terminal operations at the Port of Kaohsiung in Taiwan. We developed a model adopting the SSCM construct, which consisted of two dimensions: internal sustainability practices and external sustainability collaboration. Several research hypotheses were formulated from the theory and the hypotheses were tested using survey data collected from 141 employees who worked with container terminals. We found that internal sustainability practices and external sustainability collaboration positively affected sustainability performance, whereas external sustainability collaboration had a positive influence on internal sustainability practices. There is a discussion of the implications of these findings for developing sustainability and improving sustainability performance in container terminals and ports.     

Israel's coastal program: Resource protection through management of land use

Abstract

Presently, much of Israel's 190‐kilometer‐long Mediterranean coast is either unoccupied, devoted to unsuitable uses, or is in use by activities which have no special need to be near the water's edge. This has resulted from years of lack of appreciation by policy‐makers of the coast as a valuable resource, of national development policies that directed attention to other regions, and of the relatively limited demand for coastal recreation.

In the last decade the importance of these factors has diminished. In turn, there is now mounting pressure for the development of coastal land. Increasingly, rising standards of living with a greater demand for recreational facilities, the growth of tourism as a major industry, and demands of the environmental lobby for conservation of part of the coastal land are factors bound to cause intensive change along the coast and to affect the quality of its resources. These trends have brought about public intervention in deciding the future of the coast. This paper reviews and analyzes Israel's coastal policy and its resource management programs, and also discusses the potential challenges to their full implementation.

Three types of programs were suggested as the main management tools: a coastal research and development effort, national coastal land use planning and pollution prevention, and monitoring and control programs. Major objectives of the programs were to be achieved through land use controls. Consequently, an important role is given in the development and implementation of the coastal program to agencies responsible for the management of physical land use planning and development.

Successful implementation of the management program, however, will depend on the ability of its administrators to coordinate the actions of many interests, on success in changing attitudes among decision‐makers as to the value of the coast, and on widening support for coastal resource conservation among a presently uninvolved public.     

The Importance of Brokers in Collaborative Marine Ecosystem-Based Management of Social Ecological Systems

Abstract

Practitioners play a critical yet largely unexamined role in translating collaborative, ecosystem-based management (EBM) for social-ecological systems from theory to practice. We paired mental models and social network analytical methods and applied them to two cases of marine EBM in Rhode Island and New York, focusing on practitioners themselves, to understand the relationship between practitioners’ mental models of marine ecosystems and the extent and nature of collaboration within each network. Mental models analysis was used to assess the comprehensiveness and balance of practitioners’ mental models, and social network analysis was used to assess the role and influence of practitioners within each network. A comparative statistical analysis was then performed to understand the relationship between mental models and network measures. Research revealed a statistically significant correlation between practitioners’ mental model comprehensiveness and practitioners’ influence within the network. In other words, practitioners with comprehensive mental models of the ecosystem for which they were planning were found to act as “brokers,” connecting those who were not otherwise connected, bridging jurisdictions, sectors, and disciplines. Results underscore the importance of brokers in achieving the collaborative and integrated goals of EBM and suggest the need for greater attention to practitioners’ role in EBM implementation.     

Simulation optimization of the berth allocation in a container terminal with flexible vessel priority management

ABSTRACT

Solving the berth allocation problem (BAP) in ports is not trivial where the berth resources are limited and various sizes of vessels arrive with dramatically dissimilar loads. Especially in real scenarios, arriving vessels are accepted for a berth with the first come first served (FCFS) priority rule. This study proposes a decision support system coupled with a simulation optimization module based on the swarm-based Artificial Bee Colony optimization algorithm for solving the BAP. The proposed methodology was implemented for the Izmir port in Turkey. To investigate the influences of the vessel priorities on the BAP, four different experimental scenarios based on the single (SQM) and multiple queue models (MQM) were coupled with FCFS and proposed hybrid queue priority (HQP) rule. The results indicated that SQM scenarios were superior to MQM scenarios in a manner of minimizing the average vessel waiting times and the implementation of a dynamic berth allocation strategy for the MQM significantly decreases the vessel waiting times. Results of the SQM also imply that utilization of the HQP approach further minimizes the average vessel waiting times and increases the berth utilization and port throughput without yielding excessive waiting times for the larger vessels compared with the FCFS priority rule.     

