• Title/Summary/Keyword: fixed point method

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Implementation and Economic Evaluation of Movable Power Supply Device for Electric Vehicle (EV용 이동형 전원공급장치의 구현 및 경제성 평가에 관한 연구)

  • Choi, Sung-Moon;Han, Byeong-Gill;Lee, Hu-Dong;Kim, Mi-Young;Rho, Dae-Seok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.77-86
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    • 2020
  • Power quality problems caused by feeder voltage drop and extension construction cost problems can occur with the increasing utilization rates of the existing fixed-type EV (electric vehicle) charger. Moreover, EV users might not be able to access the EV charger due to a lack of EV charging facilities. Therefore, this paper proposes an MPSD (movable power supply device) for EVs to overcome user inconvenience caused by the insufficient number of chargers and extension cost issues. The proposed MPSD was mainly composed of a PV (photovoltaic) system, ESS (energy storage system), EV charging system, and monitoring and control system. Furthermore, there are three operation modes available to enhance the flexibility of the MPSD application, depending on the situation. This paper also presents an economical evaluation modeling using the present worth method to consider the cost and benefit elements. The simulation results based on proposed modeling showed that MPSD is more economical than the existing EV charger. Moreover, its profit can be increased significantly depending on the distance to the installation point.

A Study on the Electrical Characteristics of Ge2Sb2Te5/Ti/W-Ge8Sb2Te11 Structure for Multi-Level Phase Change Memory (다중준위 상변환 메모리를 위한 Ge2Sb2Te5/Ti/W-Ge8Sb2Te11 구조의 전기적 특성 연구)

  • Oh, Woo-Young;Lee, Hyun-Yong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.35 no.1
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    • pp.44-49
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    • 2022
  • In this paper, we investigated current (I)- and voltage (V)-sweeping properties in a double-stack structure, Ge2Sb2Te5/Ti/W-doped Ge8Sb2Te11, a candidate medium for applications to multilevel phase-change memory. 200-nm-thick and W-doped Ge2Sb2Te5 and W-doped Ge8Sb2Te11 films were deposited on p-type Si(100) substrate using magnetron sputtering system, and the sheet resistance was measured using 4 point-probe method. The sheet resistance of amorphous-phase W-doped Ge8Sb2Te11 film was about 1 order larger than that of Ge2Sb2Te5 film. The I- and V-sweeping properties were measured using sourcemeter, pulse generator, and digital multimeter. The speed of amorphous-to-multilevel crystallization was evaluated from a graph of resistance vs. pulse duration (t) at a fixed applied voltage (12 V). All the double-stack cells exhibited a two-step phase change process with the multilevel memory states of high-middle-low resistance (HR-MR-LR). In particular, the stable MR state is required to guarantee the reliability of the multilevel phase-change memory. For the Ge2Sb2Te5 (150 nm)/Ti (20 nm)/W-Ge8Sb2Te11 (50 nm), the phase transformations of HR→MR and MR→LR were observed at t<30ns and t<65ns, respectively. We believe that a high speed and stable multilevel phase-change memory can be optimized by the double-stack structure of proper Ge-Sb-Te films separated by a barrier metal (Ti).

A Study for Encouragement of Rublic System in Designing with Programming Classes (설계과목 프로그래밍 수업을 중심으로 루브릭 시스템 정착을 위한 연구)

  • Jo, Mi-Kyung;Park, Hyun-Seok
    • Journal of the Korea Society of Computer and Information
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    • v.14 no.11
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    • pp.81-90
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    • 2009
  • It is inevitable for college students to be confused when they first face university education, which requires them to be self-reliant and responsible, after finishing their course of education, which is passive under control of period and environment, in primary, middle, and high schools. Introduction to college courses, which require students to be subjective and responsible, to be taken after chronically and environmentally controlled primary and secondary education, are but confusing. In this stage, college education should provide ground for educational system so that students can escape from repetitively enforced way of studying of fixed curriculums and study creatively and subjectively while befitting each individual's aptitude. For instance, in programming classes in engineering school, students scholastic achievements are closely interrelated with the professor's educational principles. A change in method of education, from one previously focused on theoretical contents to one centered on practices and experiments, can reap good results. Also, as the need arose for introduction of practice-focused evaluation system, from recognition-centered professor evaluating system to enablement of actively developing creative and self-reliant way of learning, we applied the Rublic System. It is a feedback system that all or most students become the evaluators, of which the indicators of evaluation such as category, standard, and score are public. We have looked into whether or not there has been an improvement in GPAs of students, and if there exists an improvement then what efforts should be made to solidify the system.

