2,666 research outputs found
The study of consumption patterns and expectations of organic catering consumers in Taiwan
This report was presented at the UK Organic Research 2002 Conference. Organic catering is increasingly provided in public and private food services. In Taiwan, most organic catering is vegetarian and affiliated with organic food stores. These offer diners organic meals to make themselves competitive to attract target markets, and provide related information to improve consumers’ knowledge of organic foods and hopefully increase their consumption. Organic catering consumers’ knowledge of organic foods, attitudes toward consumption, and consumption behavior are all related. Consumption is affected by gender, marital status, age, religion, education, occupation, personal health, family health and expenditure allowance. Regular organic catering customers emphasize “balanced nutrition” and “certification or reliability of organic sources”. The obstacles to consumption for non-regular organic catering consumers are “too expensive” and “difficult to find”. Most organic catering consumers prefer the service styles “health-themed restaurant” and “located inside the organic food stores”
Recommender Systems with Characterized Social Regularization
Social recommendation, which utilizes social relations to enhance recommender
systems, has been gaining increasing attention recently with the rapid
development of online social network. Existing social recommendation methods
are based on the fact that users preference or decision is influenced by their
social friends' behaviors. However, they assume that the influences of social
relation are always the same, which violates the fact that users are likely to
share preference on diverse products with different friends. In this paper, we
present a novel CSR (short for Characterized Social Regularization) model by
designing a universal regularization term for modeling variable social
influence. Our proposed model can be applied to both explicit and implicit
iteration. Extensive experiments on a real-world dataset demonstrate that CSR
significantly outperforms state-of-the-art social recommendation methods.Comment: to appear in CIKM 201
Heuristic Algorithm to Minimize Total Weighted Tardiness on the Unrelated Parallel Machine with Sequence Dependent Setup and Future Ready Time
This study presents a heuristic algorithm to minimize total weighted tardiness on unrelated parallel machines with sequence-dependent setup time and future ready time. We propose a new rule based on Apparent Tardiness Cost (ATC). The performance of the rule is evaluated on unrelated parallel machines. In order to solve a problem, we use a look-ahead method and a job-swap method. When a machine becomes idle, the heuristic compares the jobs on the machine and selects the one with the smallest total tardiness value to carry out a process.
The propose heuristic is divided into three stages: The first stage employs the newly introduced dispatching rule, ATC with continuous setup and ready time for unrelated parallel machines (ATCSR_UP), along with a look-ahead heuristic to select the initial job for each machine. The second stage, consisting of several iterations, schedules the rest of the job on the machine. Each iteration starts by finding the job with the smallest tardiness. The ATCSR_Rm rule proposed by Lin and Hsieh (2013) concerns the unrelated-parallel-machine scheduling which this study examines, so we compare our ATC-based rule with their proposed rule. Although they study a separable setup time in their research, no other paper than Lin and Hsieh (2003) focus on unrelated parallel machine with future ready times. In their WSPT term, they consider the processing time for each job; our own rule considers processing time, setup time, job ready time, and machine time. We consider the setup time, job ready time, and machine time because — according to the continuous sequence-dependent setup rule — setup time should be included in processing time (Yue and Jang 2013). In addition, job ready time and machine time should also be included in the processing time. Adding setup time 〖(s〗_(i,j)), job ready time (r_j), and machine time (t_m) to the formula thus makes the formula more accurate.
Lin and Hsieh (2013) use max(r_j,t_i+s_(i,j) ) for the slack term, and they compare the ready time with the sum of the machine available time 〖(t〗_i) and the setup time 〖(s〗_(i,j)). However, in our formula, we consider ready time, machine time, and current time. Current time (t) is used when a job might come at a future time when the machine in question is idle or has finished the job.
