Improvement of the Usability of Online Mentoring Website

The purpose of this study is to improve the usability of the current online mentoring website by deriving what should be improved through assessment and reflecting it to system improvement. The related data such as search log and Think Aloud were collected from user groups (9 users in total), and usability was tested according to the predefined test procedures. The collected data were analyzed, using quantitative methods. In terms of search log, the related items including effectiveness, efficiency, satisfaction and error were quantified according to usability testing standards. Then, descriptive statistics was performed. According to usability comparison before and after system improvement, it has mostly improved such as improved effectiveness (increase by 15 points), better efficiency (reduction by 41 seconds), increase in satisfaction (by 8 points) and decrease in error frequency (decrease by 1.2 times). Usability testing should be viewed as a process, not outcome itself. Therefore, it could be used during system prototype in addition to the current system and useful in system improvement

Electric field control of nonvolatile four-state magnetization at room temperature

We find the realization of large converse magnetoelectric (ME) effects at room temperature in a multiferroic hexaferrite Ba$_{0.52}$Sr$_{2.48}$Co$_{2}$Fe$_{24}$O$_{41}$ single crystal, in which rapid change of electric polarization in low magnetic fields (about 5 mT) is coined to a large ME susceptibility of 3200 ps/m. The modulation of magnetization then reaches up to 0.62 $\mu$$_{B}$/f.u. in an electric field of 1.14 MV/m. We find further that four ME states induced by different ME poling exhibit unique, nonvolatile magnetization versus electric field curves, which can be approximately described by an effective free energy with a distinct set of ME coefficients

Structure stability evaluation of offshore heave compensator using multi-body dynamics analysis method

Heave compensator attenuate vessel heave motion during drilling operation of drillship. Heave compensator functions as damping form motion of drillship, such as principle spring of suspension system. The load transfers on the parts of heave compensator. Stress and deformation of all parts is evaluated to diagnose the stability of the compensator. This study makes a decision on the safety of structure. Results of analysis confirm the structure stability of heave compensator for simulation. This result can be used as data for structural analysis to determine safety of a structure

Quality of Service Control for WLAN-based Converged Personal Network Service

This paper proposes a framework for quality of service (QoS) control in WLAN-based converged personal network service (CPNS). First, we show that the CPNS devices in WLANs occupy the shared wireless channel in an unfair manner; and thus, QoS is degraded. The reasons of such problem are analyzed from two viewpoints of (i) channel access mechanism according to carrier sensing multiple access protocol of WLAN and (ii) TCP congestion control mechanism in response to packet loss. To improve QoS and assure fair channel sharing, we propose an integrated QoS control framework consisting of admission control and rate control. Based on the available capacity, the admission control determines whether or not a specific QoS service can be admitted. The rate control is implemented using congestion window control or token bucket algorithm. The proposed mechanism differentiates QoS service from best-effort (BE) service such that the QoS service is preferentially served to satisfy its QoS requirements and the BE service is served to share the remaining resource in a fair manner. The extensive simulation results confirm that the proposed scheme assures QoS and fair channel sharing for WLAN-based CPNS

Familial Glucocorticoid Deficiency with a Point Mutation in the ACTH Receptor: A Case Report

Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disorder characterized by severe glucocorticoid deficiency associated with failure of adrenal responsiveness to ACTH but no mineralocorticoid deficiency. We report a 2 month-old boy of nonconsanguineous parents, presented with hyperpigmentation. Physical examination showed diffuse dark skin of body including, oral mucosa, gum, hands, nails and scrotum. Laboratory evaluation revealed low serum cortisol (0.3 µg/dL), with very high plasma ACTH level (18,000 pg/mL), and serum cortisol level did not increase after ACTH stimulation test. Serum sodium, potassium, plasma renin activity, aldosterone and 17-hydroxyprogesterone were normal. Sequence analysis of the ACTH receptor (MC2R) gene showed a homozygous mutation of D103N. Diagnosis of FGD was made and treatment started with oral hydrocortisone

A WPAN Platform Design in Mobile Phone Considering Application Development and Usability

