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The aim of this study was to investigate the effect and timing of recombinant human parathyroid hormone analog (PTH) administration for preventing medication-related osteonecrosis of the jaws (MRONJ) using a murine model. After standardized MRONJ induction using zoledronic acid and dexamethasone injections, 48 female Sprague-Dawley rats were divided into four groups according to the timing of PTH administration before or after dental extraction. Rats were euthanized 3 weeks after dental extraction, followed by clinical and histologic analyses. No clinical improvements were observed in the preoperative and postoperative PTH groups, compared to controls (p = 0.638 and 0.496, respectively). However, on histological analysis, the number of empty lacunae reduced significantly, and the number of blood vessels increased in the preoperative PTH group (p = 0.004 and 0.002, respectively). The postoperative PTH group did not show significant differences for empty lacunae and blood vessels compared to controls (p = 0.075 and 0.194, respectively). The reduction in the empty lacunae and the increase in the blood vessels in the preoperative PTH group were significant compared to other groups, suggesting more viable bone tissue in this group. In perspective, preoperative PTH use may represent a better prophylactic regimen for preventing the occurrence of MRONJ after traumatic dental or surgical procedures, especially in patients with a history of long-term bisphosphonate administration or at high risk of developing MRONJ. However, the findings should be proven in further studies on other animals followed by clinical trials.

A prominent mandibular angle produces a characteristic quadrangle with a coarse appearance. Asians prefer getting the shape of their jaws surgically corrected into a V-line, which is assumed to give a more intelligent, beautiful, and delicate appearance. According to many studies, mandibular contouring surgery may jeopardize mechanical stability. The aim of this study was to analyse the stress on the mandible during function after mandibular contouring surgery using finite element analysis. Based on computed tomography scans, the three-dimensional models of preoperative mandible, mandibular angle ostectomy, and sagittal cortical ostectomy of the mandibular ramus and body with angle ostectomy were obtained. Boundary conditions to restrict movement on both condyles and clenching tasks (incisal clench, right molar clench, and right group clench) were simulated. The sagittal cortical ostectomy model had the highest strain energy (48.51 J) and von Mises stress (77.39 MPa) during the right molar clench task. The maximum von Mises stress on the sagittal cortical ostectomy was increased by up to approximately four times compared with the cases of preoperative mandible. The stress was concentrated at the site of operation, mandibular condyle, and angle. In the case of the sagittal cortical ostectomy model, bone resorption may occur, and there is a possibility of fracture during the right molar clench task. These results suggest that mandibular contouring surgery may be related to the fragility of the mandible, since surgery significantly alters its biomechanics. The degree of surgery may be a determining factor in the stress and fracture risk of the mandible. Therefore, clinicians should establish an accurate and correct treatment plan for the safe prognosis of patients after surgery.

BACKGROUND Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation (NIBS) technique designed to improve cognitive and physical function of stroke survivors. There are many studies being conducted in the search for an effective intervention of tDCS. This study focused on cognitive motor learning in relation to hand function of stroke survivors. MATERIAL AND METHODS We enrolled 30 subjects with cognitive and hand function disorders. The participants in each group were inpatients at a hospital in Korea and had undergone neurorehabilitation training (60 min). Groups 1 and 3 had tDCS applied for 20 min, while group 2 received sham tDCS for the same duration. Afterwards, groups 1 and 2 played Nintendo games for 20 min, but group 3 did not. The total intervention period was 40 min/day, 2 days/week, for 8 weeks. The cognitive and hand function of the subjects were assessed using the Trail Making Test (TMT-A, TMT-B), Grip strength, Box and Block Test (BBT), and the Manual Function Test (MFT) before and after intervention. RESULTS The tDCS + Nintendo Switch game group showed significant differences in TMT-A, TMT-B, Grip strength, MFT, and BBT results compared to the other groups between before and after intervention (p

Storage systems in general and databases in particular usually balance between write durability and performance. It is not uncommon that write durability often relies on transaction systems that also offer a relaxed model of durability for performance. As hardware vendors provision more cores and faster storage devices, attaining fast data durability for concurrent file writes is demanding to high-performance storage systems in large-scale cluster systems. We approach the challenge by proposing a system that uses a small amount of fast persistent memory for buffering concurrent file writes while preserving data durability. The main technical issue in designing a durable file buffer is allowing concurrent file writes to store data in a shared and limited space of persistent memory without incurring lock or resource contention. This article addresses such issue and presents AutoBahn, a durable file buffer that expedites file I/O operations. To prove practicality and effectiveness, we implemented a prototype of AutoBahn in Linux-4.8.7 and ran several key-value systems—Redis, RocksDB, and WiredTiger—on AutoBahn. Evaluation results on a multicore server demonstrate that all the key-value systems achieved performance levels almost matching the non-durable counterpart. AutoBahn is a useful method that can efficiently deal with concurrent file I/O streams on multicores and fast storage devices.