Exploring Meaning for Change of Social Awareness of Art Activity (예술활동의 사회적 인식변화를 위한 의미 탐색)

  • Seo, Sang-Gyu;Oh, Kwang-Suk;Sin, Dae-Sik;Hong, Sea-Hee;Sung, Gun-Jae;Jung, Ha-Ni
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.5
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    • pp.167-173
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    • 2019
  • This study aimed to point out the social meaning of acting and art and the change of perception according to the time change. The research method was based on qualitative research through literature review. Based on the findings of this study, the following conclusions should be made. Acting is an art directly linked to the life of an individual. Therefore, the life of an individual is an activity that sublimates his or her life into art through acting. Every activity that we do in our daily life is acting, which is directly related to our talents. In other words, a talented person is recognized as a good actor, and a person with a lack of talent plays the role of an extra person. However, talent is influenced by effort and is also influenced by a given environment. That is, an individual's talent is not fixed but can be changed according to the situation. Education is the area that deals with the possibility of changing these talents. Education has been operating in a variety of ways, but with regard to acting, it has long been centered on apprenticeship education. However, as the 20th century began, systems gradually began to emerge, and in recent years, countries have developed into different educational systems. Therefore, it is necessary to practice the development and operation of various education programs so that the acting and the art are naturally applied in everyday education process and can be applied in daily life.

Structural Performance Evaluation of Anchors for Power Equipment Electrical Cabinets Considering On-Site Installation Conditions (현장 설치 조건을 고려한 발전설비 전기 캐비닛 정착부 앵커의 구조성능 평가)

  • Lee, Sang-Moon;Jung, Woo-Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.43 no.6
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    • pp.709-719
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    • 2023
  • In general, most of the electrical equipment responsible for control within power plants is housed in self-standing cabinets. These cabinets are typically fixed to a slab using post-installed anchors. Although the fixation method of using post-installed anchors provides stability, there is a risk of conductor failure due to external forces, including moments. However, the performance assessment of current anchors is only evaluated through uniaxial material tests. Therefore, the primary purpose of this study is to compare the static performance of post-installed anchors, considering on-site installation conditions, with their performance in material tests and to analyze the behavioral characteristics of the anchors. While conducting experiments using actual cabinets would be ideal, practical and spatial constraints make this approach difficult. As an alternative, experiments were conducted using a test specimen consisting of a steel column and a support. As a result, the pull-out performance of anchors reflecting on-site installation conditions was measured to be about 10% higher than that observed in material tests. The trends in load reduction and the point of maximum performance for the anchors also differed. To verify the reliability of the experimental study, a 3D FEM analysis was performed, which will provide predictive information on the loads transferred to the post-installed anchors for structural performance evaluations of electrical cabinets using shaking table test in the future.

A STUDY OF THE NORMAL & ABNORMAL OCCULSAL PATERNS IN ADULTS USING THE SUPERIMPOSED RUBBER PATTERN METHOD (Superimposed Rubber Pattern법에 의한 성인 정상 및 비정상 교합자의 교합 양상에 관한 연구)