The last term of the propose heuristic is the ready term, which uses both ready time (r_j) and machine time (t_m), because it needs to specify whether ready time (r_j) or machine time (t_m) goes first. If a job is ready to be processed but the machine is not ready, the job has to wait. We use ready time (r_j) and machine time (t_m) because this makes the formula more suitable for practical, real-world us
Comparisons of GM (1,1), and BPNN for predicting hourly particulate matter in Dali area of Taichung City, Taiwan
AbstractThis paper represents the first study to compare seven types of first–order and one–variable grey differential equation model [abbreviated as GM (1, 1)] and back-propagation artificial neural network (BPNN) for predicting hourly particulate matter (PM) including PMio and PM2.5 concentrations in Dali area of Taichung City, Taiwan. Their prediction performance was also compared. The results indicated that the minimum mean absolute percentage error (MAPE), mean squared error (MSE), and root mean squared error (RMSE) was 16.76%, 132.95, and 11.53, respectively for PM10 prediction. For PM2.5 prediction, the minimum MAPE, MSE, and RMSE value of 21.64%, 40.41, and 6.36, respectively could be achieved. All statistical values revealed that the predicting performance of GM (1, 1, x(0)), GM (1, 1, a), and GM (1, 1, b) outperformed other GM (1, 1) models. According to the results, it revealed that GM (1, 1) could predict the hourly PM variation precisely even comparing with BPNN
Maternal Demographic and Psychosocial Factors Associated with Low Birth Weight in Eastern Taiwan
The relationship between birth weight and maternal sociodemographic characteristics was examined in a sample from two teaching hospitals in eastern Taiwan. Using a structured questionnaire, we conducted face- to-face interviews with women at antenatal clinics between 1998 and 1999 in Hualien City. One year later, we took the outcome of pregnancy from medical records and birth certificates from the Public Health Bureau of Hualien County. Of the 1,128 single live births, 6.8% had low birth weight (LBW) using the World Health Organization cut-off of 2,500 g. LBW was more common in teenage (< 20 years), older (> 30 years), first-time, and unmarried mothers; those with basic/intermediate educational attainment; and residents of aboriginal districts. Teenage pregnancies were more likely than those in adults to be unplanned, and such mothers had smoking or alcohol-drinking behavior. Prevention of teenage pregnancy is crucial to lower LBW rates in eastern Taiwan. For adult mothers, basic or intermediate educational attainment, residence in an aboriginal district, and first-term pregnancy were significant factors associated with LBW, after adjustment for other psychosocial attributes, such as psychologic distress and poor family support. Thus, we should pay more attention when caring for pregnant women with such sociodemographic characteristics, and ensure that they have adequate prenatal care and can adopt a healthy lifestyle
Measuring Topological Field Theories: Lattice Models and Field-Theoretic Description
Recent years have witnessed a surge of interest in performing measurements
within topological phases of matter, e.g., symmetry-protected topological (SPT)
phases and topological orders. Notably, measurements of certain SPT states have
been known to be related to Kramers-Wannier duality and Jordan-Wigner
transformations, giving rise to long-range entangled states and invertible
phases, such as the Kitaev chain. Moreover, measurements of topologically
ordered states correspond to charge condensations. In this work, we present a
field-theoretic framework for describing measurements within topological field
theories. We employ various lattice models as examples to illustrate the
outcomes of measuring local symmetry operators within topological phases,
demonstrating their agreement with the predictions from field-theoretic
descriptions. We demonstrate that these measurements can lead to SPT,
spontaneous symmetry-breaking, and topologically ordered phases. Specifically,
when there is emergent symmetry after measurement, the remaining symmetry and
emergent symmetry will have a mixed anomaly, which leads to long-ranged
entanglement.Comment: 43 page
Comfort-Centered Design of a Lightweight and Backdrivable Knee Exoskeleton
This paper presents design principles for comfort-centered wearable robots
and their application in a lightweight and backdrivable knee exoskeleton. The
mitigation of discomfort is treated as mechanical design and control issues and
three solutions are proposed in this paper: 1) a new wearable structure
optimizes the strap attachment configuration and suit layout to ameliorate
excessive shear forces of conventional wearable structure design; 2) rolling
knee joint and double-hinge mechanisms reduce the misalignment in the sagittal
and frontal plane, without increasing the mechanical complexity and inertia,
respectively; 3) a low impedance mechanical transmission reduces the reflected
inertia and damping of the actuator to human, thus the exoskeleton is
highly-backdrivable. Kinematic simulations demonstrate that misalignment
between the robot joint and knee joint can be reduced by 74% at maximum knee
flexion. In experiments, the exoskeleton in the unpowered mode exhibits 1.03 Nm
root mean square (RMS) low resistive torque. The torque control experiments
demonstrate 0.31 Nm RMS torque tracking error in three human subjects.Comment: 8 pages, 16figures, Journa
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