The impact of health risk behaviours on the social and economic fabric of society is of concern to social marketers and policy makers. Current research suggests social capital, that is, the positive benefits gained from a relationship with others in the community, plays a key role in addressing health risk behaviours. The current literature on social capital and health is fragmented, and the field has yet to produce an up-to-date synthesis of past findings to help researchers understand the current status of this research area. This article fills this gap with an integrative review of empirical research based on rigorous criteria. Boolean search was used to limit the search to only those articles containing the keywords ‘social capital’ and ‘health risk’ but no limits were applied for country or population of interest or publication start date. Two researchers screened through the title, abstract and introduction of every retrieved article independently according to the inclusion criteria. A total of 105 articles were eligible for further analyses. This article contributes by: (1) providing a structured overview with an aim to disentangle the findings of varied past studies addressing the theme; (2) identifying important gaps in current knowledge; (3) presenting a research agenda that flows logically from the theoretical gaps identified; and lastly (4) proposing a theoretical framework upon which social capital interventions can be designed and executed to mitigate health risk. We hope that the key issues and new directions presented in this paper will provide new impetus in this area of research.

Atomic force microscopy (AFM) is used to induce electrostatically charged areas on nitrogen-ion-implanted ultrananocrystalline diamond (UNCD) films by applying a bias voltage to the AFM tip during the tapping mode scan. For local and intentional electrostatic charging, both positive and negative charges can be stored on pristine as well as nitrogen-ion-implanted UNCD films, as detected by Kelvin probe force microscopy. Interestingly, the charge storage capacity of pristine UNCD increases with the N-ion implantation dose. The potential amplitude and spatial distribution of the trapped charges can be controlled by the bias and load applied to the tip. The enhanced charge storage properties with doping are attributed to the formation of impurities, various defects, and the induction of an enhanced graphitic sp2 phase because of the high N-ion implantation dose, where all act as trapping centres for extra charge. The formation of various defect states and conducting sp2 nanographitic phases facilitate enhanced charge storage in N-ion-implanted UNCD films. This study underscores the potential importance of doping-dependent charge storage and the role of defects and nanographitic phases as a strategy for enhancing the electrostatic charge storage capability of diamond-based charge storage devices.

Cisplatin, a representative anticancer drug used to treat cancer, has many adverse effects. In particular, it causes significant damage to the kidneys. Thus, many researchers have studied the delivery of drugs, such as cisplatin, to cancer areas using targeted drug-delivery systems. Here, we propose a new way to treat cancer by delivering anticancer drugs directly to the tumor site using the electrospray (ES) technique. We determined the optimal conditions for ES to promote the introduction of cisplatin into cancer cells. In our results, the group with cisplatin delivery-based electrospray (CDES) at 6 kV had an apoptosis of cancer cells approximately two times more than the group treated with cisplatin alone. We also confirmed that ES alone did not affect the survival of cells up to a voltage of 6 kV, but increased the permeability of the cell plasma membrane instantaneously, facilitating the influx of the drug.

While potteries are common artifacts excavated in archaeological sites, the restoration process relies on manual cleaning and reassembly of shattered pieces. Since the number of possible 3D configurations is considerably large, the exhaustive manual trial may result in abrasion on fractured surfaces and even failure to find the correct matches. As a result, many recent works suggest virtual reassembly from 3D scans of the fragments. The problem is challenging in the view of the conventional 3D geometric analysis, as it is hard to extract reliable shape features from the thin break lines. We propose to optimize for the global configuration by combining geometric constraints with information from noisy shape features. Specifically, we enforce bijection and continuity of sequence of correspondences given estimates of corners and pair-wise matching scores between multiple break lines. We demonstrate that our pipeline greatly increases the accuracy of correspondences, resulting in stable restoration of 3D configurations from irregular and noisy evidence.

For the past four decades, database checkpointing has long been a major system activity triggering heavy I/O and leading to performance fluctuations. This is unpleasing to database systems pursuing good and steady performance on high-end computing platforms. Hence, commercial and open-source databases usually spawn massive page flushers to complete the required tasks with system disruptions being minimized. In this work, to reduce the hefty cost, we propose Demeter, designs for hardware-assisted database checkpointing that unbundles checkpointing by offloading the task of building new pages from physical changes onto storage devices equipped with near-data processing (NDP) capability. Demeter consists of two parts; a software component designed for generating physical updates without affecting foreground transactions and a hardware part constructing new pages from the changes. For evaluation, we have built a prototype system based on the Biscuit framework and integrated Demeter with MariaDB. Experimental results demonstrated that the Demeter-enabled engine substantially reduces the amount of I/O and its foreground transaction processing gains more throughput than the vanilla system under the OLTP workloads modifying a large volume of data pages.

This research investigates how temporal distance influences leisure travellers’ assessment of hotel attributes, and further examines whether gender moderates the impact of temporal distance...