  • Choi, Dae-Gyun;Lee, Sung-Bok;Kwon, Young-Hyuk;Choi, Boo-Byung
    • The Journal of Korean Academy of Prosthodontics
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    • v.33 no.3
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    • pp.467-491
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    • 1995
  • In order to analyze the occlusin of intercuspation with maximun bite force, fifteen healthy adult subjects with the ages 23 to 27 were studied(Group1 ; 5-normal occlusion with Angle's Class1, Group2 ; 5-Angle's Class2 malocclusion, Group3 ; 5-Angle’s Class3 malocclusion). Head Position was fixed with occlusal plane paralleling to horizontal line and occlusal registration r cord was made with polyether rubber impression material(Ramitec, ESPECo. West Germany). After all subject were trained for maximum intercuspation at least 5 times, occlusal registration procedure was repeated for this study. Lower posterior rubber occlusal registration records were sliced with 1mm thickness using precision metal sliding channel(Hitachi Ind. Co., Japan). Gross sectional drawings were traced from occluding view of upper and lower posterior teeth on the rubber slices using digitizer, and superimposed for the determination of each drawing distance(Superimposed Rubber Pattern Method). Based on superimposed rubber pattern drawings, total area of occlusal view, sum of each area of the 5 divided occlusal contact provinces and its ratio, total area and number of occlusal contact area were determined to elucidate occlusal stability in the normal and abnormal occlusion groups. The data were analysed by t-test(p=0.05) to determine statistical significance. The obtained results were as follows : 1. Group1 showed the largest standard area with occlusal view of the lower posterior teeth and Group3 showed the smallest area. There was a significant difference between Group2 and Group3(p=0.025), and Gropu1 was not statistically different for both Group2 and Group3. 2. Means and ratio of the under 2.0mm area(D) and ratio showed $197.49mm^2$, 59.76% in Group1, $188,69mm^2$, 56.10% in Group2, and $174.23mm^2$, 55.76% in Group3. The results that Group1 has the most area/ratio and Group3 has the least area/ratio can be considered Group1 is the most advantageous for masticatory effective area, and Group3 is the least adnantageous. 3. Means and ratio of the under 1.0mm area(C) were $198.96mm^2$, 42.65% in Group1, 123.06$mm^2$, 46.58% in Group2, and $92.24mm^2$, 29.52% in Group3. These data means that Group1 is the most advantageous in terms of masticatory effective area and Group3 is the least. 4. Means and ratio of the under 0.5mm area(B) were $86.68mm^2$, 26.68% in Group1, $62.98mm^2$, 18.71% in Group2, and $36.44mm^2$, 11.66% in Group3. These can also be considered Group1 is the most advantageous for masticatory effective area and occlusal stability. 5. Means and ratio of the under 0.05mm area(A) were $30.92mm^2$, 9.21% in Group1, $14.31mm^2$, 4.25% in Group2, and $7.59mm^2$, 2.43% in Group3. The area ratio of the each subject group was(4.1) : (1.9) : (1)and the data of the under 0.05mm area has the intimate relationship with inter-group and intra-group data/ratio. 6. First molar showed the most occlusal contact points in all subject group and Group1 showed somewhat uniformly distributed occlusal contact point except first premolar. In Group2, all contact point in posterior teeth showed significantly reduced distribution except first molar. Group3 showed evenly distributed contace points in first and second molars.

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A model for enhancing the academic excellence of adult college students (성인대학생의 학업수월성 강화를 위한 모형)

  • Kim, Eun Young;Kim, Jin Sook
    • The Journal of the Convergence on Culture Technology
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    • v.5 no.2
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    • pp.195-200
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    • 2019
  • The purpose of this study is to present a model for enhancing the academic excellence of adult college students. For this purpose, 408 adult college students attending 2-year and 4-year colleges in Busan, Daegu, and Gyeongbuk were surveyed and analyzed. The components of the model are curriculum, educational methods, evaluation of education, educational administration, educational environment, and institutional support and the results are as follows. First, the curriculum preferred by adult college students was to acquire diverse academic knowledge for a degree, to acquire knowledge and skills to develop skills for the workplace, and to acquire new information and knowledge regarding issues in society as a whole. Second, the professors' qualification among the educational methods preferred by adult college students was professional competence of the professors based on their theoretical and practical skills. The preferred teaching methods were lecture, discussion, action learning, and the project learning method in that order and video and PowerPoint were preferred as effective teaching mediums. Third, the preferred course for adult college students is operated on weekends, and three years was preferred to get a bachelor's degree. The possible hours of learning per day is 3~6 hours, indicating the necessity of e-learning, B-learning, and prior learning experience recognition systems. Fourth, the education evaluation method preferred by adult college students was a compromise method which is a mixture of absolute evaluation and relative evaluation, and it also showed the need for Pass or Non Pass evaluation method. Fifth, the internal factors of college selection preferred by adult college students were the acquisition of new knowledge and skills, and the external factors were desire to receive many opportunities related to employment and job improvement. The classroom, which provides an effective environment, was a fixed seat classroom and an indoor classroom environment was emphasized for desired educational environment. Sixth, institutional support preferred by adult college students was computer-related programs and learning club support services.