Some economic aspects of conflicts over land use in the coastal zone

Abstract

Recent land use legislation pays particular attention to the coastal zone where age‐old conflicts have recently accelerated. Flexibility is required in policy because visible conflicts are tied into complex physical and social systems which may require changing patterns of land use over time. Public policy is altering property rights and a thorough understanding of the economic and social roles played by those rights is required. Economic models can be used to understand some major changes such as types of alteration of the environment, but may be ignored or misused unless a better understanding of coastal decision processes is developed.     

Examining Residents’ Proximity,Recreational Use,and Perceptions Regarding Proposed Aquaculture Development

Competing interests related to marine resources have the potential to create conflict in the coastal zone. In many parts of the world marine farms exist in close proximity to areas that support recreation and tourism. The purpose of this study was to examine residents’ perceptions of proposed marine farm development related to their proximity to, and recreational use of, a coastal area in New Zealand. Residents from two areas were surveyed about their recreational use of the region and about perceptions related to marine farm development. Results indicated that those living closest to proposed marine farms used the area more often and in different ways, were most sensitive to marine farm development, and were less positive in their evaluations of marine farms, despite agreeing that marine farms can have positive economic consequences for nearby communities. Implications for using stakeholder input for the planning and management of marine farms are discussed.     

Ecological and economic principles in park planning: The Assateague national seashore model

Abstract

The National Park Service is required by law to conserve nationally significant resources for public benefit. Susceptibility to local short‐term economic pressures and a lack of understanding of resource dynamics can jeopardize mandate compliance. Assateague National Seashore is an example of a dynamic barrier island where early understanding of ecologic factors should have preceded its establishment and must precede its management and development. Research conducted on a similar system has demonstrated the dramatic environmental impacts and high maintenance costs associated with an inappropriate recreation management scheme. Alternatives are available which minimize resource degradation and maintenance costs without restricting visitation. To better ensure incorporation of long‐run ecologic and economic criteria into the decision‐making process, a proposal is put forward which recognizes the need for an expanded research effort and close adherence to early planning steps.     

Ecological conversion efficiency and its influencers in twelve species of fish in the Yellow Sea Ecosystem

The ecological conversion efficiencies in twelve species of fish in the Yellow Sea Ecosystem, i.e., anchovy (Engraulis japonicus), rednose anchovy (Thrissa kammalensis), chub mackerel (Scomber japonicus), halfbeak (Hyporhamphus sajori), gizzard shad (Konosirus punctatus), sand lance (Ammodytes personatus), red seabream (Pagrus major), black porgy (Acanthopagrus schlegeli), black rockfish (Sebastes schlegeli), finespot goby (Chaeturichthys stigmatias), tiger puffer (Takifugu rubripes), and fat greenling (Hexagrammos otakii), were estimated through experiments conducted either in situ or in a laboratory. The ecological conversion efficiencies were significantly different among these species. As indicated, the food conversion efficiencies and the energy conversion efficiencies varied from 12.9% to 42.1% and from 12.7% to 43.0%, respectively. Water temperature and ration level are the main factors influencing the ecological conversion efficiencies of marine fish. The higher conversion efficiency of a given species in a natural ecosystem is acquired only under the moderate environment conditions. A negative relationship between ecological conversion efficiency and trophic level among ten species was observed. Such a relationship indicates that the ecological efficiency in the upper trophic levels would increase after fishing down marine food web in the Yellow Sea ecosystem.     

Neural network-based fuel consumption estimation for container ships in Korea

ABSTRACT

Due to the outstanding strength of advanced machine-learning techniques, they have become increasingly common in predictive studies in recent years, particularly in predicting ship energy performance. In constructing predictive models, prior studies have mostly employed vessels’ technical parameters to establish machine-learning algorithms. To bridge this research gap and enable wider applications, this paper presents the design of a multilayer perceptron artificial neural network (MLP ANN) as a machine-learning technique to estimate ship fuel consumption. We utilized the real operational data from 100–143 container ships to estimate fuel consumption for five different container ships grouped by size. We compared the performance of two ANN models and two multiple-regression models. Four input parameters (sailing time, speed, cargo weight, and capacity) were included in the first ANN and the first regression model, while the other two models only consider two inputs from physical function. The mean absolute percentage error of the ANN models with four inputs was the smallest and less than those in extended statistical models, demonstrating the MLP’s superiority over the statistical model. The MLP ANN model can thus be applied to confirm the effectiveness of the slow-steaming method for achieving energy efficiency.