Combinatorial allogeneic NK cell therapy with Pembrolizumab for cholangiocarcinoma; interim report of open label Phase1/2a study Background: There are several things needed to be resolved for successful efficacy when NK cell therapy is applied for solid tumor; improvement of NK cell invasion into tumor, activation and production of a large number of NK cells, etc. Basically, in human, NK cell number is relatively small compared to other immune cells such as T cell and the number becomes severely low when NK cell is obtained from cancer patients. For these reasons, allogeneic NK cell has been used for clinical studies against various cancer types. Recently, we also have finished a phase1 study of allogeneic NK cell therapy for cholangiocarcinoma, enrolling 9 patients at inoperable and no chemotherapy favorable stage due to side effects. Four of nine patients (44%) showed SD (stable disease) after six NK cell injections and no severe AE (adverse event) was found. In this following phase 2a study, to bring out immuno-synergetic effect of NK cell therapy against the inoperably advanced bile duct cancer, we have designed a combinatorial protocol with using Pembrolizumab. Methods: Enrollment of 40 bile duct cancer patients has been finished for a combinatorial study of allogeneic NK cell therapy with Pembrolizumab at two different sites in Korea (ClinicalTrials gov, NCT03937895). Patients were eligible for the enrollment when they were inoperable and no chemotherapy favorable stage due to side effects, and also when they had PD-L1-positive score. For treatment, the most favorable method for highly activated allogeneic NK cell production has been determined from our previous study, resulting that 3x106 NK cells per kg are injected for each dose along with Pembrolizumab injection. Pembrolizumab (200mg) was given every 3 weeks for up to 9 times and NK cell injection was given for up to 18 times during the maximum injection period of Pembrolizumab. Results: Six patients (pts) were first enrolled for the pilot combinatorial study, dosing 6 times of NK cells and 3 times of Pembrolizumab. The result showed no severe AE from the injections. Among the five pts finished the injections, 2 pts showed SD (Stable Disease) and continued the treatment, being enrolled into the Phase 2a in which 34 more pts were enrolled. Among the 20 pts finished 6 NK cell and 3 Pembrolizumab injections (1st RECIST), 65% of pts showed SD. When 12 NK cell and 6 Pembrolizumab injections finished (2nd RECIST), pts had 40% and 20% of SD and PR (Partial remission). Of the 3 pts at 3rd RECIST (18 NK cell and 9 Pembrolizumab), 1 and 2 pts showed SD and PR, respectively. Finding pts experienced AE, a total of 6 AEs has been reported: no treatment-related AE, one grade 3 (Encephalopathy), and five grade 1-2 with common AE. In a recent safety and efficacy study of pembrolizumab alone (10mg/kg, every 2 weeks for up to 2 years) with 28 pts of advanced bile duct cancer showing PD-L1 expression, 17% pts showed PR, 17% pts and 52% had SD and PD (progressive disease), respectively. Although our study is still ongoing, continuing the combinatorial treatment gives rise to PR, suggesting that NK cell therapy with Pembrolizumab shows an immuno-synergetic effect for the cancer. Biomarker experiments with the injected NK cells supports our finding and we will discuss this at presentation. Citation Format: Yong Yoon Chung, Seung Woo Park, Jung-Min Im, Da-Kyung Yoo, Hyo-Cheon Cheon, Jae-Eun Kim, Kyeong-Pill Lim, Eun-Hee Yang, Hye-Jin choi, Hyo-Sun Chung, Seo-Yeon Kim, Ju-Yong Lee, In-Hye Jung, Seung Min Bang, Moon Jae Chung, Sung Ill Jang, Jae Hee Cho, Hee Seung Lee, Jung Youp Park, Jung Hyun Jo. Combinatorial allogeneic NK cell therapy with Pembrolizumab for cholangiocarcinoma; interim report of open label Phase1/2a study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT171.

BACKGROUND Handgrip strength and walking speed predict and influence cognitive function. We aimed to investigate an exercise protocol for improving handgrip strength and walking speed, applied to patients with chronic stroke who had cognitive function disorder. MATERIAL AND METHODS Twenty-nine patients with cognitive function disorder participated in this study, and were randomly divided into one of two groups: exercise group (n=14) and control group (n=15). Both groups underwent conventional physical therapy for 60 minutes per day. Additionally, the exercise group followed an exercise protocol for handgrip using the hand exerciser, power web exerciser, Digi-Flex (15 minutes); and treadmill-based weight loading training on their less-affected leg (15 minutes) using a sandbag for 30 minutes, three times per day, for six weeks. Outcomes, including cognitive function and gait ability, were measured before and after the training. RESULTS The Korean version of Montreal Cognitive Assessment (K-MoCA), Stroop test (both simple and interference), Trail Making-B, Timed Up and Go, and 10-Meter Walk tests (p

Because of its high passivation quality, Al2O3 is used as the front passivation layer in commercial n-type silicon solar cells. The front passivation layer of a solar cell should have passivation properties and antireflection properties. For process efficiency and protection, SiNx is used as a capping layer on Al2O3. However, the Al2O3/SiNx stack layer has an issue with firing stability during screen printing of the cell, similar to the Al2O3 layer. This is because the Al2O3/SiNx stack layer needs to be fired to form the metal contact. In this study, the firing stability of the Al2O3/SiNx stack layer is investigated and the relation between blister formation and passivation is elucidated. Annealing improves the passivation quality of layers after firing. The order of annealing and stack formation is also one of parameters for firing stability. We used thermal atomic layer deposition to form Al2O3 and plasma enhanced chemical vapor deposition to form SiNx. The refractive index of each layer is 1.6 and 2.0, respectively, and the thickness is 10 nm and 70 nm, respectively. Rapid thermal processing was used for the annealing and firing. Passivation qualities were determined by quasi steady-state photo conductance, and blistering was observed by optical microscopy. Although there is some blistering on the sample annealed at 600 °C, good passivation and good firing stability was observed. We identified that a low density of blisters formed during the annealing step improves the firing stability of the passivation layer by preventing abrupt blister formation during the firing step, which is the cause of thermal degradation.