In this paper, we propose a WPAN (Wireless Personal Area Network) platform for converged network services integrating a cellular network and a WPAN. We mainly focus on an easy-to-develop and easy-to-use WPAN platform for wireless communication services using both networks. The proposed WPAN platform consists of a WPAN handset platform, a WPAN connection scheme, and a WPAN server platform. The WPAN handset platform provides abstract WPAN API (Application Programming Interface) set and application management module. Using the WPAN connection scheme, the user can enjoy converged network services in a convenient way. The WPAN server platform manages the overall services and digital devices that are connected to the handset. Compared to the existing WPAN related platform, we consider the need for the integrated service components allowing for the development of WPAN applications in the handset and their convenience for the user. Also, illustrative services and devices are implemented using the proposed method, which show the applicability of the proposed WPAN platform

Long-term clinical course of a patient with mucopolysaccharidosis type IIIB

Mucopolysaccharidosis type III (MPS III) is a rare genetic disorder caused by lysosomal storage of heparan sulfate. MPS IIIB results from a deficiency in the enzyme alpha-N-acetyl-D-glucosaminidase (NAGLU). Affected patients begin showing behavioral changes, progressive profound mental retardation, and severe disability from the age of 2 to 6 years. We report a patient with MPS IIIB with a long-term follow-up duration. He showed normal development until 3 years. Subsequently, he presented behavioral changes, sleep disturbance, and progressive motor dysfunction. He had been hospitalized owing to recurrent pneumonia and epilepsy with severe cognitive dysfunction. The patient had compound heterozygous c.1444C>T (p.R482W) and c.1675G>T (p.D559Y) variants of NAGLU. Considering that individuals with MPS IIIB have less prominent facial features and skeletal changes, evaluation of long-term clinical course is important for diagnosis. Although no effective therapies for MPS IIIB have been developed yet, early and accurate diagnosis can provide important information for family planning in families at risk of the disorder

Characteristics of Body Fat, Body Fat Percentage and Other Body Composition for Koreans from KNHANES IV

Accurate measurement of fat mass has become increasingly important with the increasing incidence of obesity. We assessed fat and muscle mass of Koreans with the Korea National Health and Nutrition Examination Survey IV (KNHANES IV). We studied 10,456 subjects (aged 20 to 85 yr; 4,476 men, 5,980 women). Fat and muscle mass were measured by dual-energy x-ray absorptiometry. Reference values of body compositions were obtained using the LMS method. The fat mass index (FMI, body fat mass/height2; kg/m2) of Korean men did not correlate with age (P = 0.452), but those of Korean women (P < 0.001) did. The ratio of percentage of fat in the trunk and legs was positively related with age in both the genders. The appendicular lean mass/height2 (kg/m2) of Korean men was negatively related to age (P < 0.001). In women, this ratio increased with age (P < 0.001). When we defined obesity according to the FMI classification, the rates of obesity were 6.1% (FMI > 9 kg/m2) in men and 2.7% (FMI > 13 kg/m2) in women. It is concluded that the muscle mass decreases and obesity increases with aging in Korean men, whereas both fat mass and obesity increase with aging in Korean women

Two Different Renal Cell Carcinomas and Multiple Angiomyolipomas in a Patient with Tuberous Sclerosis

We report a case of tuberous sclerosis associated with two histologically different renal cell carcinomas (RCCs) and multiple angiomyolipomas (AMLs) in the same kidney. A 43-year-old female was admitted to our hospital with left flank pain and a huge palpable mass in the left flank area. Abdominal computed tomography revealed two concurrent RCCs and multiple AMLs in the left kidney. Because of the clinical suspicion of RCC, the patient underwent left radical nephrectomy. On gross examination, the total size of the resected left kidney was 30.5×17×8 cm. Microscopically, the upper pole tumor features were consistent with chromophobe RCC and the midpole tumor was a clear-cell RCC. The multifocal masses in the remaining remnant parenchyma were AMLs. Six months after surgery, the patient is healthy without signs of tumor recurrence