Types of tweezers and their culture of use (족집게(鑷)의 유형과 사용 문화)

  • KIM, Jihyeon
    • Korean Journal of Heritage: History & Science
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    • v.54 no.3
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    • pp.4-23
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    • 2021
  • The purpose of this study was to classify the types of tweezers used across time and to examine the social culture of periods through the use of tweezers. Chapter II summarized the terms for tweezers and looked at the use of tweezers in two cases related to the social culture and politics of a period. The first is the use of tweezers for beauty purposes. Men used tweezers as a kind of self-management to maintain their social status and power, and thus they helped develop a wide range of tweezers cultures. People with gray hair are usually old. The perception that we should step down from politics when we are aged has become strong. Therefore, politicians pulled out gray hairs with tweezers to maintain only black hair and show youth, which indicates that their social influence is still strong. The second is the use of tweezers for first aid. Chapter III classified tweezers by type during the Goryeo and Joseon periods. The tweezers are largely divided into basic and composite types. The basic type of tweezers is a form that has been continued since the Three Kingdoms Period and consists of tongs and handles, and a fixed type of tweezers with a fixed ring appeared. Composite tweezers are made by grafting earpick or multipurpose knives. Composite tweezers are all-in-one tweezers with an earpick and an all-in-one knife. Tweezers are usually all-in-one. Among the composite tweezers, rivet separation and ring separation are characterized by separation, unlike the all-in-one tweezers. The method of connecting is divided into rivets and connection rings. The all-in-one tweezers appear only during the Goryeo Dynasty and are characterized by the lifestyle that provides a glimpse of the tastes of contemporary users. The manufacturing takes shape after making a thin metal plate. Decorative techniques are carved on soft metal tweezers, such as silver and bronze with a line, point, and a pressed angle. These tweezers are presumed to have been used by the royal family or aristocrats. However, most tweezers are made of strong bronze or iron. Therefore, the majority of simple X-shaped patterns are sampled or without patterns. The biggest reason why there are such diverse types of tweezers is that the culture of tweezers was widespread regardless of the times. In addition, the basic type of tweezers has been used since the Three Kingdoms Period and has been modified and used together as necessary because the shape of tweezers is a practical daily tool. Study of metal crafts have been limited to royal objects and Buddhist crafts. We hope that research on everyday tools such as tweezers will continue to serve as an opportunity to examine the social and cultural aspects of the times in various ways.

A Study on the Current Status of Prescribed Drugs in Oriental Health Insurance and their Improvement (한방건강보험 약제 투약 실태 및 활성화 방안 연구)

  • Kwon, Yong-Chan;Yoo, Wang-Keun;Seo, Bu-Il
    • The Korea Journal of Herbology
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    • v.27 no.2
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    • pp.1-16
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    • 2012
  • Objective : To investigate the current status of prescription drugs in Oriental medical institutes and to draw up a future plan for the revitalization of Oriental medical health insurance, this survey has been performed. Method : The survey has been made with 321 doctors working at Oriental medical institutes in Daegu and Kyungbuk areas for a period of 3 month from June 1, 2010 until September 1, 2010. Result : 1. When it comes to the current status of the use of herbal drugs in Oriental Health insurance, most of doctors surveyed prescribe insurance drugs, and they prescribe insurance drugs to patients, who are less than 20% of total patients visiting their clinics. 2. The awareness of Herbal Health Care Drugs is investigated. When it comes to the understanding of the difference between insurance drugs(powder type drugs) and granular type drugs, doctors admit that they differ only in one aspect, whether or not their being covered by health insurance. Based on the survey results on the understanding of insurance coverage of granular type drugs, doctors, even though they long for granular type drugs to be accepted as insurance drugs, are worrying whether the number of outpatients might dwindle due to increased insurance co-payments. They also point out that the biggest obstacles in the expansion of the granular type drugs as insurance drugs are the lack of understanding of the government and the objection of the Health Insurance Review and Assesment service (HIRA) for fear of increased insurance claims. 3. Upon investigation on Oriental medicine doctors' understandings of herbal pharmaceutical industry, it is found that doctors' responses on pharmaceutical industry are not all positive ones('new product development and neglect of R&D infrastructure' and 'smallness of industry'). When it is investigated what area needs the greatest improvement in herbal pharmaceutical industry, 'securing sufficient capital, good manufacturing, and strengthening quality control', is the highest. 4. When it is asked what are the most needed in order to improve herbal health insurance medicine, responses such as 'the increase in the accessibility to and the utilization of Oriental medical clinics through the diversification of the means of prescriptions', 'the improvement of insurance benefits(cap adjustments)', 'increase the proportion of high quality medicinal plants', 'the ceiling of co-payments(deductible) at 20,000 won or more', 'expansion of the choices of formulations', 'formulational expansions of tablets and pills', and finally 'admittance and expansion of granular type drug as insurance drug' are the highest. 5. Upon investigating the general characteristics of the current status of the usage of Oriental health care herbal drugs, the followings are observed. First, the frequency of use of health insurance drugs by the doctors who use health insurance with general characteristics shows similar differences in case of total monthly sales amount (p<0.001), average number of daily patients (p<0.05). Secondly, as to the willingness of the expanded usage of insurance drugs, similar differences are observed in case of total monthly sales amount (p<0.05). 6. Upon investigating the general characteristics of the perception of Herbal health care drugs, the followings are observed. First, inspecting general characteristics and insurance claims due to increased co-payments(deductible amount) reveals similar differences in case of working period (p<0.01) and in case of total monthly sales amount (p <0.01). Secondly, inspecting general characteristics and the obstacles that hinder granular type drugs from being accepted as health care insurance drugs shows similar differences in case of working period (p<0.05). 7. Upon investigating the general characteristics of the understanding of Oriental Herbal pharmaceutical companies, the followings are observed. First, opinions on the general characteristics of pharmaceutical companies, when examined with variance analysis, shows similar differences in case of total monthly sales amount (p<0.05). Secondly, when opinions are examined on general characteristics and the problems of herbal pharmaceutical companies, similar differences are found in case of working period (p<0.01) and in case of total monthly sales amount (p<0.001). Lastly, opinions on the general characteristics and reforms of pharmaceutical companies, similar differences are observed in case of working period (p<0.001). 8. Upon investigating the general characteristics of the improvement of insurance Herbal drugs, the followings are observed. First, regarding general characteristics and insurance benefits, similar differences are observed in case of working period (p<0.05), in case of total monthly sales amount (p<0.05), and in case of average number of daily patients (p<0.01). Secondly, opinions on the general characteristics and the needs for the improvement of Herbal insurance drugs are examined in 5 different aspects, which are the approval of granular type drugs as insurance drugs, the expanded practices of the number of prescription insurance drugs, the needs of a variety of formulations, the needs of TFT of which numbers of Oriental medical doctors are members for the revision of the existing system, and the needs of adjusting the current ceiling of the fixed amount and the fixed rate. When processed by the analysis of variance, the results show similar differences in case of average number of daily patients (p<0.01). Conclusion : From the results of this study the first measures to take are, to reform overall insurance benefit system, including insurance co-payment system(fixed rate cap adjustment), to expand the number of the herbal drugs to be prescribed matching with insurance benefit accordingly, and to revitalize herbal medicine insurance system through the change of various formulations. In addition, it is recommended to improve the effectiveness of herbal medicine by making plans to enhance the efficacy of herbal medicine and by enabling small pharmaceutical companies to outgrow themselves.