This study sought to investigate the effects of obesity on falls and dynamic stability control in young adults when subject to a standardized treadmill-induced gait-slip. Forty-four young adults (21 normal-weight and 23 obese) participated in this study. After their muscle strength was assessed at the right knee under maximum voluntary isometric (flexion and extension) contractions, participants were moved to an ActiveStep treadmill. Following 5 normal walking trials on the treadmill, all participants encountered an identical and unexpected slip defined as a perturbation in the anterior direction with the magnitude of 24-cm slip distance and 2.4-m/s peak slip velocity. The trials were categorized as a fall or recovery based on the reliance of the subject on external support following the slip. Compared with the normal-weight group, the obese group demonstrated less relative muscle strength and fell more responding to the slip (78.3% vs. 40.0%, p=0.009). After adjusting the body height and gender, the results indicated that the obese group was 19.1-time (95% confidence interval: [2.06, 177.36]) more prone to a fall than the normal-weight group when experiencing the same treadmill-induced slip. The obese group showed significantly impaired dynamic stability after slip possibly due to the inability of controlling the trunk segment׳s backward lean movement. Obesity measurements explained more slip outcome variance than did the strength measurements (53.4% vs. 18.1%). This study indicates that obesity most likely influences the ability to recover from slip perturbations. It is important to develop interventions to improve the capability of balance recovery among individuals with obesity.

This research advances the theory and practice of luxury brand advertising effectiveness by decoding brand–consumer engagement grounded in narrative transportation. An online semi-structured qualitative questionnaire incorporates a modified thematic apperception testing projective technique and is administered in three target countries for luxury brands: France, Korea and Australia. Respondents were exposed at random to global ads from one of four brands: Hermes, Chanel, Louis Vuitton and Gucci. Narratives produced are analyzed with thematic and text analysis. The research contributes to luxury brand advertising research by identifying a route to persuasion based on the level of implicit narrative transportation engendered by the brand's advertising. While respondents express cultural differences in the way they script their experiences, an implicit route to engagement is equally effective across cultures.

압전 진동 에너지 수확 장치(PEH: piezoelectric vibration energy harvester)의 에너지 변환 효율에 관Key Words: Vibration(진동), Energy Harvesting(에너지 수확), Piezoelectricity(압전), Conversion Efficiency(변환효율), Impedance Matching(임피던스 정합), Electro-Mechanical Coupling Coefficient(전기-역학 연성 계수) 초록: 압전 진동 에너지 수확 장치의 설계 및 성능 평가 시 에너지 변환 효율을 고려하는 것은 매우 당연하다. 본 연구에서 고려하는 에너지 변환 효율은 부하 저항이 부착된 압전 진동 에너지 수확 장치에 입력되는 가진 진동 파워 대비 전기 출력 값으로 정의된다. 기존의 연구에서는 근사적으로 임피던스 정합된 부하 저항에서의 전기 출력을 고려한 반면, 본 연구에서는 최적의 임피던스 정합 값을 사용하여 새롭게 에너지 변환 효율 식을 유도하였다. 유도된 식의 타당성을 검증하기 위해 3개의 서로 다른 전기-역학 연성 계수 값을 갖는 진동 에너지 수확 장치에 대한 유한 요소 해석 결과를 이용하였다. 또한, 부하 저항의 임피던스 정합 방법의 차이에 따른 에너지 변환 및 변환 효율 특성을 살펴보았다. Abstract: To properly design and assess a piezoelectric vibration energy harvester, it is necessary to consider the application of an efficiency measure of energy conversion. The energy conversion efficiency is defined in this work as the ratio of the electrical output power to the mechanical input power for a piezoelectric vibration energy harvester with an impedance-matched load resistor. While previous research works employed the electrical output power for approximate impedance-matched load resistance, this work derives an efficiency measure considering optimally matched resistance. The modified efficiency measure is validated by comparing it with finite element analysis results for piezoelectric vibration energy harvesters with three different values of the electro-mechanical coupling coefficient. New findings on the characteristics of energy conversion and conversion efficiency are also provided for the two different impedance matching methods.

This work proposes a more practical way of designing the piezoelectric energy harvesting skin, which facilitates the application of the proposed idea to any practical engineering facilities with vibration. Unlike earlier studies to make use of analytical model for piezoelectric energy harvesting design, this work proposes an experimental method to design a piezoelectric energy harvesting skin using operating deflection shapes of a target mechanical system. This method is more practical in the sense that actual vibration of a target mechanical system can be characterized far better for the piezoelectric energy harvesting design. The key idea is to extract continuous in-plane normal strain values from discrete out-of-plane deformations of a target mechanical system. From multiple strain inflection lines, piezoelectric energy harvesting skin segments are designed to maximize a total power output. It is demonstrated that four piezoelectric energy harvesting skin segments designed by the proposed idea can generate sufficient power from the outdoor condensing unit of an air conditioning for self-powered operation of a wireless sensor network.

Accurate predictions of the amount of harvestable energy available from ambient vibrations are important for design of energy harvesters and for their integration in specific applications. This need has motivated the development of many mathematical models for piezoelectric energy harvesters (PEHs). Existing models, however, require material and geometric PEH data that are often incorrect and/or unavailable. As a more accurate and practical means to meet this need, we propose an energy conversion model of a cantilevered PEH that requires only geometric data and modal parameters that can be directly measured using a standard vibration test. The newly proposed model facilitates calculation of the maximum output power and thus enables visualization of the harvestable energy from the target vibrating structure. Prediction accuracy of the proposed model was confirmed in our study through finite element analysis and experimental results. Practical use of the proposed energy conversion model was demonstrated by applying it to a cooling fan unit of a boiler facility in a power plant.

DC electrical outputs of a piezoelectric vibration energy harvester by nonlinear rectifying circuitry can hardly be obtained either by any mathematical models developed so far or by finite element analysis. To address the issue, this work used an equivalent electrical circuit model and newly developed an algorithm to efficiently identify relevant circuit parameters of arbitrarily-shaped cantilevered piezoelectric energy harvesters. The developed algorithm was then realized as a dedicated software module by adopting ANSYS finite element analysis software for the parameters identification and the Tcl/Tk programming language for a graphical user interface and linkage with ANSYS. For verifications, various AC electrical outputs by the developed software were compared with those by traditional finite element analysis. DC electrical outputs through rectifying circuitry were also examined for varying values of the smoothing capacitance and load resistance.

Effectively promoting products and services is important for the success of tourism companies in the competitive business environment. Based on construal level theory, this study examines whether psychological distance (temporal and spatial) influences preferred promotional messages in the tourism industry. The results from three experimental studies indicate that people who plan a vacation in the distant-future/to a far-destination prefer abstract promotional messages, while those who plan in the near-future/to a near-destination prefer concrete ones. We also find that informational media (textual vs. pictorial) have significant influences regarding the impact of psychological distance on travelers’ preferred promotional information. Further, using a field study, we investigate whether the current advertisements produced by tourism organizations are properly designed to be congruent with spatially driven construal levels (e.g., concrete promotional information for a near destination) but find them incongruent with what this study suggests. Implications of the findings are discussed for both researchers and practitioners.

Purpose – The purpose of this paper is to investigate what values luxury customers may seek to fulfill during their interaction with salespersons and how perceived value fulfillment may impact salesperson loyalty and store loyalty. The paper also examines the moderating effect of the degree of friendship with a salesperson. Design/methodology/approach – The authors conducted a survey using a close-ended questionnaire. In total, 22 luxury fashion brand stores located in eight of the largest department stores in Seoul, Korea, were selected as the luxury fashion retail context for the research. A total of 220 questionnaires were used for data analysis. Findings – Fulfillment of self-oriented values had a significant positive influence on store loyalty and fulfillment of stimulation had a significant positive influence on salesperson loyalty. There was significant interaction effect between stimulation and degree of friendship on salesperson loyalty. Research limitations/implications – The results of this study provide practical implications in the management of customer relationship. An emphasis on qualities of luxury products that are linked to the fulfillment of self-oriented and/or personal values such as superior quality or ability to gain emotional benefits should be warranted for success as a luxury brand or a luxury retailer. Originality/value – This research is important as it can inform luxury salesperson on how to better meet customer's psychological needs in the context of a selling situation; ultimately contribute to their salesperson loyalty and loyalty to the brand.

Appearance management includes “all activities and thought processes leading to the purchase and wear of clothing items as well as processes of body modification” (e.g., piercings, tattooing) (Kaiser, 1997, p. 5). We focused on investigating the processes of appearance socialization by uncovering the types of appearance management rules learned from or attributed to significant others as well as rules learned from other members of the socio-cultural environment experienced during childhood and adolescence. Within appearance management our focus was on rules related to body supplements (e.g., clothing, accessories) as well as rules concerning body modifications (e.g., tattoos, piercings). Our research questions were as follows: 1) What were the appearance management rules learned during childhood and adolescence? 2) From whom or what did these rules come from and how were individuals taught these rules? 3) What types of conflicts were experienced over rules of appearance management and how were these conflicts resolved? Data was collected from young adults ( n = 43). Participants were asked to recall a specific time period during their childhood and adolescent years and to write about their experiences concerning what appearance “rules” they learned, how they learned them, and from whom. They were also asked to share any conflicts they experienced and how these conflicts were resolved. Many of the recollected rules centered on aesthetic concerns and contextual aspects of appearance management. Mothers were key socializing agents and at the center of conflicts over appearance. The most common resolution styles were compliance and problem solving.