The Method of Participatory Government to Introduce the System of Autonomous Police (참여정부의 자치경찰제 도입방안)

  • Jung, Jin-Hwan
    • Korean Security Journal
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    • no.10
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    • pp.355-385
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    • 2005
  • As the system of autonomous police that has been debated for long time is fixed to be introduced by the program of participatory government, this treatise intends to analyze main contents and review controversial items in order to present supplementary measures. The program of participatory government to introduce autonomous police in Korea focuses on converting the autonomous police of Korea from centralized police administration in order to provide 'customized security service' that is appropriate to the regional environment. Thus, if relevant city, county or district considers that it is required to introduce the system autonomous police, the assembly may enforce the decision by enacting ordinance. For enforcement, organization in the unit of section will be established in the line of mayor, county headman and district office. The main role will be security service that is closely related to the life of inhabitants such as crime prevention, patrol, traffic crackdown, etc. as well as public health, sanitation and environmental control which are being performed by autonomous organization at present. However some expected controversial items may be summarized in the following 3 points on the premise of accepting the program of government. First, the point at issue related to the basic function of police. The basic function of police is generally understood as order keeping function such as anterior and preventive job and law enforcing function such as posterior and suppressing job. By the way, the program of government does not endow the autonomous police with investigation right for general crime, thereby raising the controversy that our autonomous police is nothing but the assistant of police. Furthermore, the present national police also expresses its dissatisfaction to the transfer of authority. Second, the issue of balance of security service between self-governing bodies may be raised. The security environment is different between self-governing bodies and thus demand of security is different. Therefore, the security service of autonomous police will reveal difference in qualitative aspect for each self-governing body. Moreover, it can be easily anticipated that the quality of security service may be different as per the financial independence degree. Third, the point at issue anticipated with the operation funded by the budget of self-governing body. As autonomous police is operated by the budget of self-governing body, the following problems may be raised; (1) since police administration is subordinated to general administration, the concentration may be weakened (2) the cooperation between policy agencies may be impeded (3) owing to the difficult in possessing spare police, the mobility of police may be somewhat reduced.

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