전극 발생 전하량의 허수부 Key Words: Vibration Energy Harvesting(진동 에너지 수확), Piezoelectric(압전), Diagonal Segment(대각선 분할), Mode Sequence Change(모드 순서 변경) 초록: 본 연구에서 제안한 압전 진동 에너지 수확 장치는 기존 외팔보의 직사각형 면이 대각선을 따라 분할되어 2개의 에너지 수확 단위로 구성되어 있다. 부 구조물은 주 구조물이 진동 에너지 원에 부착되는 방향과 반대 방향으로 주 구조물의 끝단에 부착되어 있으며, 각 에너지 수확 단위는 폐회로 상태의 고유 진동수가 일치하도록 설계되었다. 동일한 고유 진동수를 갖는 2개의 구조물이 연결될 때 관찰되는 일반적인 현상과 달리, 제안된 구조에서는 고유 진동수 분리가 작으며, 1차 및 2차 모드의 순서가 바뀌어 나타난다. 이로 인해 출력 전력 역시 특정 주파수 근처에서 집중 생성된다. 상용 유한 요소 해석 소프트웨어를 사용하여 제안된 진동 에너지 수확 장치의 최대 생성 전력이 동일한 설치 영역 및 끝단 질량을 갖는 기존 외팔보 형태의 장치에 비해 실질적으로 향상됨을 보였다. Abstract: This study proposes a piezoelectric vibration energy harvester composed of two diagonally segmented energy harvesting units. An auxiliary structural unit is attached to the tip of a host structural unit cantilevered to a vibrating base, where the two components have beam axes in opposite directions from each other and matched short-circuit resonant frequencies. Contrary to the usual observations in two resonant frequency-matched structures, the proposed structure shows little eigenfrequency separation and yields a mode sequence change between the first two modes. These lead to maximum power generation around a specific frequency. By using commercial finite element software, it is shown that the magnitude of the output power from the proposed vibration energy harvester can be substantially improved in comparison with those from conventional cantilevered energy harvesters with the same footprint area and magnitude of a tip mass.

A cantilevered piezoelectric energy harvester(PEH) and an auxiliary mass-spring unit can be integrated into a novel two-degrees-of-freedom PEH where its lowest eigenmode is not an in-phase modes but an out-of-phase mode. This typical behavior was shown to enhance output power considerably compared with its stand-alone counterpart. The objective of this study is to newly develop a continuum-based mathematical model suitable for efficient analysis of the mode-sequence reversed PEH. Once such a mathematical model is available, various physical behaviors can be analytically investigated for better designs. After a new mathematical model is developed, its validity is checked by using ANSYS results, in terms of resonant frequency, open-circuit voltage, and output power with a specified external resistance.

There are widespread tidal flats along the southwestern coast of Korea. At the provincial level, Jeonnam region has the largest tidal flat area, of which the main part is located in Shinan-gun, a municipality consisting of only islands. This area, including its tidal flats, has a high species diversity as well as a high cultural. However, the various important ecological functions of tidal flats are not recognized, as in most cases the tidal flats are utilized simply as reclaimed land. During the period of Japanese colonialism in the 20th century large-scale reclamation of tidal flats took place in Shinan-gun, and rice was produced on the land that was reclaimed. From the standpoint of ecological services, tidal flats can be more than agricultural fields. Even though tidal flats have not yet been analyzed from the cultural perspective so much, their value can be expected to be very high. As an aggregation of a variety of ecological functions that occur by ecological processes, tidal flats have the better value in terms of ecological services than other land uses. This new, richer understanding of the value of tidal flats should be a stimulus to maximize its value by thoughtful landscape management and planning.

PurposeThe purpose of this paper is to present a comprehensive review of the body of literature concerning human factors in retail environments and their influence on consumers. Additionally, the authors identify the research gaps in the literature and suggest directions for future research.Design/methodology/approachThis study uses qualitative approaches to provide a comprehensive review of human factors in retail environments.FindingsThe review is synthesised based on two main categories: the effects of other customers and the effects of sales associates. The influence of other customers, including the number of customers and social relations, is a significant source of human‐related environmental cues. In addition, existing studies support the importance of the number of sales associates, sales associates' physical attributes, and their behavioural characteristics observed in stores.Practical implicationsThis study suggests that retailers need to effectively manage, control and manipulate human‐related environmental factors in order to generate a positive influence on consumers' perceptions towards stores and their behaviours.Originality/valueThis study provides a conceptual framework that integrates various human‐related factors in retail environments and their significant insights in the effective management of these factors identified for researchers and retailers.

For most applications of the vibration energy harvesting technology as in wireless sensor networks for smart buildings and plants, the evaluation of DC output performance of vibration energy harvesters is typically required. However, there is no dedicated algorithm for the evaluation. The lack of a dedicated algorithm results from difficulties in the direct incorporation of nonlinear rectifying and regulating circuitry into finite element models of piezoelectric vibration energy harvesters. In this study, we develop a dedicated algorithm and present software based on it for the evaluation of not only AC but also DC electrical quantities. Here, an equivalent electrical circuit model is employed. The COMSOL multiphysics simulation tool is adopted for extracting equivalent electrical circuit parameters of a piezoelectric vibration energy harvester and MATLAB is used to make a graphical user interface. The AC voltage and power outputs calculated by the proposed algorithm under various conditions are compared with those by a traditional finite element analysis. The DC output voltage and power through a rectifier are obtained for varying values of smoothing capacitance and external resistance.

In four experiments, participants made a purchase decision about a counterfeit product under either constrained or unconstrained cognitive resource conditions. Participants were less likely to purchase the counterfeit when their cognitive resources were constrained than when they were not. However, this difference was evident only when individuals had strong (vs. weak) moral beliefs, or when they had low (vs. high) accountability for their decisions. These and other results suggest that the effect of cognitive resource availability on counterfeit purchase was mediated by participants’ perceptions of justification about the purchase.

The rapid urbanization in developing countries is accelerating both the depletion and fragmentation of urban green space, despite the known positive effects of green spaces on the environmental conditions in cities and the quality of life of residents. Consequently, there is a need for practical tools that can support the development of networks of urban green spaces. This article presents a study that used a GIS-based least cost path (LCP) analysis to identify the best alternative for developing an urban green space network in the coastal city of Jakarta, Indonesia, which was based on the evaluation of topography and land use characteristics. Pair-wise analysis was used to reduce the sensitivity in the LCP model. The results showed that the coastal wetlands in the northern part of Jakarta and the agricultural fields in the suburban areas of Jakarta play an important role in connecting the green space network. On the other hand, some green spaces in the central part of Jakarta could not be connected by the LCP model. The method used in this study can serve as a tool to support the identification of networks of potential urban green spaces. It can also provide useful information for sustain able urban landscape planning and management in urban ecosystems. However, the inclusion of socio-economic criteria would further improve the model.

The objective of this work is to find an optimal actuator arm configuration in hard disk drives (HDD's) for sufficiently small arm bending-induced off-track error by maximizing the fundamental eigenfrequency of arm bending modes subject to a constraint on the mass moment of inertia of arms. By applying the topology optimization method for the purpose, an arm configuration having two balancing holes instead of a single balancing hole in conventional designs was obtained. It is numerically shown that an optimized arm configuration substantially increases the arm bending resonant frequency with little change in the mass moment of inertia of arms in comparison with conventional designs having a single balancing hole. Finally, the performance of an optimized actuator arm is verified by showing that the eigenfrequencies associated with arm bending modes are increased by about 100 Hz and the off-track error by measuring the position error signal (PES) from actual sample drives can be reduced by as much as 25%.

This research was focused on investigating why some consumers might support cause-related marketing campaigns for reasons other than personal benefit by examining the influence of moral emotions and cultural orientation. The authors investigated the extent to which moral emotions operate differently across a cultural variable (US versus Korea) and an individual difference variable (self-construal). A survey method was utilised. Data were collected from a convenience sample of US (n = 180) and Korean (n = 191) undergraduates. Moral emotions significantly influenced purchase intention for a social-cause product. The influence of an ego-focused moral emotion (i.e., pride) on purchase intention was greater for US than Korean participants. The influence of another-focused moral emotion (i.e., guilt) on purchase intention was greater for high-interdependent participants than for low-interdependent participants. The findings of this research provide important and relevant implications to marketers and policy makers in developing persuasive messages and customer relationship programmes.

This work presents the application of the DFSS (Design for Six Sigma) methodology to optimizing both the linearity and the sensitivity of the output voltage of a Hall-effect rotary position sensor. To this end, the dimensions and relative positions of a permanent magnet with reference to a Hall sensor are selected as the design factors for a full factorial design. In order to evaluate the output voltage of the rotary position sensor at each run in the experimental design, analytical solutions to the magnetic flux density were obtained using the Biot-Savart law and the relations between the magnetic flux density and the output voltage intrinsic to a Hall sensor. Through measurements of the improved output voltage of the rotary position sensors manufactured using the optimized design factors, the proposed method is shown to be simple and practical.

This investigation presents a finite element method to obtain the transmission properties of bulk elastic waves in piezoelectric band gap structures(phonon crystals) for varying frequencies and modes. To this end, periodic boundary conditions are imposed on a three-dimensional model while both in-plane and out-of-plane modes are included. In particular, the mode decoupling characteristics between in-plane and out-of-plane modes are identified for each electric poling direction and the results are incorporated in the finite element modeling. Through numerical simulations, the proposed modeling method was found to be a useful, effective one for analyzing the wave characteristics of various types of piezoelectric phononic band gap structures.

Land-use changes due to the socio-economic environment influence landscape patterns and processes, which affect habitats and biodiversity. This study considers the effects of such land-use changes, particularly on the traditional rural “Maeul” forested landscape, by analyzing landscape structure and vegetation changes. Three study areas were examined that have seen their populations decrease and age over the last few decades. Five types of plant life-forms (Raunkier life-forms) were distinguished to investigate ecosystem function. Principle component analysis was used to understand vegetation dynamics and community characteristics based on a vegetation similarity index. Ordination analysis transformed species-coverage data was introduced to clarify vegetation dynamics. Landscape indices, such as area metrics, edge metrics, and shape metrics, showed that spatial heterogeneity has increased over time in all areas. Pinus densiflora was the main land-use plant type in all study areas but decreased over time, whereas Quercus spp. increased. Over a decade, P. densiflora communities shifted to deciduous oak and plantation. These findings indicate that the impact of human activities on the Maeul landscape is twofold. While forestry activities caused heavy disturbances, the abandonment of traditional human activities has led to natural succession. Furthermore, it can be concluded that the type and intensity of these human impacts on landscape heterogeneity relate differently to vegetation succession. This reflects the cause and consequence of patch dynamics. We discuss an approach for sustainable landscape planning and management of the Maeul landscape based on traditional management.

Percutaneous endoscopic lumbar discectomy (PELD) can be performed under local anesthesia with intravenous analgesics. To define the incidence of piriformis syndrome (PS) after PELD via the posterolateral approach under local anesthesia compared to that of general patients presenting with low back pain with/without lower leg pain. The incidence and time of occurrence of positive FAIR test after PELD within a 3-month follow-up period were evaluated retrospectively, and compared with the prevalence of general patients who visited the pain clinic for LBP with/without lower leg pain. Factors that may increase the incidence of PS after PELD were also evaluated. There was no patient with positive FAIR test immediately after PELD in the operation room and before walking. The prevalence of PS in general patients was 317/2,320 (13.7%); however, the incidence of PS after PELD within a 3-month follow-up period was 61/151 (40.4%), peaking at 32 days. High anxiety scale scores during operation led to increased incidence of PS after PELD. PELD under local anesthesia with high level of anxiety may increase the incidence of PS after walking, peaking around the first month, compared with the results for general patients with low back pain with/without lower leg pain.

Unlike single-physics static structural problems, the topology optimization of piezoelectric systems involves three different material coefficient groups, such as the mechanical, electrical, and electromechanical coefficient groups, which correspondingly necessitate three values of penalty exponents. Earlier investigations have shown that stable convergence cannot be ensured if the exponents are selected arbitrarily or based simply on typical rules used for static structural problems. Here, stable convergence implies that the use of more materials can yield better system performance and a distinct void–solid distribution is favored over an intermediate material distribution during the optimization process. However, no rule for choosing the values of penalty exponents has yet been studied for piezoelectric systems and in fact, they have been chosen mainly by trial and error. In this work, two conditions that the three penalty exponents must satisfy for stable convergence are derived for one-dimensional problems and their effectiveness for two-dimensional problems is investigated. The first condition is an intrinsic condition ensuring better energy conversion efficiency between mechanical and electric energy for more piezoelectric material usage and the second one is an objective-dependent condition favoring a distinct void–solid distribution over an intermediate material distribution for the same amount of piezoelectric material used. In this study, we consider the design of piezoelectric actuators, sensors and energy harvesters that can be analyzed by static analysis. Several numerical examples are solved to check the validity of the proposed conditions.

In recent years, there has been a stronger demand for the weight reduction of components of various portable electronic devices. This work is motivated by the need to reduce the weight of a camera shutter module without much decreasing the torque generated by its magnetic circuit. Because the camera shutter speed is most significantly affected by the torque, the magnitude of the generated torque should also be considered in the design for the weight reduction. Thus, we formulate the design problem as a torque maximization problem under various mass constraints. Specifically, we propose to formulate it as a topology optimization problem of magnetic circuits and find optimal shapes of yokes (and magnets) in the circuits. For the maximization formulation, the objective function is chosen as the average of clockwise and counterclockwise torques over a whole range of rotation angles of a magnet corresponding to the shutter opening angle. Limits on the mass of the yoke and magnet in a magnetic circuit are imposed as constraints. The torque generated by a magnetic circuit is calculated by the modified Maxwell stress tensor method. A series of mass constraint ratios is considered to investigate the effects of the mass usage on the magnitude of torque generated by optimized circuits. The region occupied by the yoke (and the magnet) is designated as a design domain, while coils are assumed to belong to a non-design domain. By demonstrating that the optimized magnetic circuits outperform a nominal circuit, the use of the average torque as an objective function including a corresponding treatment of a rotating magnet proposed in this work is shown to be effective for the topology optimization of magnetic circuits in a camera shutter module.

Among the diverse strategies that businesses use to maximize sales, the customer-salesperson relationship as an aspect of relationship marketing has been reported as one of the most critical (O’Malley and Tynan, 1998). Although relationship marketing has been emphasized across various business settings, this strategy works particularly well in luxury markets for a number of reasons. For example, brands offering high involvement products (i.e., luxury brand products) focus on relationship marketing rather than those offering low involvement products (Martin, 1998). Previous researchers have recognized the role of various customers attributes in sales interactions (Walker et al., 1977; Weitz, 1981). One customer attribute that may play a role in moderating the association between the strength of customer-salesperson relationship and sales effectiveness is a customer’s tendency to self-monitor (Snyder, 1974). This is due to the fact that an individuals’ self monitoring tendency has been recognized a...

Background Xenotransplantation using fresh porcine corneas has been suggested as a feasible alternative to overcome the shortage of human donor corneas. Successful long-term survival of grafts without evidence of xenozoonosis in clinically applicable pig-to-non-human primate corneal transplantation model has brought researchers close to human clinical trials. Accordingly, we aimed to prepare a clinical trial protocol to conduct the first corneal xenotransplantation. Methods We developed the clinical trial protocol based on international consensus statement on conditions for undertaking clinical trials of corneal xenotransplantation developed by the International Xenotransplantation Society. Detailed contents of the protocol have been modified with reference to comments provided by ophthalmologists and multidisciplinary experts, including an infectionist, an organ transplantation specialist, a clinical pharmacologist, a neuropsychiatrist, a laboratory medicine doctor, and a microbiologist. Results Two patients with bilateral legal corneal blindness (best-corrected visual acuity ≤20/200 in the better eye and ≤20/1000 in the candidate eye) or with (impending) corneal perforation will be enrolled. During the screening period, participants and their family members will have two separate deep consideration periods before signing informed consent forms. Each patient will undergo corneal xenotransplantation using fresh corneas from Seoul National University miniature pigs. Commercially available immunosuppressants will be administered and systemic infection prophylaxis will be performed according to the program schedule. After transplantation, each patient will be monitored at a specialized clinic to investigate safety up to 2 years and efficacy up to 1 year. Conclusions A detailed clinical trial protocol for the first corneal xenotransplantation reflecting the global guidelines is provided.